GlideScope video laryngoscopy versus direct laryngoscopy in the emergency department: a propensity score-matched analysis

OBJECTIVE: To evaluate whether the use of a GlideScope video laryngoscope (GVL) improves first-attempt intubation success compared with the Macintosh laryngoscope (MAC) in the emergency department (ED). DESIGN: A propensity score-matched analysis of data from a prospective multicentre ED airway registry—the Korean Emergency Airway Management Registry (KEAMR). SETTING: 4 academic EDs located in a metropolitan city and a province in South Korea. PARTICIPANTS: A total of 4041 adult patients without cardiac arrest who underwent emergency intubation from January 2007 to December 2010. OUTCOME MEASURES: The primary and secondary outcomes were successful first intubation attempt and intubation failure, respectively. To reduce the selection bias and potential confounding effects, we rigorously adjusted for the baseline differences between two groups using a propensity score matching. RESULTS: Of the 4041 eligible patients, a GVL was initially used in 540 patients (13.4%). Using 1:2 propensity score matching, 363 and 726 patients were assigned to the GVL and MAC groups, respectively. The adjusted relative risks (95% CIs) for the first-attempt success rates with a GVL compared with a MAC were 0.76 (0.56 to 1.04; p=0.084) and the respective intubation failure rates 1.03(0.99 to 1.07; p=0.157). Regarding the subgroups, the first-attempt success of the senior residents and attending physicians was lower with the GVL (0.47 (0.23 to 0.98), p=0.043). In the patients with slight intubation difficulty, the first-attempt success was lower (0.60 (0.41 to 0.88), p=0.008) and the intubation failure was higher with the GVL (1.07 (1.02 to 1.13), p=0.008). CONCLUSIONS: In this propensity score-matched analysis of data from a prospective multicentre ED airway registry, the overall first-attempt intubation success and failure rates did not differ significantly between GVL and MAC in the ED setting. Further randomised controlled trials are needed to confirm our findings.