Ferré Fabrice, Martin Charlotte, Bosch Laetitia, Kurrek Matt, Lairez Olivier, Minville Vincent
Department of Anesthesia and Intensive Care Medicine, CHU Purpan, Toulouse, France.
Department of Anesthesia, University of Toronto, Toronto, ON M5S 3E2, Canada.
Local Reg Anesth. 2020 Jun 3;13:39-46. doi: 10.2147/LRA.S240753. eCollection 2020.
Spinal anesthesia-induced hypotension (SAIH) occurs frequently, particularly in the elderly and in patients undergoing caesarean section. SAIH is caused by arterial and venous vasodilatation resulting from the sympathetic block along with a paradoxical activation of cardioinhibitory receptors. Bradycardia after spinal anesthesia (SA) must always be treated as a warning sign of an important hemodynamic compromise. Fluid preloading (before initiation of the SA) with colloids such as hydroxyethyl starch (HES) effectively reduces the incidence and severity of arterial hypotension, whereas crystalloid preloading is not indicated. Co-loading with crystalloid or colloid is as equally effective to HES preloading, provided that the speed of administration is adequate (ie, bolus over 5 to 10 minutes). Ephedrine has traditionally been considered the vasoconstrictor of choice, especially for use during SAIH associated with bradycardia. Phenylephrine, a α adrenergic receptor agonist, is increasingly used to treat SAIH and its prophylactic administration (ie, immediately after intrathecal injection of local anesthetics) has been shown to decrease the incidence of arterial hypotension. The role of norepinephrine as a possible alternative to phenylephrine seems promising. Other drugs, such as serotonin receptor antagonists (ondansetron), have been shown to limit the blood pressure drop after SA by inhibiting the Bezold-Jarisch reflex (BJR), but further studies are needed before their widespread use can be recommended.
脊髓麻醉诱导的低血压（SAIH）很常见，尤其是在老年人和接受剖宫产的患者中。SAIH是由交感神经阻滞导致的动静脉血管扩张以及心脏抑制性受体的反常激活引起的。脊髓麻醉（SA）后的心动过缓必须始终被视为重要血流动力学损害的警示信号。术前使用胶体溶液如羟乙基淀粉（HES）进行液体预负荷（在SA开始前）可有效降低动脉低血压的发生率和严重程度，而晶体液预负荷则不适用。与晶体液或胶体溶液联合预负荷与HES预负荷同样有效，前提是给药速度足够（即5至10分钟内推注）。传统上，麻黄碱被认为是首选的血管收缩剂，特别是用于与心动过缓相关的SAIH期间。去氧肾上腺素，一种α肾上腺素能受体激动剂，越来越多地用于治疗SAIH，并且其预防性给药（即在鞘内注射局部麻醉剂后立即给药）已被证明可降低动脉低血压的发生率。去甲肾上腺素作为去氧肾上腺素的一种可能替代药物的作用似乎很有前景。其他药物，如5-羟色胺受体拮抗剂（昂丹司琼），已被证明可通过抑制贝佐尔德-雅里什反射（BJR）来限制SA后的血压下降，但在推荐广泛使用之前还需要进一步研究。
