Adequate splanchnic oxygen saturation (SpO2) is essential for maintaining organ viability during and after surgery. There is a need for reliable continuous monitoring of organ oxygen saturation. A new photoplethysmographic (PPG) probe and signal processing system were developed. PPG signals from abdominal organs (bowel, liver, kidney) and the finger were obtained from 12 anaesthetised patients. The amplitudes of the abdominal organ PPGs were, on average, approximately the same as those obtained simultaneously from the finger. Preliminary SpO2 values from abdominal organs showed good agreement with those obtained simultaneously from a commercial finger pulse oximeter
