Comparison of two fluid-management strategies in acute lung injury. Dexamethasone for the prevention of postextubation airway obstruction: a prospective, randomized, double-blind, placebo-controlled trial. Extubation outcome after spontaneous breathing trials with T-tube or pressure support ventilation. The Spanish Lung Failure Collaborative Group. Inspiratory pressure/maximal inspiratory pressure: does it predict successful extubation in critically ill infants and children? An evaluation of extubation failure predictors in mechanically ventilated infants and children Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. Effect of exogenous surfactant (calfactant) in pediatric acute lung injury: a randomized controlled trial. Placebo-controlled trial of prednisolone in children intubated for croup State Behavioral Scale: A sedation assessment instrument for infants and young children supported on mechanical ventilation* Pediatric patients with multi-organ dysfunction syndrome receiving continuous renal replacement therapy. Effect of Patient-triggered Ventilation on Respiratory Workload in Infants after Cardiac Surgery Synchronized intermittent mandatory ventilation with and without pressure support ventilation in weaning patients with COPD from mechanical ventilation. Weaning children from mechanical ventilation: a prospective randomized trial of protocol-directed versus physician-directed weaning. Noninvasive ventilation as a systematic extubation and weaning technique in acute-on-chronic respiratory failure: a prospective, randomized controlled study. Effect of prone positioning on clinical outcomes in children with acute lung injury: a randomized controlled trial. Pressure-rate products and phase angles in children on minimal support ventilation and after extubation Predictors of successful extubation in children. Deadspace to tidal volume ratio predicts successful extubation in infants and children Extubation failure in pediatric intensive care: A multiple-center study of risk factors and outcomes The cuff leak test to predict failure of tracheal extubation for laryngeal edema Protocol weaning of mechanical ventilation in medical and surgical patients by respiratory care practitioners and nurses: effect on weaning time and incidence of ventilator-associated pneumonia. Weaning from mechanical ventilation in pediatric intensive care patients Work of Breathing During Spontaneous Ventilation in Anesthetized Children: A Comparative Study Among the Face Mask, Laryngeal Mask Airway and Endotracheal Tube A comparison of four methods of weaning patients from mechanical ventilation. Spanish Lung Failure Collaborative Group. A computer-controlled ventilator weaning system. A clinical trial. 12-h pretreatment with methylprednisolone versus placebo for prevention of postextubation laryngeal oedema: a randomised double-blind trial A comparison of two methods to perform a breathing trial before extubation in pediatric intensive care patients Higher versus lower positive end-expiratory pressures in patients with the acute respiratory distress syndrome. Effect of spontaneous breathing trial duration on outcome of attempts to discontinue mechanical ventilation. Spanish Lung Failure Collaborative Group. Evaluation of predictors of weaning from mechanical ventilation in pediatric patients. Predictors of extubation success and failure in mechanically ventilated infants and children. Extubation failure in pediatric intensive care incidence and outcomes Dexamethasone in the prevention of postextubation stridor in children. Statistical evaluation of ventilator-free days as an efficacy measure in clinical trials of treatments for acute respiratory distress syndrome Risk factors for extubation failure in mechanically ventilated pediatric patients Comparison of three methods of gradual withdrawal from ventilatory support during weaning from mechanical ventilation. Spontaneous breathing trial predicts successful extubation in infants and children A prospective study of indexes predicting the outcome of trials of weaning from mechanical ventilation. Factors associated with early extubation after cardiac surgery in young children Fluid overload before continuous hemofiltration and survival in critically ill children: A retrospective analysis* Weaning children from mechanical ventilation with a computer-driven system (closed-loop protocol): A pilot study* Weaning prediction: esophageal pressure monitoring complements readiness testing. Computerized decision support for mechanical ventilation of trauma induced ARDS: results of a randomized clinical trial. Early application of positive end-expiratory pressure in patients at risk for the adult respiratory-distress syndrome. The use of cuffed versus uncuffed endotracheal tubes in pediatric intensive care. Factors affecting accidental extubations in neonatal and pediatric intensive care patients Validation of predictors of extubation success and failure in mechanically ventilated infants and children Failed extubation after cardiac surgery in young children: Prevalence, pathogenesis, and risk factors* Comparison of predictors of extubation from mechanical ventilation in children Effect of failed extubation on the outcome of mechanical ventilation.
BACKGROUND Optimal fluid management in patients with acute lung injury is unknown . Diuresis or fluid restriction may improve lung function but could jeopardize extrapulmonary-organ perfusion . METHODS In a r and omized study , we compared a conservative and a liberal strategy of fluid management using explicit protocol s applied for seven days in 1000 patients with acute lung injury . The primary end point was death at 60 days . Secondary end points included the number of ventilator-free days and organ-failure-free days and measures of lung physiology . RESULTS The rate of death at 60 days was 25.5 percent in the conservative- strategy group and 28.4 percent in the liberal- strategy group ( P=0.30 ; 95 percent confidence interval for the difference , -2.6 to 8.4 percent ) . The mean ( + /-SE ) cumulative fluid balance during the first seven days was -136+/-491 ml in the conservative- strategy group and 6992+/-502 ml in the liberal- strategy group ( P<0.001 ) . As compared with the liberal strategy , the conservative strategy improved the oxygenation index ( [ mean airway pressure x the ratio of the fraction of inspired oxygen to the partial pressure of arterial oxygen]x100 ) and the lung injury score and increased the number of ventilator-free days ( 14.6+/-0.5 vs. 12.1+/-0.5 , P<0.001 ) and days not spent in the intensive care unit ( 13.4+/-0.4 vs. 11.2+/-0.4 , P<0.001 ) during the first 28 days but did not increase the incidence or prevalence of shock during the study or the use of dialysis during the first 60 days ( 10 percent vs. 14 percent , P=0.06 ) . CONCLUSIONS Although there was no significant difference in the primary outcome of 60-day mortality , the conservative strategy of fluid management improved lung function and shortened the duration of mechanical ventilation and intensive care without increasing nonpulmonary-organ failures . These results support the use of a conservative strategy of fluid management in patients with acute lung injury . ( Clinical Trials.gov number , NCT00281268 [ Clinical Trials.gov ] . ) OBJECTIVE To determine whether dexamethasone prevents postextubation airway obstruction in young children . DESIGN Prospect i ve , r and omized , double-blind , placebo-controlled study . SETTING Pediatric intensive care unit of a university teaching hospital . PATIENTS Sixty-six children , < 5 yrs of age , intubated and mechanically ventilated for > 48 hrs . INTERVENTIONS Patients were r and omized to receive intravenous dexamethasone ( 0.5 mg/kg , maximum dose 10 mg ) or saline , every 6 hrs for six doses , beginning 6 to 12 hrs before elective extubation . MEASUREMENTS AND MAIN RESULTS Dependent variables included the presence of stridor , Croup Score , and pulsus paradoxus at 10 mins , 6 , 12 , and 24 hrs after extubation ; need for aerosolized racemic epinephrine and reintubation . The dexamethasone and placebo groups were similar in age ( median 3 months [ range 1 to 57 ] vs. 4 months [ range 1 to 59 ] , p = .6 ) , frequency of underlying airway anomalies ( 3/33 vs. 3/33 , p = 1.0 ) , and duration of mechanical ventilation ( median 3.3 days [ range 2.1 to 39 ] vs. 3.5 days [ range 2.1 to 15 ] , p = .7 ) . The dexamethasone group had a lower frequency of stridor , Croup Score , and pulsus paradoxus measurement at 10 mins and at 6 and 12 hrs after extubation . Fewer dexamethasone-treated patients required epinephrine aerosol ( 4/31 vs. 22/32 , p < .0001 ) and reintubation ( 0/31 vs. 7/32 , p < .01 ) . Three patients exited the study early-one patient in the dexamethasone group had occult gastrointestinal hemorrhage and one patient in each group had hypertension . CONCLUSION Pretreatment with dexamethasone decreases the frequency of postextubation airway obstruction in children A 2-h T-tube trial of spontaneous breathing was used in selecting patients ready for extubation and discontinuation of mechanical ventilation . However , some doubt remains as to whether it is the most appropriate method of performing a spontaneous breathing trial . We carried out a prospect i ve , r and omized , multicenter study involving patients who had received mechanical ventilation for more than 48 h and who were considered by their physicians to be ready for weaning according to clinical criteria and st and ard weaning parameters . Patients were r and omly assigned to undergo a 2-h trial of spontaneous breathing in one of two ways : with a T-tube system or with pressure support ventilation of 7 cm H2O . If a patient had signs of poor tolerance at any time during the trial , mechanical ventilation was reinstituted . Patients without these features at the end of the trial were extubated . Of the 246 patients assigned to the T-tube group , 192 successfully completed the trial and were extubated ; 36 of them required reintubation . Of the 238 patients in the group receiving pressure support ventilation  , 205 were extubated and 38 of them required reintubation . The percentage of patients who remained extubated after 48 h was not different between the two groups ( 63 % T-tube , 70 % pressure support ventilation , p = 0.14 ) . The percentage of patients falling the trial was significantly higher when the T-tube was used ( 22 versus 14 % , p = 0.03 ) . Clinical evolution during the trial was not different in patients reintubated and successfully extubated . ICU mortality among reintubated patients was significantly higher than in successfully extubated patients ( 27 versus 2.6 % , p < 0.001 ) . Spontaneous breathing trials with pressure support or T-tube are suitable methods for successful discontinuation of ventilator support in patients without problems to resume spontaneous breathing Objective To evaluate the accuracy of the initial negative inspiratory pressure ( PI ) to maximal negative inspiratory pressure ( PImax ) ratio in predicting extubation outcome for intubated infants and children . Design A prospect i ve study . Setting : Pediatric intensive care unit . Patients A sample of 50 stable intubated pediatric patients who were judged clinical ly ready for extubation . Methods Using a one-way valve , PI and PImax were measured in all patients , after which the ≦ ratioPI/PImax was calculated and its accuracy in predicting extubation outcome evaluated . Measurements and results A total of 39 patients ( 78 % ) were successfully extubated and 11 patients ( 22 % ) were not . The meanPI/PImax ratio was not significantly different between extubation successes ( 0.36±0.14 ) and failures ( 0.45±0.1 ) ( P>0.05 ) . The cut-off value of 0.3 forPI/PImax identified in adult patients did not discriminate between extubation success and failure in children . Furthermore , a discriminatory cut-off value other than 0.3 could not be identified for infants and children . Conclusion ThePI/PImax ratio can not be used to predict extubation outcome in pediatric patients . Indices that predict extubation outcome in adults should not be extrapolated to infants and children before testing and validation Abstract Objective . To assess the accuracy of traditional weaning indices in predicting extubation failure , and to compare their accuracy when indices are measured at the onset of a breathing trial ( SBT ) and at the end of the SBT before extubation . Design . Prospect i ve study . Setting . Medical-surgical intensive care unit at a tertiary care hospital . Patients . Four hundred eighteen consecutive infants and children who received mechanical ventilation for at least 48 h and were deemed ready to undergo a SBT by their primary physician . Interventions .  