Objectives: To measure the effect of continuous venovenous hemofiltration with dialysis on cardiovascular stability in the critically ill patients and to assess the extraction of a number of hormones and catecholamines by continuous venovenous hemofiltration with dialysis.
Design: Prospective, clinical study.
Setting: Intensive care unit of a tertiary medical center.
Patients: Twenty critically ill patients with acute renal failure.
Interventions: Timed collections of serum and ultradiafiltrate in patients receiving continuous venovenous hemofiltration with dialysis, with measurements of their catecholamine and hormonal content and calculation of continuous venovenous hemofiltration with dialysis clearances and daily extractions. Correlation of changes in catecholamines with prospectively collected hemodynamic data during the first 24 hrs of continuous venovenous hemofiltration with dialysis therapy.
Measurements and main results: No significant changes in dopamine, epinephrine, and norepinephrine requirements or plasma concentrations were seen during the first 24 hrs of continuous venovenous hemofiltration with dialysis. Overall daily losses of catecholamines in the ultradiafiltrate were small (dopamine 404 micrograms; epinephrine 32 micrograms; norepinephrine 29 micrograms). Hemodynamic variables remained stable during this period of continuous venovenous hemofiltration with dialysis therapy. All studied hormones were detected in the ultradiafiltrate, but their mean daily extractions were very small (aldosterone 0.37 micrograms; parathyroid hormone 53.4 pmol; cortisol 4.8 mg; T4 and T3 [trace amounts]; thyroid-stimulating hormone 2.6 mU; testosterone [trace amounts]).
Conclusions: In critically ill patients with acute renal failure, continuous venovenous hemofiltration with dialysis results in minimal losses of catecholamines and is associated with cardiovascular stability. It causes only minor losses of several hormones. These losses are unlikely to be clinically important. Thus, blood purification achieved by continuous venovenous hemofiltration with dialysis does not produce significant catecholamine or hormonal losses and is associated with hemodynamic stability.