Postoperative (pressure) alopecia.

Postoperative localized alopecia has been reported most commonly after certain gynecologic and open heart surgery procedures, the likelihood of hair loss and the chance of permanence correlating with the length of the anesthesia and the intubation. Some cases of pressure-induced alopecia have been described after prolonged coma from other causes. Coma blisters have been reported after drug overdoses, but clinically similar blisters (not tested by biopsy) have been seen in other cases of coma. We present three cases of postoperative (pressure) alopecia and propose that both coma blisters and postoperative alopecia arise from the same phenomenon--probably pressure-induced ischemia.