you work in the neurological intensive care unit ( icu ) and you are managing a patient who suffered a subarachnoid bleed and , despite appropriate therapy , is left with significant neurological impairment . you have weaned the patient appropriately on the ventilator and you feel that they are strong enough to tolerate extubation . you worry that , given their severe neurological impairment , they may not be able to protect their airway upon extubation , and as such you consider the merits of tracheostomy .
luciana mascia , eleomore corno and pier paok terragni during the early phase after acute brain injury , patients with impaired consciousness may require mechanical ventilation to protect their airway , treatment for intracranial hypertension , and ventilatory support to treat pulmonary complications .
after the acute phase , and once satisfactory weaning parameters have been achieved , the patient 's impaired level of consciousness and inability to protect their airway represent strong reasons why extubation should be delayed .
these patients might benefit from continued intubation through prevention of aspiration and because of their limited ability to clear secretions , but it has been shown that prolonged intubation in traumatic brain injury is associated with a high incidence of pneumonia .
conversely , early tracheostomy after trauma reduces icu length of stay and number of ventilator days , and reduces the incidence of ventilator - associated pneumonia [ 3 - 5 ] .
koh and coworkers   confirmed that patients undergoing early elective tracheostomy had shorter icu stays than did patients who were given extubation trials before tracheostomy .
kluger and colleagues   reported a lower incidence of pneumonia when early tracheostomy was performed in brain - injured patients .
nowak and coworkers   identified an increased risk for severe tracheal complications in brain - injured patients who had been intubated for more than 14 days .
the critical issues in developing effective ventilatory management strategies in acute brain - injured patients remain the identification of those patients who are more likely to require long - term ventilatory support and determination of the optimal timing for tracheostomy .
major and coworkers   suggested the utility of daily assessment of objective scores such as glasgow coma scale ( gcs ) and simplified acute physiology score ; scores on these scales of below 7 and greater than 15 , respectively , on day 4 had a high positive predictive value for identifying those head - injured patients who required tracheostomy for prolonged airway protection .
similarly , namen and coworkers   found that a weaning protocol for head - injured patients should always include a neurological assessment using the gcs ; a score greater than 8 on the gcs was most accurate in predicting successful extubation without need for reintubation , and avoiding pneumonia and tracheostomy .
qureshi and coworkers   reported that , in patients with infratentorial lesions , an aggressive policy regarding tracheostomy is justified because of the low rate of successful extubation , and that a that tracheostomy should be performed on day 8 because of the low probability of subsequent extubation or in - hospital death .
selection of this subgroup of patients for tracheostomy is justified because infratentorial lesions located in the cerebellum and brainstem may be associated with damage to the primary neural respiratory centres ( which are involved in coordinating respiration ) , to the lower cranial nerve nuclei ( which are responsible for protective airway reflexes ) , and to reticular activating pathways ( which are responsible for impairment in the level of consciousness and consequently for reduced protective airway reflexes ) .
although early tracheostomy may reduce the length of icu stay and pulmonary morbidity , the first 710 days after acute brain injury coincide with the greatest incidence of intracranial hypertension ; the appropriate timing for tracheostomy in these patients must be considered in view of the risk for severe intracranial hypertension .
stocchetti and coworkers , in a randomized control trial comparing three tracheostomy techniques , included patients ventilated from 4 days but excluded patients with unstable intracranial pressure requiring active treatment .
the patient described in the scenario above appears to meet standard weaning criteria and has stable intracranial pressure but a low gcs score , indicating that he patient has impaired ability to protect his airway .
we therefore believe that the patient should receive tracheostomy to reduce the length of icu stay and the likelihood of pulmonary complications .
david stather and niall d ferguson the management of a brain - injured patient with satisfactory weaning parameters but a decreased level of consciousness is a common critical care scenario .
the role of tracheostomy in this setting , however , has yet to be clearly defined .
tracheostomy has been shown to decrease the work of breathing , but this is not the issue in this scenario .
aspiration of oropharyngeal contents is common in neurologically impaired patients , but tracheostomy may not protect against aspiration .
