Successful management of a suspected air embolism during anaesthesia in a dog undergoing thoracic limb amputation

An 11-year-old, male, castrated, Springer Spaniel dog presented for right thoracic limb amputation due to chronic lameness. The dog was otherwise healthy. During brachial plexus dissection, end-tidal carbon dioxide dropped from 6.3 kPa to 1.3 kPa (47-10 mmHg) over 30 seconds, heart rate and spontaneous respiratory rate increased, and peripheral arterial haemoglobin oxygen saturation decreased from 98% to 78%. Initial patient assessment excluded equipment malfunction and cardiopulmonary arrest, prompting interdisciplinary conversation and targeted diagnostics. Arterial blood gas analysis, combined with the surgeons locating an entrainment point for air in the axillary vein, substantiated a diagnosis of vascular air embolism. Coordinated multidisciplinary interventions restored cardiorespiratory parameters within 40 minutes. The surgery was completed and the dog was successfully discharged. This report highlights the risk of venous air embolism during limb amputation and the importance of early recognition.