超前镇痛的相关研究进展

超前镇痛是通过防止外周和中枢敏化来降低伤害性刺激引起的痛觉过敏和痛觉异常的一种镇痛方法.现介绍超前镇痛的机制、临床常用方法及药物,并展望超前镇痛亟待解决的问题.     

超前镇痛的相关研究进展

超前镇痛是通过防止外周和中枢敏化来降低伤害性刺激引起的痛觉过敏和痛觉异常的一种镇痛方法.现介绍超前镇痛的机制、临床常用方法及药物,并展望超前镇痛亟待解决的问题.     

围术期镇痛对术后炎症反应的影响

手术创伤后局部组织损伤产生炎症介质,包括PGs,细胞因子等,它们释放人血产生全身炎症反应,炎症介质还可产生疼痛或痛觉增敏。围术期镇痛应该采用多种药物、方法的多模式镇痛,其中局麻药硬膜外镇痛具有较重要的作用,结合阿片类镇痛药、NSAIDs、超前镇痛等,通过抑制交感活化及炎症介质产生等机制对减轻术后炎症反应,促进术后恢复及结局改善具有重要意义。     

乳腺癌根除术中联合应用帕瑞昔布钠与地佐辛超前镇痛的临床效果

目的：评价乳腺癌根除术中联合应用帕瑞昔布钠与地佐辛超前镇痛的临床效果。 方法：将170例行乳腺癌根除术的患者分为对照组、超前镇痛组、联合超前镇痛组，分别于麻醉诱导前注射生理盐水、帕瑞昔布钠、帕瑞昔布钠+地佐辛。记录患者术后2、6、12、24、48 h的视觉模拟评分（VAS），比较各组的镇痛效果，并比较各组心血管反应与不良反应的发生情况。 结果：超前镇痛与联合超前镇痛组术后各时间点VAS评分均明显低于对照组（均P<0.05），联合超前镇痛组术后2 h的VAS评分明显低于超前镇痛组（P<0.05），术后6~48 h各时间点VAS评分虽仍低于超前镇痛组，但差异无统计学意义（均P>0.05）。诱导开始前至手术结束，超前镇痛与联合超前镇痛组的心率（HR）与平均动脉压（MAP）均低于对照组，且在插管后5 min至手术结束时明显低于对照组（均P<0.05），但两个超前镇痛组间无统计学差异（均P>0.05）。超前镇痛与联合超前镇痛组不良反应发生率均明显小于对照组（均P<0.05），联合超前镇痛组恶心、呕吐、头晕的发生率大于超前镇痛组，但差异无统计学意义（P>0.05）。 结论：帕瑞昔布钠和地佐辛联合应用于乳腺癌根除术超前镇痛临床效果良好，不会引发患者心血管反应的增多，但会可能增加患者呕吐恶心、头晕等不良反应。     

超前镇痛的研究现状

本文通过阐述超前镇痛的机理，对超前镇痛的有关临床研究状况作了介绍，并对超前镇痛的临床效果作了初步评价。目前超前镇痛的方法主要包括：１、区域阻滞；２、应用ＮＳＡＩＤ；４、联合镇痛措施。     

全膝关节置换围手术期镇痛进展

全膝关节置换术手术技术及术后功能锻炼是决定手术成功与否的两个重要因素,而术后功能锻炼很大程度上取决于围手术期镇痛的效果.目前研究较多的围手术期镇痛概念主要是超前镇痛和多模式镇痛,传统方法主要是口服或静注阿片药物、患者自控静脉镇痛、患者自控硬膜外镇痛、单次或连续股神经阻滞等,新的多模式镇痛方法及给药途径近年也不断涌现,包括患者自控硬膜外镇痛联合连续股神经阻滞镇痛、智能注射泵系统、一些非侵入途径如盐酸芬太尼透皮电刺激及患者自控经鼻给药途径等.该文就全膝关节置换术超前镇痛、术中术后镇痛等相关研究进展作一综述.     

“超前镇痛”的某些发现及其应用前景

最有效的术后疼痛治疗应当是预先给药,超前阻止或减轻手术过程中中枢神经的致敏作用以及感受伤害的传入,达到减轻术后疼痛、延长镇痛时间和减少止痛药的需求量。本文就有关吗啡、氯胺酮和芬太尼的超前镇痛效果进行评价,以及探讨超前镇痛的作用机理。     

氯诺昔康对切口痛大鼠痛觉过敏的影响

急性创伤等伤害性刺激可通过外周和中枢双重机制导致痛觉过敏的发生[1].氯诺昔康是非甾体类镇痛抗炎药,胃肠耐受性好,常用于超前镇痛[2,3].本研究拟评价氯诺昔康对切口痛大鼠痛觉过敏的影响,以探讨其对急性创伤性疼痛的镇痛效应.     

