Haemodilution-induced changes in coagulation and effects of haemostatic components under flow conditions.
Br J Anaesth
; 111(6): 1013-23, 2013 Dec.
Article
in En
| MEDLINE
| ID: mdl-23794670
ABSTRACT
BACKGROUND:
Blood flow patterns are important modifiers of platelet interactions with plasma coagulation factors. However, it is not feasible to evaluate rheological effects of haemodilution on coagulation using conventional coagulation testing.METHODS:
We evaluated thrombus formation with a microchip-based flow-chamber system using whole blood from 12 healthy volunteers (with/without 40% dilution with saline), and 15 cardiac patients [before/after cardiopulmonary bypass (CPB)] in parallel with thromboelastometry. The in vitro additions of von Willebrand factor (vWF, 1.5 U ml(-1)), prothrombin complex concentrate (PCC, 0.3 U ml(-1)), fibrinogen (2 g litre(-1)), or combined PCC (0.3 U ml(-1)) and fibrinogen (1 g litre(-1)) were examined. Recalcified whole-blood samples were perfused over the microchip coated with collagen and tissue thromboplastin at flow rates of 10 and 3 µl min(-1).RESULTS:
Dilution of whole blood led to delayed onset of thrombus formation (Ton), and thrombus growth (T80). Changes relative to baseline values were more extensive at 10 µl min(-1) (≥85% prolongation for Ton and T80) than at 3 µl min(-1) (≥40% prolongation for Ton and T80). Adding vWF accelerated thrombus formation only at 10 µl min(-1), while PCC increased thrombin generation in the thrombus at both flow rates. Fibrinogen increased mural thrombus formation at 3 µl min(-1). Decreased clot strength after dilution was restored by fibrinogen, but not by vWF or PCC on thromboelastometry. Additive effects of fibrinogen and PCC in post-CPB blood were demonstrated by both flow chamber and thromboelastometry.CONCLUSIONS:
Blood flow affects thrombus formation after haemodilution and subsequent haemostatic component interventions, with differential effects at low and high flow.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Blood Coagulation
/
Hemostatics
/
Hemodilution
Limits:
Adult
/
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
Br J Anaesth
Year:
2013
Document type:
Article
Affiliation country:
Japan