Related Experiment Videos
[Monitoring heparin therapy by thrombin time and activated partial thromboplastin time--a comparison]
Schweizerische Medizinische Wochenschrift
|November 29, 1986
Summary
Activated partial thromboplastin time (APTT) may overestimate heparin levels in critically ill patients. Thrombin clotting time (TT) offers a more reliable measure for heparin monitoring in severe infectious disease, liver disease, or myocardial infarction.
Area of Science:
- Clinical Chemistry
- Hematology
- Pharmacology
Background:
- Heparin therapy requires accurate plasma concentration monitoring.
- Activated partial thromboplastin time (APTT) and thrombin clotting time (TT) are common laboratory tests for this purpose.
- Discrepancies between APTT and TT may arise in critically ill patients.
Purpose of the Study:
- To compare the accuracy of APTT and TT in monitoring heparin therapy.
- To identify patient populations where APTT may overestimate heparin concentrations.
Main Methods:
- Analysis of 106 plasma samples from patients undergoing heparin therapy.
- Comparison of results obtained from APTT and TT assays.
- Categorization of patients into groups based on the discrepancy between APTT and TT results.
Main Results:
- Critically ill patients (severe infectious disease, liver disease, extensive myocardial infarction) showed markedly higher heparin concentrations by APTT compared to TT.
- Patients with less severe conditions exhibited smaller discrepancies between APTT and TT.
- Non-heparin related factors were implicated in APTT's overestimation of heparin in critically ill patients.
Conclusions:
- APTT is not recommended for laboratory monitoring of heparin therapy in patients with severe infectious disease, liver disease, or extensive tissue necrosis (myocardial infarction).
- TT may provide a more reliable assessment of heparin levels in these patient groups.