Respiratory frequency ( RR ) , tidal volume ( VT ) , maximal inspiratory pressure ( Pimax ) and frequency-to-tidal volume ratio ( f/VT ) were obtained within the first 5 min of breathing through a T-piece . The primary physicians were unaware of those measurements and the decision to extubate a patient was made by them . RR , VT , f/VT were remeasured before extubation by the respiratory therapists . Extubation failure was defined as needing re intubation within 48 h after extubation . The area under the receiver operating characteristic ( ROC ) curve was calculated for each index as a measure of the accuracy in predicting extubation outcome . Measurements and main results . Three hundred twenty-three patients successfully underwent the SBT and were extubated , but 48 of them ( 14 % ) required re-intubation . The ROC curve for VT , RR , Pimax and f/VT measured within the first 5 min of breathing were 0.54 , 0.56 , 0.57 and 0.57 , respectively . The ROC curve did not increase significantly when the above indices were remeasured before extubation . Conclusions . In a population which had passed SBT , the ability of the traditional weaning indices to discriminate between children successfully extubated and children re-intubated is very poor BACKGROUND Traditional approaches to mechanical ventilation use tidal volumes of 10 to 15 ml per kilogram of body weight and may cause stretch-induced lung injury in patients with acute lung injury and the acute respiratory distress syndrome . We therefore conducted a trial to determine whether ventilation with lower tidal volumes would improve the clinical outcomes in these patients . METHODS Patients with acute lung injury and the acute respiratory distress syndrome were enrolled in a multicenter , r and omized trial . The trial compared traditional ventilation treatment , which involved an initial tidal volume of 12 ml per kilogram of predicted body weight and an airway pressure measured after a 0.5-second pause at the end of inspiration ( plateau pressure ) of 50 cm of water or less , with ventilation with a lower tidal volume , which involved an initial tidal volume of 6 ml per kilogram of predicted body weight and a plateau pressure of 30 cm of water or less . The primary outcomes were death before a patient was discharged home and was breathing without assistance and the number of days without ventilator use from day 1 to day 28 . RESULTS The trial was stopped after the enrollment of 861 patients because  mortality was lower in the group treated with lower tidal volumes than in the group treated with traditional tidal volumes ( 31.0 percent vs. 39.8 percent , P=0.007 ) , and the number of days without ventilator use during the first 28 days after r and omization was greater in this group ( mean [ + /-SD ] , 12+/-11 vs. 10+/-11 ; P=0.007 ) . The mean tidal volumes on days 1 to 3 were 6.2+/-0.8 and 11.8+/-0.8 ml per kilogram of predicted body weight ( P<0.001 ) , respectively , and the mean plateau pressures were 25+/-6 and 33+/-8 cm of water ( P<0.001 ) , respectively . CONCLUSIONS In patients with acute lung injury and the acute respiratory distress syndrome , mechanical ventilation with a lower tidal volume than is traditionally used results in decreased mortality and increases the number of days without ventilator use CONTEXT Despite evidence that patients with acute lung injury ( ALI ) have pulmonary surfactant dysfunction , trials of several surfactant preparations to treat adults with ALI have not been successful . Preliminary studies in children with ALI have shown that instillation of a natural lung surfactant ( calfactant ) containing high levels of surfactant-specific protein B may be beneficial . OBJECTIVE To determine if endotracheal instillation of calfactant in infants , children , and adolescents with ALI would shorten the course of respiratory failure . DESIGN , SETTING , AND PATIENTS A multicenter , r and omized , blinded trial of calfactant compared with placebo in 153 infants , children , and adolescents with respiratory failure from ALI conducted from July 2000 to July 2003 . Twenty-one tertiary care pediatric intensive care units participated . Entry criteria included age 1 week to 21 years , enrollment within 48 hours of endotracheal intubation , radiological evidence of bilateral lung disease , and an oxygenation index higher than 7 . Premature infants and children with preexisting lung , cardiac , or central nervous system disease were excluded . INTERVENTION Treatment with intratracheal instillation of 2 doses of 80 mL/m2 calfactant or an equal volume of air placebo administered 12 hours apart . MAIN OUTCOME MEASURES Ventilator-free days and mortality ; secondary outcome measures were hospital course , adverse events , and failure of conventional mechanical ventilation . RESULTS The calfactant group experienced an acute mean ( SD ) decrease in oxygenation index from 20 ( 12.9 ) to 13.9 ( 9.6 ) after 12 hours compared with the placebo group 's decrease from 20.5 ( 14.7 ) to 15.1 ( 9.0 ) ( P = .01 ) . Mortality was significantly greater in the placebo group compared with the calfactant group ( 27/75 vs 15/77 ; odds ratio , 2.32 ; 95 % confidence interval , 1.15 - 4.85 ) , although ventilator-free days were not different . More patients in the placebo group did not respond to conventional mechanical ventilation . There were no differences in long-term complications . CONCLUSIONS Calfactant acutely improved oxygenation and significantly decreased mortality in infants , children , and adolescents with ALI although no significant decrease in the course of respiratory failure measured by duration of ventilator therapy , intensive care unit , or hospital stay was observed Many studies have attempted to find out whether steroid treatment is beneficial in children with croup , but the results have been inconclusive . We have done a prospect i ve placebo-controlled study of the effect of prednisolone on two clinical endpoints -- the duration of intubation and the need for reintubation .  Reasons for exclusion were age under 6 months , congenital airway anomalies , and previous intubation . 70 eligible children were r and omly assigned treatment with prednisolone 1 mg/kg ( n = 38 ) or placebo ( n = 32 ) every 12 h given by nasogastric tube until 24 h after extubation . 11 ( 34 % ) placebo-treated and only 2 ( 5 % ) prednisolone-treated patients required reintubation after accidental or elective extubation ( p = 0.004 , Fisher 's exact test ; odds ratio 8.9 , 95 % confidence interval 1.7 - 59.3 ) . Survival analysis with log-normal regression showed that the duration of intubation was shorter with steroid therapy ( p less than 0.003 ) and increasing age ( p less than 0.02 ) , but was not influenced by endotracheal tube size or abnormality on chest radiograph . The median duration of intubation was 138 ( 95 % CI 118 - 160 ) h in children who received placebo and 98 ( 85 - 113 ) h in the prednisolone group . Steroid therapy reduces the duration of intubation and the need for reintubation in children intubated for croup Objective : To develop and test the reliability and validity of the State Behavioral Scale for use in describing sedation/agitation levels in young intubated patients supported on mechanical ventilation . Design : In this prospect i ve , psychometric evaluation , pairs of trained pediatric critical care nurse evaluators simultaneously and independently assessed a convenience sample of pediatric intensive care unit patients along eight state/behavioral dimensions and a numeric rating scale ( NRS ) of 0 ( extremely se date d ) to 10 ( extremely agitated ) . The eight dimensions were derived from the sedation/agitation literature and expert opinion and included respiratory drive , response to ventilation , coughing , best response to stimulation , attentiveness to careprovider , tolerance to care , consolability , and movement after consoled , each with 3–5 levels . Setting : An 18-bed pediatric medical – surgical intensive care unit and 26-bed pediatric cardiovascular intensive care unit in a university-affiliated academic children ’s hospital . Patients : A total of 91 intubated mechanically ventilated patients 6 wks to 6 yrs of age provided a median of two observations ( interquartile range , 1–3 ) for a total of 198 sets of observations . Excluded were postoperative patients or those receiving neuromuscular blockade . Interventions : Patients were observed for 1 min , and then incremental levels of stimulation were applied until patient response . After 2 mins of consoling , the state behavioral assessment and NRS were completed . Measurements : Weighted kappa and intraclass coefficients were generated to assess interrater reliability of the eight dimension and NRS ratings . Distinct state behavior profiles were empirically identified from the dimension ratings using hierarchical cluster analysis using a squared Euclidean distance measure and between-groups linkage . Construct validity of these profiles was assessed by comparing group mean NRS scores using one-way analysis of variance . Main Results : Weighted kappa scores for all 198 dimension ratings ranged from .44 to .76 , indicating moderate to good interrater reliability . The intraclass coefficient of .79 was high for NRS ratings . Cluster analysis revealed five distinct state profiles , with mean NRS ratings of 1.1 , 2.5 , 4.0 , 5.3 , and 7.6 , all of which differed significantly from each other ( F = 75.8 , p < .001 ) , supporting the profiles ’ construct validity . Conclusions : Based on empirically derived state behavior profiles , we have constructed the State Behavioral Scale to allow systematic description of the sedation – agitation continuum in young pediatric patients supported on mechanical ventilation . Further studies including prospect i ve validation and describing the effect of State Behavioral Scale implementation on clinical outcomes , including the quality of sedation and length of mechanical ventilation , are warranted BACKGROUND Critical illness leading to multi-organ dysfunction syndrome ( MODS ) and associated acute renal failure ( ARF ) is less common in children compared to adult patients . As a result , many issues plague the pediatric ARF outcome literature , including a relative lack of prospect i ve study , a lack of modality stratification in subject population s and inconsistent controls for patient illness severity in outcome analysis . METHODS We now report data from the first multicenter study to assess the outcome of pediatric patients with MODS receiving continuous renal replacement therapy ( CRRT ) . One hundred twenty of 157 Registry patients ( 63 male/57 female ) experienced MODS during their course . RESULTS One hundred sixteen patients had complete data available for analysis . The most common causes leading to CRRT were sepsis ( N= 47 ; 39.2 % ) and cardiogenic shock ( N= 24 ; 20 % ) . Overall survival was 51.7 % . Pediatric Risk of Mortality ( PRISM 2 ) score , central venous pressure ( CVP ) , and % fluid overload ( % FO ) at CRRT initiation were significantly lower for survivors versus nonsurvivors . Multivariate analysis controlling for severity of illness using PRISM 2 at CRRT initiation revealed that%FO was still significantly lower for survivors versus nonsurvivors ( P < 0.05 ) even for patients receiving both mechanical ventilation and vasoactive pressors . We speculate that increased fluid administration from PICU admission to CRRT initiation is an independent risk factor for mortality in pediatric patients with MODS receiving CRRT . CONCLUSION We suggest that after initial resuscitative efforts , an increased emphasis should be placed on early initiation of CRRT and inotropic agent use over fluid administration to maintain acceptable blood pressure Background Patient-triggered ventilation ( PTV ) is commonly used in adults to avoid dyssynchrony between patient and ventilator . However , few investigations have examined the effects of PTV in infants . Our objective was to determine if pressure-control PTV reduces infants ’ respiratory workloads in proportion to the level of pressure control . We also explored which level of pressure control provided respiratory workloads similar to those after the extubation of the trachea . Methods When seven post – cardiac surgery infants , aged 1 to 11 months , were to be weaned with the pressure-control PTV , we r and omly applied five levels of pressure control : 0 , 4 , 8 , 12 , and 16 cm H2O . All patients were ventilated with assist – control mode , triggering sensitivity of 1 l/min , and positive end-expiratory pressure of 3 cm H2O . After establishing steady state conditions at each level of pressure control , arterial blood gases were analyzed and esophageal pressure ( Pes ) , airway pressure , and airflow were measured . Inspiratory work of breathing ( WOB ) was calculated using a Campbell diagram . A modified pressure – time product ( PTPmod ) and the negative deflection of Pes were calculated from the Pes tracing below the baseline . The measurement was repeated after extubation . Results Pressure-control PTV supported every spontaneous breath . By decreasing the level of pressure control , respiratory rate increased , tidal volume decreased , and as a result , minute ventilation and arterial carbon dioxide partial pressure were maintained stable . The WOB , PTPmod , and negative deflection of Pes increased as pressure control level was decreased . The WOB and PTPmod at 4 cm H2O pressure control and 0 cm H2O pressure control and after extubation were significantly greater than those at the pressure control of 16 , 12 , and 8 cm H2O ( P < 0.05 ) . The WOB and PTPmod were almost equivalent after extubation and at 4 cm H2O pressure control . Conclusions Work of breathing and PTPmod were changed according to the pressure control level in post – cardiac surgery infants .  