The Psychology of Human Action

Abstract

At the end of an uneventful operation maintained by a total intravenous anesthesia (TIVA) a patient started to buck against the endotracheal tube prompting the anesthetist to switch the anesthesia machine from a mandatory to a spontaneous breathing mode. He did this by first selecting the new ventilation mode from the software menu and then pressing a button to accept the chosen value. While doing so the anesthetist turned his attention briefly to a concurrent problem. Shortly after, the anesthetist returned his attention to the patient and all signs indicated adequate spontaneous breathing: chest excursions were regular; the capnography curve displayed a regular pattern; the expiratory minute volume was adequate; and the saturation was at 100%. Again, the patient started to buck against the tube and the anesthetist decided to extubate the patient. Shortly after the extubation, the saturation began to drop and the patient became cyanotic. The anesthetist then realized that the ventilator was still working in the volume-controlled mode and had not been switched into the spontaneous breathing mode as he initially thought.