Weill Cornell Medical College, New York, NY, USA.
Department of Anaesthesiology and Critical Care Medicine, Memorial Sloan Kettering Cancer Centre, New York, NY, USA.
Anaesthesia. 2020 May;75(5):634-641. doi: 10.1111/anae.14984. Epub 2020 Feb 6.
Intra-operative hypotension is a known predictor of adverse events and poor outcomes following major surgery. Hypotension often occurs on induction of anaesthesia, typically attributed to hypovolaemia and the haemodynamic effects of anaesthetic agents. We assessed the efficacy of fluid optimisation for reducing the incidence of hypotension on induction of anaesthesia. This prospective trial enrolled 283 patients undergoing radical cystectomy and randomly allocated them to goal-directed fluid therapy (n = 142) or standard fluid therapy (n = 141). Goal-directed fluid therapy patients received fluid optimisation based on stroke volume response to passive leg raise before induction; those with positive passive leg raise received intravenous crystalloid fluid boluses until stroke volume was optimised. Baseline mean arterial pressure was measured on the morning of surgery and on arriving in the operating theatre. This post-hoc analysis defined haemodynamic instability as either a > 30% relative drop in mean arterial pressure compared with baseline or absolute mean arterial pressure < 55 mmHg, within 15 min of induction. Forty-two (30%) goal-directed fluid therapy patients underwent fluid optimisation after finding an intravascular fluid deficit via passive leg raise testing; 106 (75%) goal-directed fluid therapy and 112 (79%) standard fluid therapy patients met criteria for haemodynamic instability. There was no significant difference in the incidence of haemodynamic instability between the goal-directed fluid therapy and standard fluid therapy groups using absolute mean arterial pressure drop below 55 mmHg (p = 0.58) or using pre-surgical testing or pre-surgical mean arterial pressure values as baseline (p = 0.21, p = 0.89, respectively); however, the difference in the incidence of haemodynamic instability was significant using the operating theatre baseline mean arterial pressure (p = 0.004). We conclude that fluid optimisation before induction of general anaesthesia did not significantly impact haemodynamic instability.
术中低血压是重大手术后不良事件和不良结局的已知预测因素。低血压通常发生在麻醉诱导时，通常归因于血容量不足和麻醉药物的血液动力学效应。我们评估了液体优化以减少麻醉诱导时低血压发生率的效果。这项前瞻性试验纳入了 283 例接受根治性膀胱切除术的患者，并将他们随机分配到目标导向液体治疗组（n=142）或标准液体治疗组（n=141）。目标导向液体治疗组患者在麻醉诱导前根据被动抬腿试验中每搏量的反应接受液体优化；对被动抬腿试验阳性的患者给予静脉晶体液冲击，直到优化每搏量。手术当天早上和到达手术室时测量基础平均动脉压。本事后分析将血流动力学不稳定定义为与基础值相比平均动脉压相对下降>30%或诱导后 15 分钟内平均动脉压绝对值<55mmHg。通过被动抬腿试验发现血管内液体不足后，42 例（30%）目标导向液体治疗患者接受了液体优化；106 例（75%）目标导向液体治疗和 112 例（79%）标准液体治疗患者符合血流动力学不稳定的标准。使用绝对平均动脉压下降<55mmHg（p=0.58）或使用术前测试或术前平均动脉压值作为基础值（p=0.21，p=0.89）时，目标导向液体治疗组和标准液体治疗组血流动力学不稳定的发生率没有显著差异；然而，使用手术室基础平均动脉压时，血流动力学不稳定的发生率差异显著（p=0.004）。我们的结论是，在全身麻醉诱导前进行液体优化并没有显著影响血流动力学不稳定。
