Valve Failure in the Gas Monitor: An Unusual Cause of Falsely Low Capnography Values Under General Anesthesia. Issue 6 (April 2020)

• Record Type: Journal Article
• Authors: Neira, Victor M.; Fagan, Brian; Milne, Andrew D.
• Is Part Of: A & A practice. Volume 14:Issue 6(2020)
• Publication Date: 2020-04
• Subjects: Analgesia -- Periodicals; Analgesia -- Case studies -- Periodicals; Anesthesiology -- Periodicals; Anesthesiology -- Case studies -- Periodicals; 617.9605
• DOI: 10.1213/XAA.0000000000001173
• Languages: English
• ISSNs: 2575-3126

Abstract

Abstract : We present a case in which the Dräger Primus (Dräger Medical AG&Co KG, Lüberck, Germany) anesthesia monitor displayed false readings of low end-tidal carbon dioxide (EtCO2 ) immediately after intubation. The patient's physical examination, vital signs, and arterial blood gases were normal. The ventilator, circuit, gas sample line, and water trap appeared intact and functional. A second gas analyzer revealed normal EtCO2 readings, correlating with blood gas values. The defective monitor gas flow rates and gas calibration values were inappropriately low. Partial opening of the solenoid zero valve allowed entrainment of room air, which caused artifactual dilution of the gas sample.