Werner Mads U, Lassen Birgit, Kehlet Henrik
Acute Pain Service, Department of Anesthesiology, Hvidovre University Hospital, Copenhagen, Denmark.
Reg Anesth Pain Med. 2002 May-Jun;27(3):254-60. doi: 10.1053/rapm.2002.30664.
Glucocorticoids are well-known adjuvant analgesics in certain chronic pain states. There is, however, a paucity of data on their analgesic efficacy in acute pain. Therefore, the aim of the study was to examine the analgesic effects of dexamethasone in a validated burn model of acute inflammatory pain in humans.
Twenty-two volunteers were investigated in a double-blind, randomized, placebo-controlled cross-over study. Intravenous dexamethasone 8 mg or placebo was administered on 2 separate study days. Two hours after drug administration, a first-degree burn injury was produced on the medial aspect of the nondominant calf (12.5 cm2, 47 degrees C for 7 minutes). Quantitative sensory testing included pain ratings to thermal and mechanical stimuli (visual analog scale [VAS]), assessments of thermal and mechanical detection thresholds, and areas of allodynia and secondary hyperalgesia.
The burn injury induced significant increases in erythema (P <.0001) and hyperalgesia (P <.001) in both groups. Pain ratings and development of tactile allodynia during the burn did not differ between dexamethasone and placebo treatments (P >.6). There were no significant differences between treatments in regard to skin erythema (P >.8), thermal or mechanical thresholds (P >.2), thermal or mechanical pain response (P >.2), or mechanical secondary hyperalgesia (P >.2). Dexamethasone had no analgesic effects in normal skin.
The study indicates that systemic administration of dexamethasone 2 hours before a burn injury does not reduce the inflammatory-mediated changes in quantitative sensory thresholds, pain perception, or skin erythema in humans.
糖皮质激素是某些慢性疼痛状态下广为人知的辅助镇痛药。然而，关于其在急性疼痛中的镇痛效果的数据却很匮乏。因此，本研究的目的是在经过验证的人类急性炎症性疼痛烧伤模型中检测地塞米松的镇痛作用。
在一项双盲、随机、安慰剂对照的交叉研究中对22名志愿者进行了调查。在2个不同的研究日分别静脉注射8毫克地塞米松或安慰剂。给药2小时后，在非优势小腿内侧造成一度烧伤（12.5平方厘米，47摄氏度，持续7分钟）。定量感觉测试包括对热刺激和机械刺激的疼痛评分（视觉模拟量表[VAS]）、热检测阈值和机械检测阈值的评估，以及痛觉过敏和继发性痛觉过敏区域的评估。
两组的烧伤均导致红斑（P<.0001）和痛觉过敏（P<.001）显著增加。地塞米松组和安慰剂组在烧伤期间的疼痛评分和触觉性痛觉过敏的发展情况无差异（P>.6）。在皮肤红斑（P>.8）、热阈值或机械阈值（P>.2）、热痛反应或机械痛反应（P>.2）或机械性继发性痛觉过敏（P>.2）方面，各治疗组之间无显著差异。地塞米松对正常皮肤无镇痛作用。
该研究表明，在烧伤前2小时全身给予地塞米松并不能减轻人类炎症介导的定量感觉阈值、疼痛感知或皮肤红斑的变化。
