ENHANCEMENT OF BUPIVACAINE CARDIOTOXICITY WITH CARDIAC-GLYCOSIDES AND BETA-ADRENERGIC BLOCKERS - A CASE-REPORT

Intercostal (IC) nerve blocks with a long-acting local anesthetic such as bupivacaine are often per- I formed for treatment of pain after thoracotomy (1,2). This anesthetic technique improves postoperative respiratory function, decreases the requirement for postoperative opioids, and shortens hospital stay (3). The technique of IC blocks, however, is not without complications. Pneumothorax (4), total spinal anesthesia (5,6), hypotension (7), and systemic toxic reactions have been reported. The latter manifests most frequently as central nervous system symptoms (CNS) (8), whereas myocardial toxicity (9,10) is not as common in clinical practice due to the large dose of drug required to produce this effect. We describe a case of cardiotoxicity induced with a low dose of bupivacaine for IC block in a patient who was treated with digoxin and metoprolol, both medications recognized to have high depressive potential on the cardiac conduction system. This is the first reported case that supports the experimental data (11–13) describing additive cardiotoxic interaction between bupivacaine and drugs used for treatment of cardiac conditions.