超前镇痛的研究现状

本文通过阐述超前镇痛的机理、对超前镇痛的有关临床研究状况作了介绍,并对超前镇痛的临床效果作了初步评价。目前超前镇痛的方法主要包括:①区域阻滞;②应用阿片类药物;③应用NSAID;④联合镇痛措施。     

曲马多超前镇痛对腹腔镜胆囊切除术术后疼痛的观察

超前镇痛是在伤害性刺激作用于机体之前采取一定的措施,防止中枢敏化,减少或消除伤害引起的疼痛.但关于超前镇痛是否有临床意义,目前还存在争议.曲马多是中枢性镇痛药,对μ受体有一定的亲和力,且可抑制神经元对5-羟色胺（5-HT）和去甲肾上腺素（NA）的摄取,促进5-HT的释放,产生较强的镇痛效果.腹腔镜胆囊切除术（LC）后仍存在一定程度的疼痛,需要采用有效的镇痛措施.但目前仍没有一种较为满意的镇痛方法.本研究采用术前及术毕分别给予曲马多镇痛,观察曲马多超前镇痛效果.     

Preemptive analgesia: an unsolved problem

Preemptive analgesia studies have provided mixed results, some showing benefit and others no benefit, whereas others have shown small differences that are probably not clinically useful. There is no consensus yet about whether preemptive analgesia is a clinically useful tool. This review examines the mechanisms of preemptive analgesia before surveying the recent literature. A new definition of preemptive analgesia is proposed that accommodates the need for a broader definition. Recently published trials confirm that confusion exists about what preemptive analgesia is, how to distinguish it from simple analgesia, and how to design trials that truly assess preemptive analgesia, defined as analgesia that is capable of modifying the central excitatory responses.     

超前镇痛护理理念用于食管癌患者术后镇痛

目的探讨超前镇痛护理理念对食管癌患者术后疼痛控制的影响。方法随机将188例食管癌手术患者分为常规镇痛组(n=93)和超前镇痛组(n=95)。常规镇痛组实施常规镇痛护理,即术前行疼痛知识宣教,术后应用Prince-Henry评分法定时评估患者疼痛,根据评分行针对性镇痛护理;超前镇痛组实施超前镇痛护理,即在前者基础上增加术前超前镇痛知识宣教,术后在执行各临床操作前行预见性疼痛评估,根据评分行预见性镇痛处理。比较两组患者术后24h、48h、72h疼痛评分,术后首次下床活动时间,肺部并发症发生率。结果两组术后24h、48h、72h疼痛评分比较,干预主效应P<0.05;超前镇痛组下床活动时间较常规镇痛组显著提前,肺部并发症发生率显著低于常规镇痛组(P<0.05,P<0.01)。结论超前镇痛护理理念对食管癌患者术后疼痛控制有积极的作用,有利于患者早日康复。     

Preemptive analgesia I: physiological pathways and pharmacological modalities

PURPOSE: This two-part review summarizes the current knowledge of physiological mechanisms, pharmacological modalities and controversial issues surrounding preemptive analgesia. SOURCE: Articles from 1966 to present were obtained from the MEDLINE databases. Search terms included: analgesia, preemptive; neurotransmitters; pain, postoperative; hyperalgesia; sensitization, central nervous system; pathways, nociception; anesthetic techniques; analgesics, agents. Principal findings: The physiological basis of preemptive analgesia is complex and involves modification of the pain pathways. The pharmacological modalities available may modify the physiological responses at various levels. Effective preemptive analgesic techniques require multi-modal interception of nociceptive input, increasing threshold for nociception, and blocking or decreasing nociceptor receptor activation. Although the literature is controversial regarding the effectiveness of preemptive analgesia, some general recommendations can be helpful in guiding clinical care. Regional anesthesia induced prior to surgical trauma and continued well into the postoperative period is effective in attenuating peripheral and central sensitization. Pharmacologic agents such as NSAIDs (non-steroidal anti-inflammatory drugs) opioids, and NMDA (N-methyl-D-aspartate) - and alpha-2-receptor antagonists, especially when used in combination, act synergistically to decrease postoperative pain. CONCLUSION: The variable patient characteristics and timing of preemptive analgesia in relation to surgical noxious input requires individualization of the technique(s) chosen. Multi-modal analgesic techniques appear most effective.     

Preemptive analgesia or balanced periemptive analgesia?

