Trauma is currently one of the most important causes of morbidity and mortality in the age group between 15 to 35 years 1. About 500,000 people are hospitalized yearly in the United States as a result of motor vehicular accident-related injuries 1. In addition, motor vehicle-related deaths and injuries cost the United States more than $150 billion each year 1. According to World Health Organization statistics for the year 2000, over 50% of global mortality due to road traffic accidents occurs among young adults and the mortality rates per 100,000 is in the range of 18.7 to 34.1 in the Eastern Mediterranean region and between 11.2 and 16.1 in Europe 2. Many trauma patients require intubation and mechanical ventilation for several reasons, including relief of upper airway obstruction secondary to severe facial or laryngeal trauma, airway access in patients with cervical spine injury, management of retained airway secretions, maintenance of patent airway and airway access for prolonged mechanical ventilation 3. The percentage of trauma patients who require tracheostomy varies considerably and ranges from 14% to 48% 456.

Traditionally, tracheostomy has been provided for trauma patients who required endotracheal intubation for a prolonged period of time. In 1989, the American College of Chest Physicians' Consensus Conference on Artificial Airways in Patients Receiving Mechanical Ventilation recommended that tracheostomy should be considered in patients anticipated to require endotracheal intubation for more than 21 days 7. It also recommended, however, that if tracheostomy is indicated, it should be done early to minimize the duration of translaryngeal intubation and lower the incidence of associated complications. Recently, there has been an increasing trend towards converting endotracheal intubation to tracheostomy at an earlier stage as more evidence supports the benefits of early tracheostomy 58910. Whited 11 conducted a prospective study involving 200 medical and surgical intensive care unit (ICU) patients to assess the effect of duration of intubation on airway pathology. Before starting the study, they divided patients into three groups based on arbitrary thresholds of duration of endotracheal intubation: 2 to 5 days, 6 to 10 days and more than 10 days. The authors concluded that the risk of serious and irreversible airway complications increased after the 10^th day of translaryngeal intubation. In those who were intubated for ≤ 10 days, the incidence of chronic airway stenosis was 5% compared to 12% in those who were intubated for more than 10 days. The controversy regarding the ideal timing of tracheotomy in trauma patients continues, however, because of the absence of large-scale, well-designed prospective randomized trials. The purpose of this article is to review the available data related to the advantages and disadvantages of early tracheostomy in critically ill trauma patients. The review is constructed to evaluate the effects of timing of tracheostomy on the following endpoints: patho-physiological endpoints, including laryngeal injury, respiratory mechanics and dead space ventilation; and clinical endpoints, including duration of mechanical ventilation, patient comfort, ICU length of stay and the incidence of ventilator-associated pneumonia. In addition, we will examine the indications of tracheostomy in trauma patients. These indications include relief of upper airway obstruction, airway access in patients with cervical spine injury, management of retained airway secretions, maintenance of patent airway, and airway access for prolonged mechanical ventilation. Benefits of early over late tracheostomy and predictors of which trauma patients are likely to require tracheostomy will also be reviewed.

Translaryngeal intubation for prolonged periods of time is associated with several complications 412, which are summarized in Table 1. On the other hand, conversion of translaryngeal intubation into tracheostomy is associated with several advantages 4 listed in Tables 2 and 3. Some of the evidence on the advantages of tracheostomy is extrapolated from non-trauma patients because of the lack of trauma-specific literature in certain areas.

In critically ill trauma patients, tracheostomy may be indicated for several reasons. Table 4 summarizes studies that have examined the indications of tracheostomy in trauma patients.

Cervical injuries requiring stabilization may represent a significant challenge in airway management. If the patient needs early halo immobilization, easy access to the airway is prevented as a result of inability to extend the neck. Sims and Berger 44 conducted a retrospective chart review of 105 trauma patients with cervical spine injury who required halo fixation. The incidence of urgent intubation was 13% and a total of 17 tracheostomies were done, of which 8 were performed without a trial of extubation and the remainder were done after an emergent intubation following an extubation trial. Six patients died as a result of emergent intubation whereas none of the patients who underwent elective tracheostomy died. The authors recommended that early tracheostomy should be considered in patients with cervical spine injury requiring halo fixation, especially if they have a high injury severity score, have cardiac disease, are older than 60 years, or have a past history of difficult intubation, and are anticipated to require an artificial airway for more than one week.

