Loss of consciousness on turning the patient

An 82 year old man underwent elective removal of a common bile duct stent by endoscopic retrograde cholangiopancreatography (ERCP). He had been fit and well before the procedure. His medical history was unremarkable apart from longstanding intermittent right upper quadrant pain. He took omeprazole tablets 20 mg once daily. The procedure was successful and lasted about 20 minutes, during which time he was given no intravenous fluid. At the end of the procedure he was turned from the prone to the supine position in the ERCP suite. At once his oxygen saturation, as measured by pulse oxymetry, dropped to 70% and he became profoundly hypotensive, with a pulse of 50 beats/min. He was unresponsive, with a Glasgow coma scale of 3/15. Immediate resuscitation with oxygen and fluid restored his oxygen saturation and blood pressure, but he remained unresponsive. A 12 lead electrocardiogram showed massive anterior ST segment elevation with reciprocal changes. He was urgently moved to the cardiology catheterisation laboratory for primary percutaneous coronary intervention because myocardial infarction was suspected, but on arrival his electrocardiogram was normal. Generalised hypertonicity with brisk reflexes and upgoing planters were noted at this stage. Because he was haemodynamically stable, computed tomography of the head was performed without delay to rule out an acute intracranial bleed (figs 1⇓ and 2⇓). Fig 1 Axial computed tomogram of the head Fig 2 Sagittal computed tomogram of the head ### 1 What do the computed tomograms show? #### Short answer The computed tomograms of the head show large quantities of air in the cerebral vasculature. #### Long answer Figures 3⇓ and 4 ⇓ show axial …