Tourniquet paralysis in microsurgery.

Tourniquet paralysis is a serious complication after surgery. The authors report 15 cases recorded in their institution from 1972 to 1992. Seven were a consequence of routine operations on the upper limb and 8 were after microsurgical procedures. In the first group, the incidence of tourniquet paralysis was 1 in 7000 and this does not differ from published reports. In the second group, the incidence of complications is higher: 1 in 4300 cases. In all 15 cases the Tinel sign was absent. Great care was taken to distinguish all the painful conditions which ranged from simple hyperalgesia to allodynia and causalgia. The distressing aspect of tourniquet paralysis is that all the main nerves of the upper limb (median, radial and ulnar), distally to the elbow, are usually affected by the paralysis. In the two groups, the three nerves were affected in 13 cases and the ulnar nerve was partially spared in 3 cases. In both groups the radial nerve was more severely affected. It took an average of 105 days for complete recovery for the first group (range, 30-210 days) and 115 days for the second group (range, 20-180 days). Only in 1 patient in the first group was functional recovery incomplete. According to the authors' experience, general safety factors should be considered before using tourniquet. The tourniquet should be prohibited in patients with congenital susceptibility to nerve compression and should be used with caution in cases of underlying coagulation disorders and neuropathies, in tiny cachetic patients and in patients with systemic lupus erythematosus. In microvascular procedures its use should be limited to the first phase of replantation.