Objectives: The present study assessed the safety and efficacy of continuous venovenous hemodialysis (CVVHD) early after cardiac surgery.
Design: Retrospective database and medical record review.
Setting: University teaching hospital.
Participants: Forty-five dialysis-dependent patients who underwent cardiac surgery with cardiopulmonary bypass.
Interventions: CVVHD was begun postoperatively after confirmation of hemostasis, irrespective of circulatory status. In the last 5 patients, the ratio of extravascular lung water (EVLW) to intrathoracic blood volume (ITBV) was measured using a single-indicator thermodilution catheter and compared with patients of normal renal function undergoing cardiac surgery.
Measurements and main results: CVVHD was started at 4 hours after ICU admission. The maximum decrease in blood pressure within 60 minutes after initiation of CVVHD was 11 +/- 9 mmHg in the unstable hemodynamics group (defined as patients who required continuous intravenous adrenaline or intra-aortic balloon pump on admission to the ICU [n = 15]) and 7 +/- 8 mmHg in the stable hemodynamics group (n = 30, not significant). Circulatory status and oxygenation improved significantly 12 hours after CVVHD initiation in the unstable hemodynamics group. Blood volume from the chest tube did not increase after CVVHD. Early mortality (2.2%) was lower than that reported previously. The EVLW/ITBV ratio after ICU admission in dialysis-dependent patients was significantly higher than in patients with normal renal function.
Conclusions: Early CVVHD after cardiac surgery in dialysis-dependent patients was safe and effective. There was no associated increased postoperative bleeding or hemodynamic instability. Fluid removal improved respiratory status, particularly in patients requiring circulatory assistance, and overall early morality rates were lower that those previously published.