PTV may be feasible in infants as well as in adults This prospect i ve study compared two weaning modalities in COPD patients requiring mechanical ventilation ( MV ) for acute respiratory failure . Nineteen patients with COPD were studied when their precipitating illness was controlled . Although they satisfied the conventional bedside weaning criteria , they could not tolerate any reduction in the respirator rate below 10 cycles/min . At this time , patients were r and omized into two groups receiving either synchronized intermittent m and atory ventilation ( SIMV ) with pressure support ventilation ( PSV ) ( group 1 ) or SIMV alone ( group 2 ) . The volumetric support of ventilation  ( SIMV rate ) was progressively decreased in both groups according to the patient 's tolerance with a concurrent decrease in the barometric support of ventilation ( PSV levels from 15 cm H2O to 6 cm H2O ) . At each step of SIMV rate , we found no difference between group 1 and group 2 in arterial blood gases , blood pressure , heart rate , airway occlusion pressure , maximal inspiratory pressure , and oxygen cost of breathing ( OCB ) . At each step , however , group 1 patients showed significantly higher spontaneous tidal volume and lower spontaneous breathing frequency than did group 2 patients . We found a slight but not significant tendency to a shorter weaning period with than without PSV , but no difference in the weaning success . We concluded that ( 1 ) conventional weaning criteria might be inaccurate in COPD patients , ( 2 ) SIMV appeared very useful in weaning COPD patients from MV , ( 3 ) PSV marginally reduced the weaning period when added to SIMV , and ( 4 ) the OCB was not significantly improved with PSV OBJECTIVE Compare outcomes between physician-directed and protocol -directed weaning from mechanical ventilation in pediatric patients . DESIGN Prospect ive-r and omized . SETTING Pediatric and cardiac intensive care units in a 307-bed tertiary referral hospital for children . INTERVENTIONS The control group ( physician-directed ) was weaned according to individual physician order for reduction in minute ventilation , positive end-expiratory pressure , and ordered oxygen saturation parameters for reduction in fraction of inspired oxygen ( F(IO)(2 ) ) . The study group ( protocol -directed ) was weaned according to a predetermined algorithm developed for the purpose of this investigation . METHODS The study enrolled 223 patients ( 116 physician-directed , 107 protocol -directed ) . All patients were monitored for hemodynamics , ventilator parameters , arterial blood gas values when available , oxygen saturation , weaning time , pre-weaning time , extubation time , and time on F(IO)(2 ) > or = 0.40 . We also monitored the incidence of reintubation , subglottic stenosis , tracheitis , and pneumonia . The protocol -directed group had additional measurements of actual versus predicted minute volume , comparisons of respiratory rate ( actual versus predicted for age ) , and presence of spontaneous breathing effort for 10 consecutive minutes . Data analysis was done according to intent to treat . RESULTS There was no significant difference in 12-hour and 24-hour pediatric risk of mortality ( PRISM III ) scores between groups . The protocol -directed group overall had shorter total ventilation time , weaning time , pre-weaning time , time to extubation , and time on F(IO)(2 ) > 0.40 , although after stratification for respiratory diagnosis , only the difference in weaning time remained significant . There was no difference in the incidence of reintubation , new-onset tracheitis , subglottic stenosis , or pneumonia . CONCLUSIONS Protocol -directed weaning result ed in a shorter weaning time than physician-directed weaning in these pediatric patients Prolonged duration of endotracheal mechanical ventilation ( ETMV )  is associated with an increased morbidity and mortality in intensive care unit ( ICU ) patients . The aim of this study was to assess the usefulness of noninvasive ventilation ( NIV ) as a systematic extubation and weaning technique to reduce the duration of ETMV in acute-on-chronic respiratory failure ( ACRF ) . Among 53 consecutively intubated patients admitted for ACRF , we conducted a prospect i ve , r and omized controlled trial of weaning in 33 patients who failed a 2-h T-piece weaning trial ( 2 h-WT ) although they met simple criteria for weaning . Conventional invasive pressure support ventilation ( IPSV ) was used as the control weaning technique in 16 patients ( IPSV group ) , and NIV was applied immediately after extubation in 17 patients ( NIV group ) . The two weaning groups were similar for type of chronic respiratory failure ( CRF ) , pulmonary function data , age , Simplified Acute Physiology Score ( SAPS II ) , and severity of ACRF on admission . The characteristics of the two groups were also similar at r and omization . In the IPSV group , 12 of 16 patients ( 75 % ) were successfully weaned and extubated , versus 13 of 17 ( 76.5 % ) in the NIV group ( p = NS ) . NIV like IPSV significantly and similarly improved gas exchange in relation to that achieved during 2 h-WT ( p < 0.05 ) . The duration of ETMV was significantly shorter in the NIV ( 4.56 + /- 1.85 d ) than in the IPSV group ( 7.69 + /- 3.79 d ) ( p = 0 . 004 ) . NIV also reduced the mean period of daily ventilatory support , but increased the total duration of ventilatory support related to weaning ( 3.46 + /- 1.42 d , versus 11.54 + /- 5.24 d with NIV ; p = 0 . 0001 ) . Most patients in the IPSV group developed complications related to ETMV and /or the weaning process , but the difference was not significant ( nine of 16 versus six of 17 ) . The duration s of ICU and hospital stays and the 3-mo survival were similar in the two groups . In conclusion , NIV permits earlier removal of the endotracheal tube than with conventional IPSV , and reduces the duration of daily ventilatory support without increasing the risk of weaning failures .  NIV should be considered as a new and useful systematic approach to weaning in patients with ACRF who are difficult to wean CONTEXT In uncontrolled clinical studies , prone positioning appeared to be safe and to improve oxygenation in pediatric patients with acute lung injury . However , the effect of prone positioning on clinical outcomes in children is not known . OBJECTIVE To test the hypothesis that at the end of 28 days infants and children with acute lung injury treated with prone positioning would have more ventilator-free days than those treated with supine positioning . DESIGN , SETTING , AND PATIENTS Multicenter , r and omized , controlled clinical trial conducted from August 28 , 2001 , to April 23 , 2004 , of 102 pediatric patients from 7 US pediatric intensive care units aged 2 weeks to 18 years who were treated with supine vs prone positioning .  R and omization was concealed and group assignment was not blinded . INTERVENTION Patients were r and omized to either supine or prone positioning within 48 hours of meeting acute lung injury criteria , with those patients in the prone group being positioned within 4 hours of r and omization and remaining prone for 20 hours each day during the acute phase of their illness for a maximum of 7 days , after which they were positioned supine . Both groups were treated using lung protective ventilator and sedation protocol s , extubation readiness testing , and hemodynamic , nutrition , and skin care guidelines . MAIN OUTCOME MEASURE Ventilator-free days to day 28 . RESULTS The trial was stopped at the planned interim analysis on the basis of the prespecified futility stopping rule . There were no differences in the number of ventilator-free days between the 2 groups ( mean [ SD ] , 15.8 [ 8.5 ] supine vs 15.6 [ 8.6 ] prone ; mean difference , -0.2 days ; 95 % CI , -3.6 to 3.2 ; P = .91 ) . After controlling for age , Pediatric Risk of Mortality III score , direct vs indirect acute lung injury , and mode of mechanical ventilation at enrollment , the adjusted difference in ventilator-free days was 0.3 days ( 95 % CI , -3.0 to 3.5 ; P = .87 ) . There were no differences in the secondary end points , including proportion alive and ventilator-free on day 28 ( P = .45 ) , mortality from all causes ( P>.99 ) , the time to recovery of lung injury ( P = .78 ) , organ-failure-free days ( P = .88 ) , and cognitive impairment ( P = .16 ) or overall functional health ( P = .12 ) at hospital discharge or on day 28 . CONCLUSION Prone positioning does not significantly reduce ventilator-free days or improve  other  clinical outcomes in pediatric patients with acute lung injury Objective To compare the pressure-rate products and phase angles of children during minimal support ventilation and after extubation . Design and setting Prospect i ve , r and omized single-center trial in a pediatric intensive care unit in a tertiary children ’s hospital . Methods Seventeen endotracheally intubated , mechanically ventilated children were placed on T-piece , T-piece with heliox , continuous positive airway pressure , and pressure support in r and om order . Esophageal pressure swings , phase angles , respiratory mechanics , and physiological parameters were measured on these modes and after extubation . Measurements and results Pressure-rate product postextubation was significantly higher than on support modes . For each mode and after extubation they were : pressure support 198±31 , continuous positive airway pressure 237±30 , T-piece 323±47 , T-piece/heliox 308±61 , and extubation 378±43 cmH2O/min . Phase angles were significantly higher during T-piece ventilation than pressure support but not did not differ significantly from postextubation . Conclusions Assessment of effort of breathing during even minimal mechanical ventilation may underestimate postextubation effort in children . Postextubation pressure-rate product and hence “ effort of breathing ” in children is best approximated by T-piece ventilation Objective criteria to predict extubation outcome in mechanically ventilated children are not available . Our goal was to study factors associated with extubation success and to evaluate the usefulness of the rapid shallow breathing index ( RSBI ) and the compliance , resistance , oxygenation , and pressure index ( CROP index ) in  children . Data were prospect ively collected on 227 mechanically ventilated children . Patients successfully extubated had significantly better lung compliance ( Cdyn : 0.59 + /- 0.91 versus 0.39 + /- 0.14 ml/kg/cm H(2)O ) , higher Pa(O(2))/FI(O(2 ) ) ratio ( 382.4 + /- 181.2 versus 279.8 + /- 93.9 ) , and lower Pa(CO(2 ) ) ( 41.3 + /- 6.7 versus 47.3 + /- 8.5 mm Hg ) . Spontaneous breathing parameters showed significantly lower respiratory rates ( RR ) ( 36.6 + /- 17.9 versus 52.8 + /- 23 breaths/min ) , larger tidal volumes ( VT ) ( 7.3 + /- 2.6 versus 4.9 + /- 1.8 ml/kg ) , and greater muscle strength ( negative inspiratory force [ NIF ] : 41.8 + /- 15.4 versus 35.1 + /- 12.5 cm H(2)O ) in successfully extubated children . Extubation failures had higher RSBIs and lower CROP index values . A RSBI value of < /= 8 breaths/ml/kg had a sensitivity of 74 % and specificity of 74 % , whereas a CROP value of > /= 0.15 ml/kg/breaths/min had a sensitivity of 83 % and specificity of 53 % for extubation success . Children failing extubation demonstrate abnormalities of respiratory function . The RSBI and CROP index are useful to predict pediatric extubation success Objective Using a modification of the Bohr equation , single-breath carbon dioxide capnography is a noninvasive technology for calculating physiologic dead space ( Vd/Vt ) . The objective of this study was to identify a minimal Vd/Vt value for predicting successful extubation from mechanical ventilation in pediatric patients . Design Prospect i ve , blinded , clinical study . Setting Medical and surgical pediatric intensive care unit of a university hospital . Patients Intubated children ranging in age from 1 wk to 18 yrs . Interventions None . Measurements and Main Results Forty-five patients were identified by the pediatric intensive care unit clinical team as meeting criteria for extubation . Thirty minutes before the planned extubation , each patient was begun on pressure support ventilation set to deliver an exhaled tidal volume of 6 mL/kg . After 20 mins on pressure support ventilation , an arterial blood gas was obtained , Vd/Vt was calculated , and the patient was extubated . Over the next 48 hrs , the clinical team managed the patient without knowledge of the preextubation Vd/Vt value . Of the 45 patients studied , 25 had Vd/Vt ≤0.50 . Of these patients , 24 of 25 ( 96 % ) were successfully extubated without needing additional