Laryngeal morbidity and quality of tracheal intubation: a randomized controlled trial

Abstract

Background: Vocal cord sequelae and postoperative hoarseness during general anesthesia are a significant source of morbidity for patients and a source of liability for anesthesiologists. Several risk factors leading to laryngeal injury have been identified in the past. However, whether the quality of tracheal intubation affects their incidence or severity is still unclear.

Methods: Eighty patients were randomized in two groups (n = 40 for each) to receive a propofol-fentanyl induction regimen with or without atracurium. Intubation conditions were evaluated with the Copenhagen Score; postoperative hoarseness was assessed at 24, 48, and 72 h by a standardized interview; and vocal cords were examined by stroboscopy before and 24 and 72 h after surgery. If postoperative hoarseness or vocal cord sequelae persisted, follow-up examination was performed until complete restitution.

Results: Without atracurium, postoperative hoarseness occurred more often (16 vs. 6 patients; P = 0.02). The number of days with postoperative hoarseness was higher when atracurium was omitted (25 vs. 6 patients; P < 0.001). Similar findings were observed for vocal cord sequelae (incidence of vocal cord sequelae: 15 vs. 3 patients, respectively, P = 0.002; days with vocal cord sequelae: 50 vs. 5 patients, respectively, P < 0.001). Excellent intubating conditions were less frequently associated with postoperative hoarseness compared to good or poor conditions (11, 29, and 57% of patients, respectively; excellent vs. poor: P = 0.008). Similar findings were observed for vocal cord sequelae (11, 22, and 50% of patients, respectively; excellent vs. poor: P = 0.02).

Conclusions: The quality of tracheal intubation contributes to laryngeal morbidity, and excellent conditions are less frequently associated with postoperative hoarseness and vocal cord sequelae. Adding atracurium to a propofol-fentanyl induction regimen significantly improved the quality of tracheal intubation and decreased postoperative hoarseness and vocal cord sequelae.