Optimally fitted tracheal tubes decrease the probability of postextubation adverse events in children undergoing general anesthesia

The effect of saline versus air for cuff inflation on the incidence of high intra-cuff pressure in paediatric MicroCuff® tracheal tubes: a randomised controlled trial

The use of cuffed tracheal tubes in paediatric anaesthesia is now common. The use of nitrous oxide in anaesthesia risks excessive tracheal tube cuff pressures, as nitrous oxide can diffuse into the cuff during the course of surgery. The aim of this single-centre, prospective, randomised controlled trial was to compare the effect of saline versus air for the inflation of tracheal tube cuffs on the incidence of excessive intra-operative cuff pressure in children undergoing balanced anaesthesia with nitrous oxide. Children (age ≤ 16 y) were randomly allocated to receive either saline (saline group) or air (air group) to inflate the cuff of their tracheal tube. The pressure in the tracheal tube cuff was measured during surgery and brought down to the initial inflation level if it breached a safe limit (25 cmH₂ O). Post-extubation adverse respiratory events were noted. Data from 48 patients (24 in each group), aged 4 months to 16 y, were analysed. The requirement for reduction in intra-cuff pressure occurred in 1/24 patients in the saline group, compared with 16/24 patients in the air group (p < 0.001). The incidence of extubation-related adverse events was similar in the saline and air groups (15/24 vs. 13/24, respectively; p = 0.770). The use of saline to inflate the cuff of paediatric cuffed tubes reduces the incidence of high intra-cuff pressures during anaesthesia. This may provide a pragmatic extra safety barrier to help reduce the incidence of excessive tracheal cuff pressure when nitrous oxide is used during paediatric anaesthesia.

Correlation between correctly sized uncuffed endotracheal tube and ultrasonographically determined subglottic diameter in paediatric population

Background and Aims:

Conventional age-based formulae often fail to predict correct size of endotracheal tube (ETT). In this study, we evaluated usefulness of ultrasound in determining appropriate tube size and derived a formula which enables us to predict correct tube size.

Methods:

A total of 41 American Society of Anesthesiologists' physical status 1 and 2 children in the age group of 2–6 years, undergoing elective surgery under general anaesthesia with uncuffed ETT were included in the study. Ultrasonography (US) was used to measure the subglottic diameter after induction of anaesthesia. The trachea was intubated with an ETT that allowed an audible leak between 15–30 mmHg. Pearson's correlation was used to assess the correlation between US measured subglottic diameter (US-SD) with diameter of ETT used. Linear regression was used to derive a formula for predicting ETT size.

Results:

We found that US-SD and patient's age correlated well with actual ETT OD (r: 0.83 and 0.84, respectively). Age-based formula, ETT ID = (Age/3) +3.5 [r: 0.81] had better correlation with actual ETT OD than conventional age-based Cole's formula, i.e., ETT ID = Age/4 + 4 [r: 0.77]. Our results enabled us to derive a formula for selecting uncuffed ETT based on US-SD.

Conclusion:

Our study concludes that although US-SD correlates with actual tracheal tube used and may be useful in choosing appropriate size ETT, there was no difference in number of correct predictions of ETT size by US measurement, universal formula, and locally derived formula.

Endotracheal cuff pressures in the PICU: Incidence of underinflation and overinflation

BACKGROUND

While uncuffed endotracheal tubes have been traditionally used in the pediatric intensive care unit (PICU) population, evidence suggests cuffed endotracheal tubes (ETTs) are also safe to use within this population. Nevertheless, risks related to the use of cuffed ETTs increase when guidelines for safe and appropriate use are not followed. The primary goal of this study was to measure the cuff pressure (CP) using a cuff pressure manometer in a group of intubated pediatric subjects and determine the rate of cuff underinflation (<20 cm H₂0) or overinflation (>30 cm H₂0). The secondary aim was to determine whether CP was associated to gender, age, ETT size, and PICU length of stay prior to CP measurement.