ventilatory support . In an intermediate group of patients with Vd/Vt between 0.50 and 0.65 , six of ten patients ( 60 % ) successfully extubated from mechanical ventilation . However , only two of ten patients ( 20 % ) with a Vd/Vt ≥0.65 were successfully extubated . Logistic regression analysis revealed a significant association between lower Vd/Vt and successful extubation . Conclusions A Vd/Vt ≤0.50 reliably predicts successful extubation , whereas a Vd/Vt > 0.65 identifies patients at risk for respiratory failure following extubation . There appears to be an intermediate Vd/Vt range ( 0.51–0.65 ) that is less predictive of successful extubation . Routine Vd/Vt monitoring of pediatric patients may permit earlier extubation and reduce unexpected extubation failures Objective To determine a contemporary failed extubation rate , risk factors , and consequences of extubation failure in pediatric intensive care units ( PICUs ) . Three hypotheses were investigated : a ) Extubation failure is in part disease specific ; b ) preexisting respiratory conditions predispose to extubation failure ; and c ) admission acuity scoring does not affect extubation failure . Design Twelve-month prospect i ve , observational , clinical study . Setting Sixteen diverse PICUs in the United States . Patients Patients were 2,794 patients from the newborn period to 18 yrs of age experiencing a planned extubation trial . Interventions None . Measurements and Main Results A descriptive statistical analysis was performed , and outcome differences of the failed extubation population were determined . The extubation failure rate was 6.2 % ( 174 of 2,794 ; 95 % confidence interval , 5.3–7.1 ) . Patient features associated with extubation failure ( p < .05 ) included age ≤24 months ; dysgenetic condition ; syndromic condition ; chronic respiratory disorder ; chronic neurologic condition ; medical or surgical airway condition ; chronic noninvasive positive pressure ventilation ; the need to replace the endotracheal tube on admission to the PICU ; and the use of racemic epinephrine , steroids , helium-oxygen therapy ( heliox ) , or noninvasive positive pressure ventilation within 24 hrs of extubation . Patients failing extubation had longer pre-extubation intubation time ( failed , 148.7 hrs , sd ± 207.8 vs. success , 107.9 hrs , sd ± 171.3 ; p < .001 ) , longer PICU length of stay ( 17.5 days , sd ± 15.6 vs. 7.6 days , sd ± 11.1 ; p < .001 ) , and a higher mortality rate than patients not failing extubation ( 4.0 % vs. 0.8 % ; p < .001 ) . Failure was found to be in part disease specific , and preexisting respiratory conditions were found to predispose to failure whereas admission acuity did not . Conclusion A variety of patient features are associated with an increase in extubation failure rate , and serious outcome consequences characterize the extubation failure population in PICUs Abstract Objective . Laryngeal edema secondary to endotracheal intubation may require early re-intubation . Prior to extubation the absence of leak around an endotracheal tube may predict laryngeal edema after extubation . We evaluated the usefulness of a quantitative assessment of such a leak to identify the patients who will require early re-intubation for laryngeal edema . Methods . This prospect i ve study included 76 patients with endotracheal intubation for more than 12 h. The leak , in percent , was defined as the difference between expired tidal volume measured just before extubation , in volume-controlled mode , with the cuff inflated and then deflated . The best cut-off value to predict the need for re-intubation for significant laryngeal edema was determined and the patients were divided into two groups , according to this cut-off value . Results . Eight of the 76 patients ( 11 % ) needed re-intubation for laryngeal edema . Patients requiring re-intubation had a smaller leak than the other patients [ 9 ( 3–18 ) vs 35 (13–53)% , p<0.01 ] . The best cut-off value for gas leak was 15.5 % . The high leak group included 51 patients , of whom only two patients ( 3 % ) required re-intubation . The low leak group included 25 patients , among whom six patients ( 24 % ) required re-intubation ( p<0.01 ) . The sensitivity of this test was 75 % , the specificity 72.1 % , the positive predictive value 25 % , the negative predictive value 96.1 % and the percent of correct classification 72.4 % . Conclusions . A gas leak around the endotracheal tube greater than 15.5 % can be used as a screening test to limit the risk of re-intubation for laryngeal edema STUDY OBJECTIVES ( 1 ) To determine the effect of a single ventilator management protocol ( VMP ) used in medical and surgical ICUs on the duration of mechanical ventilation . ( 2 ) To determine the effect of a VMP on the incidence of ventilator-associated pneumonia ( VAP ) . DESIGN Prospect i ve , r and omized , controlled study . SETTING : University medical center . PATIENTS Three hundred eighty-five patients receiving mechanical ventilation between June 1997 and May 1998 . INTERVENTIONS A respiratory care practitioner- and registered nurse-driven VMP . RESULTS Intervention and control groups were comparable with respect to age , sex , severity of illness and injury , and duration of respiratory failure at the time of r and omization . The duration of mechanical ventilation for patients was decreased from a median of 124 h for the control group to 68 h in the VMP group ( p = 0.0001 ) . Thirty-one total instances of VAP were noted . Twelve patients in the surgical control group had VAP , compared with 5 in the surgical VMP group ( p = 0.061 ) . The impact of the  VMP  on VAP frequency was less for medical patients . Mortality and ventilator discontinuation failure rates were similar between control and VMP groups . CONCLUSIONS A VMP design ed for multidisciplinary use was effective in reducing duration of mechanical ventilatory support without any adverse effects on patient outcome . The VMP was also associated with a decrease in incidence of VAP in trauma patients . These results , in conjunction with prior studies , suggest that VMPs are highly effective means of improving care , even in university ICUs Objective : The development of weaning predictors in mechanically ventilated children has not been sufficiently investigated . The purpose of this study was to evaluate the accuracy of some weaning indices in predicting weaning failure . Design : Prospect i ve , interventional study . Setting : University-affiliated children 's hospital with a 19-bed intensive care unit . Patients : 84 consecutive infants and children requiring mechanical ventilation for at least 48 h and judged ready to wean by their primary physicians . Interventions : Patients who met the criteria to start weaning underwent a trial of spontaneous breathing lasting up to 2 h. Bedside measurements of respiratory function were obtained immediately before discontinuation of mechanical ventilation and within the first 5 min of spontaneous breathing . The primary physicians were blinded to those measurements , and the decision to extubate a patient at the end of the spontaneous breathing trial or reinstitute mechanical ventilation was made by them . Failure to wean was defined as the requirement for mechanical ventilation at any time during the trial of spontaneous breathing ( trial failure ) or needing reintubation within 48 h of extubation ( extubation failure ) . Measurements and main results : Seventy-five patients had neither signs of respiratory distress nor deterioration in gas exchange during the trial and were extubated . Twelve patients required reintubation within 48 h. In 9 patients , mechanical ventilation was reinstituted after a median duration of the spontaneous breathing trial of 35 min . The only independent predictor of trial failure was tidal volume indexed to body weight [ odds ratio 2.60 , 95 % confidence interval ( CI ) 1.40 to 24.9 ] . The only independent predictor of extubation failure was frequency-to-tidal volume ratio indexed to body weight ( odds ratio 1.23 , 95 % CI 1.11 to 1.36 ) . The sensitivity , specificity , and positive and negative predictive values to predict weaning failure were calculated for each of the above variables . These values were 0.48 , 0.86 , 0.53 , and 0.83 , respectively , for a frequency-to-tidal volume ratio higher than 11 breaths/min per ml per kg and 0.43 , 0.94 , 0.69 , and 0.83 , respectively , for a tidal volume lower than 4 ml/kg . Conclusions : Three-quarters of ventilated children can be successfully weaned after a trial of spontaneous breathing lasting 2 h. Both tidal volume and frequency-to-tidal volume ratio indexed to body weight were poor predictors of weaning failure in the study population Work of breathing ( WOB ) increases during general anesthesia in adults , but such information has been limited in pediatric patients . We studied WOB in 24 healthy children ( mean age 2 ± 1.9 yrs ) , during elective urogenital surgery under 1 minimum alveolar anesthetic concentration halothane-nitrous oxide anesthesia with a caudal block while breathing spontaneously . WOB was measured with an esophageal balloon , miniature flowmeter , and a computerized ( Bicore ) system . In each patient , WOB was computed under four conditions : a mask without oral airway ( -AW ) , a mask with oral airway ( + AW ) , a laryngeal mask airway ( LMA ) , and an endotracheal tube ( ETT ) . With each apparatus WOB was studied both with continuous positive airway pressure ( CPAP ) ( 5–6 cm H2O ) and without CPAP ( or zero end-expiratory pressure [ ZEEP ] ) . Under ZEEP , WOB ( g · cm/kg ) among the four apparatus were ( mean ± sem ) : mask ( -AW ) ( 64 ± 19.2 ) > mask ( + AW ) ( 44 ± 17.2 ) , LMA ( 42 ± 15.6 ) > ETT ( 25.4 ± 12.4 ) ( P < 0.05 ) . WOB with CPAP significantly ( P < 0.05 ) decreased from WOB with ZEEP in three groups ( mask [ -AW ] , mask [ + AW ] , and LMA ) , but not in the ETT group . Tidal volume ( both ZEEP and CPAP ) and end-tidal Pco2 ( with CPAP only ) were significantly ( P < 0.05 ) decreased only in the ETT group , whereas no significant difference was found in respiratory rate or minute volume among the four airway apparatus groups , either with or without CPAP . The reduction in WOB , when breathing through ETT was primarily attributable to decreases in tidal volume and volume work . The finding that WOB decreases with CPAP in all groups except for the ETT group suggests that the decrease is a result of improved patency of the upper airway rather than of increases in functional residual capacity and lung compliance . Implication s We studied work of breathing ( WOB ) measured with four airway devices , with and without application of continuous positive airway pressure ( CPAP ) . Laryngeal mask airway and mask with oral airway decrease WOB compared with mask alone . CPAP decreases WOB with all devices except the endotracheal tube . Increased WOB appears mostly because of soft tissue upper airway obstruction BACKGROUND Weaning patients from mechanical ventilation  is an important problem in intensive care units . Weaning is usually conducted in an empirical manner , and a st and ardized approach has not been developed . METHODS We carried out a prospect i ve , r and omized , multicenter study involving 546 patients who had received mechanical ventilation for a mean ( + /- SD ) of 7.5 + /- 6.1 days and who were considered by their physicians to be ready for weaning . One hundred thirty patients had respiratory distress during a two-hour trial of spontaneous breathing . These patients were r and omly assigned to undergo one of four weaning techniques : intermittent m and atory ventilation , in which the ventilator rate was initially set at a mean ( + /- SD ) of 10.0 + /- 2.2 breaths per minute and then decreased , if possible , at least twice a day , usually by 2 to 4 breaths per minute ( 29 patients ) ; pressure-support ventilation , in which pressure support was initially set at 18.0 + /- 6.1 cm of water and then reduced , if possible , by 2 to 4 cm of water at least twice a day ( 37 patients ) ; intermittent trials of spontaneous breathing , conducted two or more times a day if possible ( 33 patients ) ; or a once-daily trail of spontaneous breathing ( 31 patients ) . St and ardized protocol s were followed for each technique . RESULTS The median duration of weaning was 5 days for intermittent m and atory ventilation ( first quartile , 3 days ; third quartile , 11 days ) , 4 days for pressure-support ventilation ( 2 and 12 days , respectively ) , 3 days for intermittent ( multiple ) trials of spontaneous breathing ( 2 and 6 days , respectively ) , and 3 days for a once-daily trial of spontaneous breathing ( 1 and 6 days , respectively ) . After adjustment for other covariates , the rate of successful weaning was higher with a once-daily trial of spontaneous breathing than with intermittent m and atory ventilation ( rate ratio , 2.83 ; 95 percent confidence interval , 1.36 to 5.89 ; P < 0.006 ) or pressure-support ventilation ( rate ratio , 2.05 ; 95 percent confidence interval , 1.04 to 4.04 ; P < 0.04 ) . There was no