Suspected venous air embolism during thoracic limb amputation in a dog

A six-year-old dog was anaesthetised for the amputation of her left forequarter. Preoperative haematology, biochemistry and physical examination were unremarkable. Twenty minutes into surgery, a sudden decrease in end tidal carbon dioxide (50–14 mm Hg) and arterial haemoglobin oxygen saturation (95–87 per cent) was noted. After briefly excluding some differentials, an iatrogenic venous air embolism (VAE) was suspected secondary to the dissection of the axillary vein. The vein was clamped and mechanical ventilation initiated delivering 100 per cent oxygen. The surgery was completed, the dog was recovered and closely monitored. The animal was discharged three days after the event. This article discusses the pathophysiology, diagnosis, different treatments and outcome of a suspected VAE. This case emphasises the importance of an early recognition of this complication during procedures such as limb amputations.