When good pain turns bad

Classically, pain is viewed as being mediated solely by neurons. However, recent research has shown that activated glial cells (astrocytes and microglia) within the spinal cord amplify pain. These nonneuronal cells play a major role in the creation and maintenance of pathological pain. Glia become activated by immune challenges (viral or bacterial infection) and by substances released by neurons within the pain pathway. Activated glia amplify pain by releasing proinflammatory cytokines. Taken together, research findings suggest a novel approach to human pain control that targets glia. In addition, it is likely that such glial-neuronal interactions are not unique to pain, but rather reflect a general rule of sensory processing.     

右美托咪定对胃肠道开腹手术瑞芬太尼诱发痛觉过敏的影响

探讨术中泵注右美托咪定对瑞芬太尼所致术后痛觉过敏及不良反应的影响。60例择期开腹胃肠道手术患者,随机分成右美托咪定组（Ⅰ组,n=30）和对照组（Ⅱ组,n=30）。分别记录术后自主呼吸恢复时间、唤醒时间、拔管时间;记录术后30min、1h、2h、4h、6h的疼痛视觉模拟评分（VAS）及Ramsay镇静评分;记录术后24h内静脉镇痛泵的使用情况及术后不良反应。两组患者的术后恢复自主呼吸时间、唤醒时间及气管导管拔管时间相当,差异无统计学意义（P〉0．05）;术后30rain、1h、2h,Ⅰ组患者的VAS评分明显低于Ⅱ组患者,差异有统计学意义（P〈0．05）;Ⅰ组患者在术后30min、1h、2h、4h的Ramsay评分明显高于对照组,差异有统计学意义（P〈0．05）;Ⅰ组患者在术后初次按压镇痛泵的时间较Ⅱ组患者明显延长,24h内镇痛泵的按压次数Ⅰ组较Ⅱ组患者减少（P〈0．05）;两组患者术后均无呼吸抑制的发生,但Ⅰ组比Ⅱ组其他不良反应的发生率降低,差异有统计学意义（P〈0．05）。在开腹胃肠道手术的麻醉中使用右美托咪定可有效减少瑞芬太尼全身麻醉后痛觉过敏的发生率,并减少术后镇痛药的用量。