Efficacy and clinical tolerance of parenteral pentoxifylline in the treatment of critical lower limb ischemia. A placebo controlled multicenter study. Norwegian Pentoxifylline Multicenter Trial Group.

A total of 114 patients with critical lower limb ischemia from 11 hospitals were randomized to either Pentoxifylline 600 mg or placebo given intravenously twice a day. Rest pain was evaluated both by the investigator and the patient. Pain was evaluated with the patient in the supine as well as in the sitting position using a pain score scale, a pain relief scale and a visual analogue scale. All patients underwent a clinical examination, measurement of ankle systolic blood pressure and arteriography. These arteriograms were evaluated by a radiologist who did not know which treatment had been given. If no beneficial effect of the treatment was observed after one week, further medication was discontinued. Otherwise the treatment continued for two additional weeks. There was no statistically significant difference in pain-free or absolute walking distance between the two groups. Evaluating the patients with the most pronounced amelioration of rest pain in the supine position (divided by 4 to divided by 2 points), there was a beneficial effect of Pentoxifylline compared to placebo. Evaluation of the total material did not, however, show any statistical significances between the groups. From further subgroup analysis excluding patients who had only slight pain at the entrance of the study, there was a significant improvement in rest pain in favour of Pentoxifylline following seven days of treatment. In this group the pain evaluated according to this visual analogue scale had decreased 37 points (54%) compared to 14 points (25%) in the placebo group. More side effects, mainly gastrointestinal, were observed in the Pentoxifylline group. Most of these could be eliminated by increasing the infusion time. Further investigations are necessary to evaluated the place of Pentoxifylline in the treatment of patients with critical limb ischemia.