Intraoperative ventilation: incidence and risk factors for receiving large tidal volumes during general anesthesia Mechanical ventilation strategies and inflammatory responses to cardiac surgery: a prospective randomized clinical trial Impact of intraoperative lung-protective interventions in patients undergoing lung cancer surgery The Pulmonary Immune Effects of Mechanical Ventilation in Patients Undergoing Thoracic Surgery Effect of low tidal volume ventilation on atelectasis in patients during general anesthesia: a computed tomographic scan. High Tidal Volumes in Mechanically Ventilated Patients Increase Organ Dysfunction after Cardiac Surgery The impact of tidal volume on pulmonary complications following minimally invasive esophagectomy: a randomized and controlled study. [Effects of the lung protective ventilatory strategy on proinflammatory cytokine release during one-lung ventilation]. Mechanical Ventilation with Lower Tidal Volumes and Positive End-expiratory Pressure Prevents Pulmonary Inflammation in Patients without Preexisting Lung Injury Prediction of Postoperative Pulmonary Complications in a Population-based Surgical Cohort Protective Ventilation Influences Systemic Inflammation after Esophagectomy: A Randomized Controlled Study The effect of low versus high tidal volume ventilation on inflammatory markers in healthy individuals undergoing posterior spine fusion in the prone position: a randomized controlled trial. The Effects of Different Ventilatory Settings on Pulmonary and Systemic Inflammatory Responses During Major Surgery A trial of intraoperative low-tidal-volume ventilation in abdominal surgery. Protective ventilation attenuates postoperative pulmonary dysfunction in patients undergoing cardiopulmonary bypass. Mechanical ventilation affects inflammatory mediators in patients undergoing cardiopulmonary bypass for cardiac surgery: a randomized clinical trial.
Background There is a growing concern of the potential injurious role of ventilatory over-distention in patients without lung injury . No formal guidelines exist for intraoperative ventilation setting s , but the use of tidal volumes ( VT ) under 10 mL/kg predicted body weight ( PBW ) has been recommended in healthy patients . We explored the incidence and risk factors for receiving large tidal volumes ( VT > 10 mL/kg PBW ) . Methods We performed a cross-sectional analysis of our prospect ively collected perioperative electronic data base for current intraoperative ventilation practice s and risk factors for receiving large tidal volumes ( VT > 10 mL/kg PBW ) . We included all adults undergoing prolonged ( ≥ 4 h ) elective abdominal surgery and collected demographic , preoperative ( comorbidities ) , intraoperative ( i.e. ventilatory setting s , fluid administration ) and postoperative ( outcomes ) information . We compared patients receiving exhaled tidal volumes > 10 mL/kg PBW with those that received 8 - 10 or < 8 mL/kg PBW with univariate and logistic regression analyses . Results Ventilatory setting s were non-uniform in the 429 adults included in the analysis . 17.5 % of all patients received VT > 10 mL/kg PBW . 34.0 % of all obese patients ( body mass index , BMI , ≥ 30 ) , 51 % of all patients with a height < 165 cm , and 34.6 % of all female patients received VT > 10 mL/kg PBW . Conclusions Ventilation with VT > 10 mL/kg PBW is still common , although poor correlation with PBW suggests it may be unintentional . BMI ≥ 30 , female gender and height < 165 cm may predispose to receive large tidal volumes during general anesthesia . Further awareness of patients ' height and PBW is needed to improve intraoperative ventilation practice s. The impact on clinical outcome needs confirmation Objective To examine whether postoperative mechanical ventilation with lower tidal volumes ( VT ) has protective effects on inflammatory responses induced by  cardiopulmonary bypass ( CPB )  surgery in smokers and nonsmokers . Design and setting Prospect i ve , r and omized , controlled clinical trial in the intensive care unit of a university hospital . Patients and