Coagulation monitoring correlation with heparin dose in pediatric extracorporeal life support.
Perfusion
; 32(8): 675-685, 2017 Nov.
Article
in En
| MEDLINE
| ID: mdl-28693359
ABSTRACT
OBJECTIVES:
Extracorporeal Life Support (ECLS) risks thrombotic and hemorrhagic complications. Optimal anti-coagulation monitoring is controversial. We compared coagulation tests evaluating the heparin effect in pediatric ECLS.METHODS:
A retrospective study of children (<18yrs) undergoing ECLS over 12 months in a tertiary pediatric intensive care unit (PICU). Variables included anti-Factor Xa activity (anti-Xa), activated partial thromboplastin time (aPTT), activated clotting time (ACT) and thromboelastogram (TEG®6s) parameters ratio and delta reaction (R) times (the ratio and difference, respectively, between R times in kaolin assays with and without heparinase). Test results were correlated with unfractionated heparin infusion rate (IU/kg/hr) at the time of sampling. Mean test results of each ECLS run were evaluated according to the presence/absence of complications.RESULTS:
Thirty-two ECLS runs (31 patients) generated 695 data-points for correlation. PICU mortality was 22% and the thrombotic complication rate was 66%. The proportion of variation in coagulation test results explained by heparin dose was 13.3% for anti-Xa, 11.9% for ratio R time, and 9.9% for delta R time, compared with <1% for ACT and aPTT. Incorporating individual variation, age and antithrombin activity in a model with heparin dose explained less than 50% of the variation in test results. Correlation varied according to age, day of ECLS run and between individuals, with parallel dose-response lines noted between patients. Significantly lower mean anti-Xa was observed in PICU non-survivors and runs with thrombosis.CONCLUSION:
Lower anti-Xa was observed in ECLS runs with complications. Although absolute results from anti-Xa and TEG6®s showed the best correlation with heparin dose, a large proportion of variation in results was unexplained by heparin, while dose response was similar between individuals. Population pharmacokinetic/pharmacodynamic modelling is required, as well as prospective trials to delineate the superior means of adjusting heparin therapy to prevent adverse clinical outcomes.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Blood Coagulation Tests
/
Heparin
/
Extracorporeal Membrane Oxygenation
Type of study:
Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
Limits:
Child, preschool
/
Female
/
Humans
/
Infant
/
Male
/
Newborn
Language:
En
Journal:
Perfusion
Journal subject:
CARDIOLOGIA
Year:
2017
Document type:
Article
Affiliation country:
Australia