We report the occurrence of severe ventricular arrhythmias in a patient with isovaleric acidemia during general anesthesia for suction lipectomy. The timing of events and character of the ECG changes are most consistent with bupivacaine toxicity after subcutaneous injection of tumescence solution containing this local anesthetic. The patient had previously documented carnitine deficiency, a condition which, we speculate, may lower the threshold for bupivacaine induced cardiotoxicity. We review clinical considerations in isovaleric acidemia and conclude that the use of bupivacaine in these patients probably should be avoided.