participants We examined 44 patients ( 22 smokers , 22 nonsmokers ) immediately after uncomplicated CPB surgery . Interventions Ventilation was applied for 6 h with either VT of either 6 or 12 ml/kg ideal body weight . Measurements and results The time course of serum tumor necrosis factor ( TNF ) α , interleukin ( IL ) 6 , and IL-8 determined 0 , 2 , 4 , and 6 h after r and omization did not differ significantly between the ventilatory strategies . By contrast , in bronchoalveolar lavage fluids sample d after 6 h only TNF-α levels were significantly higher in the high VT group than the low VT group ( 50±111 pg/ml vs. 1±7 pg/ml ) . IL-6 and IL-8 concentrations did not differ between groups . Subgroup analysis of patients with serum TNF-α level higher than 0 pg/ml after surgery revealed lower TNF-α serum levels during lower VT ventilation . All observed effects were small , independent of patients ’ history of smoking , and were not correlated with duration of ventilation and ICU stay . Conclusions Ventilation with lower VT had no or only minor effect on systemic and pulmonary inflammatory responses in patients with healthy lungs after uncomplicated CPB surgery . Our data do not suggest a clinical benefit of using low VT ventilation in these selected patients Introduction In lung cancer surgery , large tidal volume and elevated inspiratory pressure are known risk factors of acute lung ( ALI ) . Mechanical ventilation with low tidal volume has been shown to attenuate lung injuries in critically ill patients . In the current study , we assessed the impact of a protective lung ventilation ( PLV ) protocol in patients undergoing lung cancer resection . Methods We performed a secondary analysis of an observational cohort . Demographic , surgical , clinical and outcome data were prospect ively collected over a 10-year period . The PLV protocol consisted of small tidal volume , limiting maximal pressure ventilation and adding end-expiratory positive pressure along with recruitment maneuvers . Multivariate analysis with logistic regression was performed and data were compared before and after implementation of the PLV protocol : from 1998 to 2003 ( historical group , n = 533 ) and from 2003 to 2008 ( protocol group , n = 558 ) . Results Baseline patient characteristics were similar in the two cohorts , except for a higher cardiovascular risk profile in the intervention group . During one-lung ventilation , protocol -managed patients had lower tidal volume ( 5.3 ± 1.1 vs. 7.1 ± 1.2 ml/kg in historical controls , P = 0.013 ) and higher dynamic compliance ( 45 ± 8 vs. 32 ± 7 ml/cmH2O , P = 0.011 ) . After implementing PLV , there was a decreased incidence of acute lung injury ( from 3.7 % to 0.9 % , P < 0.01 ) and atelectasis ( from 8.8 to 5.0 , P = 0.018 ) , fewer admissions to the intensive care unit ( from 9.4 % vs. 2.5 % , P < 0.001 ) and shorter hospital stay ( from 14.5 ± 3.3 vs. 11.8 ± 4.1 , P < 0.01 ) . When adjusted for baseline characteristics , implementation of the open-lung protocol was associated with a reduced risk of acute lung injury ( adjusted odds ratio of 0.34 with 95 % confidence interval of 0.23 to 0.75 ; P = 0.002 ) . Conclusions Implementing an intraoperative PLV protocol in patients undergoing lung cancer resection was associated with improved postoperative respiratory outcomes as evidence by significantly reduced incidences of acute lung injury and atelectasis along with reduced utilization of intensive care unit re sources Mechanical ventilation ( MV ) may induce an inflammatory alveolar response .  One-lung ventilation ( OLV ) with tidal volumes ( Vt ) as used during two-lung ventilation is a suggested algorithm but may impose mechanical stress of the dependent lung and potentially aggravate alveolar mediator release . We studied whether ventilation with different Vt modifies pulmonary immune function , hemodynamics , and gas exchange .  