Comparative Study between Intramuscular Ephedrine Versus Intravenous Ondansetron Versus Intravenous Dexamethasone for Prevention of Spinal Anaesthesia-Induced Hypotension in Parturients Undergoing Caesarean Section

Abstract Background: Hypotension is one of the most common intra-operative complications associated with spinal anaesthe-sia. Its incidence in caesarean section has been estimated to be as high as 50-60%. The cardinal symptoms of hypotension include light headedness or dizziness. If the blood pressure is markedly low, loss of consciousness and seizures may occur. Several studies suggest that hypotension during spinal anaesthesia may causes everal adverseevents such as delirium and coronary ischemia. In spite of using a lot of prophylactic measures as left displacement of the pregnant uterus, Admin-istration of pre-load or co-load of crystalloid and colloid solutions and use of vasopressors, none of them can totally avoid maternal hypotension post-spinal anaesthesia. Aim of Study: The aim of the study was to compare efficacy and safety of Ephedrine versus Ondansetron versus Dexamethasone inpreventing spinal anaesthesia-induced hypotension in parturients undergoing caesarean section. Patients and Methods: This study was a comparative randomized double-blind trial applied on 153 patients divided into three Groups, Group I (n=52): Received 25mg ephedrine (1ml) IM and 5ml saline (IV), 25 minutes before spinal anaesethia; Group II (n=50): Received 4mg ondansetron in 5ml normal saline (IV), and 1ml saline IM, 25 minutes before spinal anesthesia, and Group III (n=51): Received 4mg dex-amethasone in 5ml normal saline (IV) and 1ml saline IM, 25 minutes before spinal anesthesia. All cases were collected from anesthesia Department at Bab El Shearia university Hospital, Al-Azhar University during the period from April 2019 to April 2021. Results: There is statistically significant difference in degree of hypotension between the studied groups, hypotension in Ephedrine group was in 20 cases (38.5%), followed by Dexamethasone group 14 cases (27.5%), while the Ondansetron group was in 8 cases (16%). By looking at the dose of vaso-constrictors, vomiting, nausea and shivering, the results showed no statistically significant differences.
Conclusion: The preemptive use of Ephedrine, Ondanset-ron and Dexamethasone in reducingpost-spinal hypotension (PSH) in obstetric patients undergoing cesarian sectionshowed thatthe Ondansetron drug was more effective in reducing post-spinal hypotension than Dexamethasone followed by Ephedrine.