Objectives

1. To discuss the timing for tracheotomy in patients requiring mechanical ventilation in the ICU.
2. To describe the complications of early vs late tracheotomy.
3. To evaluate the recommendations from the consensus statement on the timing of tracheotomy.
4. To review the available literature comparing surgical tracheotomy (ST) vs percutaneous dilational tracheotomy (PDT).
5. To identify patients who would benefit from an ST vs a PDT.

Abbreviations

PDT = percutaneous dilational tracheotomy; ST = surgical tracheotomy; TLI = translaryngeal endotracheal intubation;

Introduction

Early surgical tracheotomy was once a common practice. This procedure, however, was associated with frequent and numerous complications.^1,2 These problems and a better understanding of the mechanisms of injury from endotracheal tubes resulted in the development of improved translaryngeal tube design and construction.¹ These new products and a fear of the high complication rates associated with tracheotomy led to delays in conversion from translaryngeal intubation to tracheotomy.³

Currently, the timing of converting critically ill, ventilator-dependent patients from a translaryngeal endotracheal tube to a surgical or percutaneous tracheostomy tube remains controversial. Evidence-based data from large, well-executed, randomized, controlled trials are lacking. The multitudes of retrospective series that have been published are hampered by the diversity, complexity, and severity of the various diseases in these critically ill patients as well as physician bias. The decision to perform an early tracheotomy vs continuing translaryngeal endotracheal intubation (TLI) requires accurate knowledge of the following parameters:

1. Factors leading to laryngeal damage with TLI;
2. The complication rates of surgical and percutaneous tracheotomies;
3. The incidence of subglottic and tracheal stenosis with continued TLI vs tracheotomy;
4. Security of the airway with TLI vs tracheotomy; and
5. Demonstrable differences in clinical end points with TLI vs tracheotomy (including rates of nosocomial pneumonias, ventilator-dependent days, total ICU days, length of hospital stay, and cost). 4-9

Consensus Statement

The only consensus statement recommending a specific time frame for conversion to tracheotomy was published in CHEST in 1989.⁴ The authors list the benefits of tracheotomy as follows:

1. Sparing further direct laryngeal injury from the translaryngeal tube;
2. Facilitating nursing care (specifically airway suctioning and mouth care);
3. Increasing patient mobility by providing a more secure tube;
4. Facilitating transfer from the ICU setting;
5. Improving comfort;
6. Permitting speech;
7. Facilitating oral nourishment; and
8. Providing psychologic benefit.

Disadvantages listed in the consensus statement include:

1. Cost of the procedure; and
2. Complications attributed to the tracheotomy.

The recommendations from the consensus group were as follows:

1. For anticipated need of the artificial airway up to 10 days, the translaryngeal route is preferred.
2. For anticipated need of the artificial airway for >21 days, tracheotomy is preferred.
3. When the time anticipated for the maintenance of an artificial airway is not clear, daily assessment is required to determine whether conversion to tracheotomy is indicated.
4. The decision to convert to tracheotomy should be made as early as possible in the course of management to minimize the duration of translaryngeal intubation.

The consensus group prefaced these recommendations with the statement, "there is no specific time at which a translaryngeal tube must be removed and a tracheotomy performed. The decision to convert to a tracheostomy tube must be based on individual patient factors, including anticipated degrees of improvement or deterioration over time."⁴

Laryngeal Injury

Two mechanisms are thought to contribute to laryngeal injury from to an endotracheal tube. One is the abrasion of the mucosa of the larynx from the to-and-fro motion of the tube. Extension and flexion of the neck has been shown to move an indwelling endotracheal tube a mean distance of 3.8 cm. The second mechanism is direct pressure applied posteriorly on the laryngeal cartilages by the endotracheal tube resulting in areas of necrosis.¹⁰ This is the most important mechanism and can cause damage to both the arytenoids and the cricoid cartilage.

