Using non-invasive monitors (such as blood pressure, O2 saturation, end-tidal CO2 pressure monitors and electrocardiograms), the application of total intravenous anesthesia with O2 mask in transthoracic endoscopic sympathectomy was evaluated. A total of 198 palmar hyperhidrosis patients were studied. In the study, the durations of surgery were 5-15 min (mean 8 min) with anesthesia duration of 8-20 min (mean 12 min), respectively. The cardiovascular system was quite stable during operation, with systolic blood pressures of 90-165 mmHg (mean 132 mmHg), diastolic blood pressures of 50-106 mmHg (mean 92 mmHg) and heart rates of 56-130 beats/min (mean 104 beats/min). The respiratory function was maintained within a safety range with O2 saturation of 95-100% (mean 99%) and end-tidal CO2 pressure of 32-40 mmHg (mean 36 mmHg). After surgery, the major discomfort was chest pain (132/198), but this could be improved with intravenous analgesics. Patients' consciousness returned within 1-3 min. After ensuring their general condition was stable, patients were discharged within 24 hr. Preliminary study showed that total intravenous anesthesia plus muscle relaxant, with O2 mask and assisted ventilation, could serve as a safe and simple anesthesia for palmar hyperhidrosis patients who received transthoracic endoscopic sympathectomy.