An important concern in quadriplegic patients who require tracheostomy is the inability to extend the neck, which has been considered to be a relative contraindication for percutaneous tracheostomy 45, although percutaneous tracheostomy has been reported in this setting. Mayberry et al. 45 conducted a prospective study of 88 trauma patients receiving percutaneous tracheostomy. The procedure was performed without neck extension in the group of patients with the non-cleared cervical spine; the success rate was 96% for the non-cleared group compared to 100% in the cleared group and no patient had spinal cord injury caused by the procedure. The authors concluded that percutaneous tracheostomy is a safe procedure in trauma patients without cervical spine clearance. Another related issue is the delay of tracheostomy in patients who have undergone anterior surgical fixation of the spine until the surgical wound is healed 46. Percutaneous tracheostomy minimizes injury to the adjacent neck structures and thus also the risk of stomal infection 46 and should be considered in patients who have undergone anterior fixation of the cervical spine and require prolonged ventilatory support 4748.

Trauma patients can lose the ability to clear retained secretions and maintain patent airway for several reasons. Head injury may result in airway compromise as a result of decreased mental status or absent airway protective reflexes (cough and gag reflexes). Such patients usually do not need mechanical ventilatory support and are intubated mainly for airway protection 49. If tracheostomy is performed in these patients, they can be librated from mechanical ventilation rapidly and be transferred out of the ICU in a shorter time 589102049.

Koh et al. 6 conducted a retrospective study on 49 patients, 20 of which were victims of trauma, who required admission to the neurosurgical ICU. In this study, the reintubation rate was 22% despite meeting weaning criteria. Among the predictors of failed extubation were low Glasgow Coma Scale (GCS) and excessive tracheal secretions. The majority of patients who required reintubation were librated from mechanical ventilation within 48 hours of tracheostomy. This indicated that intubation was only required for the purpose of airway protection and, once the airway was secured via tracheostomy, patients were librated rapidly from ventilatory support. The authors concluded that if the patient is thought to have a poor long-term prognosis in terms of airway protection, early tracheostomy should be done to help in early transfer of the patients out of the ICU.

Boyd and Benzel 50 conducted a retrospective analysis of 116 tracheostomized neurosurgical patients, of whom 43% had head injury and 7% had cervical spine injury. The overall rate of complications related to tracheostomy was 6% and no deaths were attributable to the procedure. Thirty-two patients had evidence of pneumonia prior to tracheostomy, whereas eighteen patients developed pneumonia after tracheostomy. The low rate of complications related to tracheostomy in this study may be due to the short pre-tracheostomy period of endotracheal intubation (average of 5.8 days). The authors concluded that early tracheostomy is a beneficial and safe procedure in critically ill neurosurgical patients and that early tracheostomy can prevent many of the complications associated with prolonged translaryngeal intubation.

Critically ill trauma patients may require prolonged mechanical ventilatory support for a variety of reasons: severe chest trauma resulting in lung contusion, multiple rib fractures, flail chest or hemothorax can be associated with prolonged mechanical ventilation. Trauma patients are at risk of nosocomial pneumonia, which is associated with prolonged mechanical ventilation. The incidence of nosocomial pneumonia in trauma patients ranges from 20% to 40% 51. Acute respiratory distress syndrome (ARDS) is another reason for prolonged mechanical ventilation in trauma patients. The incidence of ARDS in trauma patients is variable. In a study by Johnston et al. 52, 12% of trauma patients developed ARDS. In addition, trauma patients who sustain spinal cord injury usually need prolonged ventilatory support if this injury resulted in diaphragmatic paralysis.

Timing of tracheostomy has been a subject of debate. Several studies examined the effect of early tracheostomy on the duration of mechanical ventilation, ICU and hospital length of stay, compared to that of late tracheostomy.

There are some limitations in these studies, including the retrospective design of some studies, the use of quasi randomization methods in some of the randomized trials, the variable definition of early versus late tracheostomy, and the absence of blinding. Keeping these limitations in mind, the studies that compare early versus late tracheostomy are reviewed below. Table 5 summarizes the findings of these studies.

Dunham and La Monica 3 prospectively randomized 74 trauma patients to early tracheostomy (3 to 4 days post intubation, n = 34) and late tracheostomy (> 4 days, n = 40). They did not find any significant difference between the two groups regarding laryngotracheal pathology or respiratory infection. However, the number included in this study was too small to draw any meaningful conclusion, and only 65% of patients underwent laryngoscopic examination to detect airway injury.

Rodriquez et al. 5 studied 106 mechanically ventilated trauma patients in a prospective randomized controlled study. They randomized 51 patients to early tracheostomy (within 7 days of intubation) and 55 patients to late tracheostomy (> 7 days). They were able to demonstrate a significant decrease in the duration of mechanical ventilation, and ICU and hospital length of stay in patients randomized to early tracheostomy. They found that the incidence of pneumonia was significantly reduced only in those who had tracheostomy done earlier than three days post-intubation. This study did not describe the weaning protocol used. In addition, patients who were assigned to the late tracheostomy group who had been weaned successfully before undergoing the procedure were not included in data analysis, which may result in a bias as this favors a shorter duration of care to the early tracheostomy group.