In 1984, Whited published data supporting early tracheotomy to avoid laryngeal damage from prolonged TLI.² He reported increasing frequency and severity of posterior commissure stenosis with increasing lengths of intubation. Colice and colleagues¹¹ prospectively studied 82 patients intubated for varying durations and evaluated tracheal damage. They also found that the severity of laryngeal damage on initial examination performed after extubation or change to a tracheostomy tube correlated with the length of time the patient was intubated transtracheally. The authors, however, found little correlation between the severity of damage at the initial laryngoscopic evaluation and long-term clinical consequences. Unlike Whited, none of their patients developed progressive laryngeal scarring with stenosis. Additionally, Colice¹² found that laryngeal injuries healed quickly, and healing was dependent on neither the severity of the injury nor a TLI duration of >10 days. Stauffer and colleagues³ also randomly assigned patients to either early tracheotomy or continued TLI for up to 21 days, and found no relationship between duration of endotracheal intubation and extent of laryngeal damage seen at autopsy. Two other randomized trials comparing late vs early tracheotomy included laryngoscopic examinations and found no significant differences in laryngeal damage with prolonged TLI.^13,14 In one of the studies, repeat laryngoscopic examinations 3 to 5 months after initial extubation revealed complete resolution of the laryngeal damage.¹⁴ Of note, all these studies considered 7 to 21 days as the duration of extended TLI. There are no series with prolonged TLI of >21 days.

The frequency and extent of laryngeal damage following TLI varied with differing studies and was not predictable with longer durations of TLI. Furthermore, the larynx heals quickly after injury, usually with few sequelae. Laryngoscopic examination findings at the time of extubation are a poor predictor of clinically relevant damage. Significant long-term morbidity with TLI of up to 14 to 17 days has been reported to be minimal.

Complications of Tracheotomy

In a prospective study, Stauffer et al³ randomly assigned 150 patients who had received translaryngeal intubation for >48 h to undergo immediate tracheotomy or to continue prolonged TLI. The authors found that 62% of those patients in the continued-TLI arm of the study suffered adverse consequences. These adverse events included excessive cuff pressure, self-extubation, and air leak. Sixty-six percent of the patients who underwent early tracheotomy also had complications, including stomal infections, stomal hemorrhage, and excessive cuff pressures. One patient experienced massive hemorrhage at the time of the tracheostomy tube placement, and another had hemoptysis at 28 days because of erosion from the cuff site into the inferior thyroid artery. Two patients experienced cardiorespiratory arrests that directly related to the placement of the tracheostomy tube. The authors stated that although the frequency of complications was similar in these two groups, those complications associated with tracheotomy were of greater severity. They also concluded that TLI was preferred for durations of ≤3 weeks.³ Although Stauffer et al³ did include early complications, those occurring perioperatively were not listed separately.

Stock et al¹⁵ reported that the mortality associated with tracheotomy was <1%, with a <2% rate of major morbidity and <6% rate of minor morbidity without long-term sequelae. In a randomized trial comparing early (3 to 7 days) and late (8 to 21 days) tracheotomy, the incidence of tracheotomy morbidity "defined as bleeding, infection, pneumothorax, stenosis, or fistula formation" was a low 4% in each group.¹

Tracheal Stenosis

Tracheal stenosis can be a complication of either TLI or tracheotomy. In TLI, stenosis usually occurs at the site of the cuff or at the tip of the endotracheal tube. With tracheotomy, stenosis usually occurs at the site of the tracheotomy after decannulation. Two important issues relating to timing of tracheotomy include the relative frequencies of tracheal stenosis with tracheotomy vs continued TLI and the frequency and severity of stenosis with early vs late tracheotomy.

