Attenuation of hypertensive response to tracheal intubation with nitroglycerin

Abstract

Study objective: To evaluate the efficacy and safety of intravenous (IV) nitroglycerin in attenuating the hypertensive response to laryngoscopy and intubation as a new application of the drug.

Design: Controlled, randomized, double-blind study.

Setting: University hospital.

Patients: Thirty normotensive patients (ASA physical status I) undergoing elective surgery were divided into three groups of ten patients each.

Interventions: Anesthesia was induced with thiopental sodium 5 mg/kg i.v., and tracheal intubation was facilitated with vecuronium 0.2 mg/kg i.v. During anesthesia, ventilation was assisted or controlled with 1% enflurane and 50% nitrous oxide in oxygen. Either 1.5 micrograms/kg of nitroglycerin, 2.5 micrograms/kg of nitroglycerin, or saline (control) was administered IV simultaneously with the start of laryngoscopy (lasting 30 seconds), which was attempted 2 minutes after administration of thiopental sodium and vecuronium.

Measurements and main results: Patients receiving saline showed a significant increase in mean arterial pressure and rate-pressure product associated with tracheal intubation. These increases following tracheal intubation were significantly reduced in nitroglycerin-treated patients compared with those in the control group (p < 0.05).

Conclusion: A single, rapid IV dose of nitroglycerin is a simple, practical, effective, and safe method to attenuate the hypertensive response to laryngoscopy and tracheal intubation.