1 Department of Pharmacy, Massachusetts General Hospital, Boston, MA, USA.
2 Division of Trauma, Emergency Surgery and Surgical Critical Care, Massachusetts General Hospital, Boston, MA, USA.
J Intensive Care Med. 2019 Aug;34(8):646-651. doi: 10.1177/0885066617706907. Epub 2017 May 3.
Ketamine at subanesthetic doses has been shown to provide analgesic effects without causing respiratory depression and may be a viable option in mechanically ventilated patients to assist with extubation. The aim of this study was to evaluate the effects of low-dose ketamine on opioid consumption in mechanically ventilated adult surgical intensive care unit (ICU) patients.
A retrospective review of mechanically ventilated adult patients receiving low-dose ketamine continuous infusion (1-5 µcg/kg/min) for adjunctive pain control admitted to surgical ICUs was conducted. Patients were included if they met an ICU safety screen for a spontaneous breathing trial (SBT) implying extubation readiness pending SBT results. The primary end point was the slope of change in morphine equivalents (MEs) 12 hours pre- and postketamine infusion. We hypothesized that low-dose ketamine would increase the slope of opioid dose reduction.
Forty patients were analyzed. The median dose of ketamine was 5 µg/kg/min (interquartile range [IQR]: 3.5-5) and the treatment duration was 1.89 days (IQR: 0.96-3.06). Prior to ketamine, the majority of patients received volume-controlled or pressure-supported ventilation with a median duration of 2.05 days (IQR: 1.38-3.61). The median time from the initiation of ketamine to extubation was 1.44 days (IQR: 0.58-2.66). For the primary outcome, there was a significant difference in the slope of ME changes from 1 to -0.265 mg/h 12 hours pre- and postketamine initiation ( < .001). For the secondary outcomes, ketamine was associated with a decrease in vasopressor requirements (phenylephrine equivalent 70 vs 40 mg/h; = .019).
Low-dose continuous infusion ketamine in mechanically ventilated adult patients was associated with a significant increase in the rate of opioid dose reduction without adverse effects on hemodynamic stability.
亚麻醉剂量的氯胺酮已被证明具有镇痛作用而不会引起呼吸抑制，并且在机械通气患者中可能是一种可行的选择，以协助拔管。本研究旨在评估小剂量氯胺酮对机械通气成人外科重症监护病房（ICU）患者阿片类药物消耗的影响。
对接受小剂量氯胺酮持续输注（1-5μg/kg/min）辅助镇痛的机械通气成人患者进行回顾性审查，这些患者被收入外科 ICU 并接受了 ICU 安全筛查以进行自主呼吸试验（SBT），这意味着等待 SBT 结果以准备拔管。主要终点是氯胺酮输注前 12 小时和输注后吗啡等效物（ME）变化的斜率。我们假设小剂量氯胺酮会增加阿片类药物剂量减少的斜率。
分析了 40 名患者。氯胺酮的中位数剂量为 5μg/kg/min（四分位距[IQR]：3.5-5），治疗持续时间为 1.89 天（IQR：0.96-3.06）。在氯胺酮之前，大多数患者接受容量控制或压力支持通气，中位数持续时间为 2.05 天（IQR：1.38-3.61）。从开始使用氯胺酮到拔管的中位数时间为 1.44 天（IQR：0.58-2.66）。对于主要结局，氯胺酮开始前 12 小时和开始后吗啡等效物变化斜率有显著差异，从 1 到 -0.265mg/h（<0.001）。对于次要结局，氯胺酮与降低血管加压药需求相关（去甲肾上腺素等效物 70 与 40mg/h；=0.019）。
机械通气的成年患者中，小剂量持续输注氯胺酮与阿片类药物剂量减少率显著增加相关，而对血流动力学稳定性无不良影响。
