We report five patients who developed intraoperative
myocardial ischemia but were treated successfully with
nicorandil. Case 1; An 84 year-old male underwent emergent
laparotomy and ileolysis under inhalational plus thoracic
epidural anesthesia. During his emergence from
anesthesia, arterial pressure and heart rate increased abruptly due to excitement, leading to ST-T depression on V5 lead.
Bradycardia and
hypotension developed subsequently. Immediately after i.v.
injections of
nicorandil 4 mg and
atropine 0.3 mg, ST-T change and hemodynamics improved dramatically. Case 2; A 67 year-old male underwent
esophagectomy under inhalational plus thoracic
epidural anesthesia. Following the completion of surgery, elevation of ST-T developed suddenly on lead II, though hemodynamics were not compromised. ST-T elevation disappeared immediately after
nicorandil 6 mg and continuous infusion of
nitroglycerin (TNG) was initiated. Case 3; A 71 year-old female underwent aortic valve replacement under high-dose
fentanyl anesthesia. Shortly after starting
cardiopulmonary bypass (CPB), ST-T segment on leads II and V5 was elevated suddenly. This was accompanied by severe
pulmonary hypertension suggestive of severe left ventricular failure. Shortly after
nicorandil 4 mg via a pulmonary artery (PA)
catheter, ST-T segment returned to the baseline and pulmonary arterial pressure was normalized. Case 4; A 61 year-old male underwent coronary revascularization under high-dose
fentanyl anesthesia. During weaning from CPB, elevation of ST-T segment occurred on leads II and V5. ST change improved, responding to
nicorandil 6 mg en bolus via a PA
catheter. Case 5; A 67 year-old male underwent coronary revascularization under high-dose
fentanyl anesthesia. He was unable to be weaned from CPB for several hours because of frequent and repeated attacks of
ventricular tachycardia and
ventricular fibrillation. The
arrhythmia did not respond to various kinds of treatments including
intra-aortic balloon pumping and continuous infusions of inotropes,
anti-arrhythmic drugs and anti-anginal drugs. In spite of repeated intracoronary
injections of TNG, graft flow to the left anterior descending branch remained low at 40 ml.min-1. After an intracoronary injection of
nicorandil 1 mg, however, blood flow increased to 100 ml.min-1, resulting in a marked reduction in frequency of ventricular
arrhythmia. The patient came off bypass successfully. In each case, intraoperative
myocardial ischemia was treated successfully with
nicorandil. Neither
hypotension nor
arrhythmia resulted from its bolus injection.
Nicorandil might be a useful therapeutic tool for
myocardial ischemia during
anesthesia.