Fig. 4. Effects of propofol ( circles ) and remifentanil alone ( squares ) and in combination with propofol 0.8 mg · kg−1· min−1( triangles ) on mean evoked changes in heart rate (ΔHR; A and C ) and mean arterial pressure (ΔMAP; B and D ). Mean (SD, n = 5). Comparison with control:* P < 0.05;** P < 0.01;*** P < 0.001.