Tracheal stenosis is often stated to be of greater frequency and concern with tracheotomy than with TLI.¹⁶ The incidence of stenosis ranges between 0 and 16% for different series depending in part on the definition of stenosis.⁷ In their study, Stauffer et al³ found a 19% incidence in tracheal narrowing of ≥10% by tomography in those patients with prolonged TLI vs a 65% incidence of stenosis in the group with early tracheotomy. The severity of stenosis was stated to be similar in both groups. Overall clinical significance of the narrowing was not reported. Dunham and LaMonica¹³ reported no significant difference in the incidence of major laryngotracheal pathology in a study comparing early (3 to 4 days) and late (14 days) tracheotomy. The incidence of tracheal damage was 17.6% and 12.5%, respectively. They did not separate the complications into laryngeal vs tracheal damage. Dunham and LaMonica¹³ also found no correlation between stenosis and the length of time intubated, nor a difference in the severity of major laryngotracheal pathology with TLI vs tracheotomy. Rodriguez et al¹ included tracheal stenosis with tracheotomy morbidity outcome and found no difference with respect to timing of tracheotomy. In most series, the frequency of tracheal stenosis with tracheotomy is low, especially when the procedure is performed percutaneously. The timing of the tracheotomy does not appear to affect the incidence of tracheal stenosis.

Secure Airway

Accidental extubation is not a benign process and carries more serious complications for patients receiving TLI than for those with a tracheostomy tube.¹⁶ In the study by Stauffer et al³, accidental extubation occurred in 13% of all patients. When patients were reintubated by house staff, 33% of intubations took >2 min, with 20% requiring four or more attempts. One patient underwent cardiac arrest during prolonged attempts. Coppolo and May¹⁷ cite an 11% overall incidence of unwanted extubation with TLI; 11% of patients needed reintubation and the rate of complications attributed to the extubation was 31%.

Other Clinical End Points

Prospective, randomized studies of early vs late tracheotomy suggest no differences in incidence of nosocomial infections. El-Naggar et al¹⁸ found increased bacterial colonization in their early-tracheotomy group. The clinical significance of this colonization, however, was not known. Dunham et al¹³ found similar incidences of infection (tracheitis, pneumonia, lung abscess, and peristomal infection) between early- and late-tracheotomy groups. Brook et al¹⁹ found no differences in nosocomial pneumonias in their study. Rodriguez et al¹ found a statistically significant reduction in rates of pneumonias in those patients who received tracheostomies within 48 h. Rates of pneumonias were similar among patients in whom tracheotomy was performed at 3 to 7 days vs after 8 days.

Armstrong and colleagues²⁰ retrospectively reviewed their experiences with early and late tracheotomy. They found similar injury severity scores and mortality rates, but demonstrated a significantly shorter length of ICU stay (mean, 15 vs 29 days) and hospital stay (mean, 33 vs 68 days), and significantly lower hospital charges (mean, $36,609 vs $73,714) for patients who received early tracheotomy. Brook and colleagues¹⁹ prospectively studied 90 patients with tracheostomies, defining 10 days as the cutoff for late vs early tracheotomy. They also found shorter ICU stays and total hospital length of stays and significantly decreased hospital costs with early tracheotomy. Rodriguez et al¹ randomly assigned 106 patients to early (<7 days) or late (>7 days) tracheotomy. They found decreases in time requiring mechanical ventilation, ICU days, and total hospital days with early tracheotomy.

Surgical Tracheotomy vs Percutaneous Dilational Tracheotomy

With the increase in complexity and survival of critically ill patients, the number of patients requiring tracheotomy for prolonged mechanical ventilation has increased. Subsequently, a demand for an alternative procedure to the standard surgical tracheotomy (ST) has emerged. Presently, percutaneous dilational tracheotomy (PDT) has become the best alternative to ST. Its theoretical advantages over ST include eliminating the need for general anesthesia and operating room use, easier scheduling, and significantly reduced costs. In this section of the manuscript, we will review the complications of PDT and analyze any available literature comparing the two procedures.

