Benefits of an early cooling phase in continuous renal replacement therapy for ICU patients

Abstract

BackgroundLowering 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.MethodsThirty 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°C, the heating device was randomly set to 38°C (group A) and 36°C (group B) for 6 h. Then, the temperatures were switched to 36°C in group A and to 38°C in group B for another 6 h. Hemodynamic parameters and therapeutic interventions to control the hemodynamics were recorded.ResultsThere 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.ConclusionsIn patients undergoing CVVH, warming of the substitute over 36°C had no impact on body temperature. We showed that setting the fluid temperature at 36°C for a period of time early in the procedure is beneficial in terms of increased mean arterial pressure and decreased catecholamine infusion dosage.

Incidence of Adverse Events during Continuous Renal Replacement Therapy

“…Bellomo et al, found that the average pH and bicarbonate levels increased 0.075 and 4.5 mmol/l [26] , respectively, similar to our cohort in whom pH and bicarbonate increased 0.022 and 4 mmol/l, respectively. Robert et al reported that the mean temperature decreased by 1.05 ° C during CRRT (vs. 1.7 ° C in our report) [39] . Graham et al, described fewer catheter-related blood stream infections (0.03 vs. 1.2%/day), more pneumothoraces (2.4% vs. none), more hemothoraces (0.4% vs. none) and a similar arterial puncture rate (0.09 vs. 0.1%) [31] .…”

A case of hypothermia on CRRT

“…Ideally, the dialysate temperature should be tailored to the pre‐dialysis body temperature of the individual patient . In patients prone to hypotension on hemodialysis, lowering of dialysate temperature improves hemodynamic tolerance of HD …”

Nutritional and Metabolic Alterations during Continuous Renal Replacement Therapy

“…If the incorporated CRRT heating system fails to maintain the desired core temperature, external heating aiming at a temperature above 37°C (and sometimes even close to 42°C) must be utilized [32]. Of note, cooling may beneficially affect hemodynamics and outcome in ICU patients [33]. As such, CRRT has proven useful to quickly establish hypothermia in certain conditions (e.g.…”

“…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].…”

“…CRRT provokes a heat loss of approximately 1,000 kcal/day [33], which must be considered into the energy balance account. 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].…”