Science, Medicine, and the Anesthesiologist

Endotracheal intubation has been traditionally performed in the operating room using direct laryngoscopy. Recently, video laryngoscopy has become widely available. Although it usually results in improved airway visualization, its effects on the successful passage of an endotracheal tube have not been systematically studied. This cluster-randomized multiple crossover trial at a single large U.S. academic hospital evaluated the success of either technique on the number of intubation attempts per surgical procedure (primary outcome). Secondary outcomes included intubation failure (switching to an alternative laryngoscopy device, or more than three intubation attempts), and a composite of airway and dental injuries. Adults (7,736 patients; 8,429 surgeries; median age, 66 yr (interquartile range, 56 to 73 yr); 35% female; 85% elective) undergoing elective or emergent cardiac, thoracic, or vascular surgery were studied; two groups of 11 operating rooms were randomized on a 1-week basis to either approach. The primary outcome was significantly reduced in the video laryngoscopy group (1.7% vs. 7.6%; estimated proportional odds ratio, 0.20 [95% CI, 0.14 to 0.28]; P < 0.001) as was intubation failure: 0.27% versus 4.0%; relative risk, 0.06; 95% CI, 0.03 to 0.14, P < 0.001; unadjusted absolute risk difference of −3.7% (95% CI, −4.4 to −3.2%). No difference in the composite injury variable was noted.

Take home message: This large, single-center, cluster-randomized multiple crossover trial demonstrates that the number of intubation attempts for induction of general anesthesia is significantly reduced with video compared to direct laryngoscopy in adult patients undergoing cardiac, thoracic, or vascular surgery.