METHODS

This was a prospective observational study conducted in an urban PICU. Pediatric subjects intubated with cuffed ETTs from 1 April 2017 to 1 May 2017 were included in the study. ETT CPs were measured daily to determine degree of inflation and compared according to gender, age, ETT size, and number of days intubated prior to CP measurement. Descriptive data are expressed as means and standard deviations. A two-sample t test was used to compare groups according to age, gender, and number of days present. And significance was considered with a P < 0.05. Pearson chi test was used to evaluate correlation between CPs and size of the ETT, number of days intubated prior to CP measurement, gender, and age.

RESULTS

Twenty pediatric subjects admitted during the study period were included for analysis. Eleven cuff measurements were found to be within normal limits, while 9 cuff measurements were found to be underinflated. No cases of overinflation were found. There were no significant associations between CP and size of the ETT (r = -0.08), number of days intubated prior to CP measurement (r = 0.19), gender (r = 0.09), and age (r = 0.12).

CONCLUSIONS

Our study suggests that endotracheal cuff underinflation occurs often in the PICU population. Strategies to ensure appropriate ETT CPs are maintained are essential in the intubated pediatric population. Additional studies are necessary to develop interventions and training focused on the use of a cuff pressure manometer to measure CPs in the PICU by respiratory therapists and ensure consistent measurement using inter rater evaluation processes are needed.

Age-based prediction of uncuffed tracheal tube size in children to prevent inappropriately large tube selection: a retrospective analysis

Background

This study aims to validate our previously reported prediction technique for uncuffed tracheal tube (TT) sizes in children younger than 2 years of age based on a calculated outer diameter (OD_Cal, mm) in each patient according to the regression equation OD_Cal = 0.00223 × age (day) + 4.88 and to investigate a better method to select initial TT sizes to decrease re-intubation frequency, especially since large tubes can damage the trachea.

Methods

We included patients younger than 2 years of age who underwent oral surgery under general anesthesia with tracheal intubation between July 2011 and December 2016 at the Osaka University Dental Hospital. The OD of the actual TT and the age in days were extracted from anesthesia records. Agreement rates, estimated numbers of required tubes, and size reduction frequencies were compared to obtain recommended OD (OD_Rec) values in 2 selection groups: “average selection” in the range “nearest to the OD_Cal value (OD_Cal - 0.35 < OD_Rec ≤ OD_Cal + 0.35)” and “safe selection” in the range “nearest to the value below OD_Cal (OD_Cal - 0.7 < OD_Rec ≤ OD_Cal)”.

Results

The agreement rates for an OD_Rec in the average selection and safe selection groups were 60.8 and 55.1%, respectively (P = 0.001). The estimated number of required tubes per patient were 1.40 ± 0.51 and 1.47 ± 0.55 (P < 0.001), respectively. The estimated frequencies of size reductions were 13.3 and 4.0% (P < 0.001), respectively.

Conclusions

Because the size reduction frequency is lower despite a slightly higher number of required TTs, selecting an OD_Rec based on “safe selection” parameters is desirable to avoid complications due to intubation with larger TTs.

Evidence Based Use of Cuffed Endotracheal Tubes in Children

Historically, the use of cuffed endotracheal tubes (ETTs) was reserved for children aged 8 years or older to minimize the risks of postextubation laryngeal edema. However, since publication of a 1997 study, researchers have consistently presented evidence that appropriately used cuffed ETTs are as safe as uncuffed ETTs. Because of the advantages of cuffed ETTs in the perianesthesia setting, the transition to cuffed ETTs in children is now complete. However, risks related to using cuffed ETTs in young children increase when guidelines for safe and appropriate use are not followed. Perianesthesia practitioners caring for children must understand the implications related to ETT type, correct ETT sizing, and the monitoring and control of ETT cuff pressure. The purpose of this educational module is to present evidence-based guidelines for the appropriate use of cuffed ETTs in children less than 8 years of age in the perianesthesia setting.

