Assessment of Efficacy and safety of Granisetron in Preventing Hypotension Following Spinal Anaesthesia in Patients Undergoing Elective Caesarean Section in a Tertiary Care Hospital of Bihar

Background: Subarachnoid block (SAB) or spinal anaesthesia is the most commonly used anaesthesia technique for conducting caesarean section. Although subarachnoid block is considered safe, it is associated with high risk of hypotension specially in elective caesarean section. The selective 5-hydroxytrptamine-3 (5-HT3) receptors are also present peripherally in the form of cardiac chemoreceptors on sensory component of vagal nerve endings and also in the wall of right and left ventricles. So, action of serotonin on these 5-HT3 receptors results in decrease in blood pressure and heart rate. Aim/Objective: To assess the efficacy and safety of intravenous granisetron in prevention of hypotension and bradycardia following spinal anaesthesia in parturients undergoing lower segment caesarean section (LSCS). Materials and method: Parturients were randomized into two groups using a web generated random number. Granisetron group patients received IV Granisetron 1mg and Saline group patients received IV 5ml of 0.9% normal saline. Both the groups received the allocated drug solution intravenously 10 minutes before administration of SAB. A fall in the systolic blood pressure below 100mmHg or a fall in mean arterial blood pressure of more than 20% from baseline was considered as hypotension and managed with 6mg bolus of intravenous mephenteramine. Results: More events of hypotension were observed in saline group (74%) than granisetron group (34%) with statistically significant difference (p005). Similarly, both groups were comparable with respect to duration of surgery, intra-operative and post-operative complications. Conclusion: Our study results showed that granisetron is effective in decreasing incidence of hypotension in parturients undergoing elective caesarean section under spinal anaesthesia in addition to its anti-emetic effect which is its main indication without any risk of significant intra-operative or post-operative negative outcomes.