NEBULIZED BUPIVACAINE ATTENUATES THE HEART-RATE RESPONSE FOLLOWING TRACHEAL INTUBATION

Study Objective: To determine whether nebulized bupivacaine attenuates the acute hemodynamic response to laryngoscopy and intubation. Design : Prospective, randomized, placebo-controlled study. Setting: Operatin g room at a university medical center. Patients: 40 health ASA physica l status I and II patients scheduled for minor surgical procedures. In terventions: Patients were randomized to receive 4 ml of a nebulized s olution of either saline (n = 20) or 0.75% bupivacaine (n = 20) 15 min utes before induction of anesthesia. On completion of the aerosol trea tment, fentanyl 1.5 mu g/kg was given intravenously (IV), and 3 minute s later anesthesia was induced with thiopental sodium 5 mg/kg IV and s uccinylcholine 1.5 mg/kg IV. Laryngoscopy war begun 60 seconds after i nduction, and the trachea was intubated at 90 seconds. Anesthesia was maintained with 50% nitrous oxide in oxygen following intubation, and 1% isoflurane was administered at 180 seconds. Measurements and Main R esults: Heart rate (HR) and blood pressure were recorded automatically every 30 seconds for 5 minutes. Bupivacaine significantly attenuated HR (p < 0.05) but not the hypertensive response to laryngoscopy and in tubation. Conclusion: Nebulized 0.75% bupivacaine was only partially e ffective in blunting the hemodynamic response to tracheal intubation.