Thirty-two patients undergoing open thoracic surgery were r and omized to receive either MV with Vt = 10 mL/kg ( n = 16 ) or Vt = 5 mL/kg ( n = 16 ) adjusted to normal Paco2 during and after OLV . Fiberoptic bronchoalveolar lavage of the ventilated lung was performed , and cells , protein , tumor necrosis factor (TNF)-&agr ; , interleukin (IL)-8 , soluble intercellular adhesion molecule (sICAM)-1 , IL-10 , and elastase were determined in the bronchoalveolar lavage . Data were analyzed by parametric or nonparametric tests , as indicated . In all patients , an increase of proinflammatory variables was found . The time courses of intra-alveolar cells , protein , albumin , IL-8 , elastase , and IL-10 did not differ between the groups after OLV and postoperatively . TNF-&agr ; ( 8.4 versus 5.0 & mgr;g/mL ) and sICAM-1 ( 52.7 versus 27.5 & mgr;g/mL ) concentrations were significantly smaller after OLV with Vt = 5 mL/kg . These results indicate that MV may induce epithelial damage and a proinflammatory response in the ventilated lung . Reduction of tidal volume during OLV may reduce alveolar concentrations of TNF-&agr ; and of sICAM-1 STUDY OBJECTIVE To determine whether low tidal ventilation in patients without lung injury results in an increase in the amount of atelectasis and a further impairment of gas exchange during general anesthesia . DESIGN R and omized , single-blind study . SETTING University hospital . PATIENTS 16 adult , ASA physical status I and II patients , who were scheduled for elective excision of intracranial lesion . INTERVENTIONS Patients were r and omly allocated to one of two groups : traditional tidal volume ( V(T ) ) ventilation group ( V(T ) , 10 mL/kg ) and low V(T ) ventilation group ( V(T ) , 6 mL/kg ) after the first computed tomographic ( CT ) scan . MEASUREMENTS AND MAIN RESULTS Atelectasis , as determined by CT and arterial blood gas analysis , was measured before induction , after tracheal intubation , and at the end of operation . After tracheal intubation , CT scan showed atelectasis in both groups . The mean atelectasis area was 4.25 + /- 2.05 cm(2 ) ( 3.32 % + /- 1.94 % ) in the traditional V(T ) ventilation group and 5.56 + /- 3.21 cm(2 ) ( 4.19 % + /- 2.31 % ) in the low V(T ) ventilation group . At the end of operation , there was no significant increase in the amount of atelectasis within the two groups . Arterial blood gas analysis showed no differences after tracheal intubation or at the end of operation in either group . CONCLUSION Ventilation using low V(T)s does not cause more pulmonary collapse than mechanical ventilation using st and ard V(T)s Background : High tidal volumes in patients with acute respiratory distress syndrome and acute lung injury lead to ventilator-induced lung injury and increased mortality . We evaluated the impact of tidal volumes on cardiac surgery outcomes . Methods : We examined prospect ively recorded data from 3,434 consecutive adult patients who underwent cardiac surgery .  Three groups of patients were defined based on the tidal volume delivered on arrival at the intensive care unit : ( 1 ) low : below 10 , ( 2 ) traditional : 10–12 , and ( 3 ) high : more than 12 ml/kg of predicted body weight . We assessed risk factors for three types of organ failure ( prolonged mechanical ventilation , hemodynamic instability , and renal failure ) and a prolonged stay in the intensive care unit . Results : The mean tidal volume/actual weight was 9.2 ml/kg , and the tidal volume/predicted body weight was 11.5 ml/kg . Low , traditional , and high tidal volumes were used in 724 ( 21.1 % ) , 1567 ( 45.6 % ) , and 1,143 patients ( 33.3 % ) , respectively . Independent risks factors for high tidal volumes were body mass index of 30 or more ( odds ratio [ OR ] 6.25 ; CI : 5.26–7.42 ; P < 0.001 ) and female sex ( OR 4.33 ; CI : 3.64–5.15 ; P < 0.001 ) . In the multivariate analysis , high and traditional tidal volumes were independent risk factors for organ failure , multiple organ failure , and prolonged stay in the intensive care unit . Organ failures were associated with increased intensive care unit stay , hospital mortality , and long-term mortality . Conclusion : Tidal volumes of more than 10 ml/kg are risk factors for organ failure and prolonged intensive care unit stay after cardiac surgery . Women and obese patients are particularly at risk of being ventilated with injurious tidal volumes BACKGROUND Minimally invasive esophagectomy ( MIE ) has been advantageous for lowering pulmonary complications compared with open approaches.