Comparison of the Hemodynamic Effects of Lidocaine and Propranolol during Laryngoscopy and Endotracheal Intubation in Hypertensive Patients

Purpose: We sought to compare the hemodynamic effects of Lidocaine and Propranolol during endotracheal intubation and laryngoscopy in hypertensive patients. Materials and methods: In a double-blind prospective clinical trial, 90 hypertensive patients with the American Society of Anesthesiologists (ASA) class I and II, who were candidated for general anesthesia, were recruited. All the patients were anesthetized with the same method after 2 minutes of parenteral premedication, including Diazepam (0.01 mg/kg) and Morphine (0.1 mg/kg). The patients randomly received one of the medications, 1.5mg/kg of Lidocaine (n=30), 0.01-0.015 mg/kg of IV Propranolol (n=30), or 5 ml of normal saline (n=30). Then anesthesia was induced. After 3 minutes, laryngoscopy and tracheal intubation was done. The patients’ heart rates, diastolic and systolic blood pressure, mean arterial pressure, arrhythmia, tearing, and sweating were recoded. Results: Mean arterial blood pressure and heart rates were decreased after premedication in all the groups and increased after intubation respectively. In the Propranolol group, the increase of mean arterial blood pressure was very significant but the increase in heart rates was not significant. In the Lidocaine group, there was a slight increase in the mean arterial blood pressure after intubation, but the increase in heart rates was significant. Conclusion: Although the administration of Propranolol 3 minutes before laryngoscopy and intubation significantly prevented a rise in the heart rate in the hypertensive patients, it was not successful in preventing an increase in the mean arterial blood pressure. Lidocaine was effective in preventing a rise in the mean arterial blood pressure; however, it exerted a negligible effect on controlling heart rate increase