Gehling M, Tryba M, Niebergall H, Hufschmidt A, Schild M, Geiger K
Klinik für Anästhesiologie, Intensivmedizin und Schmerztherapie, Klinikum Kassel GmbH.
Schmerz. 2003 Oct;17(5):309-16. doi: 10.1007/s00482-003-0228-8.
The results of clinical studies have raised doubts on the effectiveness of regional sympathetic blocks with guanethidine (IVRSB) in patients suffering from complex regional pain syndrome (CRPS). We conducted a retrospective analysis of long-term results in our patients and searched for possible factors predicting long-term outcome after IVRSB:
After approval by our ethics commission and written informed consent, 42/44 patients were included. We documented diagnosis, history, therapy and long-term result from charts. Long-term results were also obtained from a questionnaire administered to the patients. These were defined as very good (reduction of pain > or =75%), good (pain reduction <75% and > or =50%), moderate (pain reduction <50% and > or =25%) or poor (pain reduction <25%). The association of a moderate or poor outcome with the factors age, gender, duration of time until therapy, pain intensity before therapy, dose of applied guanethidine and duration of therapy was calculated by odds ratio. Confidence intervals for the odds ratios were determined by Woolfs approximation.
After a mean duration of 18 months, the outcome was classified as very good in 14, good in 13, moderate in 5 and poor in 10 patients. An increased rate of moderate or poor outcome was associated with age<60 years (OR=4.00, CI 1.04-15.26), male gender (OR=2.93, CI 0.71-12.11) and duration of therapy>2 weeks (OR=3.27, CI 0.86-12.36). The factors duration of time until therapy, initial pain intensity and total dose of guanethidine were not associated with increased rates of moderate or poor outcome.
We only seldom observed a complete functional restoration after CRPS. Male patients <60 years showed an increased risk of developing chronic pain. It remains unclear whether the risk of chronic pain reflects different responses to therapy or differences in the natural course of the disease in our patients. A meta-analysis of randomised trials of IVRSB in CRPS failed to prove the effectiveness of this intervention. If other investigations confirm our impression, future studies of CRPS-treatments should be planned and analysed with regard to the possible influence of the natural course and different risks of chronic pain among patients with CRPS.
临床研究结果对胍乙啶区域交感神经阻滞（IVRSB）治疗复杂性区域疼痛综合征（CRPS）患者的有效性提出了质疑。我们对我们患者的长期结果进行了回顾性分析，并寻找预测IVRSB后长期结局的可能因素：
经我们的伦理委员会批准并获得书面知情同意后，纳入了42/44例患者。我们从病历中记录了诊断、病史、治疗和长期结果。长期结果也通过向患者发放的问卷获得。这些结果被定义为非常好（疼痛减轻≥75%）、好（疼痛减轻<75%且≥50%）、中等（疼痛减轻<50%且≥25%）或差（疼痛减轻<25%）。通过比值比计算中等或差的结局与年龄、性别、治疗前时间、治疗前疼痛强度、所用胍乙啶剂量和治疗持续时间等因素之间的关联。比值比的置信区间通过伍尔夫近似法确定。
平均18个月后，14例患者结局为非常好，13例为好，5例为中等，10例为差。中等或差的结局发生率增加与年龄<60岁（OR = 4.00，CI 1.04 - 15.26）、男性（OR = 2.93，CI 0.71 - 12.11）和治疗持续时间>2周（OR = 3.27，CI 0.86 - 12.36）相关。治疗前时间、初始疼痛强度和胍乙啶总剂量等因素与中等或差的结局发生率增加无关。
CRPS后我们很少观察到完全的功能恢复。60岁以下男性患者发生慢性疼痛的风险增加。目前尚不清楚慢性疼痛的风险是反映了对治疗的不同反应还是我们患者中疾病自然病程的差异。一项关于CRPS中IVRSB的随机试验的荟萃分析未能证明该干预措施的有效性。如果其他研究证实我们的观点，未来CRPS治疗的研究应考虑CRPS患者中疾病自然病程和慢性疼痛不同风险的可能影响来进行规划和分析。
