Postintubation croup in children

Cuffed versus uncuffed endotracheal tubes for neonates

BACKGROUND

Endotracheal intubation is a commonly performed procedure in neonates, the risks of which are well-described. Some endotracheal tubes (ETT) are equipped with a cuff that can be inflated after insertion of the ETT in the airway to limit leak or aspiration. Cuffed ETTs have been shown in larger children and adults to reduce gas leak around the ETT, ETT exchange, accidental extubation, and exposure of healthcare workers to anesthetic gas during surgery. With improved understanding of neonatal airway anatomy and the widespread use of cuffed ETTs by anesthesiologists, the use of cuffed tubes is increasing in neonates.

OBJECTIVES

To assess the benefits and harms of cuffed ETTs (inflated or non-inflated) compared to uncuffed ETTs for respiratory support in neonates.

SEARCH METHODS

We searched CENTRAL, PubMed, and CINAHL on 20 August 2021; we also searched trial registers and checked reference lists to identify additional studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs), quasi-RCTs, and cluster-randomized trials comparing cuffed (inflated and non-inflated) versus uncuffed ETTs in newborns. We sought to compare 1. inflated, cuffed versus uncuffed ETT; 2. non-inflated, cuffed versus uncuffed ETT; and 3. inflated, cuffed versus non-inflated, cuffed ETT.

DATA COLLECTION AND ANALYSIS

We used the standard methods of Cochrane Neonatal. Two review authors independently assessed studies identified by the search strategy for inclusion, extracted data, and assessed risk of bias. We used the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We identified one eligible RCT for inclusion that compared the use of cuffed (inflated if ETT leak greater than 20% with cuff pressure 20 cm H₂O or less) versus uncuffed ETT. The author provided a spreadsheet with individual data. Among 76 infants in the original manuscript, 69 met the inclusion and exclusion criteria for this Cochrane Review. We found possible bias due to lack of blinding and other bias. We are very uncertain about frequency of postextubation stridor, because the confidence intervals (CI) of the risk ratio (RR) were very wide (RR 1.36, 95% CI 0.35 to 5.25; risk difference (RD) 0.03, -0.11 to 0.18; 1 study, 69 participants; very low-certainty evidence). No neonate was diagnosed with postextubation subglottic stenosis; however, endoscopy was not available to confirm the clinical diagnosis. We are very uncertain about reintubation for stridor or subglottic stenosis because the CIs of the RR were very wide (RR 0.27, 95% CI 0.01 to 6.49; RD -0.03, 95% CI -0.11 to 0.05; 1 study, 69 participants; very low-certainty evidence). No neonate had surgical intervention (e.g. endoscopic balloon dilation, cricoid split, tracheostomy) for stridor or subglottic stenosis (1 study, 69 participants). Neonates randomized to cuffed ETT may be less likely to have a reintubation for any reason (RR 0.06, 95% CI 0.01 to 0.45; RD -0.39, 95% CI -0.57 to -0.21; number needed to treat for an additional beneficial outcome 3, 95% CI 2 to 5; 1 study, 69 participants; very low-certainty evidence). We are very uncertain about accidental extubation because the CIs of the RR were wide (RR 0.82, 95% CI 0.12 to 5.46; RD -0.01, 95% CI -0.12 to 0.10; 1 study, 69 participants; very low-certainty evidence). We are very uncertain about all-cause mortality during initial hospitalization because the CIs of the RR were extremely wide (RR 2.46, 95% CI 0.10 to 58.39; RD 0.03, 95% CI -0.05 to 0.10; 1 study, 69 participants; very low-certainty evidence). There is one ongoing trial. We classified two studies as awaiting classification because outcome data were not reported separately for newborns and older infants.

AUTHORS' CONCLUSIONS

Evidence for comparing cuffed versus uncuffed ETTs in neonates is limited by a small number of babies in a single RCT with possible bias. There is very low certainty evidence for all outcomes of this review. CIs of the estimate for postextubation stridor were wide. No neonate had clinical evidence for subglottic stenosis; however, endoscopy results were not available to assess the anatomy. Additional RCTs are necessary to evaluate the benefits and harms of cuffed ETTs (inflated and non-inflated) in the neonatal population. These studies must include neonates and be conducted both for short-term use (in the setting of the operating room) and chronic use (in the setting of chronic lung disease) of cuffed ETTs.

Central airway issues in bronchopulmonary dysplasia

While there is a very large focus on the abnormalities of parenchymal lung development and extensive efforts to minimize alveolar damage with "gentle ventilation" and noninvasive respiratory support for neonates with bronchopulmonary dysplasia (BPD), there is relatively little consideration for the implications of central airway disease in this patient population. There are significant changes in the structure and conformation of the central airway during the last half of gestation, and premature birth disrupts this natural developmental process. The arrest of maturation results in a smaller airway that is more compliant, easier to deform, and more susceptible to damage. Consequently, neonates with BPD are prone to developing central airway pathology, particularly for patients who require intubation and positive pressure ventilation. Central airway disease can be divided into dynamic and fixed airway obstruction and results in increased respiratory morbidity in neonates with chronic lung disease of prematurity.

Tracheal anomalies associated with Down syndrome: A systematic review

INTRODUCTION

Airway anomalies are accountable for a substantial part of morbidity and mortality in children with Down syndrome (DS). Although tracheal anomalies occur more often in DS children, a structured overview on the topic is lacking. We systematically reviewed the characteristics of tracheal anomalies in DS children.

METHODS

A MEDLINE and EMBASE search for DS and tracheal anomalies was performed. Tracheal anomalies included tracheal stenosis, complete tracheal ring deformity (CTRD), tracheal bronchus, tracheomalacia, tracheal web, tracheal agenesis or atresia, laryngotracheoesophageal cleft type 3 or 4, trachea sleeve, and absent tracheal rings.

RESULTS

Fifty-nine articles were included. The trachea of DS children is significantly smaller than non-DS children. Tracheomalacia and tracheal bronchus are seen significantly more often in DS children. Furthermore, tracheal stenosis, CTRD, and tracheal compression by vascular structures are seen regularly in children with DS. These findings are reflected by the significantly higher frequency of tracheostomy and tracheoplasty performed in DS children.

