Brachial plexus injury after cardiac surgery. The role of internal mammary artery preparation: a prospective study on 1000 consecutive patients.

Brachial plexus injury is a typical complication after median sternotomy. A prospective study was performed on 1000 consecutive patients to determine whether preventive actions, including lower position and least possible opening of the sternal retractor, help to reduce the complication rate. Twenty-seven patients were observed with postoperative brachial plexus injury. Nerve conduction measurements and electromyography were performed. Patients without preparation of the internal mammary artery had a complication rate of less than 1%, whereas the complication rate of those patients with preparation of the internal mammary artery was as high as 10.6%. The main symptoms were continuous pain and motor and sensory disturbances. Most frequent were lesions corresponding to the roots C8-T1. Six patients had Horner's syndrome; three had ptosis only with no other signs of Horner's syndrome. Symptoms persisted in eight patients more than 3 months after the operation, and one patient still had intractable pain. Increasing use of internal mammary artery grafts in coronary artery bypass demands measures to protect the brachial plexus.