significant difference in the rate of success between once-daily trials and multiple trials of spontaneous breathing . CONCLUSIONS A once-daily trial of spontaneous breathing led to extubation about three times more quickly than intermittent m and atory ventilation and about twice as quickly as pressure-support ventilation . Multiple daily trials of spontaneous breathing were equally successful The purpose of this study was to determine if a computer-directed weaning system could wean patients with complex medical problems from mechanical ventilation and appropriately respond to signs of respiratory failure more effectively than traditional physician-directed weaning methods . In a prospect i ve , r and omized , controlled study , we tested the system in 15 patients who had required prolonged mechanical ventilation and met predetermined weaning tests . Patients were r and omly assigned to one of two groups : ( 1 ) automatic , computer-directed weaning or ( 2 ) physician-controlled weaning . The computer-directed system decreased or increased the synchronized intermittent m and atory ventilation rate and pressure support ( PS ) based on predetermined limits of patient respiratory rate ( RR ) and tidal volume ( TV ) . Pulse oximeter oxygen saturation was monitored , and alarms were triggered by an oxygen saturation of < 90 percent . In the physician control group , weaning progressed with SIMV rate and PS reduction , as judged appropriate by the physician . Nine patients were assigned to the computer group ; six patients were assigned to the control group . The average patient age was 64.8 + /- 14.9 years for the computer group , 65.2 + /- 22.7 years for the control group . The average time on mechanical ventilation prior to weaning was 13.4 + /- 7.8 days for the computer group and 14.5 + /- 11.1 days for the control group . Seven of the nine computer group patients weaned within 48 h of the study , with an average time to wean of 18.7 + /- 5.9 h. All seven were breathing spontaneously 48 h after weaning . Two of the six control group patients weaned within 48 h of the study , with an average time of 25.6 + /- 5.6 h. Both patients who weaned were placed back on mechanical ventilation within 30 h. The number of arterial blood gas sample s drawn during the study was 1.4 + /- 0.7 for the computer group , 7.2 + /- 4.3 for the control group . The number of minutes per hour outside acceptable limits of RR > 30 , RR < 8 , or TV < 5 ml/kg was 3.2 + /- 2.8 min for the computer group and 6.6 + /- 4.1 min for the control group . The study suggests that use of the computer-directed weaning system results in fewer arterial blood gas sample s , shorter weaning times , and less time spent outside acceptable RR and TV parameters BACKGROUND The efficacy of corticosteroids in reducing the incidence of postextubation laryngeal oedema is controversial . We aim ed to test our hypothesis that methylprednisolone started 12 h before a planned extubation could prevent postextubation laryngeal oedema . METHODS We did a placebo-controlled , double-blind multicentre trial in 761 adults in intensive-care units . Patients who were ventilated for more than 36 h and underwent a planned extubation received intravenous  20 mg methylprednisolone ( n=380 ) or placebo ( 381 ) 12 h before extubation and every 4 h until tube removal . The primary endpoint was occurrence of laryngeal oedema within 24 h of extubation . Laryngeal oedema was clinical ly diagnosed and deemed serious if tracheal reintubation was needed . Analyses were done on a per protocol and intention-to-treat basis . This trial is registered at Clinical Trials.gov , number NCT00199576 . FINDINGS 63 patients could not be assessed , mainly because of self-extubation ( n=16 ) or cancelled extubation ( 44 ) between r and omisation and planned extubation . 698 patients were analysed ( 343 in placebo group , 355 in methylprednisolone group ) . Methylprednisolone significantly reduced the incidence of postextubation laryngeal oedema ( 11 of 355 , 3%vs 76 of 343 , 22 % , p<0.0001 ) , the global incidence of reintubations ( 13 of 355 , 4%vs 26 of 343 , 8 % , p=0.02 ) , and the proportion of reintubations secondary to laryngeal oedema ( one of 13 , 8 % vs 14 of 26 , 54 % , p=0.005 ) . One patient in each group died after extubation , and atelectasia occurred in one patient given methylprednisolone . INTERPRETATION Methylprednisolone started 12 h before a planned extubation substantially reduced the incidence of postextubation laryngeal oedema and reintubation . Such pretreatment should be considered in adult patients before a planned extubation that follows a tracheal intubation of more than 36 Abstract . Objective : To compare the percentage of infants and children successfully extubated  after a trial of breathing performed with either pressure support or T-piece . Design : Prospect i ve and r and omized study . Setting : Three medical-surgical pediatric intensive care units ( PICUs ) . Patients : Two hundred fifty-seven consecutive infants and children who received mechanical ventilation for at least 48 h and were deemed ready to undergo a breathing trial by their primary physician . Interventions : Patients were r and omly assigned to undergo a trial of breathing in one of two ways : pressure support of 10 cmH2O or T-piece . Bedside measurements of respiratory function were obtained immediately before discontinuation of mechanical ventilation and within the first 5 min of breathing through a T-piece . The primary physicians were unaware of those measurements , and the decision to extubate a patient at the end of the breathing trial was made by them . Measurements and main results : Of the 125 patients in the pressure support group , 99 ( 79.2 % ) completed the breathing trial and were extubated , but 15 of them ( 15.1 % ) required reintubation within 48 h. Of the 132 patients in the T-piece group , 102 ( 77.5 % ) completed the breathing trial and were extubated , but 13 of them ( 12.7 % ) required reintubation within 48 h. The percentage of patients who remained extubated for 48 h after the breathing trial did not differ in the pressure support and T-piece groups ( 67.2 % versus 67.4 % , p=0.97 ) . Conclusions : In infants and children mechanically ventilated , successful extubation was achieved equally effectively after a first breathing trial performed with pressure support of 10 cmH2O or a T-piece BACKGROUND Most patients requiring mechanical ventilation for acute lung injury and the acute respiratory distress syndrome ( ARDS ) receive positive end-expiratory pressure ( PEEP ) of 5 to 12 cm of water . Higher PEEP levels may improve oxygenation and reduce ventilator-induced lung injury but may also cause circulatory depression and lung injury from overdistention . We conducted this trial to compare the effects of higher and lower PEEP levels on clinical outcomes in these patients . METHODS We r and omly assigned 549 patients with acute lung injury and ARDS to receive mechanical ventilation with either lower or higher PEEP levels , which were set according to different tables of predetermined combinations of PEEP and fraction of inspired oxygen . RESULTS Mean ( + /-SD ) PEEP values on days 1 through 4 were 8.3+/-3.2 cm of water in the lower-PEEP group and 13.2+/-3.5 cm of water in the higher-PEEP group ( P<0.001 ) . The rates of death before hospital discharge were 24.9 percent and 27.5 percent , respectively ( P=0.48 ; 95 percent confidence interval for the difference between groups , -10.0 to 4.7 percent ) . From day 1 to day 28 , breathing was unassisted for a mean of 14.5+/-10.4 days in the lower-PEEP group and 13.8+/-10.6 days in the higher-PEEP group ( P=0.50 ) . CONCLUSIONS These results suggest that in patients with acute lung injury and ARDS who receive mechanical ventilation with a tidal-volume goal of 6 ml per kilogram of predicted body weight and an end-inspiratory plateau-pressure limit of 30 cm of water , clinical outcomes are similar whether lower or higher PEEP levels are used The duration of spontaneous breathing trials before extubation has been set at 2 h in research studies , but the optimal duration is not known . We conducted a prospect i ve , multicenter study involving 526 ventilator-supported patients considered ready for weaning , to compare clinical outcomes for trials of spontaneous breathing with target duration s of 30 and 120 min . Of the 270 and 256 patients in the 30- and 120-min trial groups , respectively , 237 ( 87.8 % ) and 216 ( 84.8 % ) , respectively , completed the trial without distress and were extubated ( p = 0.32 ) ; 32 ( 13.5 % ) and 29 ( 13.4 % ) , respectively , of these patients required reintubation within 48 h. The percentage of patients who remained extubated for 48 h after a spontaneous breathing trial did not differ in the 30- and 120-min trial groups ( 75.9 % versus 73.0 % , respectively , p = 0.43 ) . The 30- and 120-min trial groups had similar within-unit mortality rates ( 13 and 9 % , respectively ) and in-hospital mortality rates ( 19 and 18 % , respectively ) . Reintubation was required in 61 ( 13.5 % ) patients , and these patients had a higher mortality ( 20 of 61 , 32.8 % ) than did patients who tolerated extubation ( 18 of 392 , 4.6 % ) ( p < 0.001 ) . Neither measurements of respiratory frequency , heart rate , systolic blood pressure , and oxygen saturation during the trial , nor other functional measurements before the trial discriminated between patients who required reintubation from those who tolerated extubation . In conclusion , after a first trial of spontaneous breathing , successful extubation was achieved equally effectively with trials targeted to last 30 and 120 min Objective criteria for ending mechanical ventilation have not been established for infants and children . A recent study in adult patients developed two new indexes , the Rapid Shallow Breathing Index ( RSB ) and the CROP Index for predicting success or failure of extubation . We decided to evaluate the applicability of these indices to intubated , mechanically ventilated pediatric patients . For this evaluation the indices were adapted to the physiology of infants and children . A pneumotachograph was used to measure spontaneous tidal volume , respiratory rate and dynamic compliance . The tidal volume and the dynamic compliance were corrected for the patient 's body weight . Based on the data collected a cutoff value for each index was determined . Of 47 sets of patient data , 38 ( 81 % ) were collected during successful extubations , 9 ( 19 % ) during failed extubations . A modified CROP index value of > or = 0.1 ml x mmHg/bpm/kg and a modified RSB index value of < or = 11 bpm/mlkg were identified as predictive of successful extubation . The modified CROP cutoff value produced a sensitivity and specificity of 1.0 ; respective values for the modified RSB cutoff value are 0.79 and 0.78 . Cutoff values of > or = 0.1 and < or = 11 for the modified CROP index and RSB index , respectively , appear to be predictive of successful extubation in the pediatric population . Our data identifies the modified CROP index as a superior discriminator between successful and unsuccessful extubation OBJECTIVE To predict extubation success and failure in mechanically ventilated infants and children using bedside measures of respiratory function . DESIGN Prospect i ve collection of data . SETTING A university-affiliated children 's hospital with a 51-bed critical care unit . PATIENTS All infants and children who were mechanically ventilated for at least 24 hrs , except neonates < or = 37 wks gestation and patients with neuromuscular disease . INTERVENTIONS Bedside measurements of cardiorespiratory function were obtained immediately before extubation . MEASUREMENTS AND MAIN RESULTS Extubation failure was defined as reintubation within 48 hrs of extubation in the absence of upper airway obstruction . Failure rates were calculated for different ranges ( selected a priori ) of preextubation measures of breathing effort , ventilatory support , respiratory mechanics , central inspiratory drive , and integrated indices useful in adults . Effort of spontaneous breathing was assessed by the respiratory rate st and ardized to age , the presence of retractions and paradoxical breathing , inspiratory pressure , maximal negative inspiratory pressure ( maximal negative inspiratory pressure ) , inspiratory pressure/maximal negative inspiratory pressure ratio , and tidal volume indexed to body weight of a spontaneous breath . Ventilatory support was measured by the fraction of inspired oxygen ( F10(2 ) ) , mean airway pressure , oxygenation index , and the fraction of total minute ventilation provided by the ventilator . Respiratory mechanics were assessed by determination of peak ventilatory inspiratory pressure and dynamic compliance . Central inspiratory drive was assessed by mean inspiratory flow . Frequency to tidal volume ratio and the compliance , rate , oxygenation , and pressure indexed to body weight , the integrated indices useful in predicting extubation failure in adults , were also calculated . Thirty-four of the 