CONCLUSION

In children with DS, tracheal anomalies occur more frequently and tracheal surgery is performed more frequently than in non-DS children. When complaints indicative of tracheal airway obstruction like biphasic stridor, dyspnea, or wheezing are present in children with DS, diagnostic rigid laryngotracheobronchoscopy with special attention to the trachea is indicated. Furthermore, imaging studies (computed tomography, magnetic resonance imaging, and ultrasound) play an important role in the workup of DS children with airway symptoms. Management depends on the type, number, and extent of tracheal anomalies. Surgical treatment seems to be the mainstay in severe cases.

Severe stridor and profound weakness after cerebral malaria

Cerebral malaria (CM) is defined by WHO as coma (Blantyre Coma Score 2 or less) in a patient with Plasmodium falciparum parasitaemia and no alternative cause of coma identified. Mortality is approximately 15%-30% in African children and up to one-third of survivors have neurological sequelae. We present a patient with severe stridor and prolonged profound weakness during an intensive care admission with CM. These complications initially presented a diagnostic dilemma in our limited resourced setting. The stridor failed to improve with empiric steroids and a subsequent opportunistic ENT consult diagnosed vocal cord paresis. The weakness was so profound that the patient was unable to lift his head during the acute illness. The child received intensive physiotherapy, and at 1-month follow-up, the stridor and weakness had resolved.

Frequency of the requirement of inappropriate uncuffed tracheal tube size for pediatric patients: a retrospective observational analysis

BACKGROUND

The insertion of inappropriately sized uncuffed endotracheal tubes (ETTs) with a tight seal or presence of air leakage may be necessary in children. This study aimed to analyze the frequency of the requirement of inappropriately sized uncuffed ETT insertion, air leakage after the ETT was replaced with one of a larger size, and factors associated with air leakage after ETT replacement.

METHODS

Patients under 2 years of age who underwent oral surgery under general anesthesia with uncuffed ETTs between December 2013 and May 2015 were enrolled. The ETT size was selected at the discretion of the attending anesthesiologists. A leak test was performed after intubation. The ETT was replaced when considered necessary. Data regarding the leak pressure (P_Leak) and inspiratory and expiratory tidal volumes were extracted from anesthesia records. We considered a P_Leak of 10 < P_Leak ≤ 30 cmH₂O to be appropriate. The frequencies of the requirement of inappropriately sized ETTs, absence of leakage after ETT replacement, ETT size difference, and leak rate were calculated. A logistic regression was performed, with P_Leak, leak rate, and size difference included as explanatory variables and presence of leakage after replacement as the outcome variable.

RESULTS

Out of the 156 patients enrolled, 109 underwent ETT replacement, with the requirement of inappropriately sized ETTs being observed in 25 patients (23%). ETT replacement was performed in patients with P_Leak ≤ 10 cmH₂O; leakage was absent after replacement (P_Leak < 30 cmH₂O) in 52% of patients (25/48). In the multivariate logistic model, the leak rate before ETT replacement was significantly associated with the presence of leakage after replacement (p = 0.021).

CONCLUSIONS

Inappropriately sized ETTs were inserted in approximately 23% of the patients. The leak rate may be useful to guide ETT replacement.

Utility of Endotracheal Tube Cuff Pressure Monitoring in Mechanically Ventilated (MV) Children in Preventing Post-extubation Stridor (PES)

Objective

To study if protocolized monitoring of endotracheal tube (ETT) cuff pressure every 6 hours is better than adjusting endotracheal tube cuff inflation by the only bedside clinical assessment.

Materials and methods

This was a single-center prospective randomized controlled study done between July 1, 2017 and March 31, 2019. Children between 1 month and 18 years, intubated with cuffed ETT by our trained doctors were included. After obtaining consent, patients were randomized into two groups, standard group (SG) and cuff pressure monitoring group (MG). Sample size was calculated with 80 patients in each group with a power of 80%, significance level (alpha 0.05 and beta 0.2). In the SG, ETT cuff inflation was adjusted by clinical assessment (bedside minimal leak technique and monitoring the percentage of leak displayed on ventilator display) at 6 hours interval. In the MG, cuff pressures were monitored by the device every 6 hours to maintain between 20 and 25 mm Hg.

Results

Out of 543 mechanically ventilated children during the study period, 266 were eligible and randomized for study. During the study, 89 patients died and 17 were left against medical advice, leaving 80 patients in each group. Incidence of post-extubation stridor (PES), re-intubation rate, ventilator-associated pneumonia (VAP) rate, ventilator days, and length of pediatric intensive care unit (PICU) stay were analyzed and found no advantage of protocolized monitoring of cuff pressures in the reduction of any of the above variables.

Conclusion

Our findings if confirmed by large multicentric studies can bring an end to routine ETT cuff pressure measurements and emphasize more on clinical assessment. Clinical trial registry (CTRI/2019/05/019098).

Indian Journal of Critical Care Medicine (2021): 10.5005/jp-journals-10071-23737

How to cite this article

Shaikh F, Janaapureddy YR, Mohanty S, Reddy PK, Sachane K, Dekate PS, et al. Utility of Endotracheal Tube Cuff Pressure Monitoring in Mechanically Ventilated (MV) Children in Preventing Post-extubation Stridor (PES). Indian J Crit Care Med 2021;25(2):181–184.

Accuracy of stridor-based diagnosis of post-intubation subglottic stenosis in pediatric patients

OBJECTIVE

To assess the accuracy of stridor in comparison to endoscopic examination for diagnosis of pediatric post-intubation subglottic stenosis.

METHOD

Children who required endotracheal intubation for >24h were included in this prospective cohort study. Children were monitored daily and underwent flexible fiberoptic laryngoscopy after extubation. Those with moderate-to-severe abnormalities underwent another examination 7-10 days later. If lesions persisted or symptoms developed, laryngoscopy under general anesthesia was performed. Patients were assessed daily for stridor after extubation.

