Effects of tip-manipulated stylet angle on intubation using the GlideScope® videolaryngoscope in children: a prospective randomized controlled trial.

Lee, Ji-Hyun; Cho, Sung-Ae; Choe, Hyun-Woo; Ji, Sang-Hwan; Jang, Young-Eun; Kim, Eun-Hee; Kim, Jin-Tae; Kim, Hee-Soo

BACKGROUND An optimal endotracheal tube (ETT) curve can be a key factor in successful intubation using the GlideScope videolaryngoscope. AIMS This study aimed to evaluate the effects of tube tip-modified stylet curve on the intubation time in children METHODS: Children aged 1-5 years were randomly assigned to either the standard curve (group S, n=60) or tip-modified curve (group T, n=60) groups. In group S, the ETT curve was similar to that in the GlideScope. In group T, a point approximately 1.5 cm from the tube tip was additionally angled to the left by 15°-20°. The primary outcome was the total intubation time, and the secondary outcomes were incidence of successful intubation in the first attempt, number of additional manipulations of the stylet curve, and visual analogue scale (VAS) score for the easiness of intubation. RESULTS The mean total intubation time was significantly longer ingroup S than that in group T (13.9 [10.8] vs. 9.0 [3.4] sec, mean difference, 4.9 sec; 95% confidence interval [CI], 2.0-7.8; P=0.001). All patients in group T were successfully intubated in the first attempt whereas those in group S were not (100% vs. 93.3%, relative risk [RR], 0.11; 95% CI, 0.01-2.02; P=0.1376). Three patients in group S could be intubated after modifying the ETT curve similar to that in group T. Operators reported that tracheal intubation was easier in group T than in group S (median [interquartile range] for VAS; 1 [1-2] vs. 2 [1-3]; P<0.001) CONCLUSIONS: Having additional angle of the ETT tip to the left could be a useful technique to facilitate directing and advancing ETT into the vocal cords.