Hazards of epidural anesthesia in patients with previous vascular grafts

Two cases are described in which thrombosis of both limbs of an aortobifemoral bypass occurred after epidural anesthesia for a nonvascular operation. This has not previously been reported, and possible reasons for its occurrence are discussed. It seems likely that the hypotension associated with epidural anesthesia, particularly in patients already hypotensive or volume depleted, may precipitate this phenomenon. In addition, the sensory loss produced by the anesthetic may mask the signs and symptoms of acute vascular occlusion. Epidural anesthesia is not recommended in heparinized patients because of the risk of an epidural hematoma.