RESULTS

A total of 187 children were included. The incidence of post-extubation stridor was 44.38%. Stridor had a sensitivity of 77.78% (95% confidence interval [95% CI]: 51.9-92.6) and specificity of 59.18% (95% CI: 51.3-66.6) in detecting subglottic stenosis. The positive predictive value was 16.87% (95% CI: 9.8-27.1), and the negative predictive value was 96.15% (95% CI: 89.9-98.8). Stridor persisting longer than 72h or starting more than 72h post-extubation had a sensitivity of 66.67% (95% CI: 41.2-85.6), specificity of 89.1% (95% CI: 83.1-93.2), positive predictive value of 40.0% (95% CI: 23.2-59.3), and negative predictive value of 96.07% (95% CI: 91.3-98.4). The area under the receiver operating characteristic (ROC) curve was 0.78 (95% CI: 0.65-0.91).

CONCLUSIONS

Absence of stridor was appropriate to rule out post-intubation subglottic stenosis. The specificity of this criterion improved when stridor persisted longer than 72h or started more than 72h post-extubation. Thus, endoscopy under general anesthesia can be used to confirm subglottic stenosis only in patients who develop or persist with stridor for more than 72h following extubation.

Cuffed Versus Uncuffed Endotracheal Tubes in Pediatrics: A Meta-analysis

Background

Cuffed and uncuffed endotracheal tubes are commonly used for pediatric patients in surgery and emergency situations. It is still controversial which approach should be adopted. The purpose of the study was to compare the application of cuffed and uncuffed endotracheal tubes in pediatric patients.

Methods

We searched PubMed, Web of Science and Cochrane Library for clinical trials, which compared the two applications in children. The study characteristics and clinical data were summarized by two independent reviewers. Meta-analysis of the data was done using Revman 5.3 software.

Results

6 studies with 4141 cases were included in this meta-analysis. The pooling analysis showed that more patients need tube changes in uncuffed than cuffed tubes (OR: 0.07, 95% CI: 0.05-0.10, P < 0.00001). However, there were no differences on intubation duration, reintubation occurrence, accidental extubation rate, croup occurrence and racemic epinephrine use during the intubation process. Also we didn't find any differences on laryngospasm and stridor occurrence after extubation.

Conclusions

Our study demonstrated that uncuffed endotracheal tubes increased the need for tube changes. Other incidences or complications between the two groups had no differences. Cuffed tubes may be an optimal option for pediatric patients. But more trials are needed in the future.

Effectiveness of endotracheal-tube size by age-based formula for Thai pediatric cardiac patients: a retrospective study

Background: Pediatric patients with congenital heart diseases may have pathological airway abnormality and delayed development. To predict the appropriate size of endotracheal tube (ETT), a formula between diameter and age has been widely used for Western normal children. However, it is unclear whether this age-based (AB) formula is applicable to Thai pediatric cardiac patients. Objective: Evaluate the effectiveness of uncuffed ETT size by AB formula for pediatric cardiac patients. Methods: A retrospective study was conducted using 320 cases of non-cardiac and cardiac patients aged 2-7 years old who were orally intubated with a regular uncuffed ETT at Siriraj Hospital, Thailand. The exclusion criteria were history of tracheostomy, upper airway obstruction, and expected difficult intubation. Demographic data and final ETT used were recorded. Results: The tube- size predicted by the AB formula could be applied to 54.4% of non-cardiac and 48.1% of cardiac patients (p= 0.314), whereas three sizes of tubes (one above and one below the predicted size) covered 96.9% and 94.4% of non-cardiac and cardiac patients, respectively (p = 0.413). The ETT with 0.5 mm in ID larger than the predicted size were more often used in 35.0% of cardiac patients compared with 22.5% of non-cardiac patients (p= 0.019). There were no significant differences between methods using age (actual, round-up, and truncated) to calculate the AB formula. The Pearson’s correlation between the ID of the ETT with height in non-cardiac and cardiac patients were 0.430 and 0.683, respectively (p <0.001), whereas correlations with weight were 0.622 and 0.561 (p <0.001), respectively. Conclusion: The AB formula was applicable to non-cardiac and cardiac children aged 2-7 years old. For Thai pediatric cardiac patients, we recommend to use a one-size larger ETT than non-cardiac patients.

Pediatric Patients with High Pulmonary Arterial Pressure in Congenital Heart Disease Have Increased Tracheal Diameters Measured by Computed Tomography

OBJECTIVES

Determination of the appropriate tracheal tube size using formulas based on age or height often is inaccurate in pediatric patients with congenital heart disease (CHD), particularly in those with high pulmonary arterial pressure (PAP). Here, the authors compared tracheal diameters between pediatric patients with CHD with high PAP and low PAP.

DESIGN

Retrospective clinical study.

SETTING

Hospital.

PARTICIPANTS

Pediatric patients, from birth to 6 months of age, requiring general anesthesia and tracheal intubation who underwent computed tomography were included. Patients with mean pulmonary artery pressure >25 mmHg were allocated to the high PAP group, and the remaining patients were allocated to the low PAP group. The primary outcome was the tracheal diameter at the cricoid cartilage level, and the secondary goal was to observe whether the size of the tracheal tube was appropriate compared with that obtained using predictable formulas based on age or height.

MEASUREMENTS AND MAIN RESULTS

The mean tracheal diameter was significantly larger in the high PAP group than in the low PAP group (p < 0.01). Pediatric patients with high PAP required a larger tracheal tube size than predicted by formulas based on age or height (p = 0.04 for age and height).

CONCLUSIONS

Pediatric patients with high PAP had larger tracheal diameters than those with low PAP and required larger tracheal tubes compared with the size predicted using formulas based on age or height.

Postoperative Stridor following Repair of Tracheoesophageal Fistula: A Case Report

We report a case of prolonged post-operative stridor in a full-term neonate who was operated for tracheoesophageal fistula. Initial evaluation including an endoscopy and contrast-enhanced computed tomography scan was normal. Repeat endoscopic evaluation under anesthesia revealed tight aryepiglottic folds. Aryepiglottic split was performed and stridor improved dramatically. Tight aryepiglottic folds should be kept in differential diagnosis in a case of postoperative stridor in an infant.

Nebulized Fluticasone for Preventing Postextubation Stridor in Intubated Children: A Randomized, Double-Blind Placebo-Controlled Trial

OBJECTIVES

To evaluate the efficacy of nebulized fluticasone propionate in the prevention of postextubation stridor in children.

DESIGN

Double-blind, placebo-controlled randomized clinical trial.

