Attenuation of hypertensive response to tracheal intubation with nitroglycerin.

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.