Department of Pharmacy Services, Mayo Clinic, Rochester, MN, United States of America.
Department of Pharmacy Services, Mayo Clinic, Rochester, MN, United States of America.
Am J Emerg Med. 2023 Aug;70:133-139. doi: 10.1016/j.ajem.2023.05.026. Epub 2023 May 26.
Acute pain accounts for over 70% of Emergency Department (ED) visits. Sub-dissociative dose ketamine (0.1-0.6 mg/kg) is safe and effective for the management of acute pain in the ED. However, the optimal dose of intravenous ketamine that provides effective analgesia and minimizes the risk of adverse effects has yet to be identified. The objective of this study was to describe an effective analgesia dose range of IV ketamine for acute pain in the ED.
This multi-center, retrospective cohort study evaluated adult patients who received analgesic and sub-dissociative dose ketamine for the management of acute pain between May 5, 2018, and August 30, 2021, in 21 emergency departments at academic, community, and critical access hospitals across four states. Patients were excluded if they received ketamine for an indication other than pain, such as procedural sedation or intubation, or for whom there was incomplete documentation for the primary outcome. Patients who received a ketamine dose <0.3 mg/kg were stratified into the low-dose group, and those who received a dose of 0.3 mg/kg or higher to the high-dose group. The primary outcome was change in pain scores within 60 min using a standard 11-point numeric rating scale (NRS). Secondary outcomes included incidence of adverse effects and use of rescue analgesics. Continuous variables were compared between dose groups using student t-test or Wilcoxon Rank-Sum test. Linear regression was used to assess the association between the change in NRS pain scores within 60 min and dose after adjusting for baseline pain, requiring an additional dose of ketamine, and receiving an opioid.
From 3796 patient encounters screened for receipt of ketamine, 384 patients met inclusion criteria including 258 in the low-dose group, and 126 in the high-dose group. The primary reason for exclusion was incomplete documentation of pain scores, or ketamine used for sedation. Median baseline pain scores were 8.2 in the low-dose group and 7.8 in the high-dose group (difference 0.5; 95% CI 0 to 1, p = 0.04). Both groups demonstrated significant reductions in their mean NRS pain scores within 60 min following the first administration of IV ketamine. There were no differences in the change in pain scores between both groups (-2.2 vs -2.6, mean difference 0.4, 95% CI -0.4 to 1.1, p = 0.34). Use of rescue analgesics (40.7% vs 36.5%, p = 0.43) and adverse effects were similar between groups, including early discontinuation of the ketamine infusion (37.2% vs. 37.3%, p = 0.99). Overall, the most common adverse effects were agitation (7.3%) and nausea (7.0%).
The analgesic efficacy and safety of high-dose sub-dissociative ketamine (≥0.3 mg/kg) was not superior to low-dose (< 0.3 mg/kg) for the management of acute pain in the ED. Low-dose ketamine <0.3 mg/kg is an effective and safe pain management strategy in this population.
急性疼痛占急诊科（ED）就诊的 70%以上。亚分离剂量氯胺酮（0.1-0.6mg/kg）可安全有效地用于治疗 ED 中的急性疼痛。然而，提供有效镇痛作用且最小化不良反应风险的最佳静脉内氯胺酮剂量尚未确定。本研究的目的是描述亚分离剂量氯胺酮在 ED 急性疼痛中的有效镇痛剂量范围。
这是一项多中心回顾性队列研究，评估了 2018 年 5 月 5 日至 2021 年 8 月 30 日期间在四个州的 21 家学术、社区和关键通道医院的急诊科接受镇痛和亚分离剂量氯胺酮治疗的成年患者。如果患者因疼痛以外的其他指征接受氯胺酮治疗，例如程序镇静或插管，或者主要结局的记录不完整，则将其排除在外。接受剂量 <0.3mg/kg 氯胺酮的患者分为低剂量组，接受剂量为 0.3mg/kg 或更高剂量的患者分为高剂量组。主要结局是使用标准 11 点数字评分量表（NRS）在 60min 内疼痛评分的变化。次要结局包括不良反应的发生率和使用解救性镇痛药。使用学生 t 检验或 Wilcoxon 秩和检验比较剂量组之间的连续变量。使用线性回归评估 60min 内 NRS 疼痛评分变化与剂量之间的关联，同时调整基线疼痛、需要额外剂量的氯胺酮和使用阿片类药物。
在筛查接受氯胺酮治疗的 3796 例患者中，有 384 例符合纳入标准，包括低剂量组 258 例，高剂量组 126 例。排除的主要原因是疼痛评分记录不完整，或氯胺酮用于镇静。低剂量组和高剂量组的中位基线疼痛评分分别为 8.2 和 7.8（差异 0.5；95%CI 0 至 1，p=0.04）。两组患者在首次静脉内给予氯胺酮后 60min 内的平均 NRS 疼痛评分均显著降低。两组之间疼痛评分的变化没有差异（-2.2 与-2.6，平均差异 0.4，95%CI -0.4 至 1.1，p=0.34）。解救性镇痛药的使用（40.7% 与 36.5%，p=0.43）和不良反应在两组之间相似，包括氯胺酮输注早期停止（37.2% 与 37.3%，p=0.99）。总体而言，最常见的不良反应是激越（7.3%）和恶心（7.0%）。
高剂量亚分离氯胺酮（≥0.3mg/kg）的镇痛效果和安全性并不优于低剂量（<0.3mg/kg），用于治疗 ED 中的急性疼痛。低剂量（<0.3mg/kg）氯胺酮是该人群中有效且安全的疼痛管理策略。
