Thermal Energy Balance During In Vitro Continuous Veno-Venous Hemofiltration

Transpulmonary thermodilution measurements are not affected by continuous veno-venous hemofiltration at high blood pump flow

“…2 Values of cardiac index measured before (TD on , by transpulmonary thermodilution), after blood pump stop (PC off , by pulse contour analysis and then TD off , by transpulmonary thermodilution), and after restarting the blood pump (TD on-last , by transpulmonary thermodilution) in a the 31 patients with a femoral dialysis catheter for whom the blood pump was set at 250 mL/min and b the 31 patients with a femoral dialysis catheter for whom the blood pump was set at 350 mL/min (250-350 vs. 80-150 mL/min, respectively). Moreover, we also set a high filtration flow (6,000 mL/h, i.e., 88 ± 28 mL/kg), which should maximize the thermal effect of CVVH on blood temperature [15,16]. However, our results are in discrepancy with the recently published study by Heise et al [4].…”

Nutritional and Metabolic Alterations during Continuous Renal Replacement Therapy

“…On the contrary, and especially during shock, overzealous hypothermia may be deleterious for myocardial function and should be carefully monitored especially also regarding clothing and platelet count [33,34]. Ideally, energy requirements should be measured by indirect calorimetry to more correctly match the amount of delivered calories to the patient's needs [35]. Indirect calorimetry, however, remains difficult to perform during CRRT because the CRRT-induced bicarbonate/CO 2 diversion renders the measurement unreliable [36].…”

Metabolic and Nutritional Aspects of Acute Renal Failure in Critically Ill Patients Requiring Continuous Renal Replacement Therapy

“…45,46 The primary mechanism by which CRRT causes hypothermia is heat loss. Heat is lost to the atmosphere, through blood tubing, the surface of the hemofilter, the effluent flow, and through the interaction of the patient's blood with room-temperature dialysate and replacement fluids.…”

“…Heat is lost to the atmosphere, through blood tubing, the surface of the hemofilter, the effluent flow, and through the interaction of the patient's blood with room-temperature dialysate and replacement fluids. 46 Hypothermia can mask one of the first signs of infection by inhibiting the patient's ability to mount a fever. Other side effects of hypothermia include the compromise of host immune defenses; increases in systemic vascular resistance and mean arterial pressure; and decreases in heart rate, cardiac output, and systemic oxygen delivery.…”

“…Other side effects of hypothermia include the compromise of host immune defenses; increases in systemic vascular resistance and mean arterial pressure; and decreases in heart rate, cardiac output, and systemic oxygen delivery. 46 Hypothermia has been linked with higher infection rates in critically ill patients. 45,47,48 Conversely, prevention of hypothermia in surgical patients has been found to decrease postoperative wound infections.…”