Lesnik and coworkers 8 retrospectively studied 101 patients with blunt multiple trauma of which 32 were tracheostomized within 4 days of intubation. Early tracheostomy resulted in reduction of mechanical ventilation duration as well as in the incidence of nosocomial pneumonia. The length of ICU stay and the duration of hospitalization were not reported. The limitations of this study include that the technique of tracheostomy and the selection criteria for the procedure were not described, in addition to its retrospective design. Armstrong and colleagues 9 performed a retrospective chart review of 157 blunt trauma patients who were divided into an early tracheostomy group (≤ 6 days of intubation, n = 62) and late tracheostomy group (> 6 days, n = 95). They found that early tracheostomy was associated with a decrease in the ICU and hospital length of stay.

D'Amelio et al. 10 studied 43 trauma patients retrospectively, 31 of whom underwent tracheostomy. Patients who had tracheostomy done within the first 7 days of intubation had lower mechanical ventilation duration as well as ICU and hospital length of stay.

Arabi and coworkers 20 examined the impact of early versus late tracheostomy on the outcome of trauma patients. They studied 653 trauma patients, of whom 136 (21%) underwent tracheostomy: 29 patients had early tracheostomy (≤ 7 days of mechanical ventilation) and the remainder had late tracheostomy (> 7 days). They found that the duration of mechanical ventilation and ICU length of stay were significantly shorter in the early tracheostomy group. Mortality rates were similar in both groups.

Bouderka et al. 21 prospectively studied 62 trauma patients with isolated head injury. They randomized them in two groups: an early tracheostomy group (5th to 6th day, n = 31); and a late tracheostomy group (after 6th day). The investigators found that the mechanical ventilation duration was shorter in the early tracheostomy group. There was no difference in the frequency of pneumonia or mortality between the two groups.

Surgerman et al. 53 conducted a prospective, randomized multicenter study of 157 patients. All patients were victims of trauma (head and non-head injury), apart from 18 who were non-trauma patients. The 157 eligible patients were randomized on days 3 to 5 to receive tracheostomy or to continue with translaryngeal intubation. Patients who remained intubated were randomized again on days 10 to 14. They found that ICU length of stay and the frequency of pneumonia did not differ between the two groups. The study had several limitations, however: of five participating centers, only one completed the study. In addition, of 157 eligible patients, only 112 completed the study because of physicians' bias and incomplete information.

Maziak et al. 22 performed a systematic review concerning the timing of tracheostomy. Their meta-analysis consisted of five studies, three of which were done on trauma patients 358. The authors concluded that there was insufficient evidence to support that early tracheostomy could result in shorter mechanical ventilation or lower airway injury in critically ill patients. There are many limitations to this systematic review, however, including the mixed population of patients (trauma and non-trauma) and two studies being retrospective chart reviews, in addition to the significant limitations of the randomized controlled trials.

A more recent meta-analysis that included five randomized trials with mixed patient populations (trauma, medical, surgical, and burn) concluded that early tracheostomy reduced the duration of mechanical ventilation and length of ICU stay significantly but did not significantly change mortality or risk of pneumonia 54.

Performing tracheostomy during early stages of severe brain damage may raise concerns about the effect of the procedure on intracranial pressure. Stocchetti et al. 55 studied prospectively the effect of early tracheostomy on intracranial pressure (ICP), cerebral perfusion pressure (CPP), and jugular oxygen saturation on 20 neurosurgical patients with a GCS less than 8. All patients were selected with an ICP of < 20 mmHg during the 24 hours preceding inclusion in the study. The interval between the initial injury and tracheostomy ranged from 2 to 12 days with a mean of 5 ± 2.46 days. The authors found that tracheostomy did not lead to significant changes in ICP or CPP in the majority of cases. Only in some cases, brief episodes of intracranial hypertension occurred with an increase in the ICP above 20 mmHg. They concluded that early tracheostomy (≤ 12 days) is well tolerated in the majority of cases and did not lead to a persistent rise in ICP. They recommended proper patient selection, however, with avoidance of those with unstable ICP, in addition to close monitoring of ICP during tracheostomy.

