Predictors of initial nontherapeutic anticoagulation with. Weightbased enoxaparin dosing for venous thromboembolism. The determinants of activated partial thromboplastin time, relation of activated partial thromboplastin time to. See part b of weight based heparin order form initial infusion rate dependent on specific indication 10,000 5005,000250 250 380380 if at 6 hours, ptt is still greater than 120, hold heparin and call physician immediately for further orders.
Switching from weightbased loadcontinuous dosing to nonweight based protocols. It is not a substitute for appropriate clinical evaluation and does not supersede clinical judgment. Traditional regimens that normally begin with uhr are less likely to achieve this. Review the following related to unfractionated heparin ufh, low molecular weight heparins. Heparin infusion algorithms anticoagulation services. The extra vasculature present in obese patients appears to have minimal effect on the dosing of heparin. In july 2017, a new heparin protocol was implemented with changes for weight based dosing.
All hospitalized patients should be evaluated for both bleeding and vte risk within 24 hours of admission, upon transferring level of care, and periodically during the. How to solve a heparin protocol dosage calculation for. Description and evaluation of the implementation of a. Risk factors for requiring dosage change based on antixa, including. However, studies showed that weight based nomogram may be more effective than the standard care nomogram. Achievement of anticoagulation by using a weightbased heparin dosing protocol for obese and nonobese patients. Pharmacymanaged, weightbased heparin protocol american. Patients age 18 years or older receiving heparin therapy for greater than or equal to 24. Order as needed rebolus for subtherapeutic antixa, if warranted. Use best estimate of true weight if unable to weigh patient. Venous thromboembolism prophylaxis adult inpatient. Surgical patients who received an initial weight based ufh infusion achieved earlier therapeutic anticoagulation compared to underdosed ufh.
In 1996, a weightbased protocol for administration of heparin was implemented and assessed at the authors institution. Identify commonly used treatments, identified by standards of care, for patients. Ufh is a heterogeneous mixture of glycosaminoglycans that bind to antithrombin via a pentasaccharide, catalyzing the inactivation of thrombin and other clotting factors. In general, weight based nomograms are much more likely to achieve therapeutic levels within 48 hours. Start the infusion at 2mlshour 1,000 unitshour check aptt ratioaptt sec 4. Do not start in patients who have had tpa, for ischemic stroke, within 24 hours. Uw medicine heparin infusion ultra low intensity algorithm 2019. Backgroundintravenous unfractionated heparin infusion is often used to minimize the. Therapeutic dosing of unfractionated heparin adult.
It is important to note that the most critical factor in reducing the risk of recurrent thromboembolism is reaching a therapeutic ptt within 2448 hours. Neither nor any other party involved in the preparation or publication of this. Weightbased dosing of enoxaparin for vte prophylaxis in morbidly. Weight based heparin orders for deep venous thrombosis dvt and pulmonary embolism pe obtain ptt, inr, cbc prior to initiating heparin. At 2 affiliated community teaching hospitals, we compared the activated partial thromboplastin time aptt values in morbidly obese and nonmorbidly obese patients using a standardized nomogram and determined factors associated with achieving a supratherapeutic aptt value. Select the dose adjustment nomogram based on indication for ufh use 1.
Guidance for the practical management of the heparin. Ufh is a heterogeneous mixture of glycosaminoglycans that bind to antithrombin via a. Heparin is a potent anticoagulant medication, and a patient could become very ill if care providers make a mistake. Keywords anticoagulation, obesity, unfractionated heparin ufh, venous thromboembolism vte. Download citation evaluation of 2 weightbased protocols for administration of heparin in 1996, a weightbased protocol for administration of heparin was implemented and assessed at the. College lab week 1 objectives unit i perfusionrelated to alterations in perfusion weekly course objectives. After completion of a successful trial period for safety assessment of nomogram use and with continuing ethics committee approval, a prospective, singleblind, randomized, human clinical trial to examine the use of the nomogram was initiated. Based on these pharmacokinetic limitations, heparin therapy is usually. Article information, pdf download for enoxaparin dosing at extremes of weight. This article about unfractionated heparin ufh and lowmolecularweight heparin lmwh is part of the seventh american college of chest physicians conference on antithrombotic and thrombolytic therapy. This article describes the pharmacology of approved parenteral anticoagulants. Protocols create a simple, clear guideline for how to handle this medication and. Weightbased argatroban dosing nomogram for treatment of heparininduced thrombocytopenia article pdf available in annals of pharmacotherapy 431. Give dose by slow iv push, never to exceed 50 mg over a 10minute period references 1.
Perhaps the most striking aspect of our protocol is the relatively small ufh loading dose of 26 unitskg, compared with the 80unitskg dose promoted by the american college of. It has also been suggested that lowmolecularweight heparin may safely be used for 3 months in patients with venous thromboembolism. Heparin overview1 heparin is a glycosaminoglycan which inhibits the mechanism that induces the clotting of blood and the formation of stable fibrin. There is limited guidance on intravenous dosing of unfractionated heparin in obese patients.