(1 ) However , pulmonary complications remain the most common morbidity after surgical resection of esophageal cancer.(2,3 ) The aim of this prospect i ve , r and omized , controlled , clinical trial was design ed to see whether low tidal volume ( VT ) could further minimize pulmonary complications after MIE . METHODS Between June 2011 and July 2012 , a total of 101 patients who underwent MIE received left-lung ventilation during thoracoscopic esophagectomy .  All patients received left-lung ventilation during thoracoscopic esophagectomy . Patients were r and omly assigned to a low VT ( 5 mL/kg + 5 cm H2O positive end-expiratory pressure ) preserved ventilation ( PV ) group ( n = 53 ) and a conventional VT ( 8 mL/kg ) controlled ventilation ( CV ) group ( n = 48 ) in the thoracic stage . Alveolar lavage fluid was harvested from the ventilated lung at intubation and at 18 hours after surgery for analysis of interleukin (IL)-1ß , IL-6 , and IL-8 levels . Clinical characteristics , including patient demographics , operation features , and changes in oxygenation index , were recorded and analyzed . Pulmonary complications were identified and statistically compared between the 2 groups . RESULTS The clinical characteristics and operation features were comparable between the 2 groups . IL-1ß , IL-6 , and IL-8 expressions in preoperative alveolar lavage fluid were similar between the 2 groups . Significantly lower IL expressions were observed in the PV group than those in the CV group at 18 hours after MIE ( IL-1ß , 25.42 ± 31.01 vs 94.96 ± 118.24 pg/mL ; IL-6 , 30.86 ± 75.78 vs 92.99 ± 72.90 pg/mL ; IL-8 , 258.75 ± 188.24 vs 403.95 ± 151.44 pg/mL ; all P < .05 ) . The 18-hour postoperative oxygenation index was lower in the CV group than that in the PV group ( 292.85 ± 28.74 vs 326.35 ± 34.43 ; P = .046 ) . Pulmonary complications were observed in 18 cases of our series , occurring more frequently on the ventilation side ( right , 6 cases ; and left , 12 cases ) . All patients were cured by conservative therapy without severe sequelae . The occurrence of pulmonary complications in the PV group was lower than that in the CV group ( 9.43 % vs 27.08 % ; P = .021 ) . CONCLUSIONS Lung injury due to intraoperative single-lung ventilation may contribute to pulmonary complications after MIE . Low VT ventilation could decrease ventilation-associated lung inflammation , thus minimizing pulmonary complications after MIE . Further studies , based on a larger volume of population s , are required to confirm these findings BACKGROUND & OBJECTIVE A prolonged period of one-lung ventilation(OLV ) is required during thoracic surgery and this may activate cytokine release and cause lung inflammatory response . The lung protective ventilatory strategy has reduced lung and systemic cytokine release and achieved remarkable curative effect in patients with acute respiratory distress syndrome ( ARDS ) . This study was to investigate the effect of the lung protective ventilatory strategy on proinflammatory cytokine release during OLV in patients underwent thoracic surgery . METHODS Forty patients underwent esophagectomy were r and omly divided into conventional ventilation ( CV ) group ( n=20 ) and protective ventilation ( PV ) group ( n=20 ) . In CV group , all patients received two-lung ventilation ( TLV ) and OLV with a tidal volume ( VT ) of 10 mL/kg and an inspiration/expiration ratio ( I/E ) of 1:1.5 . In PV group , all patients received TLV with a VT of 10 mL/kg and an I/E ratio of 1:1.5 , and received OLV with a VT of 5 - 6 mL/kg and an I/E ratio of 1:1 , along with positive end-expiratory pressure ( PEEP ) preset at 3 - 5 cm H2O . Blood sample s of 3 mL were extracted at three time courses , which were after tracheal intubation ( T1 ) , 120 min after OLV ( T2 ) and 24 h after operation ( T3 ) , to