Comparative study between intra vascular administration of 6% heta starch, 3% heta starch & ringer lactate solution for prevention of hypotension during spinal anaesthesia

Background: Spinal anaesthesia is the more commonly administered procedure for pelvic, lower abdominal and lower limb procedures. It is popular because of simplicity and reliability of the technique as well as the relative rapidity with which adequate anaesthesia can be established. Hypotension is the most common complication of spinal anaesthesia. It results primarily from blockage of the sympathetic nervous system, which causes decrease in systemic vascular resistance and cardiac output. It is a common practice to give intravenous fluids, usually crystalloids, prior to central neuraxial block in order to prevent hypotension and this is usually referred as preloading, although the value of preloading with crystalloids is questioned. Aim of the Study: To compare the efficacy of a crystalloid to that of colloids in reducing the incidence and severity of hypotension in spinal anaesthesia, and also to find out if HES is a better colloid than ringer lactate. Methodology: A comparative study of volume preloading prior to subarachnoid block with Hetastarch (6%), Hetastarch (3%), Ringer`s lactate was undertaken at Osmania General Hospital, Hyderabad, after ethical committee clearance, institution approval and informed consent from the patients. Conclusion: It was observed from our study that 6% HES reduced the incidence of hypotension after spinal anaesthesia and also required lesser mean dose requirements of Mephentermine when compared to 3% HES and Ringer`s lactate. 3% HES when compared to Ringer`s lactate was better in terms of reducing the incidence and severity of hypotension following spinal anaesthesia.