CLINICAL OUTCOME OF CONTINUOUS FACIAL-NERVE MONITORING DURING PRIMARYPAROTIDECTOMY

Objectives: To assess whether continuous facial nerve monitoring durin g parotidectomy is associated with a lower incidence of facial nerve p aresis or paralysis compared with parotidectomy without monitoring and to assess the cost of such monitoring. Design: ii retrospective analy sis of outcomes for patients who underwent parotidectomy with or witho ut continuous facial nerve monitoring. Setting: University medical cen ter. Patients: Fifty-six patients undergoing parotidectomy in whom con tinuous electromyographic monitoring was used and 61 patients in whom it was not used. Main Outcome Measures: (1) The incidence of early and persistent facial nerve paresis or paralysis and (2) the cost associa ted with facial nerve monitoring.Results: Early, unintentional facial weakness was significantly lower in the group monitored by electromyog rapy (43.6%) than in the unmonitored group (62.3%) (P=.04). In the sub group of patients without comorbid conditions or surgeries, early weak ness in the monitored group (33.3%) remained statistically lower than the rate of early weakness in the unmonitored group (57.5%) (P=.03). T here was rio statistical difference in the final facial nerve function or incidence of permanent nerve injury between the groups or subgroup s. After multivariate analysis, nonmonitored status (odds ratio [OR], 3.22), advancing age (OR, 1.47 per 10 years), and longer operative tim es (OR, 1.3 per hour) were the only significant independent predictive variables significantly associated with early postoperative facial we akness. The incremental cost of facial nerve monitoring was $379. Conc lusions: The results suggest that continuous electromyographic monitor ing of facial muscle during primary parotidectomy reduces the incidenc e of shortterm postoperative facial paresis. Advantages and disadvanta ges of this technique need to be considered together with the addition al costs in deciding whether routine use of continuous monitoring is a useful, cost-effective adjunct to parotid surgery.