THE DETECTION OF PERIPHERAL VENOUS PULSATION USING THE PULSE OXIMETERAS A PLETHYSMOGRAPH

The pulse oximeter can serve as a sensitive photoelectric plethysmogra ph in the operating room. It was noted in several cases that the pleth ysmographic waveform showed a high degree of variability during diasto le. Three patients are described with discrete diastolic peaks on the plethysmograph. Further investigation revealed that these diastolic pe aks appear to correlate with peripheral venous pulsation, which seems to have a central venous origin. Evidence is presented that the plethy smographic detection of the venous pulse may be useful in estimating t he changing volume status of the patient.