2020 Volume 40 Issue 5 Pages 469-474
A 67-year-old male patient underwent off-pump coronary artery bypass（OPCAB）surgery under general anesthesia. The surgery was uneventful until the bilateral internal thoracic arteries were dissected free from the chest wall. When a wound retractor was applied to median sternotomy incision, invasive blood pressure（IBP）of the left radial artery（RA）decreased. Intravenous administration of vasopressors failed to increase IBP of the left RA. Non-IBP（NIBP）of the right upper arm was higher than IBP of the left RA. There were no remarkable changes in cardiac function evaluated by transesophageal echocardiography and pulmonary artery catheter. We inserted a catheter into the left femoral artery for IBP monitoring and continued surgical procedures. When the wound retractor was removed, the discrepancy between IBP of the left RA and NIBP of the right upper arm disappeared. At the time of tracheal extubation in the operation room, remarkable muscle weakness of the left upper limb was found. In addition, the patient complained of pain on the left upper limb and paresthesia on the ulnar side of forearm on the first post-operative day. Neurological examinations revealed ulnar nerve palsy. We concluded that thoracic outlet syndrome was caused by the wound retractor during OPCAB surgery.
