Myocardial infarction masked by high level spinal anesthesia in a patient undergoing herniorrhaphy

Myocardial infarction (MI) is one of the leading causes of perioperative morbidity. Although evidence to prove significant reduction of perioperative MI with regional anesthesia is lacking, anesthesiologists still prefer this technique over general anesthesia for surgery involving the lower abdomen or lower extremities, especially in patients with cardiac risks. However, high level of sensory block during spinal anesthesia may obscure the referred pain from MI, which could contribute to the delay of diagnosis and treatment of an acute perioperative attack. We report a case of MI which occurred either intraoperatively or postoperatively, with symptoms that were masked by high level of sensory block to T₄ by spinal anesthesia. This perioperative MI was only diagnosed when the patient recovered from anesthesia in the post-anesthesia care unit (PACU).