Effect of ondansetron on post-dural puncture headache (PDPH) in parturients undergoing cesarean section: a double-blind randomized placebo-controlled study

One of the most exhausting complications of spinal anesthesia, especially in parturients, is post-dural puncture headache (PDPH). This headache is not responsive to the usual pain killers. Ondansetron is a 5-HT3 receptor antagonist which is generally used for the prophylactic management of nausea and vomiting; however, studies have found that ondansetron might decrease the incidence of PDPH. Therefore, we aimed to evalute the effect of ondansetron on decreasing the incidence of PDPH. In this double-blind randomized placebo-controlled clinical trial, 210 parturients who underwent elective cesarean section under spinal anesthesia were randomly allocated to two groups. The intervention group received 0.15 mg/kg ondansetron, while the control group received 5 ml normal saline. Heart rate and mean arterial pressure (MAP) were recorded during surgery. Furthermore, postoperative nausea and vomiting (PONV) and PDPH in the two groups were noted by an anesthetic nurse for 3 days and compared. The incidence of PDPH in the intervention group was significantly lower than in the control group (P = 0.001). The incidence of PONV was also significantly lower in the intervention group compared to the control group (P < 0.05). However, MAP was significantly higher in the intervention group compared to the control group (P < 0.05). No significant difference was found between the two groups regarding heart rate (P > 0.05). Ondansetron (0.15 mg/kg) appeared to reduce the incidence of PDPH, as well as the incidence of hypotension and PONV, in parturients undergoing spinal anesthesia for cesarean section.