Supratherapeutic anti-factor Xa levels in patients receiving prophylactic doses of enoxaparin: A case series.
BACKGROUND
Enoxaparin prophylaxis prevents venous thromboembolism in surgical patients. Real time anti-Factor Xa monitoring for surgical patients on enoxaparin prophylaxis is increasingly common.


METHODS
We report on three cancer patients with therapeutic or supratherapeutic anti-Factor Xa levels while on prophylactic doses of enoxaparin after surgical procedures. In all cases, elevated anti-Factor Xa levels were the result of blood specimens being removed from a heparinized chemoport.


CONCLUSIONS
This case series highlights the importance of peripheral venipuncture or appropriate blood wasting from central access sites for anti-Factor Xa levels.


CONCLUSIONS
Inappropriately drawn anti-Factor Xa levels may contribute to prophylaxis interruption or unnecessary workup for renal or liver failure.
Division of Plastic Surgery, Division of Health Services Research, University of Utah, 30 North 1900 East, 3B400, Salt Lake City, UT 84132, United States. Electronic address: Christopher.Pannucci@hsc.utah.edu.
Christopher J
CJ
Pannucci
Division of Cardiothoracic Surgery, University of Utah, 30 North 1900 East, SOM 3C-127, Salt Lake City, UT 84132, United States.
Thomas K
TK
Varghese
Division of General Internal Medicine, Department of Internal Medicine, University of Utah, 30 North 1900 East, 5R218, Salt Lake City, UT 84132, United States.
Kencee K
KK
Graves
Department of Pharmacy Services, University of Utah, 50 North Medical Center Drive, A050, Salt Lake City, UT 84132, United States.
Ann Marie
AM
Prazak
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