SETTING

PICU in a tertiary referral center.

PATIENTS

Children 1 month to 15 years old who underwent mechanical ventilation.

INTERVENTIONS

Patients were randomly assigned into two groups after stratification based on age group receiving nebulized fluticasone 1,000 µg or normal saline solution, immediately after extubation. Vital signs and modified Westley score were evaluated for 6 hours after extubation. The primary outcome was the prevalence of postextubation stridor.

MEASUREMENTS AND MAIN RESULTS

One hundred forty-seven intubated children were enrolled into this study. Baseline characteristics between two groups were not different. There was no significant difference in the incidence of postextubation stridor (12/74 [16%] vs 13/73 [18%]; p = 0.797). However, when analyzing the subgroup of emergently intubated children, the fluticasone group had a longer delay median time for the initiation of noninvasive ventilation than the control group (380 [90-585] vs 60 [42-116] min; p = 0.044). The modified Westley scores at 30 and 60 minutes in the control group were significantly higher than the fluticasone group (4 vs 2, p = 0.04; 4.5 vs 0.5, p = 0.02, respectively).

CONCLUSIONS

The single dose of 1,000-µg nebulized fluticasone did not decrease the prevalence of postextubation stridor. However, it might be beneficial in emergently intubated children.

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.

Cuffed endotracheal tubes for neonates and young infants: a comprehensive review

Traditionally, uncuffed endotracheal tubes (ETTs) have been used for artificial ventilation of infants and children. More recently, newer designed high-volume low-pressure (HVLP) cuffed ETTs are being used with increasing frequency in infants from birth. Considering that many paediatric anaesthetists and intensivists are already using cuffed ETTs in infants >3 kg from birth, should neonatologists be doing the same? This review examines the reasons behind the traditional use of uncuffed ETTs and the problems associated with their use; newer HVLP cuffed ETTs and what they can potentially offer neonates; and reviews evidence from studies comparing the use of cuffed and uncuffed ETTs in neonates and small infants.

The effect of deep vs. awake extubation on respiratory complications in high-risk children undergoing adenotonsillectomy: a randomised controlled trial

CONTEXT

There is ongoing debate regarding the optimal timing for tracheal extubation in children at increased risk of perioperative respiratory adverse events, particularly following adenotonsillectomy.

OBJECTIVE

To assess the occurrence of perioperative respiratory adverse events in children undergoing elective adenotonsillectomy extubated under deep anaesthesia or when fully awake.

DESIGN

Prospective, randomised controlled trial.

SETTING

Tertiary paediatric hospital.

PATIENTS

One hundred children (<16 years), with at least one risk factor for perioperative respiratory adverse events (current or recent upper respiratory tract infection in the past 2 weeks, eczema, wheezing in the past 12 months, dry nocturnal cough, wheezing on exercise, family history of asthma, eczema or hay fever as well as passive smoking).

INTERVENTION

Deep or awake extubation.

MAIN OUTCOME MEASURE

The occurrence of perioperative respiratory adverse events (laryngospasm, bronchospasm, persistent coughing, airway obstruction, desaturation <95%).

RESULTS

There were no differences between the two groups with regard to age, medical and surgical parameters. The overall incidence of complications did not differ between the two groups; tracheal extubation in fully awake children was associated with a greater incidence of persistent coughing (60 vs. 35%, P = 0.028), whereas the incidence of airway obstruction relieved by simple airway manoeuvres in children extubated while deeply anaesthetised was greater (26 vs. 8%, P = 0.03). There was no difference in the incidence of oxygen desaturation lasting more than 10 s.

CONCLUSION

There was no difference in the overall incidence of perioperative respiratory adverse events. Both extubation techniques may be used in high-risk children undergoing adenotonsillectomy provided that the child is monitored closely in the postoperative period.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12609000387224.

Respiratory complications in the pediatric postanesthesia care unit

This article focuses on common respiratory complications in the postanesthesia care unit (PACU). Approximately 1 in 10 children present with respiratory complications in the PACU. The article highlights risk factors and at-risk populations. The physiologic and pathophysiologic background and causes for respiratory complications in the PACU are explained and suggestions given for an optimization of the anesthesia management in the perioperative period. Furthermore, the recognition, prevention, and treatment of these complications in the PACU are discussed.

Pediatric upper airway obstruction: interobserver variability is the road to perdition

PURPOSE

The purposes of the study are to determine the interobserver variability in the clinical assessment of pediatric upper airway obstruction (UAO) and to explore how variability in assessment of UAO may contribute to risk factors and incidence of postextubation UAO.

MATERIALS

This is a prospective trial in 2 tertiary care pediatric intensive care units. Bedside practitioners performed simultaneous, blinded UAO assessments on 112 children after endotracheal extubation.

RESULTS

Agreement among respiratory therapists, pediatric intensive care nurses, and pediatric intensive care physicians was poor for cyanosis (κ = 0.01) and hypoxemia at rest (κ = 0.14) and fair for consciousness (κ = 0.27), air entry (κ = 0.32), hypoxemia with agitation (κ = 0.27), and pulsus paradoxus (κ = 0.23). When looking at "stridor" and "retractions," defined using more than 2 grades of severity from the Westley Croup Score, the interrelater reliability was moderate (κ = 0.43 and κ = 0.47, respectively). This could be improved marginally by dichotomizing the presence or absence of stridor (κ = 0.54) or retractions (κ = 0.53). The overall incidence of UAO after extubation (stridor plus retractions) could range from 7% to 22%, depending on how many providers were required to agree.

CONCLUSIONS

Physical findings routinely used for UAO have poor interobserver reliability among bedside providers. This variability may contribute to inconsistent findings regarding incidence, risk factors, and therapies for postextubation UAO.

Scientific rationale for the use of alpha-adrenergic agonists and glucocorticoids in the therapy of pediatric stridor

Purpose. The most common pharmacological therapies used in the treatment of stridor in children are glucocorticosteroids (GC) and alpha-adrenergic (αAR) agonists. Despite the long-standing reported efficacy of these medications, there is a paucity of data relating to their actual mechanisms of action in the upper airway. Summary. There is compelling scientific evidence supporting the use of αAR-agonists and GCs in pediatric stridor. αAR signaling and GCs regulate the vasomotor tone in the upper airway mucosa. The latter translates into better airflow dynamics, as delineated by human and nonhuman upper airway physiological models. In turn, clinical trials have demonstrated that GCs and the nonselective αAR agonist, epinephrine, improve respiratory distress scores and reduce the need for further medical care in children with stridor. Future research is needed to investigate the role of selective αAR agonists and the potential synergism of GCs and αAR-signaling in the treatment of upper airway obstruction and stridor.

