Intravenous guanethidine in patients with reflex sympathetic dystrophy

Intravenous regional guanethidine Bier block (IVRGBB) has been used predominantly in Europe for treating reflex sympathetic dystrophy (RSD). Our experience in the United States, where its use has been limited, is reported.

Fifty-five patients received IVRGBB for RSD. Upper extremities received 20 mg (10 mg/ml) of guanethidine in 30-50 ml of 0.5% lidocaine; lower extremities received 40 mg in 40-75 ml of lidocaine (volume adjusted for size, weight, or prior adverse effect). Pain severity (mild, moderate, severe, excruciating) was obtained pretreatment. Pain severity and a global clinical assessment (GCA) (resolved, improved, no change, worse) were obtained following each treatment. The final GCA was analyzed vs: pretreatment score; age; sex; pain duration; number of treatments; and precipitating event. Adverse effects were documented.

Of 55 enrolled patients, 2 were lost to follow-up, and 2 returned 1 and 4 years later for repeat treatment. Therefore, 53 patients were evaluated for 55 treatments. Age: 38.2 +/- 14.8 (SD) (range 10-77) years. Sex: 11 males, 44 females. Average pain duration: 2.0 +/- 1.7 years (3 days-7 years). Final assessment occurred at 3.88 +/- 5.21 months (6 days-22/3 years). Effect on pain: resolution-9.1%; improved-14.5%; no change-61.8%; worsening-14.5%. No significant relationship was found between GCA and the factors evaluated. There was a significant positive linear association between pretreatment pain and post treatment GCA (P = 0.032). Fifty-six adverse effects occurred in 19 (34.5%) patients (nausea, vomiting, orthostatic hypotension, dizziness, diarrhea, weakness).

IVRGBB does not provide long-term pain relief and is associated with adverse effects in over 1/3 of patients.