Anesthesiology 2000; 93:315-318

Reviewer: John F. Heath, M.D.

Eight of twenty patients studied by transcranial doppler of the middle cerebral artery demonstrated multiple cerebral microemboli during total hip arthroplasty under epidural anesthesia.  Embolic signals ranged from 1 to 200 episodes during surgery.  The signals were noted primarily during insertion  of a cemented femoral component.  One patient developed transient agitation and respiratory difficulty.  Echocardiography was not used.  No patient demonstrated a positive V/Q scan or postop confusion or stroke.  Cognitive studies were not performed.