Raja S N, Treede R D, Davis K D, Campbell J N
Department of Anesthesiology/Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Anesthesiology. 1991 Apr;74(4):691-8. doi: 10.1097/00000542-199104000-00012.
The diagnosis of sympathetically maintained pain (SMP) is typically established by assessment of pain relief during local anesthetic blockade of the sympathetic ganglia that innervate the painful body part. To determine if systemic alpha-adrenergic blockade with phentolamine can be used to diagnose SMP, we compared the effects on pain of local anesthetic sympathetic ganglion blocks (LASB) and phentolamine blocks (PhB) in 20 patients with chronic pain and hyperalgesia that were suspected to be sympathetically maintained. The blocks were done in random order on separate days. Patients rated the intensity of ongoing and stimulus-evoked pain every 5 min before, during, and after the LASB and PhB. Patients and the investigator assessing pain levels were blinded to the time of intravenous administration of phentolamine (total dose 25-35 mg). The pain relief achieved by LASB and PhB correlated closely (r = 0.84), and there was no significant difference in the maximum pain relief achieved with the two blocks (t = 0.19, P greater than 0.8). Nine patients experienced a greater than 50% relief of pain and hyperalgesia from both LASB and PhB and were considered to have a clinically significant component of SMP. We conclude that alpha-adrenergic blockade with intravenous phentolamine is a sensitive alternative test to identify patients with SMP.
交感神经维持性疼痛（SMP）的诊断通常是通过评估支配疼痛身体部位的交感神经节局部麻醉阻滞期间的疼痛缓解情况来确立的。为了确定酚妥拉明进行的全身性α-肾上腺素能阻滞是否可用于诊断SMP，我们比较了20例疑似交感神经维持性慢性疼痛和痛觉过敏患者局部麻醉交感神经节阻滞（LASB）和酚妥拉明阻滞（PhB）对疼痛的影响。阻滞在不同日期随机进行。患者在LASB和PhB之前、期间和之后每5分钟对持续性疼痛和刺激诱发的疼痛强度进行评分。患者和评估疼痛程度的研究者对静脉注射酚妥拉明（总剂量25 - 35mg）的时间不知情。LASB和PhB所实现的疼痛缓解密切相关（r = 0.84），并且两种阻滞实现的最大疼痛缓解没有显著差异（t = 0.19，P大于0.8）。9例患者LASB和PhB后疼痛和痛觉过敏缓解超过50%，被认为具有临床上显著的SMP成分。我们得出结论，静脉注射酚妥拉明进行α-肾上腺素能阻滞是识别SMP患者的一种敏感的替代测试。