analyze concentrations of interleukin (IL)-6 and IL-8 in the two groups . Values of airway peak pressure ( Ppeak ) , airway plateau pressure ( Pplat ) , and airway resistance(Raw)were also recorded using side stream spirometry . RESULTS In CV group , concentrations of IL-6 and IL-8 at T2 [ ( 269.4+/-57.2 ) ng/L , ( 180.8+/-35.0 ) ng/L ] and T3[(335.8+/-98.7 ) ng/L,(178.5+/-18.3 ) ng/L ] were significantly increased as compared with those at T1 [ ( 17.0+/-5.4 ) ng/L,(18.2+/-2.8 ) ng/L](P<0.05 ) . In PV group , concentrations of IL-6 and IL-8 at T2 [ ( 209.3+/-55.7 ) ng/L ] , ( 115.3+/-71.5 ) ng/L ] and T3 [ ( 278.2+/-100.8 ) ng/L,(124.2+/-40.1 ) ng/L ] were significantly increased as compared with those at T1[(20.0+/-7.1 ) ng/L,(15.3+/-3.6 ) ng/L ] ( P<0.05 ) . Concentrations of IL-6 and IL-8 at T2 and T3 were significantly higher in CV group than in PV group ( P<0.05 ) . Ppeak , Pplat and Raw at T2 were significantly higher in CV group [ ( 33.6+/-4.6 cmH2O,(21.5+/-3.1 ) cmH2O , ( 26.3+/-2.1 ) cmH2O.L(-1).S(-1 ) ] than in PV group [ ( 26.7+/-3.5 ) cmH2O , ( 12.4+/-2.1 ) cmH2O , ( 18.3+/-2.3 ) cmH2O.L(-1).S(-1)](P<0.05 ) . CONCLUSIONS Concentrations of IL-6 and IL-8 are increased during and after OLV in thoracic surgery . The lung protective ventilatory strategy can reduce the airway pressure and airway resistance during OLV , decrease the release of IL-6 and IL-8 , and inhibit lung inflammatory responses during OLV and postoperatively Background : Mechanical ventilation with high tidal volumes aggravates lung injury in patients with acute lung injury or acute respiratory distress syndrome . The authors sought to determine the effects of short-term mechanical ventilation on local inflammatory responses in patients without preexisting lung injury . Methods : Patients scheduled to undergo an elective surgical procedure ( lasting ≥5 h ) were r and omly assigned to mechanical ventilation with either higher tidal volumes of 12 ml/kg ideal body weight and no positive end-expiratory pressure ( PEEP ) or lower tidal volumes of 6 ml/kg and 10 cm H2O PEEP . After induction of anesthesia and 5 h thereafter , bronchoalveolar lavage fluid and /or blood was investigated for polymorphonuclear cell influx , changes in levels of inflammatory markers , and nucleosomes . Results : Mechanical ventilation with lower tidal volumes and PEEP ( n = 21 ) attenuated the increase of pulmonary levels of interleukin (IL)-8 , myeloperoxidase , and elastase as seen with higher tidal volumes and no PEEP ( n = 19 ) . Only for myeloperoxidase , a difference was found between the two ventilation strategies after 5 h of mechanical ventilation ( P < 0.01 ) . Levels of tumor necrosis factor α , IL-1α , IL-1β , IL-6 , macrophage inflammatory protein 1α , and macrophage inflammatory protein 1β in the bronchoalveolar lavage fluid were not affected by mechanical ventilation . Plasma levels of IL-6 and IL-8 increased with mechanical ventilation , but there were no differences between the two ventilation groups . Conclusion : The use of lower tidal volumes and PEEP may limit pulmonary inflammation in mechanically ventilated patients without preexisting lung injury . The specific contribution of both lower tidal volumes and PEEP on the protective effects of the lung should be further investigated Background : Current knowledge of the risk for  postoperative pulmonary complications ( PPCs  ) rests on studies that narrowly selected patients and procedures . Hypothesizing that PPC occurrence could be predicted from a reduced set of perioperative variables , we aim ed to develop a predictive index for a broad surgical population . Methods : Patients undergoing surgical procedures given general , neuraxial , or regional anesthesia in 59 hospitals were r and omly selected for this prospect i ve , multicenter study . The main outcome was the development of at least one of the following : respiratory infection , respiratory failure , bronchospasm , atelectasis , pleural effusion , pneumothorax , or aspiration pneumonitis . The cohort was r and omly divided into a development sub sample to