Difficult laryngoscopy, complication and difficult intubation according to cricoid pressure during tracheal intubation
| Outcome | Overall cohort | PS 2 matched cohort | ||
|---|---|---|---|---|
| No cricoid pressure (n=696) | Cricoid pressure (n=499) | p Value* | Risk difference (95% CI) | |
| Difficult laryngoscopy (n, %) | 112 (17) | 66 (13) | ||
| Risk difference (95% CI) | −0.03 (−0.07 to 0.01) | 0.001 (−0.07 to 0.08) | ||
| Complication (n, %) | 69 (10) | 84 (17) | <0.001 | 0.04 (−0.06 to 0.15) |
| Oesophageal intubation | 34 (5) | 29 (6) | 0.47 | 0.05 (−0.03 to 0.13) |
| Desaturation | 14 (2) | 40 (8) | <0.001 | −0.005 (−0.05, 0.04) |
| Mainstem intubation | 16 (2) | 18 (4) | 0.17 | 0.016 (−0.02 to 0.05) |
| Trauma | 4 (1) | 11 (2) | 0.01 | 0.03 (0.002 to 0.05) |
| Vomiting, aspiration during intubation | 5 (1) | 14 (3) | 0.004 | 0.02 (−0.006 to 0.05) |
| Bronchospasm, laryngospasm | 6 (1) | 1 (0) | 0.27 | −0.005 (−0.03 to 0.02) |
| Difficult intubation (n, %) | 283 (41) | 190 (38) | 0.36 | 0.06 (−0.13 to 0.25) |
*Bonferroni correction for multiple tests (ie, p values multiplied by the number of comparisons, ie, eight).
Treatment effect is expressed as risk differences (95% CIs). Difficult laryngoscopy defined according to the Cormack and Lehane grade III or IV obtained by direct laryngoscopy and based on the structures seen. Difficult intubation defined as two or more failed laryngoscopic attempts, or the need for any alternative methods.
PS, propensity score.