This Month in ANESTHESIOLOGY

While several risk factors have been identified as leading to laryngeal injury during general anesthesia, the quality of endotracheal intubation has not been clearly implicated. Accordingly, Mencke et al. recruited 80 healthy volunteers scheduled to undergo elective ear surgery and randomly assigned them to one of two groups. The first group received 0.5 mg/kg atracurium prior to intubation, while the second group received a saline preparation. The anesthesiologist performing the intubations was blinded as to study drugs, and the induction regimen with propofol and fentanyl was standardized for both groups of patients. Intubation techniques were evaluated and scored according to the consensus conference on Good Clinical Research Practice (GCRP) in Pharmacodynamic Studies of Neuromuscular Blocking Agents. An independent observer also assessed and recorded other parameters, including visualization of the vocal cords, time to intubation, and number of intubation attempts. In the postanesthesia care unit (PACU), an investigator blinded to group assignment evaluated patients for hoarseness, and recorded any vocal cord sequelae, including thickening of vocal folds, edema, or hematoma. Of the final 73 evaluable patients, the rate of excellent intubation scores was significantly higher in the group receiving atracurium as opposed to saline. In the group receiving atracurium, postoperative hoarseness was limited to time spent in the PACU, while postoperative hoarseness persisted into the postoperative period in 5 patients from the saline group. Fifty patients in the saline group had evidence of some vocal cord sequelae (VCS) postoperatively, while only 5 from the atracurium group had VCS. In patients for whom the intubating conditions had been rated excellent, there was less frequent postoperative hoarseness and VCS. Adding atracurium to the propofol/fentanyl induction regimen significantly improved the quality of endotracheal intubation and reduced postoperative laryngeal morbidity. Building on these results, additional research could be conducted to determine the best timing of intubation for individual patients (based on neuromuscular monitoring) and to develop special strategies for prevention and treatment of PH in patients who use their voices professionally. [Editor-in-Chief’s comment: Direct laryngoscopy/endotracheal intubation is perhaps the single most common procedure performed by anesthesiologists (other than the insertion of IV catheters). The procedure is now so routine that while we worry about our failures to secure the airway, we have largely ignored the possible adverse consequences of our success in placing a plastic tube through the vocal cords. We’ve all told patients that “your hoarseness is due to that tube we put in your throat—don’t worry, it will go away.” However, that hoarseness is unquestionably the result of at least some degree of laryngeal injury, and hoarseness that doesn’t resolve before PACU discharge should (perhaps) be viewed as a serious laryngeal injury. Our colleagues in otolaryngology also tell us that patients with even more severe dysfunction are not rare. One major problem is that so little work has been done to carefully define the true incidence of laryngeal injury and dysfunction in routine patients, or to define the mechanisms of such dysfunction. Even less work has been done to determine if variations in technique might reduce the incidence of injury/dysfunction; the article by Mencke et al. that is summarized above is one of the few. I would encourage interested young investigators to consider the potential value of further work in this area. A more thorough editorial concerning this issue will also be forthcoming in a few months.]