Comparison of Indirect and Direct Laryngoscopes in Pediatric Patients with a Difficult Airway: A Systematic Review and Meta-Analysis

Abstract

This meta-analysis was performed to determine whether an indirect laryngoscope is more advantageous than a direct laryngoscope for tracheal intubation in the setting of a difficult pediatric airway. Data on the intubation failure and intubation time during tracheal intubation were extracted from prospective and retrospective studies identified through a comprehensive literature search. Data from 10 individual articles (11 trials) were combined, and a DerSimonian and Laird random-effects model was used to calculate either the pooled relative risk (RR) or the weighted mean difference (WMD) and the corresponding 95% confidence interval (CI). Meta-analysis of the 10 articles indicated that the intubation failure of tracheal intubation with an indirect laryngoscope was not significantly different from that of a direct laryngoscope in patients with a difficult airway (RR 0.86, 95% CI 0.51-1.46; p = 0.59; Cochrane's Q = 50.5; I² = 82%). Intubation time with an indirect laryngoscope was also similar to that with a direct laryngoscope (WMD 4.06 s; 95% CI -1.18-9.30; p = 0.13; Cochrane's Q 39.8; I² = 85%). In conclusion, indirect laryngoscopes had the same intubation failure and intubation time as direct laryngoscopes in pediatric patients with a difficult airway. Currently, the benefits of indirect laryngoscopes have not been observed in the setting of a difficult pediatric airway.

Keywords: difficult airway; direct laryngoscopes; indirect laryngoscopes; meta-analysis; pediatric.

Figure 1

Meta-analysis flow chart. RCT, randomized controlled trial.

Figure 2

Forest plot of intubation failure for tracheal intubation using the indirect laryngoscope compared with the direct laryngoscope [5,7,8,18,19,20,21,22,23,24].

Figure 3

Forest plot of intubation time for tracheal intubation using the indirect laryngoscope compared with the direct laryngoscope [5,19,20,21,22,24].

Figure 4

Forest plot of adverse event for tracheal intubation using the indirect laryngoscope compared with the direct laryngoscope [5,7,8,20,21,24,25].

Figure 5

The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

Figure 6

The risk of bias assessment. Green circles, red circles, and yellow circles indicate “low risk of bias”, “high risk of bias”, and “unclear risk of bias”, respectively [5,7,8,18,19,20,22,23,24].