Related Experiment Videos
Thrombin activity on dissected and anastomosed human arteries
P C Johnson1, B V Heil, B Parva
1Department of Surgery, University of Pittsburgh, Pennsylvania 15261, USA.
The Journal of Surgical Research
|January 1, 1996
Summary
Thrombin activity on surgically repaired human arteries contributes to thrombosis. Standard heparin doses are ineffective, but higher local concentrations block this activity, suggesting a new therapeutic approach for microvascular surgery.
Area of Science:
- Vascular Surgery
- Thrombosis Research
- Biochemistry
Background:
- Anastomotic thrombosis is a significant complication in microvascular surgery.
- The precise mechanisms driving thrombosis at arterial anastomoses are not fully understood.
- Thrombin's role in initiating and propagating clots at surgical sites is a key area of investigation.
Purpose of the Study:
- To investigate the role of thrombin activity in anastomotic thrombosis.
- To quantify surface thrombin activity on human artery anastomoses and intact vessels.
- To assess the efficacy of heparin and recombinant hirudin in inhibiting this activity.
Main Methods:
- Utilized a human artery anastomosis model with placental artery segments.
- Measured surface thrombin activity by quantifying fibrinopeptide A (FPA) release.
- Assessed thrombin inhibition using varying concentrations of heparin and recombinant hirudin (r-hirudin).
Main Results:
- Intact and anastomosed vessels exhibited equivalent surface thrombin activity.
- Standard systemic heparin concentrations (0.3 U/ml) did not inhibit vessel-associated thrombin.
- High-concentration heparin (50 U/ml), used in irrigation, completely blocked thrombin activity.
- Recombinant hirudin effectively inhibited nearly all thrombin activity at both sites.
- Vessels demonstrated capacity to bind and express additional thrombin activity.
Conclusions:
- Surface-associated thrombin is present on dissected human vessels, both intact and anastomosed.
- Vessel-associated thrombin is resistant to standard systemic heparin but sensitive to high local concentrations.
- These findings suggest that localized high-dose heparin irrigation may mitigate anastomotic thrombosis in microvascular surgery.