Related Experiment Videos
Evaluation of the activated whole blood clotting time (ACT) in vitro
Insights
Activated whole blood clotting time (ACT) monitoring is reliable for heparinization during heart surgery. While slightly shorter in heart patients, ACT shows a linear relationship with heparin levels and is unaffected by hemodilution or platelet changes.
Area of Science:
- Cardiovascular Medicine
- Hematology
- Surgical Monitoring
Background:
- Accurate heparin monitoring is crucial for patients undergoing open-heart surgery.
- Existing methods for assessing anticoagulation may have limitations in bedside settings.
Purpose of the Study:
- To evaluate the reliability and applicability of the activated whole blood clotting time (ACT) as a bedside monitoring tool for heparinization.
- To establish the relationship between ACT and heparin concentrations in patients undergoing cardiac surgery.
Main Methods:
- In vitro analysis of activated whole blood clotting time (ACT) using blood samples from healthy individuals and cardiac surgery patients.
- Assessing the influence of varying heparin concentrations, hemodilution, and platelet depletion on ACT values.
- Correlation analysis between ACT measurements and heparin levels.
Main Results:
- Activated whole blood clotting time (ACT) exhibited a normal distribution in healthy individuals with a mean of 135 seconds.
- Patients with heart disease showed a slightly shorter average ACT compared to normal individuals.
- A significant linear correlation was observed between ACT and heparin concentrations.
- Hemodilution and platelet depletion did not substantially impact ACT measurements.
Conclusions:
- Activated whole blood clotting time (ACT) is a dependable and straightforward bedside method for monitoring heparinization.
- The technique is validated for use in patients requiring anticoagulation during open-heart surgery, provided clean venipuncture is employed.
Abstract:
The activated whole blood clotting time (ACT) was analyzed in vitro using blood samples from normal individuals and from patients with heart disease, scheduled for open heart surgery. The ACT was found to be normally distributed in a group of normal individuals with a mean of 135 sec. In patients with heart diseases, the average ACT was slightly shorter than in normal individuals. A linear relationship between ACT and heparin concentrations was established. Haemodilution and depletion of platelets did not significantly influence the ACT. When a clean venipuncture with disposable needles is used, ACT is a reliable, uncomplicated bedside technique by which heparinisation can be monitored.