construct a logistic regression model and a validation sub sample . A PPC predictive index was constructed . Results : Of 2,464 patients studied , 252 events were observed in 123 ( 5 % ) . Thirty-day mortality was higher in patients with a PPC ( 19.5 % ; 95 % [ CI ] , 12.5–26.5 % ) than in those without a PPC ( 0.5 % ; 95 % CI , 0.2–0.8 % ) . Regression modeling identified seven independent risk factors : low preoperative arterial oxygen saturation , acute respiratory infection during the previous month , age , preoperative anemia , upper abdominal or intrathoracic surgery , surgical duration of at least 2 h , and emergency surgery . The area under the receiver operating characteristic curve was 90 % ( 95 % CI , 85–94 % ) for the development sub sample and 88 % ( 95 % CI , 84–93 % ) for the validation sub sample . Conclusion : The risk index based on seven objective , easily assessed factors has excellent discriminative ability . The index can be used to assess individual risk of PPC and focus further research on measures to improve patient care Background : Esophagectomy induces a systemic inflammatory response whose extent has been recognized as a predictive factor of postoperative respiratory morbidity . The aim of this study was to determine the effectiveness of a protective ventilatory strategy to reduce systemic inflammation in patients undergoing esophagectomy . Methods : The authors prospect ively investigated 52 patients undergoing planned esophagectomy for cancer . Patients were r and omly assigned to a conventional ventilation strategy ( n = 26 ; tidal volume of 9 ml/kg during two-lung and one-lung ventilation ; no positive end-expiratory pressure ) or a protective ventilation strategy ( n = 26 ; tidal volume of 9 ml/kg during two-lung ventilation , reduced to 5 ml/kg during one-lung ventilation ; positive end-expiratory pressure 5 cm H2O throughout the operative time ) . Results : Plasmatic levels of interleukin (IL)-1&bgr ; , IL-6 , IL-8 , and tumor necrosis factor & agr ; were measured perioperatively and postoperatively . Pulmonary function and postoperative evolution were also evaluated . Patients who received protective strategy had lower blood levels of IL-1&bgr ; , IL-6 , and IL-8 at the end of one-lung ventilation ( 0.24 [ 0.15–0.40 ] vs. 0.56 [ 0.38–0.89 ] pg/ml , P < 0.001 ; 91 [ 61–117 ] vs. 189 [ 127–294 ] pg/ml , P < 0.001 ; and 30 [ 22–45 ] vs. 49 [ 29–69 ] pg/ml , P < 0.05 , respectively ) and 18 h postoperatively ( 0.18 [ 0.13–0.30 ] vs. 0.43 [ 0.34–0.54 ] pg/ml , P < 0.001 ; 54 [ 36–89 ] vs. 116 [ 78–208 ] pg/ml , P < 0.001 ; 16 [ 11–24 ] vs. 35 [ 28–53 ] pg/ml , P < 0.001 , respectively ) . Protective strategy result ed in higher oxygen partial pressure to inspired oxygen fraction ratio during one-lung ventilation and 1 h postoperatively and in a reduction of postoperative mechanical ventilation duration ( 115 ± 38 vs. 171 ± 57 min , P < 0.001 ) . Conclusion : A protective ventilatory strategy decreases the proinflammatory systemic response after esophagectomy , improves lung function , and results in earlier extubation STUDY OBJECTIVE To evaluate the effect of ventilation strategy on markers of inflammation in patients undergoing spine surgery in the prone position . DESIGN R and omized controlled trial . SETTING University-affiliated teaching hospital . PATIENTS 26 ASA physical status 1 and 2 patients scheduled for elective primary lumbar decompression and fusion in the prone position . INTERVENTIONS Patients were r and omized to receive mechanical ventilation  with either a tidal volume ( V(T ) ) of 12 mL/kg ideal body weight with zero positive end-expiratory pressure ( PEEP ) or V(T ) of 6 mL/kg ideal body weight with PEEP of 8 cm H(2)O. MEASUREMENTS Plasma levels of interleukin (IL)-6 and IL-8 were determined at the beginning of ventilation and at 6 and 12 hours later . Urinary levels of desmosine were determined at the beginning of ventilation and on postoperative days 1 and 3 . MAIN RESULTS A significant increase in IL-6 , IL-8 , and urine desmosine levels was noted over time compared with baseline ( P < 