Regional cooling of the extracorporeal blood circuit: a novel anticoagulation approach for renal replacement therapy?

Krouzecky, Ales; Chvojka, J; Sýkora, Roman; Raděj, Jaroslav; Karvunidis, Thomas; Novák, Ivan; Růžička, J; Petrankova, Zuzana; Beneš, Jiří; Bolek, Lukáš; Matějovič, Martin

doi:10.1007/s00134-008-1271-9

Cited by 11 publications

(10 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, the beneficial effect of cooling on the life span of the extracorporeal circuit has been suggested [19]. In our series, the relatively short duration of the temperature variation period and the limited number of patients did not allow evaluation of the impact of modest hypothermic temperature on the potential reduction in extracorporeal clotting and we did not evaluate the consequences of the two regimen of temperature on blood coagulation tests.…”

Section: Discussionmentioning

confidence: 92%

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

et al. 2012

View full text Add to dashboard Cite

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.

show abstract

Section: Discussionmentioning

confidence: 92%

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

et al. 2012

View full text Add to dashboard Cite

show abstract

“…In conclusion, the data from this particular study, as well as from our previous experimental studies, show that hypothermal coagulopathy could also be a good servant and not only a bad master [8,9]. It was proven that cooling brought the blood into a complete noncoagulation status -a condition that can otherwise only be reached using chemical anticoagulants.…”

Section: Discussionmentioning

confidence: 72%

“…In our experimental study, this selective ECC cooling device was shown effective in preserving the circuit from clotting for several hours without the need of any anticoagulants. Although the efficiency of this cooling device was very good, the patency of the circuit was not retained for the planned 24-h period in all experiments [8,9]. One of the plausible explanations is that the decrease in blood temperature to 208C was not sufficient for some of animals -we can speculate that the response of an individual coagulation system to a certain temperature may not be always uniform.…”

Section: Introductionmentioning

confidence: 80%

“…Of course, the utility of obtaining such data might be questioned on the basis of the incompatibility of these extremely low body temperatures with life. Nevertheless, the results of our previous experimental studies, in which selective cooling of ECC was used as an alternative method of anticoagulation in renal replacement method (specifically continuous veno-venous hemofiltration), demonstrated a very promising potential for its clinical application [8,9]. However, by decreasing the temperature to 208C, the patency of the ECC could not be maintained for the planned 24 h in all of the animals [9] and the possibility of interindividual variability in blood coagulation in response to decreasing temperature was strongly considered.…”

Section: Discussionmentioning

confidence: 97%

See 1 more Smart Citation

Hypothermic anticoagulation

Růžička¹,

Štengl²,

Bolek³

et al. 2012

Blood Coagulation &Amp; Fibrinolysis

Self Cite

View full text Add to dashboard Cite

Selective incircuit blood cooling could be an effective anticoagulation strategy during hemodialysis. However, it is currently unknown what blood temperature would ensure sufficient anticoagulation. Similarly, no information exists about potential interindividual variability in response to graded hypothermia. Therefore, the aim of this study was to analyze effects of profound hypothermia on human coagulation. Furthermore, a mathematical relationship between blood temperatures and coagulation was sought to predict individual responses to blood cooling. It was designed as a laboratory study. Thromboelastography (TEG) measurements were taken at a temperature range of 38-12°C. To enable measurements below 20°C, the TEG device was placed into an air conditioned chamber allowing for setting of the temperatures over a wide range. The data were analyzed by regression analysis for pooled and individual measurements. Decreasing temperatures always led to a progressive reduction in blood coagulation by delaying the initiation of thrombus formation, as well as by decreasing the speed of its creation and growth. However, the response to cooling was not uniform and the interindividual variability exists. The relationship between blood temperature and coagulation is not linear but exponential (parameters R and K) and sigmoid (parameter α-angle). The lower the blood temperature, the more significant effect on blood coagulation decline. To predict an individual response of the coagulation system over a wide range of temperatures, a mathematical modeling can be used.

show abstract

“…Based on these observations, Krouzecky and colleagues now report on the deliberate cooling of blood in the extracorporeal CRRT circuit down to a temperature of 20°C as a novel technique for regional anticoagulation in an experimental porcine model [16]. This study randomized 12 anesthetized and ventilated pigs to 6 h of CRRT (neutral fluid balance, 20 mL/kg per h) with either regional blood cooling of the extracorporeal circuit (hypothermic circuit) or control (isothermic circuit).…”

mentioning

confidence: 99%

Cooling and reduced risk of clotting within the extracorporeal continuous renal replacement circuit

Bagshaw

Davenport

2008

Intensive Care Med

View full text Add to dashboard Cite

Clotting of the extracorporeal circuit, with a corresponding loss of blood in the circuit remains the Achilles heel of continuous renal replacement therapies (CRRT) [1]. Pre-mature circuit clotting results not only in a loss of efficacy of treatment, but also an increase in nursing work load, and higher financial costs due to circuit replacement [2, 3].Early circuit clotting may be the consequence of numerous factors including bio-incompatibility, inadequate vascular access, and critical illness in general (including thrombin generation, thrombocytosis, blood transfusions etc.) [4][5][6][7][8], along with specific CRRT circuitrelated factors such as stasis of blood flow [7, 9], hemoconcentration [7], and blood-air contact in air-detection chambers [7].Hypothermia has long been known to affect coagulation [10, 11] and therapeutic hypothermia may useful for reducing the risk of thrombus formation [12]. These observations are further supported by data showing a reduced pro-coagulant response to recombinant activated factor VII when administered in severe hypothermia [13][14][15].Based on these observations, Krouzecky and colleagues now report on the deliberate cooling of blood in the extracorporeal CRRT circuit down to a temperature of 20°C as a novel technique for regional anticoagulation in an experimental porcine model [16]. This study randomized 12 anesthetized and ventilated pigs to 6 h of CRRT (neutral fluid balance, 20 mL/kg per h) with either regional blood cooling of the extracorporeal circuit (hypothermic circuit) or control (isothermic circuit). No anticoagulation was used. Regional temperature manipulation in the extracorporeal circuit was achieved by use of a cooling exchange device at the blood inflow tract (set at 20°C) and a concomitant warming exchange device at the blood return tract (set at 38°C), both of which were monitored and controlled by a central computer. Numerous parameters related to circuit patency (i.e. time to clotting, alarm-trigger pump stopping, transmembrane pressure) and coagulation status [i.e. thrombin-antithrombin complexes (TAT), thromboelastography (TEG)] were determined before, during and following the prescribed therapy. The authors also investigated whether regional blood cooling altered systemic hemodynamics or induced significant hemolysis compared with isothermic controls. The key finding of the study was that regional blood cooling was associated with patency of all the extracorporeal circuits for the duration of applied CRRT, whereas five of the six isothermic circuits prematurely clotted. The clotting in the isothermic circuits was associated with a significant increase in transmembrane pressures and an increase in detectable extracorporeal TAT complexes, compared to the hypothermic circuits. In addition, blood sampling from the hypothermic circuits showed evidence of a significant delay in clotting time and a decrease clotting rate when assessed by standardized TEG, a functional assay of clot formation and lysis.

show abstract

Regional cooling of the extracorporeal blood circuit: a novel anticoagulation approach for renal replacement therapy?

Cited by 11 publications

References 19 publications

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

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

Hypothermic anticoagulation

Cooling and reduced risk of clotting within the extracorporeal continuous renal replacement circuit

Contact Info

Product

Resources

About