Low dose of intravenous ketamine for prevention of hypotension after subarachnoid block

Abstract

Objectives and background: The study was conducted to know the efficacy of low dose i.v. ketamine for prevention of hypotension and to compare the hemodynamic changes following subarachnoid block with intrathecal bupivacaine heavy with or without low dose i.v. ketamine.Materials and Methods: 100 patients belonging to ASA-1 of both the sex (each group 50 patients n =50) undergoing General surgical and orthopaedic operations were randomly selected for the study.Results: The pulse rate in test group showed a slight increase at 20 minutes followed by a insignificant decrease during the subsequent one hour period. But in control group the pulse rate decreased to about 12% below the preoperative level showing a statistically very highly significant change. Systolic blood pressure in test group fell by a maximum of 7.29% when compared to control group where it fell to a maximum of 19.18% and diastolic blood pressure in test group fell by a maximum of 3.69% as compared to control group where the decrease was 12.28%. Thus the difference was statistically very highly significant.Conclusion: Low dose i.v. ketamine in doses of 0.3 mg/kg offers superior cardiovascular stability, and low dose i.v. ketamine in combination with midazolam, has good sedative and analgesic properties, reduces the volume of crystalloids required to maintain hemodynamic stability.