The incidence of postoperative respiratory complications: A retrospective analysis of cuffed vs uncuffed tracheal tubes in children 0-7 years of age

BACKGROUND

The use of cuffed vs uncuffed endotracheal tubes in pediatric anesthesia is widely debated. This study aimed to investigate whether the use of cuffed vs uncuffed tubes is associated with an increased incidence of acute postoperative respiratory complications.

METHODS

We retrospectively studied all children aged 0-7 years in which the trachea was intubated between September 28, 2006 and August 26, 2016 in a pediatric university hospital. Logistic regression analysis was performed to estimate the association between tube design (cuffed vs uncuffed) and the incidence of acute postoperative respiratory complications (stridor, wheezing, or dyspnea; desaturations ≤90%) in need of intervention (epinephrine, dexamethasone, nebulizers, supplementary oxygen, or reintubation), adjusting for potential confounders.

RESULTS

In 5247 of 6796 cases (77%), a cuffed tube was used. Acute postoperative respiratory complications in need of intervention occurred in 334 cases (4.9%) and were less common after cuffed than after uncuffed tubes (N = 236, 4.5% vs N = 98, 6.3%, respectively, odds ratio 0.70; 95%CI 0.55-0.89). Desaturation occurred less often after cuffed tubes (cuffed: N = 1365, 26.0%; uncuffed: N = 512, 33.1%; OR: 0.71 (0.61-0.84)). After adjusting for confounders, there was no difference in acute postoperative respiratory complications between cuffed tubes and uncuffed tubes (OR 0.74; 95%CI 0.55-1.01). Subgroup analyses in various age groups did not show significant differences between the use of cuffed or uncuffed tubes.

CONCLUSION

After adjustment for multiple confounders, the use of cuffed tubes was not associated with an increased incidence of acute respiratory complications in postanesthesia care unit.

Benefits of Using High-Volume-Low-Pressure Tracheal Tube in Children Undergoing Congenital Cardiac Surgery: Evidence From a Prospective Randomized Study

BACKGROUND

In the past 2 decades, usage of high-volume-low-pressure microcuffed tracheal tubes in smaller children has increased. However, there is paucity of evidence of its usage in smaller children undergoing congenital cardiac surgery. The aim of this study was to assess if microcuff endotracheal tubes in neonates and younger children undergoing congenital cardiac surgery is associated with better outcomes than uncuffed tubes.

METHODS

We carried out this single-center, prospective, randomized study between June and November 2016. Eighty patients were randomized into those receiving microcuff tracheal tubes and conventional uncuffed tubes. Primary outcome was stridor postextubation. Secondary outcomes measured included number of tube changes, volume of anesthetic gases required, and cost incurred.

RESULTS

The 2 groups were comparable in terms of baseline characteristics and duration of intubation. Incidence of stridor was significantly higher in conventional uncuffed tubes (12 [30%] vs 4 [10%]; P = .04) and so was the number of tube changes required (17/40 [42.5%] vs 2/40 [5%]; P ≤ .001). Tube change was associated with more than 3-fold risk of stridor (odds ratio = 3.92; 95% confidence interval = 1.23-12.43). Isoflurane (29.14 ± 7.01 mL vs19.2 ± 4.81 mL; P < .0001) and oxygen flow requirement ( P < .0001) and the resultant cost (7.46 ± 1.4 vs 5.77 ± 1.2 US$; P < .0001) were all significantly higher in the conventional uncuffed group.

CONCLUSION

Microcuff pediatric tracheal tube is associated with significantly lower incidence of stridor, tube changes, and anesthetic gas requirement. This leads to significant cost reduction that offsets the higher costs associated with usage of a microcuff tracheal tube.

Prediction of endotracheal tube size for pediatric patients from the epiphysis diameter of radius

Background

Using a too big or a too small size of an endotracheal tube in pediatric patients would result in tracheal injury or insufficient ventilation. Determining the appropriate endotracheal tube size is important because using an inappropriate size can cause complications. This study was performed to predict the appropriate endotracheal tube size by measuring the transverse diameter of the epiphysis of the distal radius under the assumption that the growth rates of cartilages in the entire body are close to each other.

