Occurrence of Hypercarbia due to a Defective Unidirectional Valve / 대한마취과학회지

Hypercarbia can occur in spite of adequate ventilation if removal of carbon dioxide from the inspired gases is inadequate. Neither blood pressure nor heart rate is a reliable indicator of hypercarbia. A 53-year old male, ASA physical status II with mild hypertensive patient underwent primary repair because of rotator cuff tear of the shoulder. Anesthesia was induced with thiopental-succinylcholine and maintained with pancuronium- Halothane-N2O-O2 in a semiclosed circle system. We report occurrence of hypercarbia due to replacement with an incorrect unidirectional valve which is too small to function properly.