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.

Corticosteroids for the prevention and treatment of post-extubation stridor in neonates, children and adults

BACKGROUND

Post-extubation stridor may prolong length of stay in the intensive care unit, particularly if airway obstruction is severe and re-intubation proves necessary. Some clinicians use corticosteroids to prevent or treat post-extubation stridor, but corticosteroids may be associated with adverse effects ranging from hypertension to hyperglycaemia, so a systematic assessment of the efficacy of this therapy is indicated.

OBJECTIVES

To determine whether corticosteroids are effective in preventing or treating post-extubation stridor in critically ill infants, children, or adults.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL and reference lists of articles. The most recent searches were conducted in January 2009.

SELECTION CRITERIA

Randomized controlled trials comparing administration of corticosteroids by any route with placebo in infants, children, or adults receiving mechanical ventilation via an endotracheal tube in an intensive care unit.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trial quality and extracted data.

MAIN RESULTS

Eleven trials involving 2301 people were included: six in adults, two in neonates, three in children. All but one examined use of steroids for the prevention of post-extubation stridor; the remaining one concerned treatment of existing post-extubation stridor in children. Patients were drawn from heterogeneous medical/surgical populations. Dexamethasone given intravenously at least once prior to extubation was the most common steroid regimen utilized (uniformly in neonates and children). In neonates the two studies found heterogeneous results, with no overall statistically significant reduction in post extubation stridor (RR 0.42; 95% CI 0.07 to 2.32). One of these studies was on high-risk patients treated with multiple doses of steroids around the time of extubation, and this study showed a significant reduction in stridor. In children, the two studies were clinically heterogeneous. One study included children with underlying airway abnormalities and the other excluded this group. Prophylactic corticosteroids tended to reduce reintubation and significantly reduced post-extubation stridor in the study that included children with underlying airway abnormalities (N = 62) but not in the study that excluded these children (N = 153). In six adult studies (total N = 1953), the use of prophylactic corticosteroid administration did not significantly reduce the risk of re-intubation (RR 0.48; 95% CI 0.19 to 1.22). While there was a significant reduction in the incidence of post extubation stridor (RR 0.47; 95% CI 0.22 to 0.99), there was significant heterogeneity (I(2)=81%, X(2)=26.36, df=5, p<0.0001). Subgroup analysis revealed that post extubation stridor could be reduced in adults with a high likelihood of post extubation stridor when corticosteroids were administered as multiple doses begun 12-24 hours prior to extubation compared to single doses closer to extubation; the test for interaction for multiple versus single doses indicated RRR 0.22 (95% CI 0.10 to 0.47) for stridor with multiple doses. Side effects were uncommon and could not be aggregated.

AUTHORS' CONCLUSIONS

Using corticosteroids to prevent (or treat) stridor after extubation has not proven effective for neonates or children. However, given the consistent trends towards benefit, this intervention does merit further study, particularly for high risk children or neonates. In adults, multiple doses of corticosteroids begun 12-24 hours prior to extubation do appear beneficial for patients with a high likelihood of post extubation stridor.

Corticosteroids for the prevention and treatment of post-extubation stridor in neonates, children and adults

BACKGROUND

Post-extubation stridor may prolong length of stay in the intensive care unit, particularly if airway obstruction is severe and re-intubation proves necessary. Corticosteroids, however, may be associated with adverse effects ranging from hypertension to hyperglycemia, and a more systematic assessment of the efficacy of this therapy is indicated prior to widespread adoption of this practice.

OBJECTIVES

To determine whether corticosteroids are effective in preventing or treating post-extubation stridor in critically ill infants, children, or adults.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL and reference lists of articles. The most recent searches were conducted in April 2007.

SELECTION CRITERIA

Randomized controlled trial comparing administration of corticosteroids by any route with placebo in infants, children, or adults receiving mechanical ventilation via an endotracheal tube in an intensive care unit.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trial quality and extracted data.

MAIN RESULTS

Ten trials involving 2230 people were included: five in adults, two in neonates, three in children. All but one examined use of steroids for the prevention of post-extubation stridor; the remaining one concerned treatment of existing post-extubation stridor in children. Patients were drawn from heterogeneous medical/surgical populations. Dexamethasone given intravenously at least once prior to extubation was the most common steroid regimen utilized (uniformly in neonates and children). In neonates the two studies found heterogeneous results, but there was an overall non significant reduction in post extubation stridor (RR 0.42; 95% CI 0.07 to 2.32). This decrease was seen only in the study on high-risk patients treated with multiple doses of steroids around the time of extubation. In children, the two studies were clinically heterogeneous. One study included children with underlying airway abnormalities and the other excluded this group. Prophylactic corticosteroids tended to reduce reintubation and significantly reduced post-extubation stridor in the study that included children with underlying airway abnormalities (N = 62) but not in the study that excluded these children (N = 153). In five adult studies (total N = 1873), there was a non significant trend for prophylactic corticosteroid administration to reduce the risk of re-intubation (RR 0.47; 95% CI 0.16 to 1.39) and post extubation stridor (RR 0.49; 95% CI 0.20 to 1.19). These reductions were largely due to two studies that utilized repeated doses of methylprednisolone 12 to 24 hours prior to extubation. Side effects were uncommon and could not be aggregated.

AUTHORS' CONCLUSIONS

Using corticosteroids to prevent (or treat) stridor after extubation has not proven effective for neonates, children or adults. However, given the consistent trends towards benefit, this intervention does merit further study.

Dexamethasone to prevent postextubation airway obstruction in adults: a prospective, randomized, double-blind, placebo-controlled study

Introduction

Prophylactic steroid therapy to reduce the occurrence of postextubation laryngeal edema is controversial. Only a limited number of prospective trials involve adults in an intensive care unit. The purpose of this study was to ascertain whether administration of multiple doses of dexamethasone to critically ill, intubated patients reduces or prevents the occurrence of postextubation airway obstruction. Another specific objective of our study was to investigate whether an after-effect (that is, a transient lingering benefit) exists 24 hours after the discontinuation of dexamethasone.

