Sepsis can influence blood volume, its distribution, vascular tone, and cardiac function. Persistent hypotension or the need for vasopressors after volume resuscitation is part of the definition of septic shock. Since increased positive fluid balance has been associated with increased morbidity and mortality in sepsis, timing of vasopressors in the treatment of septic shock seems crucial. However, conclusive evidence on timing and sequence of interventions with the goal to restore tissue perfusion is lacking. The aim of this narrative review is to depict the pathophysiology of hypotension in sepsis, evaluate how common interventions to treat hypotension interfere with physiology, and to give a resume of the results from clinical studies focusing on targets and timing of vasopressor in sepsis. The majority of studies comparing early versus late administration of vasopressors in septic shock are rather small, single-center, and retrospective. The range of “early” is between 1 and 12 hours. The available studies suggest a mean arterial pressure of 60 to 65 mm Hg as a threshold for increased risk of morbidity and mortality, whereas higher blood pressure targets do not seem to add further benefits. The data, albeit mostly from observational studies, speak for combining vasopressors with fluids rather “early” in the treatment of septic shock (within a 0–3-hour window). Nevertheless, the optimal resuscitation strategy should take into account the source of infection, the pathophysiology, the time and clinical course preceding the diagnosis of sepsis, and also comorbidities and sepsis-induced organ dysfunction.

脓毒症可影响血容量、分布、血管张力和心脏功能。持续性低血压或容量复苏后需要血管升压药是感染性休克定义的一部分。由于增加的正液体平衡与脓毒症的发病率和死亡率增加有关，因此血管加压药治疗脓毒性休克的时机似乎至关重要。然而，缺乏以恢复组织灌注为目标的干预时间和顺序的确凿证据。这篇叙述性综述的目的是描述脓毒症中低血压的病理生理学，评估治疗低血压的常见干预措施如何干扰生理学，并概述临床研究的结果，重点是脓毒症中血管加压药的目标和时机。大多数比较感染性休克早期和晚期使用血管升压药的研究都是相当小的、单中心的和回顾性的。“早”的范围在 1 到 12 小时之间。现有研究表明，平均动脉压 60 至 65 mm Hg 是增加发病率和死亡率风险的阈值，而更高的血压目标似乎不会增加更多益处。这些数据虽然主要来自观察性研究，但表明在治疗感染性休克时（在 0-3 小时窗口内）相当“早期”将血管加压药与液体结合使用。然而，最佳复苏策略应考虑感染源、病理生理学、脓毒症诊断前的时间和临床过程，以及合并症和脓毒症引起的器官功能障碍。