Case Report: Local anaesthetic systemic toxicity secondary to presumed thoracostomy tube migration through the aortic hiatus in a dog.

A 9-year-old neutered male Golden Retriever was presented in cardiac tamponade. Initial stabilization involved pericardiocentesis, and through exclusion, a diagnosis of idiopathic pericardial effusion was made. The patient experienced multiple episodes of recurrent cardiac tamponade, and a subtotal pericardiectomy was ultimately performed. A thoracostomy tube was placed intraoperatively to aid in postoperative management and analgesia (intrapleural bupivacaine, 1.5 mg/kg q6hr). Approximately one hour after the third bupivacaine dose, the patient experienced acute onset of tachycardia, hypoxemia, and dull mentation. Repeat thoracic radiographs suggested migration of the thoracostomy tube through the aortic hiatus into the abdomen, followed by the suspicion of local anaesthetic systemic toxicity. The thoracostomy tube was subsequently removed and the patient was treated with intravenous intralipid emulsion. The patient survived without any long-term complications. This case highlights a previously unreported complication of presumptive thoracostomy tube migration into the abdomen of a dog via the aortic hiatus. It also describes peri-aortic administration of bupivacaine resulting in suspected local anaesthetic systemic toxicity. This underscores the importance of close patient monitoring following thoracostomy tube placement, thorough client education regarding potential complications, and repeat thoracic imaging in any patient with a thoracostomy tube that develops respiratory or cardiovascular compromise.