[Pulse oximetry and capnometry in the prevention of perioperative morbidity and mortality]

Abstract

Oxygen saturation (SaO2) and end tidal CO2 determined by pulse oximetry and capnometry were monitored in 2440 surgical patients during elective head and neck, abdominal, traumatologic and orthopedic surgery. The incidence, severity and duration of hypoxemia and hypercarbia were studied as well as their causes. Equipment disconnections alarmed by capnometry were noted separately. Hypoxemia was defined as SaO2 < or = 90% and graded into three values of SaO2 and hypercarbia was defined as EtCO2 > or = 50 mmHg. Severe hypoxemia (SaO2 < or = 80%) occurred in 170 (8%) patients. A greater number of severe events occurred in children under 2 yr of age (p < 0.02). The pulse oximeter diagnosed hypoxemia before the signs and symptoms of hypoxemia were apparent (cyanosis or bradycardia). Severe hypoxemic episodes were unrelated to the duration of anesthesia. Equipment disconnections alarmed by capnometer were most frequent in head and neck surgery (p < 0.02). Capnometer alarmed disconnections before the signs of hypoxemia and hypercarbia occurred. No morbidity was documented in any patients who suffered an hypoxemia event. Pulse oximetry and capnometry enable early detection and removal of the majority of the ventilation mishaps before damage or even death occur.