Journal of Advances in Medical and Biomedical Research

en The Effect of Intravenous Ondansetron on Prevention of Hemodynamic Instability in Patients Undergoing Elective Caesarean Surgery: A Double-Blind Randomized Clinical Trial Clinical Medicine Clinical Medicine کارآزمایی بالینی Clinical Trials Background & Objective: Spinal anesthesia for elective cesarean delivery has a high incidence of hypotension (50-80%) caused by sympathetic inhibition and activation of the Bezold-Jarisch reflex. This double-blind randomized study was designed to determine whether preoperative administration of 4 mg of intravenous Ondansetron can stabilize hemodynamics in patients undergoing elective cesarean section.  Materials & Methods:  Sixty ASA I pregnant women scheduled for elective cesarean delivery were randomized to receive IV Ondansetron (n=30) or placebo (n=30) 3 minutes before spinal anesthesia (12.5 mg hyperbaric bupivacaine + 2.5 µg sufentanil). Hemodynamic parameters (heart rate and blood pressure trends) were primary outcomes; secondary outcomes included ephedrine requirements and adverse events. Independent t-tests, ANOVA, Mann-Whitney U tests, and Chi-square tests (SPSS v22; α = 0.05) were used in the statistical analysis. Results:  Ondansetron was associated with significantly more shivering (46.7% vs. 17.2%; P<0.05). The Ondansetron group maintained a higher total heart rate (93.50 ± 1.742 vs. 88.34 ± 1.673 bpm; P=0.044), with significant increases at 25, 45, and 120 minutes (P<0.05). Although diastolic blood pressure/mean arterial pressure was higher at later periods (75/105 min; P<0.05), systolic blood pressure in the Ondansetron group was lower at 5 minutes (108.81 ± 16.072 vs. 118.86 ± 16.072 mmHg, P<0.01). Overall, there were no net differences in blood pressure. The Ondansetron group required ephedrine more frequently (77.4% vs. 58.6%), although they had the same mean dose (14.16±7.019 vs. 12.35±5.036 mg; P=0.368). Ondansetron caused significantly more shivering (46.7% vs. 17.2%; P<0.05). Conclusion:  Prophylactic Ondansetron raises heart rate and momentarily increases late-phase BP but worsens early hypotension and shivering. It offers no overall hemodynamic benefit and may raise vasopressor requirements, so caution is advised in clinical use. Ondansetron, Caesarean Section, Spinal Anesthesia, Hypotension, Bezold-Jarisch Refle 148 155 http://journal.zums.ac.ir/browse.php?a_code=A-10-7134-1&slc_lang=en&sid=1 Kaveh Behaeen drbehaeen-k@ajums.ac.ir 5200319475328460087087 5200319475328460087087 No Department of Anesthesiology, Pain Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Ahmadreza Mohtadi gharbavi1-m@ajums.ac.ir 5200319475328460087088 5200319475328460087088 Yes Department of Anesthesiology, Pain Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Sholeh Nesioonpour nesioonpour-sh@ajums.ac.ir 5200319475328460087089 5200319475328460087089 No Department of Anesthesiology, Pain Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Ali Ghomeishi ghomeishi-a@ajums.ac.ir 5200319475328460087090 5200319475328460087090 No Department of Anesthesiology, Pain Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Maryam Mofrad Boushehri mostafaabdollah516@gmail.com 5200319475328460087091 5200319475328460087091 No Department of Anesthesiology, Pain Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Fatemeh Javaherforooshzadeh javaherforoosh-f@ajums.ac.ir 5200319475328460087092 5200319475328460087092 No Department of Anesthesiology, Pain Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Afaq Mahdi Ali Afaq.mahdi@uoturath.edu.iq 5200319475328460087093 5200319475328460087093 No Faculty of Pharmacy, Al-turath University, Baghdad, Iraq Omar Abdul Jabbar Abdul Qader dromarqader@gmail.com 5200319475328460087094 5200319475328460087094 No College of Dentistry, Al Mashreq University, Baghdad, Iraq Mahmoud Gharbavi gharbavi1981@gmail.com 5200319475328460087095 5200319475328460087095 No Nanotechnology Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran