Comparison of ramosetron, ondansetron, and granisetron in attenuating maternal hypotension after spinal anesthesia in patients undergoing lower segment caesarean section: A prospective, randomized, double-blinded study

Background: Spinal anesthesia (SA) has many advantages in lower segment caesarean section (LSCS), but hypotension is the main issue that can be managed in different ways. This study was conducted to know the effectiveness of three intravenous serotonin receptor antagonists (ramosetron, ondansetron, and granisetron) in the prevention of bradycardia and hypotension during LSCS under SA. Patients and Methods: A total of 160 parturients posted for LSCS under SA were enrolled in this study and divided equally into four groups. Five minutes before SA, Group R received intravenous (IV) 0.3 mg ramosetron, Group O received 4 mg ondansetron IV, Group G received 1 mg granisetron IV, and Group S received IV normal saline. All solutions were diluted with normal saline to 5 mL to blind the drugs. Heart rate (HR), systolic and diastolic blood pressure, and mean arterial pressure were recorded. The total consumption of vasopressor and side effects were recorded. Results: The decrease in mean arterial pressure and mean HR was significantly lower in group R than other groups at all intervals (P < 0.05). The incidence of hypotension was 25% in group R compared with 42.5%, 55%, and 72.5% in groups O, G, and S, respectively. Conclusion: Premedication with intravenous ramosetron significantly reduced hypotension, HR, and total vasopressor usage in LSCS parturients. Intravenous ondansetron and granisetron had lesser effects than ramosetron.