What is the optimum time for performing tracheostomy in critically ill trauma patients? The best answer to this question requires one to weigh the benefits and risks of tracheostomy. The complications associated with prolonged translaryngeal intubation and the advantages of tracheostomy have been discussed earlier in this review. One must stress that the decision should be individualized. In our center, we perform early tracheostomy (< 7 days) on patients with severe brain injury (GCS ≤ 8), those expected to be ventilated for more than 10 days, patients who are judged to be unable to protect their airways and in the absence of spontaneous cough. We tend to delay tracheostomy to give an extubation trial for patients who have a GCS higher than 8, those who are showing rapid recovery and those with spontaneous cough. We should emphasize that selection criteria for early versus late tracheostomy have not been validated in randomized controlled trials, although there are certain variables that can help the intensivist in predicting who is likely to need prolonged mechanical ventilation and possibly tracheostomy.

The decision to perform early tracheostomy can be guided if the patient is predicted to require prolonged mechanical ventilation. Table 6 summarizes the studies examining predictors for prolonged mechanical ventilation in trauma patients.

Ross and colleagues 4 examined the ability of injury severity measures, oxygenation, and mental status to predict the need for prolonged ventilatory support in trauma patients. A total of 212 trauma patients were studied. They found that age > 40 years, GCS ≤ 7 and alveolar-arterial oxygen gradient (A-a O2) ≥ 100 to 150 were predictors of prolonged mechanical ventilatory support.

Similarly, Koh and coworkers 6 found that neurosurgical patients with poor GCS and nosocomial pneumonia were at higher risk of extubation failure. Elective tracheostomy in this high-risk group resulted in significantly lower ICU length of stay and shorter duration of mechanical ventilation.

Gurkin et al. 49 examined the factors that can predict tracheostomy in patients with traumatic brain injury. All traumatic brain injury patients who required intubation and survived longer than 7 days were included; 246 patients with head injury were identified, of whom 35 required tracheostomy. They found that a GCS ≤ 8 on presentation and Injury Severity Score ≥ 25 are highly predictive of tracheostomy.

Velmahos and coworkers 56 reviewed 125 patients who required mechanical ventilation for > 48 hours. In this study, prolonged mechanical ventilation was defined as the need for mechanical ventilatory support for > 7 days. The use of a Swan Ganz catheter, injury severity score, PaO2/FiO2 ratio at 48 hours, and positive fluid balance at 48 hours were most predictive of prolonged mechanical ventilation.

Kollef et al. 57 prospectively studied 521 patients requiring mechanical ventilation for more than 12 hours. The patient population included both trauma and non-trauma patients. They found that nosocomial pneumonia, aerosol treatment, witnessed aspiration and reintubation were independently associated with patients having prolonged ventilatory support and tracheostomy.

Major and coworkers 58 conducted a retrospective chart review study of patients with blunt head trauma. Patients were divided into two groups, those who were extubated and those who required tracheostomy. The author found that the GCS on hospital day 3 and simplified acute physiology score were significantly different in the two groups. They concluded that using these two scores may be useful in predicting the need for prolonged airway protection in patients with blunt head injury.

Lanza et al. 59 retrospectively reviewed head injury patients to examine the predictive value of the GCS for tracheostomy in these patients. Of 47 patients divided according to their GCS rating, 34 had a GCS ≤ 7 and 13 had GCS > 7. They found that the likelihood of tracheostomy is significantly greater in patients with GCS ≤ 7. They recommended performing early tracheostomy in those patients to optimize resource utilization. Further studies are required to identify clearly the factors that can predict the need for prolonged endotracheal intubation and mechanical ventilatory support in trauma patients. By adopting a standardized method for selecting patients who will require early tracheostomy, prolonged ICU and hospital stay will be avoided and this will be certainly associated with better resource utilization.

The timing of tracheostomy in trauma patients is still a subject of debate and often influenced by practice preferences. However, numerous retrospective studies and a few randomized controlled studies have demonstrated the benefits of early tracheostomy in trauma patients in terms of ICU and hospital length of stay and mechanical ventilation duration. Large prospective randomized studies are required to define the proper timing of tracheostomy. In addition, predictors of prolonged ventilatory support in trauma need to be validated in large studies. Such predictors are likely to help in selecting patients who will benefit from early tracheostomy.

Nevertheless, the existing data suggest that tracheostomy should be strongly considered if a trauma patient needs more than 7 to 10 days of endotracheal intubation. This general conclusion should be modified on an individual basis, however, taking into account the anticipated duration of mechanical ventilation and the ability to protect the airways.

ARDS = acute respiratory distress syndrome; CPP = cerebral perfusion pressure; GCS = Glasgow Coma Scale; ICU = intensive care unit; ICP = intracranial pressure; PaO2 = partial pressure of oxygen.

The author(s) declare that they have no competing interests.