Department of Emergency Medicine, Albert Einstein College of Medicine, Bronx, NY, USA.
Acad Emerg Med. 2012 Apr;19(4):370-7. doi: 10.1111/j.1553-2712.2012.01322.x.
The objective was to assess the efficacy of patient-controlled analgesia (PCA) in the emergency department (ED) and to compare two PCA dosing regimens.
A randomized controlled trial with three treatment arms was performed in an urban ED. A convenience sample of ED patients ages 18 to 65 years with abdominal pain of 7 days or less duration requiring intravenous (IV) opioid analgesia was enrolled between April 2009 and June 2010. All patients received an initial dose of 0.1 mg/kg IV morphine followed by physician-managed analgesia as needed. Patients in the PCA arms also received IV morphine with on-demand doses of 1 or 1.5 mg, with a 6-minute lockout between doses. Pain intensity was rated by patients on an 11-point numeric rating scale (NRS). Satisfaction with pain treatment, desire for the same treatment in the future, and need for additional analgesia were assessed at study end. Adverse events (O(2) sat < 92%, respiratory rate [RR] < 10/min, systolic blood pressure [sBP] < 90 mm Hg, and naloxone use) were counted. One-way analysis of variance was used to test the difference among groups in short-term pain relief, as assessed by mean change in NRS pain intensity from baseline to 30 minutes and pain over the entire 2-hour study period measured by area under the curve (AUC) of NRS pain ratings. A post hoc hierarchical linear model was used to test the observed difference in NRS between the groups between 30 and 120 minutes.
A total of 211 patients were enrolled. A sharp, nearly identical decline in mean NRS scores occurred from baseline to 30 minutes in the three groups (p = 0.82). Between 30 and 120 minutes, there was little further decline in the non-PCA NRS scores, while both PCA groups continued to decline (p = 0.004). The net treatment effect over the entire 2 hours was smallest in the non-PCA group and largest in the group receiving 1.5 mg of morphine (p = 0.06). The mean decline in pain from baseline to 120 minutes postbaseline in both PCA groups was 1.4 NRS units (95% confidence interval [CI] = 0.3 to 2.4) greater than the decline in patients treated without PCA. More patients in the PCA arms reported satisfaction, wanting the same pain management in the future, and not wanting further analgesics at 120 minutes than patients who did not receive PCA. There were no clinically or statistically significant differences in any outcomes between the two PCA groups. One PCA patient had a transient oxygen saturation of 88% after the initial bolus only, and one non-PCA patient had a brief drop in sBP to 87 mm Hg.
This study provides support for efficacy of PCA when applied to the ED setting. Future studies designed to assess implementation of this modality in the context of conditions of actual ED staffing and competing patient demands are warranted.
评估患者自控镇痛（PCA）在急诊科（ED）的疗效，并比较两种 PCA 给药方案。
这是一项在城市 ED 中进行的随机对照试验，设有三个治疗组。2009 年 4 月至 2010 年 6 月期间，纳入了年龄在 18 至 65 岁之间、腹痛持续时间为 7 天或更短、需要静脉（IV）阿片类药物镇痛的 ED 患者。所有患者均接受 0.1 mg/kg IV 吗啡初始剂量，随后根据需要进行医生管理的镇痛。PCA 组的患者还接受 IV 吗啡按需给予 1 或 1.5 mg，剂量之间有 6 分钟的锁定时间。疼痛强度由患者在 11 点数字评分量表（NRS）上进行评分。在研究结束时评估对疼痛治疗的满意度、未来是否希望接受相同的治疗以及是否需要额外的镇痛。计算不良事件（O(2)sat < 92%、RR < 10/min、sBP < 90 mmHg 和使用纳洛酮）。采用单因素方差分析比较三组患者在短期疼痛缓解方面的差异，通过 NRS 疼痛强度从基线到 30 分钟的平均变化和整个 2 小时研究期间 NRS 疼痛评分的曲线下面积（AUC）来衡量疼痛程度。采用事后分层线性模型来检验组间在 30 至 120 分钟之间 NRS 观察到的差异。
共纳入 211 名患者。三组患者的 NRS 评分从基线到 30 分钟均呈明显、几乎相同的下降趋势（p = 0.82）。在 30 至 120 分钟之间，非 PCA NRS 评分的下降幅度较小，而两个 PCA 组仍在继续下降（p = 0.004）。整个 2 小时的净治疗效果在非 PCA 组最小，在接受 1.5 mg 吗啡的组最大（p = 0.06）。在基线后 120 分钟，两个 PCA 组的疼痛从基线到基线的平均下降幅度比未接受 PCA 治疗的患者高 1.4 NRS 单位（95%置信区间 [CI] = 0.3 至 2.4）。在 120 分钟时，PCA 组的患者报告满意度、未来希望接受相同的疼痛管理以及不再需要额外镇痛的比例均高于未接受 PCA 治疗的患者。两组 PCA 患者之间在任何结局方面均无临床或统计学上的显著差异。只有 1 名 PCA 患者在初始推注后仅出现短暂的氧饱和度为 88%，1 名非 PCA 患者的收缩压短暂下降至 87 mmHg。
本研究支持在 ED 环境中应用 PCA 的疗效。需要进一步研究设计以评估在实际 ED 人员配备和竞争患者需求的情况下实施这种模式的情况。
