Vol 7, No 1 (2022)
Research paper
Published online: 2022-03-18

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Video-assisted versus macintosh direct laryngoscopy for intubation of obese patients: a meta-analysis of randomized controlled trials

Togay Evrin1, Lukasz Szarpak1, Burak Katipoglu1, Nataliia Mishyna2, Burce Serra Kockan3, Kurt Ruetzler4, Martin Schläpfer5
Disaster Emerg Med J 2022;7(1):30-40.


INTRODUCTION: We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) to compare the usefulness of video-assisted (VL) approaches with the Macintosh direct laryngoscope for endotracheal intubation of obese patients.
MATERIAL AND METHODS: Studies were obtained via a systematic search of SCOPUS, Medline, Web of Science, CINAHL, and the Cochrane Central databases. The polled relative risks (RRs) odds ratios (ODs) or standard mean differences (SMD) with 95% confidence intervals (CIs) were calculated with a random–effects model. Subgroup analyses were performed to evaluate the influence of VL types on the association.
RESULTS: First intubation attempt success rate in VL and DL group varied and amounted to 94.7% vs 89.5% respectively (OR = 2.04; 95% CI: 1.21–3.42; p = 0.007) and overall intubation success rate was 99.0% vs 97.5% respectively (OR = 2.20; 95% CI: 0.45–10.67; p = 0.33). Intubation time which was 48.0 ± 37.7 for VL and 48.4 ± 37.5 seconds for DL (SMD = 0.14; 95% CI: –0.33–0.61; p = 0.56). Cormack-Lehane 1 or 2 grade during intubation using VL was observed in 95.9% of cases and was statistically significantly higher than in the case of direct laryngoscopy (79.6%; OR = 6.68; 95% CI: 3.32–13.42; p < 0.001).
CONCLUSIONS: Our meta-analysis suggests that video-assisted intubation may be superior to conventional intubation in an obese patient population due to a higher first–attempt success rate, better glottis visibility, and a lower rate of intubation-related injuries.

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