a retrospective study of traumatic brain - injured patients   found a high incidence of pneumonia in those with prolonged intubation , probably because of a loss of normal upper airway defences caused by the presence of the endotracheal tube .
unfortunately , tracheostomy does not necessarily reduce the incidence of nosocomial pneumonia ; in fact , the presence of a tracheostomy has been associated with a sixfold increased risk for developing ventilator - associated pneumonia .
tracheostomy has been associated with decreased icu and hospital mortality in observational cohort studies of mechanically ventilated patients .
this effect , however , is probably related to a selection bias created by the fact that patients needed to survive their first 1020 days of ventilation in order to receive a tracheostomy . when the same observational data were examined in a matched case 
control design , tracheostomy patients had longer icu and hospital lengths of stay , and a lower icu mortality , but importantly they had no decrease in hospital mortality .
brain dysfunction can contribute to extubation failure in a number of ways , such as by decreasing the patient 's ability to protect their airway and clear secretions .
namen and coworkers   found that a gcs score below 8 was associated with an increased likelihood of extubation failure in neurosurgical patients .
coplin and colleagues , however , found no relationship between extubation failure and gcs score . in that prospective observational cohort study , those investigators found that 39 out of 49 patients with gcs score of 8 or less , and 10 out of 11 patients with a gcs score of 4 or less tolerated extubation .
in addition , they showed that brain - injured patients who had delayed extubation developed more pneumonias , had longer lengths of stay , and incurred more hospital charges than did similar patients who were extubated promptly after meeting standard weaning criteria .
it is possible that tracheostomy could improve the outcome of brain - injured patients in whom upper airway obstruction or problematic secretions could cause extubation failure .
its utility in other patients with simple decreased level of consciousness is much less certain .
for example , evidence - based guidelines for discontinuing ventilatory support do not include brain - injured patients in a list of populations who may derive particular benefit from early tracheostomy .
returning to our scenario , if a plan for ongoing aggressive care has been made after appropriate consideration of prognosis and family discussions , then options from this point would include continuing orotracheal intubation , tracheostomy placement , or primary extubation .
there is currently no clear evidence to suggest that performing a tracheostomy in this setting would improve outcome .
carefully planned prospective studies , both observational and interventional , that examine the need for and optimal timing of tracheostomy in brain - injured patients are needed to better address this common clinical question .
luciana mascia , eleomore corno and pier paok terragni although the need for and optimal timing of tracheostomy for brain - injured patients is a common clinical problem , no large randomized trials have unequivocally clarified whether this intervention improves outcome .
while we await definitive answers , we should select subgroups of brain - injured patients who may benefit from this intervention .
because of his severe neurological impairment , the patient described in the scenario presented above could be a good candidate for trachestomy to protect his airways .
david stather and niall d ferguson the common theme underpinning both the argument presented by mascia and colleagues and our own is the clear lack of rigorous , prospective data regarding the utility and optimal timing of tracheostomy in brain - injured patients . even in the non - neurosurgical critical care population ,
there is insufficient and conflicting evidence regarding whether the timing of tracheostomy alters the duration of mechanical ventilation or extent of airway injury .
this paucity of data should not lead us to make definitive recommendations based on an incomplete understanding of the problem .
instead , we must recognize that further scientifically rigorous results are needed before this is important clinical question can be answered .
 most clinical trials on the topic of extubation have involved patients outside the neurological intensive care unit . as a result , in this area 
 clinicians are left with little evidence on which to base their decision making . although tracheostomies are increasingly common procedures , they are not without complications and costs , and hence a decision to perform them should not be taken lightly . in this issue of critical care 
 two groups debate the merits of tracheostomy before extubation in a patient with neurological impairment . 
 what becomes very clear is the need for more high quality data for this common clinical problem . 
The scenario
Pro: Tracheostomy is ideal for withdrawal of mechanical ventilation in severe neurological impairment
Con: Tracheostomy is not ideal for withdrawal of mechanical ventilation in severe neurological impairment
Utility and timing of tracheostomy in brain injured patients need to be assessed prospectively
Con response: Prospective studies are needed to identify subsets of neurologically impaired patients who might benefit from tracheostomy
Competing interests
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