0.01 ) . However , no significant difference in the levels of markers was seen between the groups at any time point when controlling for demographics , ASA physical status , body mass index , duration of ventilation , or estimated blood loss . CONCLUSIONS Although markers of inflammation are increased after posterior spine fusion surgery , ventilation strategy has minimal impact on markers of systemic inflammation Mechanical ventilation with high tidal volumes ( VT ) and zero or low positive end-expiratory pressure increased mediator release to inflammatory stimuli or acute lung injury . We studied whether mechanical ventilation modifies the inflammatory responses during major thoracic or abdominal surgery . Sixty-four patients undergoing elective thoracotomy ( n = 34 ) or laparotomy ( n = 30 ) were r and omized to receive either mechanical ventilation with VT = 12 or 15 mL/kg ideal body weight , respectively , and zero end-expiratory pressure , or VT = 6 mL/kg ideal body weight with positive end-expiratory pressure of 10 cm H2O . In 62 patients who completed the study , arterial oxygena- tion was not different between groups . Tumor necrosis factor , interleukin (IL)-1 , IL-6 , IL-8 , IL-10 , and IL-12 were determined by cytometric bead array in plasma after 0 , 1 , 2 , and 3 h and in tracheal aspirates after 3 h of mechanical ventilation . Data were log-transformed and analyzed using parametric or nonparametric tests , as indicated . All plasma mediators increased more during abdominal than during thoracic surgery , although the differences were small . However , neither time course nor concentrations of pulmonary or systemic mediators differed between the two ventilatory setting s. Our data suggest that the ventilatory setting s we studied do not affect inflammatory reactions during major surgery within 3 BACKGROUND Lung-protective ventilation with the use of low tidal volumes and positive end-expiratory pressure is considered best practice in the care of many critically ill patients . However , its role in anesthetized patients undergoing major surgery is not known . METHODS In this multicenter , double-blind , parallel-group trial , we r and omly assigned 400 adults at intermediate to high risk of pulmonary complications after major abdominal surgery to either nonprotective mechanical ventilation or a strategy of lung-protective ventilation . The primary outcome was a composite of major pulmonary and extrapulmonary complications occurring within the first 7 days after surgery . RESULTS The two intervention groups had similar characteristics at baseline . In the intention-to-treat analysis , the primary outcome occurred in 21 of 200 patients ( 10.5 % ) assigned to lung-protective ventilation , as compared with 55 of 200 ( 27.5 % ) assigned to nonprotective ventilation ( relative risk , 0.40 ; 95 % confidence interval [ CI ] , 0.24 to 0.68 ; P=0.001 ) . Over the 7-day postoperative period , 10 patients ( 5.0 % ) assigned to lung-protective ventilation required noninvasive ventilation or intubation for acute respiratory failure , as compared with 34 ( 17.0 % ) assigned to nonprotective ventilation ( relative risk , 0.29 ; 95 % CI , 0.14 to 0.61 ; P=0.001 ) . The length of the hospital stay was shorter among patients receiving lung-protective ventilation than among those receiving nonprotective ventilation ( mean difference , -2.45 days ; 95 % CI , -4.17 to -0.72 ; P=0.006 ) . CONCLUSIONS As compared with a practice of nonprotective mechanical ventilation , the use of a lung-protective ventilation strategy in intermediate-risk and high-risk patients undergoing major abdominal surgery was associated with improved clinical outcomes and reduced health care utilization . ( IMPROVE Clinical Trials.gov number , NCT01282996 . ) OBJECTIVE To ascertain if protective ventilation can attenuate the damaging postoperative pulmonary effects of cardiopulmonary bypass ( increases in airway pressure , decreases in lung compliance , and increases in shunt ) . DESIGN Prospect i ve , r and omized clinical trial . SETTING Single university hospital . PARTICIPANTS Twenty-five patients undergoing elective coronary artery bypass graft procedure and early extubation . INTERVENTIONS Thirteen patients received conventional mechanical ventilation ( CV ; respiratory rate , 8 breaths/min ; tidal volume , 12 mL/kg ; fraction of inspired oxygen [ FIO2 ] , 1.0 ; positive end-expiratory pressure [ PEEP ] , + 5 ) , and 12 patients received protective mechanical ventilation ( PV ; respiratory rate , 16 breaths/min ; tidal volume , 6 mL/kg ; FIO2 , 1.0 ; PEEP , + 5 ) . Perioperative anesthetic and surgical management were st and ardized . Various pulmonary parameters were determined twice perioperatively : 10 minutes after intubation and 60 minutes after arrival in the intensive care unit . MEASUREMENTS AND MAIN RESULTS The mean postoperative increase in peak airway pressure in group CV was significantly larger than the mean postoperative increase in peak airway pressure in group PV ( 7.1 v 2.4 cm H2O ; p < 0.001 ) . Group CV experienced significant postoperative increases in plateau airway pressure ( p = 0.007 ) , but group PV did not ( p = 0.644 ) . The mean postoperative decrease in dynamic lung compliance in group CV was significantly larger than the mean postoperative decrease in dynamic lung compliance in group PV ( 14.9 v 5.5 mL/cm H2O ; p = 0.002 ) . Group CV experienced significant postoperative decreases in static lung compliance ( p = 0.014 ) , but group PV did not ( p = 0.645 ) . Group CV experienced significant postoperative increases in shunt ( 15.5 % to 21.4 % ; p = 0.021 ) , but group PV did not ( 18.4 % to 21.2 % ; p = 0.265 ) . CONCLUSIONS Data indicate that protective ventilation decreases pulmonary damage caused by mechanical ventilation in normal and abnormal lungs . The results of this investigation indicate that protective ventilation may also help attenuate the postoperative pulmonary dysfunction ( increases in airway pressure , decreases in lung compliance , and increases in shunt ) commonly seen in patients after exposure to cardiopulmonary bypass OBJECTIVES Respiratory support for patients recovering from cardiopulmonary bypass and cardiac surgery uses large tidal volumes and a minimal level of positive end-expiratory pressure . Recent data indicate that these ventilator setting s might cause pulmonary and systemic inflammation in patients with acute lung injury . We examined the hypothesis that high tidal volumes and low levels of positive end-expiratory pressure might worsen the inflammatory response associated to cardiopulmonary bypass . METHODS Forty patients undergoing elective coronary artery bypass were r and omized to be ventilated after cardiopulmonary bypass disconnection  with high tidal volume/low positive end-expiratory pressure ( 10 - 12 mL/kg and 2 - 3 cm H2O , respectively ) or low tidal volume/high positive end-expiratory pressure ( 8 mL/kg and 10 cm H2O , respectively ) . Interleukin 6 and interleukin 8 levels were measured in the bronchoalveolar lavage fluid and plasma . Sample s were taken before sternotomy ( time 0 ) , immediately after cardiopulmonary bypass separation ( time 1 ) , and after 6 hours of mechanical ventilation ( time 2 ) . RESULTS Interleukin 6 and interleukin 8 levels in the bronchoalveolar lavage fluid and plasma significantly increased at time 1 in both groups but further increased at time 2 only in patients ventilated with high tidal volume/low positive end-expiratory pressure . Interleukin 6 and interleukin 8 levels in the bronchoalveolar lavage fluid and in the plasma at time 2 were higher with high tidal volume/low positive end-expiratory pressure than with low tidal volume/high positive end-expiratory pressure . CONCLUSION Mechanical ventilation might be a cofactor able to influence the inflammatory response after cardiac surgery
BACKGROUND Lung injury is a serious complication of surgery .
We did a systematic review and meta- analysis to assess whether incidence , morbidity , and in-hospital mortality associated with postoperative lung injury are affected by type of surgery and whether outcomes are dependent on type of ventilation .