ABSTRACTS from 16th International COnference on ... - CRRT Online

Educational Objectives:
1) Discuss the interest of anticoagulation.
2) Describe use and regiment of heparin and LMWH.
3) Implication of Antithrombin (AT).
A17
Anticoagulation: Mechanisms and Techniques
Oliver Joannes-Boyau MD
10:00-11:30
Wednesday, February 15
Content Description:
Thrombosis and clotting filter stay a major concern during hemofiltration and the choice of the best anticoagulant
is always a terrible dilemma. Even if bad anticoagulation is not the primary reason of clotting problems it is
an obligatory part of the good operation of hemofiltration treatment.
Most of clotting circuit are the results of mechanical problems (50%) with the catheter, the site of catheter
insertion, the nursing of the patients and others. The anticoagulation is responsible of less than 40% of clotting
problems. However the misuse of anticoagulation is a capital point who must be to improve.
The unfractionated heparin (UFH) is the anticoagulant that is the most widely used in hemofiltration because it
is usable, low cost, measurable in blood and its possible complete inhibition by protamine. But there are two
major concern with UFH, bleeding problems (less than 10%) and heparin induced thrombocytopenia (HIT).
The regional anticoagulation has been presented in the past like the absolute solution, currently this way is near
completely abandoned except the citrate.
The low molecular weight heparin is still widely used in chronic hemodialysis but less and less used in acute
cases. It is more expensive than UFH, there is not antidote available, monitoring is difficult and there is 10% of
cross reaction for HIT with UFH.
The Antithrombin (AT) is the mandatory co-factor for heparin efficacy and its level activity is often reduced in
sepsis and in that case the efficacy of heparin decrease dramatically.
High doses of At has been used in the past to treat the sepsis, as APC does, but without beneficial effect. But
some articles have demonstrated an increase of mortality rate in case of AT deficiency and supplementation with
low doses of AT should be beneficial.
We have conducted a study to show if supplementation should be the good way to avoid the problem of early
thrombosis of the circuit. We have followed 28 patients in two centers to show the impact AT on filter lifespan
and the interest of AT supplementation in that case and we have also compared two different methods for supplementation
management : continuous infusion and bolus.
The critical level of AT activity seems to be 60% and below this point the filter lifespan is twice reduced. A
simple supplementation in AT increase filter longevity <strong>from</strong> 15 h to 33 h. The continuous infusion is a better
method than bolus one.
In summary, anticoagulation is not the only parameter to avoid the thrombosis problems during hemofiltration
but it is simple to improve it. Heparin stay the first anticoagulant in ICU but other ways are possible. AT level
may be a important concern during hemofiltration with heparin using.
Suggested Reading:
1. Davenport A: The coagulation system in the critically ill patient with acute renal failure and the effect of an extracorporeal circuit. Am
J Kidney Dis 1997, 30(5 Suppl 4):S20-27.
2. du Cheyron D, Bouchet B, Bruel C, Daubin C, Ramakers M, Charbonneau P: Antithrombin supplementation for anticoagulation during
continuous hemofiltration in critically ill patients with septic shock: a case-control study. Crit Care 2006, 10(2):R45.
3. Kutsogiannis DJ, Gibney RT, Stollery D, Gao J: Regional citrate versus systemic heparin anticoagulation for continuous renal replacement
in critically ill patients. Kidney Int 2005, 67(6):2361-2367.
4. Ranucci M: Antithrombin III. Key factor in extracorporeal circulation. Minerva Anestesiol 2002, 68(5):454-457.
5. Shulman RI, Singer M, Rock J: Continuous renal replacement therapy. Keeping the circuit open: lessons <strong>from</strong> the lab. Blood Purif
2002, 20(3):275-281.
6. Joannes-Boyau O, Lafargue M, Honoré P, Gauche B, Fleureau C, Roze H, Janvier G: Short Filter lifespan during Hemofiltration in
Sepsis : Antithrombin (AT) Supplementation Should be A Good Way To Sort Out This Problem. Blood Purif 2005, 23:149-174 (Abstract 145).
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