208 patients who were studied were reintubated for an overall failure rate of 16.3 % ( 95 % confidence interval 11.3 % to 21.4 % ) . The reasons for reintubation were poor effort ( n = 8) , excessive effort ( n = 14 ) , altered mental status or absent airway reflexes ( n = 2 ) , cardiovascular instability ( n = 3 ) , inadequate oxygenation ( n = 3 ) , respiratory acidosis ( n = 3 ) , and undocumented ( n = 1 ) . Extubation failure increased significantly with decreasing tidal volume indexed to body weight of a spontaneous breath , increasing F10(2 ) , increasing mean airway pressure , increasing oxygenation index , increasing fraction of total minute ventilation provided by the ventilator , increasing peak ventilatory inspiratory pressure , or decreasing mean inspiratory flow ( p < .05 ) . Dynamic compliance showed a trend of increasing failure rate with decreasing dynamic compliance but did not reach statistical significance ( p = .116 ) . Respiratory rate st and ardized to age , inspiratory pressure , maximal negative inspiratory pressure , inspiratory pressure/maximal negative inspiratory pressure ratio , frequency to tidal volume ratio , and compliance , rate , oxygenation , and pressure did not show any trend in failure rate with increasing or decreasing values . Threshold values that defined a low risk ( < or = 10 % ) and a high risk ( > or = 25 % ) of extubation failure could be determined for tidal volume indexed to body weight of a spontaneous breath , F10(2 ) , mean airway pressure , oxygenation index , fraction of total minute ventilation provided by the ventilator , peak ventilatory inspiratory pressure , dynamic compliance , and mean inspiratory flow . Neither a low nor a high risk of failure could be defined for frequency to tidal volume ratio or the compliance , rate , oxygenation , and pressure ( CROP ) index . CONCLUSIONS Bedside measurements of respiratory function can predict extubation success and failure in infants and children . Both a low risk and a high risk of failure can be determined using these measures . Integrated indices useful in adults do not reliably predict extubation success or failure Objectives : To evaluate the hypotheses that children requiring reintubation are at an increased risk of prolonged hospitalizations , congenital heart disease , and death compared with age- and disease-severity-matched control patients . Design : Prospect i ve decision to evaluate all children undergoing extubation over a 5-yr time interval ( 1997–2001 ) with retrospective analysis of all failed extubation patients . Setting : A large multidisciplinary , dual-site , single-system pediatric intensive care unit caring for critically ill and injured children . Patients : All children intubated and ventilated during the study period ( 1997–2001 ) . Interventions : None . Measurements and Main Results : Failed extubation was defined as the unanticipated requirement to replace an endotracheal tube within 48 hrs of extubation . One hundred thirty children of 3,193 pediatric intensive care unit patients  failed extubation ( 4.1 % ) . The  median age of children who failed extubation was 6.5 months , compared with a median age of 21.3 months in the control population . The median age of failed extubation in children with cardiac disease was 9.3 months . Failed extubation patients had lengthier hospital and pediatric intensive care unit stays , longer duration of mechanical ventilation , and a higher rate of tracheostomy placement than nonfailed extubation patients ( p < .001 ) . Children with congenital heart disease who failed extubation had the longest duration of hospitalization ( 40.0 ± 5.4 days ) . Conversely , cardiac patients who did not fail extubation had the shortest length of stay ( 11.2 ± 0.4 days ) . Conclusions : In the present trial , 4.1 % of mechanically ventilated children failed extubation . Pediatric intensive care unit patients with failed extubation have longer hospital , pediatric intensive care unit , and ventilator courses but are not at increased risk of death relative to nonfailed extubation patients To assess whether there is any advantage in the use of corticosteroid to prevent  postextubation stridor in children , we conducted a prospect i ve , r and omized , double-blind trial of dexamethasone versus saline solution . The patients were evaluated and then r and omly selected to receive either dexamethasone or saline solution according to a stratification based on risk factors for postextubation stridor : age , duration of intubation , upper airway trauma , circulatory compromise , and tracheitis . Dexamethasone , 0.5 mg/kg , was given every 6 hours for a total of six doses beginning 6 to 12 hours before and continuing after endotracheal extubation in a pediatric intensive care setting . There was no statistical difference in incidence of postextubation stridor in the two groups ; 23 of 77 children in the placebo group and 16 of 76 in the dexamethasone group had stridor requiring therapy ( p = 0.21 ) . We conclude that the routine use of corticosteroids for the prevention of postextubation stridor during uncomplicated pediatric intensive care airway management is unwarranted Objective Trials of potential new therapies in acute lung injury are difficult and expensive to conduct . This article is design ed to determine the utility , behavior , and statistical properties of a new primary end point for such trials , ventilator-free days , defined as days alive and free from mechanical ventilation . Describing the nuances of this outcome measure is particularly important because using it , while ignoring mortality , could result in misleading conclusions . Design To develop a model for the duration of ventilation and mortality and fit the model by using data from a recently completed clinical trial . To determine the appropriate test statistic for the new measure and derive a formula for power . To determine a formula for the probability that the test statistic will reject the null hypothesis and mortality will simultaneously show improvement . To plot power curves for the test statistic and determine sample sizes for reasonable alternative hypotheses . Setting Intensive care units . Patients Patients with acute respiratory distress syndrome or acute lung injury as defined by the American-European Consensus Conference . Main Results The proposed model fit the clinical data . Ventilator-free days were improved by lower tidal volume ventilation , but the improvement was mostly caused by the improved mortality rate , so trials that expected similar effects would only have modest increase in power if they used ventilator-free days as their primary end point rather than 28-day mortality . Similar results were obtained using the model in two groups segregated by low or high Acute Physiology and Chronic Health Evaluation score . On the other h and , if patients are divided into two groups on the basis of the lung injury score , both the duration of ventilation and mortality are lower in the low lung injury score group . A trial of a treatment that had a similar clinical effect would have a large increase in power , allowing for a reduction in the required sample size . Conclusions Use of ventilator-free days as a trial end point allows smaller sample sizes if it is assumed that the treatment being tested simultaneously reduces the duration of ventilation and improves mortality . It is unlikely that a treatment that led to higher mortality could lead to a statistically significant improvement in ventilator-free days . This would be especially true if the treatment were also required to produce a nominal improvement in mortality Objective : To describe the incidence of extubation failure and its associated risk factors among mechanically ventilated children . Method : Prospect i ve cohort study . Children who were mechanically ventilated for longer than 12 hrs were followed up to 48 hrs after extubation . Cases of upper airway obstruction , accidental extubation , tracheostomy , or death before extubation were excluded . Extubation failure was defined as reintubation within 48 hrs after extubation . Student ’s t-test , Mann-Whitney , and chi-squared tests , odds ratio with 95 % confidence interval , and multivariate analysis were used for data analysis . Results : Extubation failure rate was 10.5 % ( 13 of 124 patients ) . Variables associated with extubation failure were age between 1 and 3 mos ( odds ratio [ OR ] = 5.68 ; 95 % confidence interval [ CI ] = 1.58–20.42 ) , mechanical ventilation > 15 days ( OR = 6.36 ; 95 % CI = 1.32–30.61 ) , mean oxygenation index ( OI ) > 5 ( OR = 4.08 ; 95 % CI = 1.25–13.30 ) , mean airway pressure 24 hrs before extubation lower than 5 cm H2O ( OR = 6.03 ; 95 % CI = 1.48–24.60 ) , continuous positive airway pressure ( CPAP ) ( OR = 4.71 ; 95 % CI = 1.34–16.58 ) , dopamine and dobutamine use ( OR = 3.71 ; 95 % CI = 1.08–12.78 ) , intravenous sedation > 10 days ( OR = 6.60 ; 95 % CI = 1.62–26.90 ) , tachypnea and subcostal retractions ( relative risk [ RR ] = 3.68 ; 95 % CI = 1.14–11.93 ) , and inspired fraction of oxygen (Fio2)>0.4 after extubation ( RR = 3.63 ; 95 % CI = 1.21–10.88 ) . After multiple logistic regression analysis , age between 1 and 3 mos , mean OI > 5 , CPAP and mechanical ventilation > 15 days remained associated with extubation failure . Conclusion : Extubation failure was more frequent among young infants who received prolonged ventilatory support and intravenous sedation , used CPAP , had impaired lung oxygenation , and required inotropic therapy Several modalities of ventilatory support have been proposed to gradually withdraw patients from mechanical ventilation , but their respective effects on the outcome of weaning from mechanical ventilation are not known . We conducted a r and omized trial in three intensive care units in mechanically ventilated patients who met st and ard weaning criteria . Those who could not sustain 2 h of spontaneous breathing were r and omly assigned to be weaned with T-piece trials , with synchronized intermittent m and atory ventilation ( SIMV ) , or with pressure support ventilation ( PSV ) . Specific criteria for performing tracheal extubation were defined for each modality . The number of patients who could not be separated from the ventilator at 21 d ( i.e. , who failed to wean ) was compared between the groups . Patients in whom tracheal intubation was required in a 48-h period following extubation were also classified as failures . Among 456 mechanically ventilated patients who met weaning criteria , 109 entered into the study ( 35 with T piece , 43 with SIMV , and 31 with PSV )  . The three groups were comparable in terms of etiology of disease or characteristics at entry in the study . When all causes for weaning failure were considered , a lower number of failures was found with PSV than with the other two modes , with the difference just reaching the level of significance ( 23 % for PSV , 43 % for T piece , 42 % for SIMV ; p = 0.05 ) . After excluding patients whose weaning was terminated for complications unrelated to the weaning process , the difference became highly significant ( 8 % for PSV versus 33 % and 39 % , p < 0.025 ) . ( ABSTRACT TRUNCATED AT 250 WORDS Objective : To assess the value of a spontaneous breathing trial ( SBT ) using a flow-inflating bag in predicting extubation success . Secondary goals were to evaluate the positive and negative predictive accuracy of a 15-min SBT . Design : Prospect i ve , blinded , clinical study . Setting : Pediatric intensive care unit ( ICU ) of a university hospital Patients : Infants and children intubated for ≥24 hrs . Interventions : Patients who met defined criteria for extubation underwent a 15-min SBT connected to a flow-inflating bag set to provide 5 cm H2O continuous positive airway pressure . Measurements and Main Results : Seventy patients underwent the SBT .  Respiratory rate , heart rate , blood pressure , and pulse oxygen saturations were recorded at baseline and at 5 and 15 mins into the SBT . The ICU physicians were blinded to the results of the SBT , and all patients were extubated at the end of the trial . Patients were observed for the next 24 hrs , and the need for noninvasive ventilation or reintubation ( i.e. , extubation failure ) was recorded . Sixty-four patients ( 91 % ) passed the SBT with a subsequent extubation failure rate of 7.8 % ( only 1.6 % required reintubation ) . Six of the 70 ( 9 % ) patients enrolled failed the trial , but half were extubated successfully . Successful completion of the SBT has a 95 % sensitivity for predicting successful extubation with a positive predictive value of 92 % and an odds ratio of 12 ( 95 % confidence interval , 1.3 , 53.7 ) . The specificity of the SBT was 37 % with a negative predictive value of 50 % . Logistic regression analysis revealed a significant association between passing the SBT and extubation success ( p = .017 ) . Conclusions : A 15-min flow-inflating bag SBT represents a practical , reliable bedside test that has 95 % sensitivity for predicting extubation success in pediatric ICU patients . A trial failure is associated with but does not accurately predict extubation failure BACKGROUND The traditional predictors of the outcome of  weaning  from  mechanical ventilation -- minute ventilation ( VE ) and maximal inspiratory pressure (Plmax)--are frequently inaccurate . We developed two new indexes : the first quantitates rapid shallow breathing as the ratio of respiratory frequency to tidal volume ( f/VT ) , and the second is termed CROP , because it integrates thoracic compliance , respiratory rate , arterial oxygenation , and Plmax . METHODS The threshold values for each index that discriminated best between a successful and an unsuccessful outcome of weaning were determined in 36 patients , and the predictive accuracy of these values was then tested prospect ively in an additional 64 patients .  