Department of Anaesthesiology, Institute of Post Graduate Medical Education & Research, Kolkata, India.
Int J Obstet Anesth. 2012 Jan;21(1):24-8. doi: 10.1016/j.ijoa.2011.08.002. Epub 2011 Nov 18.
Subarachnoid block is the preferred method of anaesthesia for caesarean section, but is associated with hypotension and bradycardia, which may be deleterious to both parturient and baby. Animal studies suggest that in the presence of decreased blood volume, 5-HT may be an important factor inducing the Bezold Jarisch reflex via 5-HT3 receptors located in intracardiac vagal nerve endings. In this study, we evaluated the effect of ondansetron, as a 5-HT3 receptor antagonist, on the haemodynamic response following subarachnoid block in parturients undergoing elective caesarean section.
Fifty-two parturients scheduled for elective caesarean section were randomly allocated into two groups. Before induction of spinal anaesthesia Group O (n=26) received intravenous ondansetron 4 mg; Group S (n=26) received normal saline. Blood pressure, heart rate and vasopressor requirements were assessed.
Decreases in mean arterial pressure were significantly lower in Group O than Group S from 14 min until 35 min. Patients in Group O required significantly less vasopressor (P=0.009) and had significantly lower incidences of nausea and vomiting (P=0.049).
Ondansetron 4 mg, given intravenously 5 min before subarachnoid block reduced hypotension and vasopressor use in parturients undergoing elective caesarean section.
蛛网膜下腔阻滞是剖宫产术首选的麻醉方法，但与低血压和心动过缓有关，这可能对产妇和婴儿都有害。动物研究表明，在血容量减少的情况下，5-HT 可能通过位于心脏迷走神经末梢的 5-HT3 受体成为诱发 Bezold-Jarisch 反射的重要因素。在这项研究中，我们评估了昂丹司琼（一种 5-HT3 受体拮抗剂）对择期剖宫产产妇蛛网膜下腔阻滞后血液动力学反应的影响。
52 例拟行择期剖宫产的产妇随机分为两组。在脊髓麻醉诱导前，O 组（n=26）静脉注射昂丹司琼 4mg；S 组（n=26）给予生理盐水。评估血压、心率和血管加压药的需求。
与 S 组相比，O 组从 14 分钟到 35 分钟的平均动脉压下降明显较低。O 组患者需要的血管加压药明显较少（P=0.009），恶心和呕吐的发生率明显较低（P=0.049）。
蛛网膜下腔阻滞前 5 分钟静脉注射昂丹司琼 4mg 可减少择期剖宫产产妇的低血压和血管加压药的使用。