"Preemptive analgesia" means that analgesia given before the painful stimulus prevents or reduces subsequent pain. The concept of preemptive analgesia originates from basic science and experimental studies. However, in some clinical studies preemptive effect is not always present. The authors think that it happens for: differences among experimental models and clinical reality, wrong use of some pharmacological knowledges, some methodological errors in clinical research. The authors analyze these factors and review in a critical manner clinical studies on preemptive analgesia. In some operations, only one administration of an analgesic drug, before surgery, is not sufficient to produce an evident preemptive effect. Postoperative pain can be reduced making a pharmacological treatment before surgery, for the whole time of painful stimulus. For this reason, the term "preemptive analgesia", like "analgesia given before surgery" is not adequate. The authors suggest that the concept of prevention of postoperative pain is well defined by the term of "balanced periemptive analgesia"; it is a new approach that use many modalities of analgesia in different times to prevent and control painful stimulus for the whole time of its origin: before and/or during operation and, if necessary, in the postoperative period for the residual pain.     

Preemptive analgesia II: recent advances and current trends

PURPOSE: This two-part review summarizes the current knowledge of physiological mechanisms, pharmacological modalities and controversial issues surrounding preemptive analgesia. SOURCE: Articles from 1966 to present were obtained from the MEDLINE databases. Search terms included analgesia, preemptive; neurotransmitters; pain, postoperative; hyperalgesia; sensitization, central nervous system; pathways, nociception; anesthetic techniques; analgesics, agents. Principal findings: In Part I of this review article, techniques and agents that attenuate or prevent central and peripheral sensitization were reviewed. In Part II, the conditions required for effective preemptive techniques are evaluated. Specifically, preemptive analgesia may be defined as an antinociceptive treatment that prevents establishment of altered central processing of afferent input from sites of injury. The most important conditions for establishment of effective preemptive analgesia are the establishment of an effective level of antinociception before injury, and the continuation of this effective analgesic level well into the post-injury period to prevent central sensitization during the inflammatory phase. Although single-agent therapy may attenuate the central nociceptive processing, multi-modal therapy is more effective, and may be associated with fewer side effects compared with the high-dose, single-agent therapy. CONCLUSION: The variable patient characteristics and timing of preemptive analgesia in relation to surgical noxious input require individualization of the technique(s) chosen. Multi-modal analgesic techniques appear more effective.     

Preemptive analgesia in foot and ankle surgery

Central neuroplasticity, or changes in CNS processing due to surgical nociception. can amplify postoperative pain. As a result, a hyperalgesic state called wind-up can occur, having debilitating effects on postoperative patients. Preemptive analgesia works to prevent this process and results in a more positive surgical experience. Inhibition of afferent pain pathways by use of local anesthetic blocks, altered perception of pain with opioid use, and inhibition of pain pathways by NMDA receptor antagonists are examples of preemptive analgesia. Using a combination of preemptive modalities and addressing patients' perceptions can aid in interrupting pathologic pain cycles. Positive and modest results have been obtained from animal and human preemptive trials, yet basic pathophysiology demonstrates the validity and importance of preemptive analgesia. Future studies are needed to test effective blockade of afferent input while controlling perception, hyperalgesia, and NMDA receptor activity. The Agency for Health Care Policy and Research now recommends a multifaceted approach to postoperative pain. The goal in pain management is to inhibit destructive pain pathways, maintain intraoperative analgesia, and prevent central sensitization. Preliminary results of multimodal preemptive analgesia trials continue to be promising.     

Preemptive analgesia by intravenous low-dose ketamine and epidural morphine in gastrectomy: a randomized double-blind study

BACKGROUND: Morphine and ketamine may prevent central sensitization during surgery and result in preemptive analgesia. The reliability of preemptive analgesia, however, is controversial. METHODS: Gastrectomy patients were given preemptive analgesia consisting of epidural morphine, intravenous low-dose ketamine, and combinations of these in a randomized, double-blind manner. Postsurgical pain intensity was rated by a visual analog scale, a categoric pain evaluation, and cumulative morphine consumption. RESULTS: Preemptive analgesia by epidural morphine and by intravenous low-dose ketamine were significantly effective but not definitive. With epidural morphine, a significant reduction in visual analog scale scores at rest was observed at 24 and 48 h, and morphine consumption was significantly lower at 6 and 12 h, compared with control values. With intravenous ketamine, visual analog scale scores at rest and morphine consumption were significantly lower at 6, 12, 24, and 48 h than those in control subjects. The combination of epidural morphine and intravenous ketamine provided definitive preemptive analgesia: Visual analog scale scores at rest and morphine consumption were significantly the lowest at 6, 12, 24, and 48 h, and the visual analog scale score during movement and the categoric pain score also were significantly the lowest among the groups. CONCLUSION: The results suggest that for definitive preemptive analgesia, blockade of opioid and N-methyl-d-aspartate receptors is necessary for upper abdominal surgery such as gastrectomy; singly, either treatment provided significant, but not definitive, postsurgical pain relief. Epidural morphine may affect the spinal cord segmentally, whereas intravenous ketamine may block brain stem sensitization via the vagus nerve during upper abdominal surgery.