Effects of Ondansetron on Hemodynamic Changes After Spinal Anesthesia in Geriatric Urologic Surgery

Overview

Spinal anesthesia is frequently used in urologic surgery in geriatric patients; however, it may cause significant hemodynamic changes such as hypotension and bradycardia. These changes can be more pronounced in elderly patients due to age-related physiological alterations. Ondansetron, a 5-HT3 receptor antagonist commonly used for the prevention of postoperative nausea and vomiting, has been suggested to attenuate spinal anesthesia-induced hemodynamic instability by modulating vagal reflexes. This prospective observational study aimed to evaluate the effects of ondansetron on hemodynamic changes following spinal anesthesia in geriatric patients undergoing urologic surgery. Hemodynamic parameters were recorded during the intraoperative period, and the incidence of hypotension, bradycardia, and vasopressor requirements were assessed.

This study was designed as a prospective observational study conducted in geriatric patients undergoing urologic surgery under spinal anesthesia. Patient enrollment and data collection were performed prospectively between December 18, 2024, and April 18, 2025. The study protocol was approved by the TABED Ethics Committee (Approval No: 1-24-840, December 18, 2024). Ondansetron was administered according to routine clinical practice. Hemodynamic parameters, including mean arterial pressure and heart rate, were recorded at predefined time points following spinal anesthesia. The incidence of spinal anesthesia-induced hypotension, bradycardia, and the need for vasopressor support were evaluated. Although patient enrollment and data collection were conducted prospectively, the study was registered retrospectively at ClinicalTrials.gov due to delayed trial registration.

Conditions