Figure 11-29 Times to awakening (open circles) and tracheal extubation (closed circles) in patients who underwent minimally invasive direct coronary artery bypass surgery after an intravenous anesthesia with remifentanil-propofol or alfentanil-propofol. (From Ahonen J, Olkkola KT, Verkkala K, et al: A comparison of remifentanil and alfentanil for use with propofol in patients undergoing minimally invasive coronary artery bypass surgery. Anesth Analg 90:1269–1274, 2000.)