Caumo Wolnei, Torres Fernanda, Moreira Nívio L, Auzani Jorge A S, Monteiro Cristiano A, Londero Gustavo, Ribeiro Diego F M, Hidalgo Maria Paz L
Anesthesia Service and Perioperative Medicine at Hospital de Clínicas de Porto Alegre (HCPA), Universidade Federal do Rio Grande do Sul (UFRGS), Brazil.
Anesth Analg. 2007 Nov;105(5):1263-71, table of contents. doi: 10.1213/01.ane.0000282834.78456.90.
Melatonin has sedative, analgesic, antiinflammatory, antioxidative, and chronobiotic effects. We determined the impact of oral melatonin premedication on anxiolysis, analgesia, and the potency of the rest/activity circadian rhythm.
This randomized, double-blind, placebo-controlled study included 33 patients, ASA physical status I-II, undergoing abdominal hysterectomy. Patients were randomly assigned to receive either oral melatonin 5 mg (n = 17) or placebo (n = 16) the night before and 1 h before surgery. The analysis instruments were the Visual Analog Scale, the State-Trait Anxiety Inventory, and the actigraphy.
The number of patients that needed to be treated to prevent one additional patient reporting high postoperative anxiety and moderate to intense pain in the first 24 postoperative hours was 2.53 (95% CI, 1.41-12.22) and 2.20 (95% CI, 1.26-8.58), respectively. The number-needed-to-treat was 3 (95% CI, 1.35-5.0) to prevent high postoperative anxiety in patients with moderate to intense pain, when compared with 7.5 (95% CI, 1.36-infinity) in the absence of pain or mild pain. Also, the treated patients required less morphine by patient-controlled analgesia, as assessed by repeated measures ANOVA (F[1,31] = 6.05, P = 0.02). The rest/activity cycle, assessed by actigraphy, showed that the rhythmicity percentual of 24 h was higher in the intervention group in the first week after discharge ([21.16 +/- 8.90] versus placebo [14.00 +/- 7.10]; [t = -2.41, P = 0.02]).
This finding suggested that preoperative melatonin produced clinically relevant anxiolytic and analgesic effects, especially in the first 24 postoperative hours. Also, it improved the recovery of the potency of the rest/activity circadian rhythm.
褪黑素具有镇静、镇痛、抗炎、抗氧化和调节生物钟的作用。我们确定了口服褪黑素预处理对焦虑缓解、镇痛以及静息/活动昼夜节律强度的影响。
这项随机、双盲、安慰剂对照研究纳入了33例美国麻醉医师协会（ASA）身体状况为I-II级、接受腹部子宫切除术的患者。患者被随机分配在手术前一晚及术前1小时口服5毫克褪黑素（n = 17）或安慰剂（n = 16）。分析工具包括视觉模拟量表、状态-特质焦虑量表和活动记录仪。
为防止再有一名患者在术后24小时内报告高度术后焦虑和中度至重度疼痛，所需治疗的患者数量分别为2.53（95%置信区间，1.41 - 12.22）和2.20（95%置信区间，1.26 - 8.58）。与无疼痛或轻度疼痛患者所需治疗人数7.5（95%置信区间，1.36 - 无穷大）相比，对于中度至重度疼痛患者，防止高度术后焦虑所需治疗人数为3（95%置信区间，1.35 - 5.0）。此外，通过重复测量方差分析评估（F[1,31] = 6.05，P = 0.02），接受治疗的患者通过患者自控镇痛所需的吗啡量更少。通过活动记录仪评估的静息/活动周期显示，出院后第一周干预组24小时的节律百分比更高（[21.16 ± 8.90] 对比安慰剂组 [14.00 ± 7.10]；[t = -2.41，P = 0.02]）。
这一发现表明术前褪黑素产生了具有临床意义的抗焦虑和镇痛作用，尤其是在术后24小时内。此外，它还改善了静息/活动昼夜节律强度的恢复。