Complications of PDT

As experience with PDT increases, certain complications not typically seen with ST have been encountered. These include barotraumas (pneumothorax, mediastinal emphysema, and subcutaneous emphysema), tracheoesophageal fistula, and paratracheal insertion.^21-23

Complications with PDT occur more frequently during the learning period and are seen predominantly for the first 20 procedures a physician performs. Experimental evidence strongly supports the concept that there is clearly a learning curve associated with PDT.^24,25 Although this is rarely done, the initial experience with PDT is best obtained under controlled circumstances, preferably in the operating room.^26,28 During the learning phase, video-assisted bronchoscopy is strongly recommended.^29,30 This virtually eliminates the 1% complication rate of paraesophageal insertion.^31,32 Some investigators have not reported learning curve difficulties.³³ When Bowen and colleagues³³ at the University of Virginia Medical Center described their initial experience with PDT in their comparative study of ST vs PDT, there was no difference in rates of complications seen with the initial 30 procedures as compared with the subsequent 44 PDTs. There were also no differences found between surgical specialists or nonsurgeons performing PDTs.

Although most complications occur during acquisition of early experience with PDT, certain life-threatening complications, such as tube dislodgement or inability to complete the procedure, may occur even after extensive experience.²⁵ Airway loss is a serious complication of PDT and occurs most commonly with endotracheal tube repositioning either before or during the procedure. Although this complication occurs infrequently, it has been reported as the cause of death in some cases.

Features unique to PDT that increase the risk of delayed airway loss include a narrow dilated tract, the tight fit of the pretracheal conduit around the cannula, and the lack of formal stoma creation. Also, the smaller PDT stoma does not always improve with maturation. Without a formal stoma and with only a narrow tract between the airway and the skin, tracheal tube displacement represents a potentially catastrophic complication of PDT.^25,34-37 Tracheostomy tube change should thus be avoided for the first 7 days.^21,22 An appropriately sized tracheostomy tube and cannula should be placed initially to avoid the need for early tracheostomy tube change.²⁸ Owing to the size of the pretracheal conduit and the use of a tracheal flap that anchors the trachea to the skin of the neck, this is less of a problem with ST. For these reasons, ST may be preferred in patients with a difficult airway in whom loss of the airway could result in a fatal outcome.²⁸

Local hemorrhage and wound infections can occur and usually respond well to local treatment in most of the patients undergoing PDT. The vast majority of studies reporting complications after PDT include few cases in which infection or bleeding has had a significant impact in the care of the patient. There is also no evidence for the need of a change of therapy, prolonged admission, or surgical intervention to handle PDT-related complications.

Major late complications with tracheotomy include tracheal stenosis, subglottic stenosis, tracheomalacia, skin fistulas, tracheoinnominate artery fistulas, and cosmetically unsatisfactory scars. The incidences of these complications with PDT are confounded by the high short-term mortality in the critically ill population in whom this procedure is usually performed. There is currently no study that has prospectively reviewed the complication rates of PDT in long-term survivors.³⁸ Tracheal stenosis has been reported in 5 to 10% of patients undergoing PDT.^25,39,40 These include only isolated case reports of "significant" (>20% or symptomatic) stenosis. Confounding factors in assessing these late complications include airway injury caused by prior TLI, duration of the tracheotomy tube dependence, and the location of the stenosis. Stenosis is frequently reported in the area of the tracheostomy tube cuff, an area that on a theoretical basis should not be related to the procedure.

Comparative Studies

Since the initial description, PDT has gained widespread acceptance as a method for creating an elective surgical airway in patients requiring long-term mechanical ventilation.⁴¹ However, the benefits and risks of this technique over conventional ST have been derived mainly from observational studies, with only a limited number of comparative studies. This section summarizes the available comparative data.

Time Required for the Procedure

Most studies quote a 20-min advantage in favor of PDT over ST.^27,37,41-43 Much of the difference in time, however, relates to decreased patient preparation time and set-up time for PDT vs ST. This time difference likely has no meaningful clinical significance but does emphasize the relative technical simplicity of PDT when compared with conventional ST. In similar clinical settings, both procedures can be performed quickly with little clinically significant differences in procedure time.⁴⁴

Mortality

A mortality analysis comparison is difficult to perform as a result of the low mortality of the procedure itself and the high overall mortality of the targeted patient population. In most of the studies, the mortality directly related to the procedure is very low, with no statistically significant difference between ST and PDT⁴⁴ (Table 1).