Methods

A randomized, placebo-controlled, double-blind trial was conducted in an adult medical intensive care unit of a tertiary care hospital. Eighty-six patients who had been intubated for more than 48 hours with a cuff leak volume (CLV) of less than 110 ml and who met weaning criteria were randomly assigned to receive either dexamethasone (5 mg; n = 43) or placebo (normal saline; n = 43) every six hours for a total of four doses on the day preceding extubation. CLV was measured before the first injection, one hour after each injection, and 24 hours after the fourth injection. Extubation was carried out 24 hours after the last injection. Postextubation obstruction (defined as the presence of stridor) was recorded within 48 hours of extubation.

Results

Administration of dexamethasone during the 24-hour period preceding extubation resulted in a statistically significant increase in the CLV (p < 0.05). The significant increase of CLV and change of CLV relative to baseline tidal volume (percentage) occurred not only throughout the treatment period, but also 24 hours after the last dexamethasone injection. The incidence of postextubation stridor was significantly lower in the dexamethasone group than in the placebo group (10% [4/40] versus 27.5% [11/40]; p = 0.037), whereas there was no significant difference in reintubation rate between the two groups (2.5% [1/40] versus 5% [2/40]; p = 0.561).

Conclusion

Prophylactic administration of multiple-dose dexamethasone is effective in reducing the incidence of postextubation stridor in adult patients at high risk for postextubation laryngeal edema. The after-effect of dexamethasone may validate the reduced incidence of postextubation stridor after multiple doses of dexamethasone.

Trial registration

NCT00452062.

Evaluation of cuffed tracheal tube size predicted using the Khine formula in children

BACKGROUND

The correct size of cuffed endotracheal tube (CET) limits the risk of postintubation tracheal damage. The aim of this study was to compare the size of the CET used in children with the size predicted by the Khine formula [age (years)/4 + 3].

METHODS

After ethical committee approval, 204 children aged 1 day-15 years were included prospectively in the study. The choice of the size of the CET was made at the discretion of the attending anesthesiologist. The main criterion of judgment was the comparison of the leak before and after inflating the cuff at a pressure of 20 cm.H(2)O. Demographic data, tracheal tube size used and that predicted by Khine's formulae and side-effects were recorded.

RESULTS

Overall, 21% of the CET were in accordance with the size predicted by the Khine formula. In the remaining patients, 72% were oversized and 7% undersized. In 12 cases, the size of CET chosen initially was modified: for a larger size in eight children and for a smaller size in four others. Six children (2.9%) presented with minor postoperative complications.

CONCLUSIONS

Our data suggest that Khine's formula for predicting the appropriate tracheal tube size underestimates optimal size by 0.5 mm. We therefore recommend the use of the following formula: internal diameter of the CET = [age/4 + 3.5] in children >1 year of age which may be applied without increased risk of complications. The rate of tracheal reintubation as well as the detected leaks supports these recommendations.

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.

Recent developments in airway management of the paediatric patient

PURPOSE OF THE REVIEW

During the last two years, several studies have enhanced our knowledge about the influence of pharmacological agents and routine airway management manoeuvres on the airway of paediatric patients. New supraglottic airway devices have been introduced into routine paediatric anaesthesia practice, and the design of paediatric endotracheal tubes has been modified. This review summarizes the most recent and relevant scientific developments in paediatric airway management.

RECENT FINDINGS

Strong evidence has been gained that the lateral position is the best to ensure a clear airway in anaesthetized or sedated spontaneously breathing children. Remifentanil has emerged as an appealing drug for airway management in anaesthetized or sedated children. The paediatric ProSeal-Laryngeal mask airway offers important advantages over the Classic-Laryngeal mask airway for supraglottic airway management. The newly designed Microcuff paediatric endotracheal tube offers an improved age-appropriate design.

SUMMARY

Remifentanil has found a place in airway management in paediatric patients. Recent improvements in the design of paediatric supraglottic airway devices and endotracheal tubes are promising. Further research is needed to consolidate their role in improving the perioperative outcome in paediatric patients.

Anesthesia for the Child with an Upper Respiratory Tract Infection: Still a Dilemma?

One of the most controversial issues in pediatric anesthesia has revolved around the decision to proceed with anesthesia and surgery for the child who presents with an upper respiratory tract infection (URI). In the past, doctrine dictated that children with URIs have their surgery postponed until the child was symptom free. This practice was based on the empirically supported premise that anesthesia increased the risk of serious complications and complicated the child's postoperative course. Although recent clinical data confirm that some children with URIs are at increased risk of perioperative complications, these complications can, for the most part, be anticipated, recognized, and treated. Although the child with a URI still presents a challenge, anesthesiologists are now in a better position to make informed decisions regarding the assessment and management of these children, such that blanket cancellation has now become a thing of the past.

The "air leak" test around the endotracheal tube, as a predictor of postextubation stridor, is age dependent in children

OBJECTIVES

The airleak test is measured with a manometer as the pressure necessary to generate an audible airleak around the endotracheal tube. Our objectives were to determine whether the airleak test predicts postextubation stridor in children and if age affects its sensitivity and specificity.

DESIGN

A retrospective study.

SETTING

Pediatric intensive care unit.

PATIENTS

We studied all intubated patients admitted to our pediatric intensive care unit between July 1998 and December 1999. Patients were excluded if they had acute viral croup, tracheal surgery, hypotonic airway, or vocal cord paralysis or if they died before extubation.

INTERVENTIONS

Medical records were reviewed for patient demographics, presence of an airleak on the day of extubation, airleak values, presence of postextubation stridor, and extubation failure secondary to upper airway obstruction.

MEASUREMENTS AND MAIN RESULTS

One hundred and five patients met our inclusion criteria and had an airleak test at the time of extubation. In children <7 yrs of age, the incidence of postextubation stridor was similar in patients with or without an airleak at >20 mm Hg (50% vs. 67.7%; >.05) with a sensitivity of 65.6% (95% confidence interval, 46.9-80.8). In children >or=7 yrs of age, the incidence of postextubation stridor was greater in patients with an airleak at >20 mm Hg (55.5% vs. 5.8%; p=.01) with a sensitivity of 83.3% (95% confidence interval, 36.8-99) in predicting postextubation stridor.

