Chief Complaint
The patient was an 80 year old male who presented with shortness of breath, signs of right heart failure, and ascites.

History of Illness
He had a right heart catheterization and right ventricular biopsy to rule out restrictive cardiomyopathy and infiltrative diseases of the heart. He had equalization of pressures suggestive of pericardial constriction. The patient had been on high dose diuretics and had multiple abdominal paracenteses for drainage of ascitic fluid.

Peri-operative Details
He underwent a limited incision exploration of the pericardium because of the presence of a loculated pericardial effusion on echocardiography. This was then converted to a complete median sternotomy. There were dense pericardial adhesions and a radical stripping of the pericardial was performed from phrenic nerve to phrenic nerve. The posterior aspects of the myocardium were freed up to the inferior pulmonary veins. He did well immediately post-operatively, but had a low urine output despite a good cardiac output. Despite adequate blood pressure and cardiac output, he developed oliguria and his creatinine started to rise. He was extubated and was oxygenating well.

After the first 20 hours post-op, we ultrafiltered him with the system. We were able to take between 50 and 120 mL of fluid off every hour for 36 hours in the cardiac surgery ICU with a dramatic improvement in urinary output. His creatinine fell to baseline and he was discharged to the ward on the 4th post-operative day. He was then discharged home within a week after surgery.

Discussion
Peri-operative fluid overload is common in cardiac surgery patients. Many of them have been on diuretics for months if not years prior to seeking medical attention and surgical intervention. Post-operative renal failure carries a high mortality in cardiac surgery patients.

This patient illustrates the efficacy of ultrafiltration in actually promoting urine output and allowing incipient renal failure to actually regress. The mechanism of this might be debatable, but the presence of tissue edema and higher right sided filling pressures predispose to end-organ dysfunction in our experience. Our aggressive stance with      our system in this setting has helped rescue many a patient and their kidneys!

Case history courtesy of:

Associate Professor of Surgery, Director of Research