Methods

Fifty-eight children aged 3 to 10 years who required general anesthesia were intubated with an uncuffed endotracheal tube. The tube size was considered to be appropriate when leaks occurred at inspiratory peak pressures between 10 to 25 mmHg. The transverse diameters of the epiphysis were measured with an ultra-sonogram at the distal radius and the proximal phalanx of the third finger and the fifth finger. Correlations and prediction probabilities of measurements were evaluated. The number needed to harm (NNH), which indicates the number of patients who need to be intubated for one patient who needs tube exchange, was investigated.

Results

The Spearman's correlation coefficient between the endotracheal tube size and the epiphysis of the distal radius was 0.814, which was the biggest coefficient. For epiphysis of the proximal phalanx of the third finger and the fifth finger, the correlation coefficient was 0.704 and 0.701, respectively. If the Cole's formula was applied for selection of the tube size, the NNH would be 7.

Conclusions

The appropriate endotracheal tube size could be predicted by means of the epiphyseal transverse diameter of the distal radius rather than the circumference measurements of the phalanx.

Impact of monitoring endotracheal tube cuff leak pressure on postextubation stridor in children

PURPOSE

To determine if implementing a protocol maintaining an air leak when using cuffed endotracheal tubes (ETT) throughout the course of mechanical ventilation (MV) in children would decrease the rate of postextubation stridor (PES).

METHODS

All children requiring MV through a cuffed ETT were included, except those with (1) upper airway anomaly, (2) died while on MV, (3) received tracheostomy before extubation, and (4) transferred before extubation. We implemented a protocol limiting the volume of air instilled into the cuff, allowing an air leak by 25 cm H₂O pressure or by peak inspiratory pressure, whichever was higher. Monitoring occurred every 6 hours, adjusting cuff volumes if necessary. Patients receiving nebulized racemic epinephrine within 24 hours of extubation for upper airway obstruction were defined as having PES.

RESULTS

At baseline, 110 patients received cuffed ETTs. The proportion of patients who had an air leak at the time of extubation was 47.3%, and that who developed PES was 21.8%. During the intervention, 101 patients received cuffed ETTs. Most (72.3%) had an air leak at the time of extubation (P< .01), and 9.9% developed PES, a 54.6% relative decrease (relative risk, 0.45; 95% confidence interval, 0.22-0.90; P= .018).

CONCLUSIONS

Maintaining an appropriate air leak throughout the course of MV using cuffed ETT decreases the rate of PES in children.

Comparisons of recursive partitioning analysis and conventional methods for selection of uncuffed endotracheal tubes for pediatric patients

BACKGROUND

Numerous studies have investigated the best method of selecting the appropriate size of endotracheal tube (ETT) for children. However, none of the methods or formulae for selection of ETT size have shown better prediction over another, and they have required complex formulae calculation or even use of cumbersome equipment. Recursive partitioning analysis creates a decision tree that is more likely to enable clearer and easier visualization of decision charts compared to other data mining methods.

OBJECTIVES

The aim of the current study was to develop a clinically practical and intuitive chart for prediction of ETT size.

METHODS

Pediatric patients aged 2-9 years undergoing general anesthesia were intubated with uncuffed ETT. The tube size was considered optimal when a tracheal leak was detected at an inflation pressure between 10 and 25 cmH2 O. The observed ETT size was compared with the predicted ETT size calculated using Cole's formula, multivariate regression analysis, ultrasonographic measurements, and recursive partitioning tree structure analysis. Preference among the prediction methods was also investigated by asking physicians about their preference of methods.

RESULTS

Correct prediction rates were 33.3%, 50%, 61.9%, and 59.5%, and close prediction rates were 61.9%, 83.3%, 88.1%, and 93.7% for Cole's formulae, multivariate regression analysis, ultrasonographic measurements, and recursive partitioning tree model, respectively. Fourteen of 16 physicians prefer to use the easy-to-interpret tree model.

