Intravenous Regional Bretylium for the Treatment of Reflex Sympathetic Dystrophy

Systematic review of outpatient services for chronic pain control.

“…Eight controlled trials were found that assessed the analgesic effects of IRSBs 141,[148][149][150][151][152][153][154] in patients with RSD (Table 21). Sample sizes ranged from six to 21 patients.…”

“…Of the eight RCTs, two (17 patients in total) showed some advantage of IRSBs over control treatments. 150,153 Neither study used guanethidine. The remaining trials failed to show a significant difference in analgesic response between the IRSBs and the control treatments.…”

“…The major methodological problems of the studies were poorly defined diagnostic criteria, 150,152,153 inadequate washout periods, 150 incomplete cross-over, 151,153 open administration of treatments, 148 no description of the technique, 154 and a high proportion of withdrawals with no 'intention-to-treat' analysis. 149,153 There was no RCT evidence to support guanethidine use in IRSBs to treat RSD, but some evidence for ketanserin and bretylium. All the studies were small, so that there is substantial risk of false-negatives and even false-positives.…”

“…Two small studies, neither using guanethidine, did show significant relief. 150,153 There is thus some limited support for the technique but none for guanethidine as the active drug in the injection to relieve the pain associated with RSD. Only one RCT has ever shown analgesic effects of blocks with guanethidine.…”