CONCLUSIONS

Our study suggests that the airleak test has a low sensitivity when used as a screening test to predict postextubation stridor in young children (<7 yrs old), whereas in older children (>or=7 yrs old) the airleak test may predict postextubation stridor.

Corticosteroids for the prevention of reintubation and postextubation stridor in pediatric patients: A meta-analysis

OBJECTIVE: To determine whether corticosteroids are effective in preventing or treating postextubation stridor and in reducing the need for subsequent reintubation of the trachea in critically ill infants and children. DESIGN: Meta-analysis of published randomized controlled trials. DATA SOURCES: References of each trial from a MEDLINE search were reviewed, and experts in the field were contacted. STUDY SELECTION: Any randomized controlled trial comparing the administration of corticosteroids with placebo on the prevalence of reintubation or postextubation stridor in infants or children receiving mechanical ventilation via an endotracheal tube in an intensive care unit. DATA EXTRACTION: Data extraction and methodologic quality assessment were assessed independently by two reviewers. DATA SYNTHESIS: Six controlled clinical trials met the criteria for inclusion; three trials pertain to neonates and three to children. Five trials examined the use of steroids for the prevention of reintubation (four of these evaluated postextubation stridor specifically); one trial examined the use of steroids to treat existing postextubation stridor in children. There was a nonsignificant trend toward a decreased rate of reintubation in all subjects when prophylactic steroids were used (n = 376, relative risk [RR] = 0.34, 95% confidence interval [CI] = 0.05-2.33). Prophylactic use of steroids reduced postextubation stridor in the pooled studies (n = 325, RR = 0.50, 95% CI = 0.28-0.88). In young children, there were significant reductions of postextubation stridor with preventive treatment (n = 216, RR = 0.53, 95% CI = 0.28-0.97), and a trend toward less stridor was observed in neonates (n = 109, RR = 0.42, 95% CI = 0.07-2.32). There was a nonsignificant trend toward a reduced reintubation rate when steroids were used to treat existing upper airway obstruction requiring reintubation (RR = 0.55, 95% CI = 0.17-1.78). Side effects were seldom reported and could not be evaluated. CONCLUSIONS: Prophylactic administration of dexamethasone before elective extubation reduces the prevalence of postextubation stridor in neonates and children and may reduce the rate of reintubation.

The use of dexamethasone in the prevention of postextubation stridor in pediatric patients in PICU/NICU settings: an analytical review

ISSUES AND PURPOSE

Dexamethasone has been used to prevent postextubation stridor in children, but its use is controversial. Five randomized, controlled clinical trials were reviewed to analyze the effectiveness of prophylactic dexamethasone on postextubation stridor in pediatric patients.

CONCLUSIONS

Previous studies had inconsistent results. Several factors may contribute to postextubation stridor in pediatric patients. Postextubation stridor and extubation failure do not always result from airway edema.

PRACTICE IMPLICATIONS

In addition to prophylactic dexamethasone, other approaches should be used to prevent postextubation stridor, such as preparing the patient, following established guidelines, and providing appropriate postextubation care.

Perioperative considerations for the child with an upper respiratory tract infection

The decision to cancel or proceed with elective surgery for the child with an upper respiratory tract infection (URI) has been a source of debate among pediatric anesthesiologists, nurse anesthetists, and perianesthesia nurses for many years. Although some studies suggest that anesthesia for the child with a URI increases the risk of perioperative respiratory complications, others suggest that these complications are easily managed and are not associated with any adverse sequelae. This article describes the pathogenesis of viral respiratory tract infections, reviews the literature regarding anesthesia and URIs, and discusses the assessment and management of the child who presents for elective surgery while harboring a URI. It is hoped that this information will be important to perianesthesia nurses and anesthesia providers in making decisions regarding proceeding or cancelling surgery for children with URIs and in optimizing their perioperative management.

Perioperative management issues in pediatric patients

Recent developments in perioperative practice, emphasizing issues that are of greatest concern in pediatric patients, are reviewed in this article. Many areas bear further evaluation in the evolving field of perioperative medicine: Effective techniques of psychologic preparation for children and their parents in an era in which the family rarely encounters the hospital environment before the day of surgery Application of newer intraoperative anesthetics, such as new narcotics and muscle relaxants, to shorten PACU and pediatric ICU stay while maintaining safety and comfort Critical evaluation of current methods of pain management to optimize comfort, while minimizing cost of such management in an increasingly cost-conscious health care environment The recent advent of a process for credentialing pediatric anesthesia fellowship programs, which requires a research component, bodes well for the prospect of finding answers to some of these questions.

Down syndrome: analysis of airway size and a guide for appropriate intubation

OBJECTIVES/HYPOTHESIS

The purpose of this study is to prospectively evaluate the airway size of children with Down syndrome (DS). Previous studies have observed an increase in postintubation stridor in children with DS. Anesthetic literature suggests using a smaller endotracheal tube in children with DS, but more specific recommendations are not offered. With this study, recommendations are presented for the appropriate endotracheal tube size to use in children with DS undergoing intubation.

STUDY DESIGN

A prospective, nonrandomized study was performed on a cohort of 42 children with DS and 32 control subjects. Sizing of the airway was assessed through measurement of an air leak around the endotracheal tube at intubation. The size of the airway was also evaluated through measurements of the tracheal diameter at the "tracheotomy point" on magnetic resonance imagine (MRI) studies of the head and neck which were performed on a group of children with DS. These were compared with normative values of the tracheal diameter in children.

METHODS

The proper size of endotracheal tube in a population of children with DS and in a group of normal controls was determined. The "proper size" of an endotracheal tube was defined as that size of tube which allowed an audible air leak around the tube between 10 and 30 cm of H2O pressure. Anesthetic technique was controlled and identical for all study subjects. Participants had no previous history of airway compromise, stridor, or previous intubation. Weight and age were recorded and evaluated for their influence on the results. A retrospective evaluation was made of MRI studies of the neck that were performed on children with DS. Using measurement techniques described by Reed et al., the tracheal diameters at the "tracheostomy point" were compared with normative values for children. Measurements were both obtained by the author and confirmed by a pediatric radiologist.

