Successful resolution of a continuous pneumothorax using canine xeno-blood patch pleurodesis in a cat.

Case summary: An 11-year-old male neutered cat was referred to The Ohio State University's Veterinary Teaching Hospital after being diagnosed with pleural effusion by a referral veterinarian. After thoracocentesis, analysis of the effusion was consistent with chyle. Echocardiography, radiographs and bloodwork were used to diagnose hypertrophic cardiomyopathy phenotype and left-sided congestive heart failure, suspected to be secondary to uncontrolled hyperthyroidism. While initiating medical therapy, repeated thoracocenteses were required. A severe pneumothorax developed, necessitating placement of bilateral thoracostomy tubes. A thoracic CT scan did not reveal a cause for the pneumothorax; therefore, it was suspected to have occurred secondarily to an iatrogenic laceration of the parenchyma during thoracocentesis. An autologous blood patch pleurodesis was considered contraindicated so instead the cat was administered a blood patch using blood from a canine blood donor. The cat's respiratory status remained stable without additional intervention. At 30 h after blood patch pleurodesis, the thoracostomy tubes were removed and thoracic radiographs revealed near resolution of the pleural effusion and pneumothorax. The cat remained subclinical and was discharged from the hospital 48 h after the blood patch pleurodesis. Upon follow-up at 4 and 8 weeks after discharge, the cat was alive and had no complications or adverse reactions from the blood patch pleurodesis. Relevance and novel information: This case documents the first report of a xeno-blood patch pleurodesis performed in a cat using blood from a canine donor. The cat had a successful discharge from the hospital with no adverse reactions from the xeno-blood patch pleurodesis.