ABSTRACT
In order to know which monitors would alarm, three important factors must be considered: where in the circuit has the disconnection taken place: whether the patient is breathing spontaneously or being ventilated; and what alarm parameters have been set. Point of disconnection – working from the patient end to the anaesthetic machine, a disconnection in the breathing circuit can occur between: the catheter mount and the airway device; the HME filter and the catheter mount; the breathing circuit and the HME filter; and the anaesthetic machine and the breathing circuit. If disconnection occurs in the presence of a trained, vigilant anaesthetist, then theoretically it should be identified rapidly with no significant consequences. A ventilated patient, following a disconnection, would remain apnoeic, oxygen saturations would fall, would become hypoxic and, if not corrected, there would be associated Electrocardiography changes, hypotension and eventually the patient would suffer a cardiac arrest.