CONCLUSIONS

Analysis of the tree model by recursive partitioning structure analysis accomplished a high correct and close prediction rate for selection of an appropriate ETT size. The intuitive and easy-to-interpret tree model would be a quick and helpful tool for selection of an ETT tube for pediatric patients.

Cuffed tracheal tubes in children: past, present and future

This article reviews recent developments and core topics in the use and design of pediatric cuffed tracheal tubes. A concept for an appropriate pediatric cuffed tracheal tube is introduced. The main points in this concept are evidence-based tracheal tube size recommendation, continuous cuff pressure monitoring and a pediatric tracheal tube with an anatomically-based intubation depth mark and a short distally placed high-volume-low pressure cuff made from an ultra-thin polyurethane membrane with markedly improved tracheal sealing performance. The main points in proper handling of cuffed tracheal tubes in children are highlighted. Finally, an outlook on future developments in the design of pediatric cuffed tracheal tubes and an overview of tasks to be performed in evaluating them is given.

Endoscopic airway findings in children with or without prior endotracheal intubation

BACKGROUND

Airway alterations found after endotracheal intubation are usually associated with mechanical trauma from the tube. However, no studies are available concerning alterations in airways that have never been intubated before. It was the aim of the study to compare endoscopic findings in the larynx and trachea of children who had undergone prior endotracheal intubation with findings in children who had not been intubated before.

METHODS

In 1021 children aged from 0 to 6 years, rigid endoscopies were performed before planned elective endotracheal intubation. The anonymized endoscopy videos were reviewed and graded by five international airway experts. Data was compared between the two groups using the chi-square test (P ≤ 0.05).

RESULTS

Endoscopic records of 971 children (473 with prior intubation; 498 without prior airway intubation) were included in the final calculations. Most patients (93.7%) with prior intubation had been intubated with a cuffed tube. The number of intubations ranged from 1 to 27. The median interval between intubation and endoscopy was 0.53 years (0.003-5.57 years). Abnormal findings were observed in 31.7% and 26.8% of patients with and without prior intubation, respectively (P = 0.063). Glottic granulomas were significantly more common after intubation (3.6% vs 1.4%; P = 0.028). The incidence of other abnormal findings was similar in both groups.

CONCLUSION

Endoscopic airway alterations can be observed in about one-quarter of children presenting for routine surgery without prior intubation. Except for glottic granulomas, the abnormalities are found with similar frequency in patients with and without prior intubation. No relevant airway damage from short-term endotracheal intubation was found.

Prospective randomized controlled multi-centre trial of cuffed or uncuffed endotracheal tubes in small children

BACKGROUND

The use of cuffed tracheal tubes (TTs) in small children is still controversial. The aim of this study was to compare post-extubation morbidity and TT exchange rates when using cuffed vs uncuffed tubes in small children.

METHODS

Patients aged from birth to 5 yr requiring general anaesthesia with TT intubation were included in 24 European paediatric anaesthesia centres. Patients were prospectively randomized into a cuffed TT group (Microcuff PET) and an uncuffed TT group (Mallinckrodt, Portex, Rüsch, Sheridan). Endpoints were incidence of post-extubation stridor and the number of TT exchanges to find an appropriate-sized tube. For cuffed TTs, minimal cuff pressure required to seal the airway was noted; maximal cuff pressure was limited at 20 cm H(2)O with a pressure release valve. Data are mean (SD).

RESULTS

A total of 2246 children were studied (1119/1127 cuffed/uncuffed). The age was 1.93 (1.48) yr in the cuffed and 1.87 (1.45) yr in the uncuffed groups. Post-extubation stridor was noted in 4.4% of patients with cuffed and in 4.7% with uncuffed TTs (P=0.543). TT exchange rate was 2.1% in the cuffed and 30.8% in the uncuffed groups (P<0.0001). Minimal cuff pressure required to seal the trachea was 10.6 (4.3) cm H(2)O.

