Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA.
Department of Critical Care, King's College London, Guy's and St Thomas' National Health Service Foundation Hospital, London, United Kingdom.
Semin Nephrol. 2019 Sep;39(5):462-472. doi: 10.1016/j.semnephrol.2019.06.006.
Acute kidney injury (AKI) is common in the setting of shock. Hemodynamic instability is a risk factor for the development of AKI, and pathophysiological mechanisms include loss of renal perfusion pressure and impaired microcirculation. Although restoration of mean arterial pressure (MAP) may mitigate the risk of AKI to some extent, evidence on this is conflicting. Also debatable is the optimal blood pressure needed to minimize the risk of kidney injury. A MAP of 65 mm Hg traditionally has been considered adequate to maintain renal perfusion pressure, and studies have failed to consistently show improved outcomes at higher levels of MAP. Therapeutic options to support renal perfusion consist of catecholamines, vasopressin, and angiotensin II. Although catecholamines are the most studied, they are associated with adverse events at higher doses, including AKI. Vasopressin and angiotensin II are noncatecholamine options to support blood pressure and may improve microcirculatory hemodynamics through unique mechanisms, including differential vasoconstriction of efferent and afferent arterioles within the nephron. Future areas of study include methods by which clinicians can measure renal blood flow in a macrocirculatory and microcirculatory way, a personalized approach to blood pressure management in septic shock using patient-specific measures of perfusion adequacy, and novel agents that may improve the microcirculation within the kidneys without causing adverse microcirculatory effects in other organs.
急性肾损伤(AKI)在休克中很常见。血流动力学不稳定是 AKI 发展的危险因素,其病理生理机制包括肾灌注压丧失和微循环受损。尽管平均动脉压(MAP)的恢复在一定程度上可能减轻 AKI 的风险,但这方面的证据存在矛盾。需要最低限度降低肾损伤风险的最佳血压也存在争议。传统上,65mmHg 的 MAP 被认为足以维持肾灌注压,而研究未能一致表明更高水平的 MAP 会带来改善的结果。支持肾灌注的治疗选择包括儿茶酚胺、血管加压素和血管紧张素 II。尽管儿茶酚胺是研究最多的,但它们在较高剂量下与不良事件相关,包括 AKI。血管加压素和血管紧张素 II 是支持血压的非儿茶酚胺选择,它们可能通过独特的机制改善微循环血液动力学,包括在肾单位内对出球小动脉和入球小动脉的差异化血管收缩。未来的研究领域包括临床医生可以用宏观循环和微循环的方法测量肾血流量的方法、使用灌注充足的患者特定措施对脓毒性休克进行血压管理的个性化方法,以及可能改善肾脏微循环而不会在其他器官引起不良微循环影响的新型药物。