Abstract : ABSTRACT: BACKGROUND: Lowering the temperature setting in the heating device during continuous venovenous hemofiltration (CVVH) is an option. The purpose of this study was to determine the effects on body temperature and hemodynamic tolerance of two different temperature settings in the warming device in patients treated with CVVH. METHODS: Thirty patients (mean age: 66.5 years; mean SAPS 2: 55) were enrolled in a prospective crossover randomized study. After a baseline of 2 h at 38[DEGREE SIGN]C, the heating device was randomly set to 38[DEGREE SIGN]C (group A) and 36[DEGREE SIGN]C (group B) for 6 h. Then, the temperatures were switched to 36[DEGREE SIGN]C in group A and to 38[DEGREE SIGN]C in group B for another 6 h. Hemodynamic parameters and therapeutic interventions to control the hemodynamics were recorded. RESULTS: There was no significant change in body temperature in either group. During the first 6 h, group B patients showed significantly increased arterial pressure (p = 0.01) while the dosage of catecholamine was significantly decreased (p = 0.04). The number of patients who required fluid infusion or increase in catecholamine dosage was similar. During the second period of the study, hemodynamic parameters were unchanged in both groups. CONCLUSIONS: In patients undergoing CVVH, warming of the substitute over 36[DEGREE SIGN]C had no impact on body temperature. We showed that setting the fluid temperature at 36[DEGREE SIGN]C for a period of time early in the procedure is beneficial in terms of increased mean arterial pressure and decreased catecholamine infusion dosage.