RESULTS

Using this prescribed method to determine the proper size of endotracheal tube, the control group used endotracheal tubes that were predicted from established anesthesia charts and formulas. However, children with DS required endotracheal tubes at least two sizes smaller. Age was found to be a more reliable factor in predicting the endotracheal tube size. A table of endotracheal tube sizes for intubation in children with DS is presented. Evaluation of the tracheal diameter at the tracheotomy point revealed that children with DS have a smaller trachea when compared with control children. It is not only the subglottis that is smaller; the tracheal diameter as well must be assumed to be of a smaller diameter in children with DS.

CONCLUSIONS

Children with DS have smaller airways than other children. This is because of an overall decrease in the diameter of the tracheal lumens. Initial intubation of a child with DS should be performed with an endotracheal tube at least two sizes smaller than would be used in a child of the same age without DS, to avert potential trauma to the airway.

Predictive factors for complications in children with laryngeal damage at extubation

OBJECTIVES

To determine which factors contribute to early complications when intubated children show macroscopic lesions at extubation.

STUDY DESIGN

Retrospective review of 96 consecutive medical records of children aged 1 day to 15 years. Patients were divided into three groups depending on the extent of the subsequent treatment required: medical, reintubation, and surgical.

METHODS

Age, sex, clinical history, and macroscopic features of the lesions were collected and data were compared in each group.

RESULTS

Underlying noninfectious respiratory diseases and young age were found to be risk factors for higher incidence of complications, but not prolonged or multiple intubations. Edema, especially in the glottic area, was a risk factor for surgical treatment. Multiple lesions were risk factors for reintubation.

CONCLUSIONS

History of intubation, its cause, and lesions discovered at extubation can provide the basis for definition of an "at risk" profile for intubated children.

Nebulized racemic epinephrine for extubation of newborn infants

BACKGROUND

Following a period of mechanical ventilation, post-extubation upper airway obstruction can occur in newborn infants, especially after prolonged, traumatic or multiple intubations. The subsequent increase in upper airway resistance may lead to respiratory insufficiency and failure of extubation. The vasoconstrictive properties of epinephrine, and its proven efficacy in the treatment of croup in infants, has led to the routine use of inhaled nebulised epinephrine immediately post-extubation in some neonatal units. It is also recommended for neonates with post-extubation tracheal obstruction and stridor in neonatal and respiratory textbooks and reviews.

OBJECTIVES

The primary objective was to assess whether nebulised epinephrine administered immediately after extubation in neonates weaned from IPPV decreases the need for subsequent additional respiratory support.

SEARCH STRATEGY

Searches were made of Medline (MeSH search terms 'epinephrine' and 'exp infant, newborn'), the Oxford Database of Perinatal trials, expert informants and journal hand searching mainly in the English language, expert informant searches in the Japanese language by Prof. Ogawa, previous reviews including cross references, abstracts, and conference and symposia proceedings.

SELECTION CRITERIA

All randomised and quasi-randomised control trials in which nebulised epinephrine was compared with placebo immediately post-extubation in newborn infants who have been weaned from IPPV and extubated, with regard to clinically important outcomes (i.e. need for additional respiratory support, increase in oxygen requirement, respiratory distress, stridor or the occurrence of side effects).

DATA COLLECTION AND ANALYSIS

No studies met our criteria for inclusion in this review.

MAIN RESULTS

No studies were identified which looked at the effect of inhaled nebulised epinephrine on clinically important outcomes in infants being extubated.

REVIEWER'S CONCLUSIONS

IMPLICATIONS FOR PRACTICE

There is no evidence either supporting or refuting the use of inhaled nebulised racemic epinephrine in newborn infants.

IMPLICATIONS FOR RESEARCH

randomised controlled trials are needed comparing inhaled nebulised racemic epinephrine with placebo in neonates post-extubation. This should be looked at both as a routine treatment post-extubation and as specific treatment for post-extubation upper airway obstruction. Study populations should include the group of infants at highest risk for upper airway obstruction from mucosal swelling because of their small glottic and sub-glottic diameters (ie those infants with birthweights less than 1000 grams).

Protective effect of 3-aminobenzamide, an inhibitor of poly (ADP-ribose) synthetase, against laryngeal injury in rats

The effect of 3-aminobenzamide, an inhibitor of poly (ADP-ribose) synthetase activity, was evaluated in a rat model of laryngeal injury induced by endotracheal intubation for 1 h. At 1 h after extubation, the laryngeal damage was characterized by areas of mucosal necrosis, submucosal edema, swelling of subglottic glands, and submucosal infiltration of inflammatory cells. Activity of myeloperoxidase, a marker of neutrophil infiltration, was also markedly increased into the damaged tissue. Immunohistochemistry for nitrotyrosine, an index of nitrosative stress, showed an intense staining in the inflamed larynx. Treatment with 3-aminobenzamide (10 mg/kg intraperitoneally) significantly reduced the appearance of mucosal damage and was associated with a significant reduction of tissue myeloperoxidase activity and nitrotyrosine immunoreactivity in the larynx. The results of this study suggest that poly (ADP-ribose) synthetase may play a role in the inflammatory process after laryngeal intubation and extubation, and administration of 3-aminobenzamide may be a beneficial therapeutic approach.

Postextubation laryngeal edema: a review with consideration for home discharge

Respiratory complications occurring in the immediate postoperative period are well known to the seasoned postanesthesia care unit nurse. The most common adverse respiratory events originating in this setting are airway obstruction, hypoventilation, hypoxemia, and pulmonary aspiration of gastric contents. The focus of this article details airway compromise secondary to edema of the larynx and adjacent structures as a consequence of translaryngeal intubation. Postextubation laryngeal edema is a relatively rare problem; however, severe episodes may have life-threatening ramifications. A review of pertinent airway anatomy and airflow dynamics as they relate to this compromised airway condition is presented. Risk factors for the development of postextubation laryngeal edema plus contemporary patient treatment strategies will be reinforced. Patient management issues are addressed, with emphasis placed on the ambulatory patient in which discharge to a remote location is anticipated.