The Effectiveness of Labetalol for Treating Esmolol-resistant Tachycardia in a Patient Who was Under General Anesthesia : A case report

ABSTRACT

Esmolol is a cardioselective beta-blocker with a very rapid onset of action and a short half-life. Labetalol is a combined alpha- and beta-adrenoceptor blocking agent. It is a nonselective antagonist at beta-adrenoceptors and a competitive antagonist of postsynaptic alpha 1-adrenoceptors. A 51 year old female patient was transferred to the operating room for performing spinal fusion under general anesthesia. She had no operation and medication history. The initial heart rate was 150 beats/min. Despite administering several bolus injections of esmolol, the heart rate was not decreased to under 130 beats/min. But the heart rate was decreased to 100 beats/min after the administration of labetalol 5 mg and this rate was maintained without an additional injection. The vital signs were stable until the operation was finished and the patient recovered uneventfully in the recovery room. The postoperative laboratory findings revealed that she had hyperthyroidism. We report here on an anesthetic experience of effective labetalol treatment for esmolol-resistant tachycardia in a patient who was under general anesthesia.