The purpose of this study was to evaluate circulatory and respiratory responses to a breath-holding stress test in surgical patients at the bed-side using continuous and non-invasive monitoring with arterial tonometry and pulse oxymetry. Sixty-one patients were assigned into four groups: normal healthy patients(Cont), elderly patients(Elder), hypertensive patients(HT) and diabetic patients(DM). The breath-holding stress test was conducted in the supine position at the functional residual capacity level and in room air. Breath-holding time, changes in heart rate(HR), mean arterial pressure(MAP), arterial oxyhemoglobin saturation using a pulse oxymeter(SpO<SUB>2</SUB>) and the recovery time of SpO<SUB>2</SUB> were measured. Breath-holding time was significantly shorter in the HT group(30±2.0sec, p<0.05) and tended to be shorter in the Elder group(31±3.0sec, p=0.08) compared with the Cont group(41±2.9sec). The maximum mean arterial blood pressure(Max-MAP) was higher in the Elder(105±4.0mmHg)(p<0.05) and HT(128±5.6mmHg)(p<0.05) groups compared with the Cont group(93±4.0mmHg). However, ΔMAP, ΔHR, Min-SpO<SUB>2</SUB>, and ΔSpO<SUB>2</SUB> were not significantly different among the four groups. Our results suggest that non-invasive continuous monitoring facilitates evaluation of stress responses to breath-holding in preoperative patients, and that the breath-holding stress test causes sympathetic augmentation, resulting in increases in MAP and HR by approximately 15%, concomitant with a decrease in SpO<SUB>2</SUB> to 90-94%. The magnitude of the response is similar regardless of age and existence of HT and DM.