SATS 2009 Final Program - Scandinavian Association for Thoracic ...

P01:02
A COMPARISON OF ANTICOAGULANTS IN WHOLE BLOOD PLATELET IMPEDANCE AGGREGOMETRY
IN CABG PATIENTS
Thimour-Bergström Linda 1 , Roman-Emanuel Christine 1 , Jeppsson Anders 1
1) Sahlgrenska University hospital, Sweden
Objective
Impedance aggregometry is a new method to evaluate platelet function. Blood samples are collected in test tubes
with anticoagulants and analyzed in a point-of-care device. We investigated if blood samples from CABG patients
collected in tubes with hirudin and citrate gives comparable results.
Methods
Twenty CABG patients (mean age 66 +10 years) were included in a prospective observational study. 19/20 patients
were treated with aspirin and 10 were also treated with the ADP receptor blocker clopidogrel within seven days
before surgery. Platelet impedance aggregation (Multiplate®), with adenosine-diphosphate (ADP) and thrombin
receptor activated peptide 6 (TRAP) as activators, was measured after induction of anesthesia and at sternum
closure. Aggregation was expressed as area under the curve. Absolute difference, relative difference and correlation
coefficients (r) were calculated.
Results
In ADP-induced aggregation was the absolute difference between hirudin and citrate tubes -7±11 units (13±12 vs
5±4 units) and the relative difference -27±78%. There was no significant correlation between hirudin and citrate
tubes aggregation (r=0.25, p=0.11). In contrast, there was a strong correlation between hirudin and citrate tubes in
TRAP induced aggregation (r=0.84, p