Sensitivity and specificity were calculated , and the data were also analyzed with receiver-operating-characteristic ( ROC ) curves , in which the proportions of true positive results and false positive results are plotted against each other for a number of threshold values of an index ; the area under the curve reflects the accuracy of the index . RESULTS Sensitivity was highest for Plmax ( 1.00 ) , followed closely by the f/VT ratio ( 0.97 ) . Specificity was highest for the f/VT ratio ( 0.64 ) and lowest for Plmax ( 0.11 ) . The f/VT ratio was the best predictor of successful weaning , and Plmax and the f/VT ratio were the best predictors of failure . The area under the ROC curve for the f/VT ratio ( 0.89 ) was larger than that under the curves for the CROP index ( 0.78 , P less than 0.05 ) , Plmax ( 0.61 , P less than 0.001 ) , and VE ( 0.40 , P less than 0.001 ) . CONCLUSIONS Rapid shallow breathing , as reflected by the f/VT ratio , was the most accurate predictor of failure , and its absence the most accurate predictor of success , in weaning patients from mechanical ventilation Objective Children undergoing congenital heart surgery require mechanical ventilation . We sought to identify pre- and intraoperative factors ( PrO , IO ) associated with successful early extubation < 24 hrs . Design and Patients We performed a retrospective chart review of children < 36 months old who underwent congenital heart surgery from January 1998 to July 1999 . Setting Pediatric intensive care unit in a children ’s hospital . Measurements Generalized Estimating Equation models were fit to assess the association between  PrO and IO and early extubation while accounting for the correlation between surgeries performed on the same patient . Estimated odds ratios ( EOR ) and 95 % confidence intervals were calculated . Multivariable models were constructed using a forward selection process with inclusion criteria of p < .05 . Multivariable models , which included PrO and IO variables , were adjusted for procedure group . The area under the receiver operating characteristic curve was computed for each model . Results A total of 203 children underwent 219 surgeries ; 103 ( 47 % ) children were extubated in < 24 hrs , with only one ( 1 % ) failed extubation . PrO variables associated with successful early extubation included age > 6 months ( EOR , 6.1 ) , absence of pulmonary hypertension ( EOR , 9.1 ) , gestational age > 36 wks ( EOR , 4.6 ) , and absence of congestive heart failure ( EOR , 2.4 ) . IO variables were less likely to be associated with successful early extubation . Our model of PrO variables with multiple factors showed that presence of two factors was associated with an EOR of 4.2 for successful early extubation compared with children with zero or one factor . Presence of three and four factors was associated with an EOR of 18.0 and 76.5 , respectively . The area under the receiver operating characteristic curve for this model is 0.816 . Incision type , complex vs. simple procedure , and palliative vs. complete repair were not associated with success of early extubation . Conclusions Early extubation is possible in many very young children undergoing congenital heart surgery , with a low rate of failed extubation . The model would be improved by prospect i ve validation with larger numbers at multiple institutions Objective : Continuous venovenous hemofiltration ( CVVH ) is used for renal replacement and fluid management in critically ill children . A previous small study suggested that survival was associated with less percent fluid overload ( % FO ) in the intensive care unit ( ICU ) before hemofiltration . We review ed our experience with a large series of pediatric CVVH patients to evaluate factors associated with outcome . Design : Retrospective chart review . Setting : Tertiary children ’s hospital . Patients :  CVVH pediatric ICU patients from November 1997 to January 2003 . Interventions : None . Measurements and Main Results : % FO was defined as total fluid input minus output ( up to 7 days before CVVH for both hospital stay and ICU stay ) divided by body weight . One hundred thirteen patients received CVVH ; 69 survived ( 61 % ) . Multiple organ dysfunction syndrome ( MODS ) was present in 103 patients ; 59 survived ( 57 % ) . Median patient age was 9.6 yrs ( 25th , 75th percentile : 2.5 , 14.3 ) .  Median % FO was significantly lower in survivors vs. nonsurvivors for all patients ( 7.8 % [ 2.0 , 16.7 ] vs. 15.1 % [ 4.9 , 25.9 ] ; p = .02 ] and in patients with ≥3-organ MODS ( 9.2 % [ 5.1,16.7 ] vs. 15.5 % [ 8.3 , 28.6 ] ; p = .01 ) . The Pediatric Risk of Mortality Score III at CVVH initiation also was associated with survival in these groups , but by multivariate analysis , % FO was independently associated with survival in patients with ≥3-organ MODS ( p = .01 ) . Conclusions : Survival in critically ill children receiving CVVH in this large series was higher than in previous reports . CVVH survival may be associated with less % FO in patients with ≥3-organ MODS . Prospect i ve studies are necessary to determine whether earlier use of CVVH to control fluid overload in critically ill children can improve survival Objective : To evaluate the applicability , tolerance , and efficacy of a closed-loop protocol to wean children from mechanical ventilation . Design : Prospect i ve single-center pilot study . Setting : Tertiary care university hospital . Patients : Twenty mechanically ventilated children aged between 1 and 17 yrs , with a body weight ≥10 kg , no inotropes , and no heavy sedation . Interventions : Patients were weaned in pressure support mode by a closed-loop computerized protocol ( closed-loop protocol ) that interprets clinical data in real time and controls pressure support levels . Measurements and Main Results : The closed-loop protocol applicability and tolerance were evaluated . The efficacy of this protocol was evaluated by comparing the duration of mechanical ventilation with a historical group of 20 patients weaned with a clinician-decision protocol . The closed-loop protocol successfully decreased pressure support ventilation in 16 children , recommended separation from the ventilator in 14 children , and did not cause any serious adverse events . Mechanical ventilation duration was 5.1 ± 4.2 days in the closed-loop group and 6.7 ± 11.5 days ( mean ± sd ) in the clinician-decision group ( p = .33 ) with no difference in the need for reintubation or noninvasive mechanical ventilation ( one of 20 and four of 20 , respectively ; p = .20 ) . Conclusions : A closed-loop protocol was successfully used to wean children from mechanical ventilation . Further studies are required to assess the impact of this novel therapeutic strategy on the length of mechanical ventilation Several variables are recommended for identifying if a patient is ready for a trial of weaning from mechanical ventilation , but there is no agreement as to whether monitoring any variable during the trial enhances patient management . To determine whether repeated measurements of esophageal pressure throughout a trial are more reliable than measurements of esophageal pressure or frequency-to-VT ratio during the first minute of the trial , we studied 60 patients . A trend index that quantified esophageal pressure swings over time was more reliable than the first-minute measurements : sensitivity , 0.91 , and specificity , 0.89 . Area under receiver operating characteristic curve for trend index ( 0.94 ) was greater than for first-minute measurement of esophageal pressure ( 0.44 , p < 0.05 ) and tended to be greater than that for frequency-to-VT ratio ( 0.78 , p = 0.13 ) . The likelihood ratio was highest for the trend index ( 8.2 , p < 0.05 ) . The advantage of the trend index may be related to the progressive increase in esophageal pressure throughout a failed weaning trial , whereas breathing pattern changed little after 2 minutes of spontaneous breathing . In conclusion , continuous monitoring of esophageal pressure swings during a spontaneous breathing trial provides additional guidance in patient management over tests used for deciding when to initiate weaning BACKGROUND Variability and logistic complexity of mechanical ventilatory support of acute respiratory distress syndrome , and need to st and ardize care among all clinicians and patients , led University of Utah/LDS Hospital physicians , nurses , and engineers to develop a comprehensive computerized protocol . This bedside decision support system was the basis of a multicenter clinical trial ( 1993 - 1998 ) that showed ability to export a computerized protocol to other sites and improved efficacy with computer- versus physician-directed ventilatory support . The Memorial Hermann Hospital Shock Trauma intensive care unit ( ICU ) ( Houston , TX ; a Level I trauma center and teaching affiliate of The University of Texas Houston Medical School ) served as one of the 10 trial sites and recruited two thirds of the trauma patients . Results from the trauma patient subgroup at this site are reported to answer three questions : Can a computerized protocol be successfully exported to a trauma ICU ? Was ventilator management different between study groups ? Was patient outcome affected ? METHODS Sixty-seven trauma patients were r and omized at the Memorial Hermann Shock Trauma ICU site . " Protocol " assigned patients had  ventilatory support directed by the bedside respiratory therapist using the computerized protocol . " Non protocol " patients were managed by physician orders . RESULTS Of the 67 trauma patients r and omized , 33 were protocol ( age 40 + /- 3 ; Injury Severity Score [ ISS ] 26 + /- 3 ; 73 % blunt ) and 34 were non protocol ( age 38 + /- 2 ; ISS 25 + /- 2 ; 76 % blunt ) . For the protocol group , the computerized protocol was used 96 % of the time of ventilatory support and 95 % of computer-generated instructions were followed by the bedside respiratory therapist . Outcome measures ( i.e. , survival , ICU length of stay , morbidity , and barotrauma ) were not significantly different between groups . Fio2 > or = 0.6 and Pplateau > or = 35 cm H2O exposures were less for the protocol group . CONCLUSION A computerized protocol for bedside decision support was successfully exported to a trauma center , and effectively st and ardized mechanical ventilatory support of trauma-induced acute respiratory distress syndrome without adverse effect on patient outcome Previous studies have suggested that the early application of positive end-expiratory pressure ( PEEP ) reduces the incidence of the adult respiratory-distress syndrome . We r and omly assigned 92 patients with a known risk for this syndrome to receive mechanical ventilation either without PEEP ( control ) or with early PEEP at 8 cm H2O . These therapies continued for 72 hours unless respiratory distress developed or arterial oxygen tension was above 140 ( fractional inspired oxygen concentration , 0.5 ) at 24 hours or later and remained at that level after removal of PEEP . The study was design ed to have an 80 per cent probability of detecting a 60 per cent reduction in the incidence of the syndrome . The treatment groups were comparable in age , severity of injury , number and type of risk factors for adult respiratory-distress syndrome , and initial oxygenation . The syndrome developed in 11 of 44 patients given early PEEP  ( 25 per cent ) and in 13 of 48 control patients ( 27 per cent ) . The incidence of atelectasis , pneumonia , and barotrauma was the same in both groups , as was mortality . We found that the early application of PEEP at 8 cm H2O in high-risk patients had no effect on the incidence of the adult respiratory-distress syndrome or other , associated complications OBJECTIVE To report our experience with cuffed endotracheal tubes ( ETT ) in a large cohort of critically ill children . Study design We prospect ively collected data over a 1-year period concerning long-term intubation on 860 critically ill children admitted to our intensive care unit . Tube sizes were dictated by the modified Cole formula for uncuffed ETT ( age [y]/4 + 4 mm ID ) and chosen one-half size less for cuffed ETT .  