Abstract :
Introduction: Hypotension is most common intraoperative complication after spinal anesthesia during
cesarean delivery. The Bezold–Jarisch reflex is one of the causes for occurrence of hypotension after spinal
anesthesia through serotonin with decreased blood volume. Our aim of this study was to compare the two
serotonin receptor antagonists Ondansetron and Granisetron to prevent spinal induced hypotension and
bradycardia after spinal anesthesia in parturients undergoing cesarean sections.
Materials and Methods: 90 patients of ASA class-I and II, aged 20-40years, weight 40-80kilograms were
included in this study. Patient with history of PIH, convulsion, any major comorbidity were excluded from
study. Patients were assigned into 3 groups group A received 4 mg Ondansetron intravenously, group B
received 1 mg Granisetron intravenously and group C received 10 ml of intravenous normal saline 5 min
before spinal anaesthesia. The difference in mean was analyzed using post hoc Bonferroni test and ANOVA
test. The difference in proportions was analyzed by using chi-square test.
Results: SBP, DBP and MBP were statistically lower in both Granisetron and Saline group as compared to
Ondansetron group at most of the times after drug administration. Heart rate and shivering were comparable
in the three groups. Nausea and vomiting was statistically more in saline group as compared to other groups.
Use of ephedrine was also significantly more in saline group (37%).
Conclusion: 4mg intravenous Ondansetron prior to spinal anaesthesia in LSCS patients reduces
the incidence of hypotension, bradycardia and need of vasopressor. Granisetron had no effect on
haemodynamic parameters.
Keyword :
Hypotensiòn, Ondensetron, Granisetron, Bezold jarisch reflex, Spinal anesthesia, Bupivacaine.