[Obstructive respiration disorders. An aneurysm of the ventilator tubing during general anesthesia].

Technical problems during anaesthesia are important causes of anaesthesia-related deaths and brain damage. During general endotracheal anaesthesia for ophthalmic surgery (41-year-old man, ASA 1) we observed an increase in inspiratory pressure without other clinical changes. Disconnection and ventilation with a resuscitation bag showed normal inspiratory pressures. Inspection demonstrated an obstruction due to an aneurysm of the inner layer of the inspiratory tubing. The classification of this rare blockage of ventilation differs in the literature (pressure, hypoventilation, hypercarbia). In addition, it demonstrates the principal problem of clinical decision-making during anaesthesia based on monitoring information. Strategies for responding to alarms indicating hazards of ventilation must be based on immediate restoration of sufficient ventilation, and not primarily on detecting the cause.