CONCLUSIONS

The use of cuffed TTs in small children provides a reliably sealed airway at cuff pressures of <or=20 cm H(2)O, reduces the need for TT exchanges, and does not increase the risk for post-extubation stridor compared with uncuffed TTs.

Prophylactic administration of parenteral steroids for preventing airway complications after extubation in adults: meta-analysis of randomised placebo controlled trials

OBJECTIVE

To determine whether steroids are effective in preventing laryngeal oedema after extubation and reducing the need for subsequent reintubation in critically ill adults.

DESIGN

Meta-analysis.

DATA SOURCES

PubMed, Cochrane Controlled Trials Register, Web of Science, and Embase with no limitation on language, study year, or publication status. Selection criteria Randomised placebo controlled trials in which parenteral steroids were compared with placebo for preventing complications after extubation in adults. Review methods Search, application of inclusion and exclusion criteria, data extraction, and assessment of methodological quality, independently performed in duplicate. Odds ratios with 95% confidence intervals, risk difference, and number needed to treat were calculated and pooled.

PRIMARY OUTCOME

laryngeal oedema after extubation. Secondary outcome: subsequent reintubation because of laryngeal oedema.

RESULTS

Six trials (n=1923) were identified. Compared with placebo, steroids given before planned extubation decreased the odds ratio for laryngeal oedema (0.38, 95% confidence interval 0.17 to 0.85) and subsequent reintubation (0.29, 0.15 to 0.58), corresponding with a risk difference of -0.10 (-0.12 to -0.07; number needed to treat 10) and -0.02 (-0.04 to -0.01; 50), respectively. Subgroup analyses indicated that a multidose regimen of steroids had marked positive effects on the occurrence of laryngeal oedema (0.14; 0.08 to 0.23) and on the rate of subsequent reintubation (0.19; 0.07 to 0.50), with a risk difference of -0.19 (-0.24 to -0.15; 5) and -0.04 (-0.07 to -0.02; 25). In single doses there was only a trend towards benefit, with the confidence interval including 1. Side effects related to steroids were not found.

CONCLUSION

Prophylactic administration of steroids in multidose regimens before planned extubation reduces the incidence of laryngeal oedema after extubation and the consequent reintubation rate in adults, with few adverse events.

The endotracheal tube air leak test does not predict extubation outcome in critically ill pediatric patients

OBJECTIVE

Endotracheal tube air leak pressures are used to predict postextubation upper airway compromise such as stridor, upper airway obstruction, or risk of reintubation. To determine whether the absence of an endotracheal tube air leak (air leak test >/=30 cm H2O) measured during the course of mechanical ventilation predicts extubation failure in infants and children.

DESIGN

Prospective, blinded cohort.

SETTING

Multidisciplinary pediatric intensive care unit of a university hospital.

PATIENTS

Patients younger than or equal to 18 yrs and intubated >/=24 hrs.

INTERVENTIONS

The pressure required to produce an audible endotracheal tube air leak was measured within 12 hrs of intubation and extubation. Unless prescribed by the medical care team, patients did not receive neuromuscular blocking agents during air leak test measurements.

MEASUREMENTS AND MAIN RESULTS

The need for reintubation (i.e., extubation failure) was recorded during the 24-hr postextubation period. Seventy-four patients were enrolled resulting in 59 observed extubation trials. The extubation failure rate was 15.3% (9 of 59). Seven patients were treated for postextubation stridor. Extubation failure was associated with a longer median length of ventilation, 177 vs. 78 hrs, p = 0.03. Extubation success was associated with the use of postextubation noninvasive ventilation (p = 0.04). The air leak was absent for the duration of mechanical ventilation (i.e., >/=30 cm H2O at intubation and extubation) in ten patients. Absence of the air leak did not predict extubation failure (negative predictive value 27%, 95% confidence interval 6-60). The air leak test was >/=30 cm H2O before extubation in 47% (28 of 59) of patients yet 23 patients extubated successfully (negative predictive value 18%).

