Hypercapnia due to rupture of the unidirectional valve in the inspiratory limb of the breathing system after induction of general anesthesia--a case report.

Malfunction of either inspiratory or expiratory check valve in a breathing circuit system may allow carbon dioxide (CO2) rebreathing and result in hypercapnia. The subsequent increase of PaCO2 may entail increased sympathetic activity which in turn causes serious problems such as tachyarrhythmia and myocardial ischemia, particularly in patients who have history of coronary artery disease (CAD). Here, we report an incident of rupture of the inspiratory valve in the breathing circuit which happened to a patient during induction of general anesthesia and eventuated in markedly heightened end-tidal CO2 (EtCO2) of the patient. The recognition, related complications and management of the inspiratory valve malfunction are discussed.