A formal assessment revealed that, relative to traditional. To evaluate the difference in achieving goal activated partial thromboplastin time aptt within 24 hours utilizing the institutional heparin weight based protocol between obese and nonobese patients. Article information, pdf download for using antixa level for adjusting. Order standard heparin infusion with starting rate defaulted based on indication. Is monitoring antixa levels necessary in pregnant women on. The prescriber will initiate the heparin protocol by writing an order to begin. Unfractionated heparin infusion for treatment of venous. The molecular weight of heparin ranges from 5,000 to. Limitations of a standardized weightbased nomogram for. Comparison of two lowmolecular weight heparin dosing regimens for. Weight based heparin dosing for thromboembolic disease is associated with earlier anticoagulation in surgical patients. Weight based heparin dosing standard protocol modified. Removal of recommendations for heparin monitoring and dose titrations using ptt key practice recommendations 1. Kaplanmeier curves for the primary outcomes favored the weightbased nomogram p weightadjusted, unfractionated heparin may be suitable for inpatient and outpatient treatment of venous thromboembolism.
Optimal weight base for a weightbased heparin dosing protocol. Evaluation of current heparin weight based protocol in. Volume 12, issue 12, december 2014, pages 14161419. Vailoces, year1999 heparin is an anticoagulant widely used for the treatment and prevention of. Intravenous unfractionated heparin dosing in obese. Validation of a weightbased nomogram for the use of. Adult heparin drip protocol ventura county, california. Fractionated, low molecular weight heparin lmwh sc administration. View the article pdf and any associated supplements and figures for a period of 48 hours. Heparin infusion guidelines anticoagulation services. Unfractionated heparin dosing for venous thromboembolism. Evaluation of 2 weightbased protocols for administration.
Heparin dosing nomograms began to appear in the literature as early as 1985, 1 although it was not until 1993 that a weight based dosing protocol began to become the standard. Heparin dosing nomograms began to appear in the literature as early as 1985, 1 although it was not until 1993 that a weightbased dosing protocol began to become the standard. Switching from weightbased loadcontinuous dosing to non weight based protocols. A fixeddose protocol for heparin therapy, in which an initial loading dose and infusion rate were specified by physicians and partial thromboplastin times ptts were determined every 12 hours, was revised to determine dosing based on patient weight and diagnosis and to include more levels of dose adjustment and additional laboratory tests. Using antixa level for adjusting intravenous unfractionated heparin. Identify factors andor comorbidities affecting andor contributing to perfusion. Exemplars used this week are htn, cad, and acute mi 1. Weight based heparin dosing for thromboembolic disease is. Notify physician if platelet count is less than 100 k, hemoglobin drops by more than 1 gram from baseline, or other abnormal values. Although the authors show that therapeutic levels of low. American college of chest physicians evidencebased. The purpose of this study was to determine the efficacy and safety of a standard unfractionated heparin ufh protocol in obese patients based on total body weight tbw or adjusted body weight abw to reach two consecutive therapeutic antixa levels.
Prior to 2016, heparin dosing was based on standard care nomogram. Your patient is currently receiving an infusion based on 18unitskghour. Heparin protocols determine when heparin will be used. Adult heparin infusion protocol this protocol reflects current evidence based clinical practice. Pdf on nov 1, 1995, j hirsh and others published heparin. Fall 2016 heparin sliding scale example fall 20151111.
Heparin dosing calculator custom options available. Implement weightbased heparin protocols ihi institute. Evaluation of current heparin weight based protocol in obese patients purpose. Per the intravenous high intensity heparin nomogram for dvtpe, the infusion dose should be increased by 2 unitskghour. A heparin protocol is an established procedure for administering heparin, the anticoagulant used in a variety of applications for more than 12 million patients each year in the u. These include the indirect anticoagulants, unfractionated heparin ufh, lowmolecularweight heparins lmwhs, fondaparinux, and danaparoid, as well as the direct thrombin inhibitors hirudin, bivalirudin, and argatroban.
Watch out for tail chasing, the phenomenon in which the ptt is low, so the dose is raised, but then the ptt is high, so the dose is lowered to where it was before and then the ptt gets low again. Weightbased heparin protocol using antifactor xa monitoring. Comparison of lowmolecularweight heparin and warfarin. Evaluation of an unfractioned heparin pharmacy dosing protocol. Adult heparin drip protocol this protocol reflects current evidence based clinical practice. When a weight based heparin dosing strategy is selected, we suggest total body weight for calculating dose. Weightbased nomogram used for heparin therapy in nomogram patients. Iv heparin safety initiative standardizes protocols. The authors make no claims of the accuracy of the information contained herein. The weightbased heparin dosing nomogram compared with a. A revised protocol for heparin therapy, in which dosing was based on the patients weight and the pharmacy staff assumed responsibility for management of the. Weight based heparin dosing standard protocol modified protocol maintenance.
These changes warranted reevaluation of the standard and lowertarget protocols. If heparin interrupted for 2 hours, notify prescriber. Based on our study, heparin dosing based on actual body weight without a dose cap is safe and effective. Raschke and colleagues reported on their success with a weightbased ufh titration nomogram in 1993, setting the standard against which others would be compared. Develop a different weightbased protocol for patients receiving thrombolytics or g2b3a inhibitors, whose heparin doses will need to be lower. Confusion exists when dosing heparin using a weightbased nomogram in the obese population.