CONCLUSIONS

An endotracheal tube air leak pressure >/=30 cm H2O measured in the nonparalyzed patient before extubation or for the duration of mechanical ventilation was common and did not predict an increased risk for extubation failure. Pediatric patients who are clinically identified as candidates for an extubation trial but do not have an endotracheal tube air leak may successfully tolerate removal of the endotracheal tube.

Insights in pediatric ventilation: timing of intubation, ventilatory strategies, and weaning

PURPOSE OF REVIEW

Mechanical ventilation is a common intervention provided by pediatric intensivists. This fact notwithstanding, the management of mechanical ventilation in pediatrics is largely guided by a few pediatric trials along with careful interpretation and application of adult data.

RECENT FINDINGS

A low tidal volume, pressure limited approach to mechanical ventilation as established by the Acute Respiratory Distress Syndrome Network investigators, has become the prevailing practice in pediatric intensive care. Studies by these investigators suggest that high positive end expiratory pressure and recruitment maneuvers are not uniformly beneficial. High frequency oscillatory ventilation continues to be evaluated in an attempt to provide 'open lung' ventilation. Airway pressure release ventilation is a newer mode of ventilation that may combine the 'open lung' approach with spontaneous breathing. Prone positioning was demonstrated in a recent pediatric trial to have no effect on outcome, while calfactant was found to potentially improve outcomes in pediatric acute respiratory distress syndrome. Ventilator weaning protocols may not be as useful in pediatrics as in adults. Systemic corticosteroids decrease the incidence of post extubation stridor and may reduce reintubation rates.

SUMMARY

Mechanical ventilation with pressure limitation and low tidal volumes has become customary in pediatric intensive care units, and this lung protective approach will continue into the foreseeable future. Further investigation is warranted regarding use of high frequency oscillatory ventilation, airway pressure release ventilation, and surfactant to assist pediatric intensivists in application of these therapies.

The Air-Leak Test Is Not a Good Predictor of Postextubation Adverse Events in Children Undergoing Cardiac Surgery

OBJECTIVE

The air-leak test is recommended as a method of assessing the appropriate size of an uncuffed endotracheal tube (ETT) in children. The authors' primary objective was to determine whether the air-leak test would predict adverse events and reintubations after the removal of the ETT in children who have undergone cardiac surgery.

DESIGN

Prospective, observational, clinical study.

SETTING

University tertiary care hospital.

PATIENTS

Ninety-four children <10 years of age undergoing elective cardiac surgery requiring cardiopulmonary bypass surgery.

INTERVENTIONS

The attending anesthesiologist assessed air-leak pressure after intubation in the operating room (OR). In addition, the air-leak test was performed in 42 patients before extubation in the pediatric intensive care unit (PICU). The incidence of adverse events and the number of failed extubations were recorded after removal of the ETT.

MEASUREMENTS AND MAIN RESULTS

Eleven of the 94 patients were excluded from the study. Four (4.3%) of the patients died in the PICU before extubation, and 7 patients were excluded for other reasons. The median age of the 83 children was 0.9 years (range 0.01-9.6 years). The total incidences of postextubation adverse events and failed extubations were 30.1% and 8.4%, respectively. An audible air leak < or =25 cmH(2)O airway pressure during the OR phase or before removal of the ETT during the PICU recovery phase had no significant predictive value for the incidence of adverse events (p = 0.63) or reintubations (p = 1.0). The patients undergoing simple and complete operations compared with more complex and incomplete operations had significantly fewer postextubation adverse events (p = 0.03). Neonates did not have a higher risk for postextubation adverse events (p = 0.64) or reintubations (p = 0.26) than older children.

CONCLUSION

The air-leak test did not predict an increased risk for postextubation adverse events and reintubations in children undergoing elective congenital heart surgery.