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

BACKGROUND: The most commonly used drug for total intravenous anesthesia (TIVA) is ketamine which results in cardiovascular stimulation. AIMS: The primary aim of this study was to assess the effect of oral clonidine premedication on attenuating the hemodynamic responses following ketamine administration. SETTINGS AND DESIGNS: This was a prospective, observational, comparative study conducted in a tertiary care institution. SUBJECTS AND METHODS: 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. STATISTICAL ANALYSIS USED: 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. RESULTS: 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. CONCLUSION: Oral premedication with clonidine 150 μg, administered 60 min before the conduct of TIVA, attenuated hemodynamic responses of intravenous ketamine.