Comparison of Direct and Video Laryngoscopy in Patients with Restricted Cervical Spine Movement

Abstract

Background: Tracheal intubation in patients with restricted cervical spine movement is challenging because immobilisation may impair glottic visualisation and increase intubation difficulty. Video laryngoscopy may provide improved laryngeal visualisation without requiring substantial alignment of the airway axes. This study compared conventional Macintosh direct laryngoscopy with McGrath video laryngoscopy during manual in-line stabilisation.

Methods: This prospective randomized comparative study included 100 adult patients undergoing elective surgery under general anaesthesia. Patients were randomly allocated to Macintosh direct laryngoscopy (Group DL, n=50) or McGrath video laryngoscopy (Group VL, n=50). Cervical spine movement was restricted using manual in-line stabilisation. The primary outcome was time to successful tracheal intubation. Secondary outcomes included Cormack–Lehane grade, POGO score, first-attempt success, Intubation Difficulty Scale (IDS), requirement for optimisation manoeuvres, haemodynamic changes, and airway-related complications.

Results: Cormack–Lehane grade I view was obtained in 76.0% of patients with McGrath compared with 42.0% with Macintosh, while the mean POGO score was significantly higher with McGrath (86.2 ± 13.7% vs 67.4 ± 20.1%; p<0.001). First-attempt success was significantly greater with McGrath (94.0% vs 80.0%; p=0.037), and the median IDS score was lower [1 (IQR 0–2) vs 2 (IQR 1–4); p<0.001]. Optimisation manoeuvres were required less frequently with McGrath (16.0% vs 42.0%; p=0.004). Mean intubation time was comparable between the groups (48.9 ± 16.2 vs 43.6 ± 14.8 seconds; p=0.091). Haemodynamic responses and airway-related complications were also comparable.

Conclusion: McGrath video laryngoscopy provided superior glottic visualisation, higher first-attempt success, and easier intubation with fewer optimisation manoeuvres than conventional Macintosh direct laryngoscopy during cervical spine immobilisation. However, intubation time, haemodynamic responses, and airway-related complications were comparable between the techniques.