The inability to detect expired carbon dioxide after endotracheal intubation as a result of one-way valve obstruction of the endotracheal tube.

Failure to tracheally intubate and ventilate the lungs is a major cause of anesthesia morbidity. Expired carbon dioxide monitoring has become a standard for assessing correct endotracheal tube placement. We present a case of failure to detect expired carbon dioxide after successful intubation resulting from a one-way valve obstruction of the endotracheal tube.