Cuff pressure was regularly monitored to maintain a small leak at peak inspiratory pressure . The choice of ETT was made by the physician responsible for the initial airway management . RESULTS There were 597 patients in the first 5 years of life , with 210 having cuffed ETT . There were no significant differences in the use of racemic epinephrine for postextubation subglottic edema , the rate of successful extubation or the need for tracheotomy between those with cuffed and uncuffed ETT in any age group . CONCLUSIONS Our data suggest that the traditional teaching in pediatric anesthesia and intensive care , including current pediatric life support recommendations , need to be review ed for children to benefit from the advantages of modern low-pressure cuffed ETT during critical illnesses All patients intubated in the neonatal ( NICU ) and pediatric ( PICU ) ICUs over a 3-yr period were evaluated prospect ively to determine the incidence of accidental extubation ( AE ) and contributing factors . Two thous and two hundred patients ( age range 26 wk gestation to 18 yr ) were intubated for a total of 21,222 days . In the PICU and NICU , a total of 153 patients experienced 195 AE . The PICU had 113 AE in 1,388 subunit for a rate of 1.15 AE/100 intubated days . The NICU had 82 AE in 812 intubated patients , a rate of 0.72 AE/100 intubated days . A review of factors contributing to AE showed the most critical to be : sedation not administered in the 2 h before AE ( 65 % ) , the lack of two-point or more restraints ( 58 % ) , and the performance of a patient procedure at the bedside ( 49 % ) . One death occurred as an indirect consequence of AE . The data are being reported as a function of number of days intubated in an attempt to st and ardize reporting techniques . The use of st and ardized reporting and the identification of high-risk factors may be useful for education and modification of patient care practice s. ( Crit Care Med 1990 ; 18:163 Objective To vali date predictors of extubation success and failure in mechanically ventilated infants and children by using bedside measures of respiratory function . Design Prospect i ve , descriptive study . Setting A university-affiliated children ’s hospital with a 51-bed critical care area . Patients All infants and children who were mechanically ventilated for ≥24 hrs except neonates ≤37 wks gestation and patients with neuromuscular disease . Interventions None . Measurements and Methods Extubation failure was defined as reintubation within 48 hrs of extubation in the absence of upper airway obstruction . Failure rates were calculated for different ranges ( selected a priori ) of preextubation measures of breathing effort , ventilator support , respiratory mechanics , central inspiratory drive , and integrated indices useful in adults . Effort of spontaneous breathing was assessed by the respiratory rate st and ardized to age , the presence of retractions and paradoxic breathing , inspiratory pressure , maximal negative inspiratory pressure , ratio of inspiratory pressure to maximal negative inspiratory pressure , and tidal volume indexed to body weight of a spontaneous breath . Ventilator support was measured by Fio2 , mean airway pressure , oxygenation index , and the fraction of total minute ventilation provided by the ventilator . Respiratory mechanics was assessed by peak ventilatory inspiratory pressure and dynamic compliance . Central inspiratory drive was assessed by mean inspiratory flow . Frequency to tidal volume ratio and the CROP ( compliance , rate , oxygenation , and pressure ) indexed to body weight , the integrated indices useful in predicting extubation failure in adults , were also calculated . A regression test for a linear trend in proportions was performed with preselected ranges and the corresponding failure rates . The failure rates from this study ( validation group ) were compared to those published previously ( prediction group ) by the chi-square test for proportions . The distribution of categorical variables between groups was analyzed by using the chi-square test or the Fisher ’s exact test , and p < .05 was considered significant . Main Results The study involved 312 patients . There were no differences in any of the clinical characteristics between the prediction and validation groups . The reasons for reintubation were similar in both groups . Preextubation data were also similar between the two groups . There were no differences between the prediction and the validation groups in failure rates with different ranges . There were no differences in the failure rates for any of the cutoff values for peak ventilatory inspiratory pressure , mean airway pressure , Fio2 , oxygenation index , dynamic compliance , tidal volume indexed to body weight of a spontaneous breath , fraction of total minute ventilation provided by the ventilator , and mean inspiratory flow . Conclusions Bedside measures of respiratory function can predict extubation success and failure in infants and children . Both a low risk and a high risk of failure can be determined by using these measures . Integrated indices useful in adults do not reliably predict extubation success or failure in infants and children . Our study vali date s our previously published study Background Most children who undergo congenital heart surgery require postoperative mechanical ventilation . Failed extubation ( FE ) may result in physiologic instability , delay , or set back of the weaning process . FE is statistically associated with prolonged mechanical ventilation . Purpose We sought to identify frequency , pathogenesis , and risk factors for FE after congenital heart surgery in young children . Setting Pediatric intensive care unit . Patients Children ≤36 months of age who underwent congenital heart surgery in the period between January 1998 and July 1999 at our children ’s hospital . Measurements and Statistical Methods We performed a retrospective chart review . We defined reintubation within 24 hrs as an FE . Demographic , preoperative , intraoperative , and postoperative data were collected . A modified version of logistic regression , which accounts for lack of independence in data with multiple records per subject , was used to assess the impact of risk factors for FE . A forward selection process was used with p < .05 as the criterion for entry into the model . Estimated odds ratios ( EORs ) are reported with 95 % confidence intervals ( CI ) . The predictive ability of the final model was assessed by using area under the receiver operating characteristic curve . Main Results A total of 212 children ≤36 months of age underwent 230 congenital heart operations . Eleven children ( 5.2 % ) died perioperatively . After excluding patients who died , there were 219 surgeries among 202 patients ; 25.9 % ( 51 of 197 ) , 51.8 % ( 102 of 197 ) , and 72.6 % ( 143 of 197 ) of patients were successfully extubated by 12 , 24 , and 48 hrs , respectively . There were 22 cases in which an initial attempt at extubation failed at a median of 67.8 hrs ( range , 2.4–335.5 hrs ) . Five patients failed a subsequent attempt at extubation at a median of 189.5 hrs ( range , 115.8–602.5 hrs ) . The most common causes of initial FE were cardiac dysfunction ( n = 6 ) , lung disease ( n = 6 ) , and airway edema ( n = 3 ) . Risk factors for FE included pulmonary hypertension ( EOR , 38.7 ; 95 % CI , 2.9–25.8;p < .001 ) , Down syndrome ( EOR , 4.6 ; 95 % CI , 1.8–11.8;p = .002 ) , and deep hypothermic circulatory arrest ( EOR , 4.5 ; 95 % CI , 1.3–17.5;p = .018 ) . All were independent predictors of FE ( area under the curve , 0.837 ) . The strongest predictor was pulmonary hypertension , which when used alone to predict FE provided a sensitivity of 0.83 ( 95 % CI , 0.59–0.94 ) and a specificity of 0.75 ( 95 % CI , 0.68–0.80 ) . Conclusions Extubation fails after approximately 10 % of congenital heart surgery in young patients . Causes of FE are diverse . In our population , preoperative pulmonary hypertension , presence of a congenital syndrome , and intraoperative circulatory arrest are risk factors for FE . Prospect i ve validation of our predictive model with larger numbers and at multiple institutions would improve its utility Objective Unsuccessful extubation from mechanical ventilation increases mortality and morbidity . Therefore , the identification of an accurate predictor of successful extubation is desirable . This study was design ed to determine whether the results of easily performed respiratory measurements , particularly if reported as “ combined extubation ” indices , were better predictors of extubation failure in a pediatric population than were readily available clinical data . Design Prospect i ve observational study . Setting Tertiary pediatric intensive care unit . Patients All children who required mechanical ventilation for ≥24 hrs during a 12-month period and whose parents gave informed written consent . Interventions  Respiratory function measurements were made ( on average ) 7 hrs ( range , 0.2–25.0 hrs ) before extubation . Arterial blood gas results were obtained immediately before extubation . The values of each predictor associated with maximum sensitivity and specificity were determined , and the areas under receiver operator characteristic curves were compared to determine the most accurate predictor of successful extubation . Measurements and Main Results A total of 47 children ( mean age , 3.90 yrs ; range , 0.10–17.3 yrs ) were studied ; extubation failed in 7 . A low tidal volume ( < 7.5 mL/kg ) and a low minute volume ( < 250 mL/kg ) had the highest sensitivities ( 86 % and 71 % , respectively ) and specificities ( 61 % and 71 % , respectively ) in predicting extubation failure . The a/A ratio performed least well in predicting extubation failure ( area under the receiver operating characteristic curve , 0.51 ) . Conclusions Volume measurements during pediatric mechanical ventilation may facilitate successful extubation OBJECTIVE To examine medical outcomes associated with reintubation for extubation failure after discontinuation of mechanical ventilation . DESIGN Prospect i ve cohort study of consecutive intubated medical ICU patients who underwent a trial of extubation at a tertiary-care teaching hospital . The failed extubation group consisted of all patients reintubated within 72 h or within 7 days ( if continuous ICU care had been required ) of extubation . All others were considered to be successfully extubated . Study end points included hospital death vs survival , the number of days spent in the ICU and in the hospital after the onset of mechanical ventilation , the likelihood of requiring > or = 7 or > or = 14 days of ICU care after extubation , and the need for transfer to either a long-term care or rehabilitation facility among the survivors . RESULTS Of 289 intubated patients , 247 ( 85 % ) were successfully extubated , and 42 ( 15 % ) required reintubation for failed extubation ( time to reintubation 1.5+/-0.2 days ) . Reintubation for extubation failure result ed in 12 additional days of mechanical ventilation . When compared with successfully extubated patients , reintubated patients were more likely to die in the hospital ( 43 % vs 12 % ; p<0.0001 ) , spend more time in the ICU ( 21.2+/-2.8 days vs 4.5+/-0.6 days ; p<0.001 ) and in the hospital ( 30.5+/-3.3 days vs 16.3+/-1.2 days ; p<0.001 ) after extubation , and require transfer to a long-term care or rehabilitation facility ( 38 % vs 21 % ; p<0.05 ) . Using multiple logistic regression , extubation failure was an independent predictor for death and the need for transfer to a long-term care facility . Compared with those successfully extubated , patients who failed extubation were seven times ( p<0.0001 ) more likely to die , 31 times ( p<0.0001 ) more likely to spend > or = 14 days in the ICU after extubation , and six times ( p<0.001 ) more likely to need transfer to a long-term care or rehabilitation facility if they survived . CONCLUSION After adjusting for severity of illness and comorbid conditions , extubation failure had a significant independent association with increased risk for death , prolonged ICU stay , and transfer to a long-term care or rehabilitation facility . Extubation failure may serve as an additional independent marker of severity of illness . Alternatively , poor outcomes may be etiologically related to extubation failure . If the latter proves to be the case , identifying patients at risk for poor outcomes from extubation failure and instituting alternative care practice s may reduce mortality , duration of ICU stay , and need for transfer to a long-term care facility
OBJECTIVE A systematic review of weaning and extubation for pediatric patients on mechanical ventilation .
CONCLUSIONS Despite the importance of minimizing time on mechanical ventilation , only limited guidance on weaning and extubation is available from the pediatric literature .
A significant proportion of patients being evaluated for weaning are actually ready for extubation , suggesting that weaning is often not considered early enough in the course of ventilation .
Indications for extubation are even less clear , although a trial of spontaneous breathing would seem a prerequisite .