The hemodynamic effects of isoflurane before and after sternotomy in patients undergoing coronary artery bypass...

The hemodynamic effects of isoflurane were studied in 30 patients undergoing coronary artery bypass grafting, and receiving high dose of fentanyl (40 micrograms/kg). In 15 patients, isoflurane 2% was administered for ten minutes before sternotomy, while the same concentration of isoflurane was administered in the other 15 patients after sternotomy for the same interval of time. Isoflurane administration before sternotomy produced a significant decrease in cardiac index and mean arterial pressure, without a significant change in systemic vascular resistance or other hemodynamic variables. On the other hand, when isoflurane was used to counteract sternotomy-induced hypertension, it produced a significant decrease of systemic vascular resistance, associated with a significant increase in cardiac index.