HEMOFILTRATION IN A CARDIAC INTENSIVE-CARE UNIT - TIME FOR A RATIONALAPPROACH

The typical annual expenditure for patients requiring continuous hemof iltration (CHF) is high. To audit the benefit of this expensive treatm ent, the outcome of 48 consecutive patients (34 men, 14 women; mean ag e, 65 years) requiring hemofiltration for acute renal failure was anal yzed during a period of 24 months. The operations performed were 26 CA BG, 8 AVR, 3 AVR/MVR, 2 post infarction VSD repairs, and 1 thoracoabdo minal aneurysmectomy. Indications for hemofiltration were oliguria and fluid overload in 69%, uremia in 56%, acidosis in 33%, and hyperkemia in 13%. Twenty five patients (52%) died while in the hospital, and 10 more died within 9 months of discharge. Of the remaining 13 survivors , 6 (46%) were classified as III or IV according to the New York Heart Association classification system. The mean ITU and hospital stay per patient requiring CHF was 15.3 days and 25.4 days, respectively. Ther e were no statistically significant differences between patients who d id and did not survive in the hospital in age, pre-operative renal fun ction, ejection fraction, duration of cardiopulmonary bypass, or urine output before CHF. However, there were no survivors when the cardiac index was less than 1.7 L/m(2) and adrenalin requirement was more than 30 mu g/min before CHF (seven patients). These results suggest that t he short- and long-term outcome in patients requiring CHF after cardia c surgery is poor. Considering the large demand on resources, the use of CHF should be rationalized, particularly in patients with persisten t low cardiac output.