Table 1. Prospective Studies Comparing ST and PDT

Time Delay Once the Decision for Tracheotomy Is Made Before the Procedure Is Performed

Although this important clinical aspect has not been studied extensively, Friedman and colleagues²⁷ found that the time interval from randomization to tracheotomy was significantly shorter in the PDT group (28.5 h) than the ST group (100.4 h). With no need to schedule operating room time, PDT can be performed sooner once the decision for tracheotomy is made. The clinical significance of this time difference needs further evaluation.

Cosmetic Results

With minimal tissue disruption, the cosmetic results are thought to be better with PDT than with ST.⁴⁵ In most of the patients, the tracheotomy scar from PDT is <2 cm in length. The cosmetic results also depend on how long the tracheotomy tube is in place. Patients cannulated for >4 weeks are at an increased risk for a retracted, sunken scar.⁴⁰

Bleeding and Infections

In general, the rates of major infection or bleeding leading to serious complications or death are very low for both PDT and ST (Table 1). Some studies report fewer hemorrhages and wound infections with PDT.^{26,27,36,37,46} Others, however, have demonstrated no difference.^34,43,44,47

Cost

Although intuitively the PDT is less expensive than ST, there are no formal studies analyzing cost. The cost differential favors PDT if the comparison is made between ST performed in the operating room and PDT performed at bedside. With ST, open tracheotomy expenses are dominated by room and anesthesia-related costs.⁴⁸ In several observational studies, the reduction in hospital charges per procedure associated with performing PDT at the patient's bedside, compared with performing ST in the operating room, ranges from approximately $1,200 to $3,300.^42,49-51 In contrast, when both procedures are performed in the operating room, the reduction in hospital charges is minimal, approximately $300 in favor of PDT.^42,52 In hospitals where a selected team performs ST in the ICU, the cost of ST is actually lower than PDT with bronchoscopic guidance.³⁴

Meta-analysis of Clinical Trials

Currently all available randomized clinical trials comparing PDT to ST are small and carry a risk for false negative or false positive results. These studies are unable to consistently define one procedure as superior with regards to either morbidity or mortality.⁴⁸ A large randomized, prospective trial is needed to definitively elucidate any differences. Meta-analysis classically fulfills its primary role by aggregating data from conflicting or underpowered studies in an attempt to establish statistical evidence of the value of an intervention.⁵³ Two meta-analyses published recently have shown that the results of both techniques are similar and conclude that either procedure is a reasonable choice with respect to risks and complications.^23,41 Both of these meta-analyses include varied patient populations and design methods, making the results somewhat difficult to interpret.^38,54 Freeman and colleagues⁴¹ conclude that PDT is performed more quickly, has a lower operative bleeding rate, and is associated with fewer postoperative complications than ST. The differences in these end points, however, are not consistent among all trials. Another advantage with bedside PDT described from meta-analysis is the avoidance of a potentially hazardous transport of the patient outside the ICU. The meta-analysis by Dulguerov and colleagues²³ confirms the results of the studies described above, but continues to fail in clearly demonstrating a difference between ST and PDT. This meta-analysis reports a decrease in procedure time with PDT. The authors also validated the safety of PDT when performed at the bedside.

Conclusions

When significant clinical end points are considered, PDT is a cost-effective and safe alternative to ST in critically ill patients in the ICU when the procedure is performed by skilled and experienced practitioners.^42,53 There is insufficient data to establish clear superiority of PDT over ST. Important advantages of PDT may include eliminating the need for operating room facilities and personnel because the procedure is performed at the bedside, and significantly decreasing the time interval between the decision to perform tracheotomy and the actual performance of the procedure.^28,42,44

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