A Simple Rewarming Method to Restore Pulse Oximeter Signal Detection

Abstract

To the Editor We describe a simple method to restore the pulse oximeter signal using a noninvasive technique. Written permission for publication of this report was obtained from the patient. After 1 hour of surgery in a 24-year-old ASA physical status II obese women undergoing gastric bypass surgery, the pulse oximeter signal became unobtainable despite otherwise normal vital signs (noninvasive blood pressure 130/80 mm Hg, heart rate 95 bpm, and esophageal temperature 37°C). A forced-air warming blanket was in use at the time. Several attempts to warm the fingers as well as applying the sensor to different peripheral sites did not result in a normal-appearing signal. A pair of disposable gloves were filled with hot water (38°C) and the inflated glove fingers were placed between the patient's fingers (Fig. 1). Seven minutes later, a normal-appearing pulse oximetry signal and plethysmographic waveform returned and remained unchanged for the remainder of surgery; after that, the gloves were removed.Figure 1: The hot water-inflated fingers of double gloves (temperature 38°C) were placed between the patient's fingers for rewarming and restoring the pulse oximeter signal.Digital block1 and topical application of EMLA cream2 have also been described to restore the pulse oximeter signal. Our described method is easily applied, relatively inexpensive, and the required materials are readily available. One caution is that the temperature of the water used to fill the gloves should be no more than 37°C to 38°C (body temperature) to prevent any likelihood of burns to the skin. Ahed Zeidan, MD Mohamed Ahmed Abdullah, CRNA Department of Anesthesiology Procare Riaya Hospital Al-khobar, Kingdom of Saudi Arabia [email protected]