Cricoid Pressure Does Not Increase the Rate of Failed Intubation by Direct Laryngoscopy in Adults
ABSTRACT Cricoid pressure (CP) is applied during induction of anesthesia to prevent regurgitation of gastric content and pulmonary aspiration. However, it has been suggested that CP makes tracheal intubation more difficult. This double-blind randomized study evaluated the effect of CP on orotracheal intubation by direct laryngoscopy in adults.
Seven hundred adult patients undergoing general anesthesia for elective surgery were randomly assigned to have a standardized CP (n = 344) or a sham CP (n = 356) during laryngoscopy and intubation. After anesthesia induction and complete muscle relaxation, a 30-s period was allowed to complete intubation with a Macintosh No. 3 laryngoscope blade. The primary endpoint was the rate of failed intubation at 30 s. The secondary endpoints included the intubation time, the Cormack and Lehane grade of laryngoscopic view, and the Intubation Difficulty Scale score.
Groups were similar for demographic data and risk factors for difficult intubation. The rates of failed intubation at 30 s were comparable for the two groups: 15 of 344 (4.4%) and 13 of 356 (3.7%) in the CP and sham CP groups, respectively (P = 0.70). The grades of laryngoscopic view and the Intubation Difficulty Scale score were also comparable. Median intubation time was slightly longer in the CP group than in the sham CP group (11.3 and 10.4 s, respectively, P = 0.001).
CP applied by trained personnel does not increase the rate of failed intubation. Hence CP should not be avoided for fear of increasing the difficulty of intubation when its use is indicated.
- SourceAvailable from: Alexis F Turgeon
Article: REPORTS OF ORIGINAL INVESTIGATIONS[Show abstract] [Hide abstract]
ABSTRACT: Effect of manual in-line stabilization of the cervical spine in adults on the rate of difficult orotracheal intubation by direct laryngoscopy: a randomized controlled trial Effet de la stabilisation en ligne de la colonne cervicale sur l'incidence d'intubations orotrachéales difficiles par laryngoscopie directe chez l'adulte: une étude randomisée contrôlée Abstract Purpose Although manual in-line stabilization (MILS) is commonly used during endotracheal intubation in patients with either known or suspected cervical spine instability, the effect of MILS on orotracheal intubation is poorly documented. This study evaluated the rate of failed tra-cheal intubation in a fixed time interval with MILS. Methods Two hundred elective surgical patients were randomized into two groups. In the MILS group, the patient's head was stabilized in a neutral position by grasping the patient's mastoid processes to minimize any head movement during tracheal intubation. In the control group, the patient's head rested in an optimal position for tracheal intubation. A 30-sec period was allowed to com-plete tracheal intubation with a #3 Macintosh laryngoscope blade. The primary endpoint was the rate of failed tracheal intubation at 30 sec. Secondary endpoints included tracheal intubation time and the Cormack & Lehane grade of laryngoscopy. Results Patient characteristics were similar with respect to demographic data and risk factors for difficult tracheal intubation. The rate of failed tracheal intubation at 30 sec was 50% (47/94) in the MILS group compared to 5.7% (6/ 105) in the control group (P \ 0.0001). Laryngoscopic grades 3 and 4 were more frequently observed in the MILS group. Mean times for successful tracheal intubation were 15.8 ± 8.5 sec and 8.7 ± 4.6 sec for the MILS and control groups, respectively (mean difference 7.1, CI 95% 5.0–9.3, P \ 0.0001). All patients who failed tracheal intubation in the MILS group were successfully intubated when MILS was removed. Conclusion In patients with otherwise normal airways, MILS increases the tracheal intubation failure rate at 30 sec and worsens laryngeal visualization during direct laryngoscopy.