Oral Clonidine Premedication Attenuates Hemodynamic Responses of Ketamine during Total Intravenous Anesthesia

The most commonly used drug for total intravenous anesthesia (TIVA) is ketamine which results in cardiovascular stimulation.

The primary aim of this study was to assess the effect of oral clonidine premedication on attenuating the hemodynamic responses following ketamine administration.

This was a prospective, observational, comparative study conducted in a tertiary care institution.

A total of 40 female patients aged 18-55 years who were posted for elective short gynecological procedures under TIVA were recruited for this study. Group A patients were given oral clonidine 150 μg 60 min before proposed surgical procedure, whereas Group B patients received a placebo tablet. Before induction, all patients received glycopyrrolate 0.2 mg, midazolam 2 mg, and fentanyl 2 μg/kg intravenously. Anesthesia was induced with ketamine 1.5 mg/kg body weight intravenously over 2-3 min. The hemodynamics after premedication and induction were assessed.

To test the statistical significance or difference between the mean change from the basal value at various time points, student's t-test was applied.

At 20, 30, 40, 50, and 60 min postpremedication and after induction at 1, 3, 5, 10, 15, 20, and 30 min, Group B showed significantly higher heart rate. Systolic and diastolic blood pressures showed a significant decrease in Group A after induction up to 30 min. Nearly 6.7% of the patients in Group B had emergence delirium with none in Group A, which was not statistically significant.

Oral premedication with clonidine 150 μg, administered 60 min before the conduct of TIVA, attenuated hemodynamic responses of intravenous ketamine.