Heparin dosing

If patient is obese, utilize an adjusted body weight for heparin dosing... 

Unfractionated -loading dose of 80 mg/kg, followed by 18 mg/kg/hr adjust Heparin dose to maintain a therapeutic PTT... 

A heparin dose of 120 units/kg of body weight has been recommended for a patient undergoing certain type of surgery. How many mL of an injection containing 5000 heparin units/mL should be administered to a 220-lb patient ... 

Thrombocytopenia Thrombocytopenia has occurred in patients receiving heparin. The incidence of heparin-associated thrombocytopenia is higher with bovine than with porcine heparin. The severity also appears to be related to heparin dose. 

Anti-Xa activity has been used extensively for monitoring heparin administration to patients, and remains a necessary feature of the current heparin dose-adjustment paradigm [35]. Moreover, anti-Xa and anti-IIa activity have been used successfully in the exploration of patient covariates which may suggest regimen modifications for certain disease states [35, 36] and subpopulations [37, 38]. These parameters also appear to be sufficient to judge the in-vivo performance of such agents. One reason for the lack of predictability of anti-Xa and anti-IIa activity... 

Popma JJ, Prpic R, Lansky AJ, Piana R. Heparin dosing in patients undergoing coronary intervention. Am J Cardiol 1998 82 9P-24R... 

Matsuno et al. (1991) reports a method to induce thrombosis in the rat femoral artery by means of a photochemical reaction after injection of a fluorescent dye (rose Bengal, 10 mg/kg i.v.) and transillumination with a filtered xenon lamp (wave length 540 nm). Blood flow is monitored by a pulsed Doppler flow meter. Occlusion is achieved after approximately 5-6 min. Pretreatment with heparin dose-dependently prolongs the time required to interrupt the blood flow. The model also enables the study of thrombolytic mechanisms, which had been evaluated with t-PA. A comparative data for hirudin in various models was carried out by Just et al. (1991). 

Fig. 21 Cross-sectional view of a unit of Infusaid system, a vapor pressure-activated drug-delivery system, and daily heparin dose (mean S.E.) delivered to 25 dogs for 6 months and to 7 dogs for 12 months. (Adapted from Ref. " l)...

The volume of distribution of UFH is similar to blood volume (Vd = 60 mL/kg). The dose required to achieve a therapeutic anticoagulation response is correlated to weight. Obese patients do not have a proportional increase in blood volume relative to body weight. However, it is unclear if the patient s actual or adjusted body weight should be used when calcnlating initial heparin doses for obese patients. 

Raschke RA, Reilly BM, Guidry JR, et al. The weight-based heparin dosing nomogram compared with a standard care nomogram. Ann... 

EPIC m doubling of rates of major bleeding (14% cf. 7% placebo) and transfusions (standard heparin dose) increased rate of thrombocytopenia no increase in haemorrhagic stroke 6.5% incidence of antibody formation [199], [200]... 

If initiated within 30 min of last heparin dose, give 1 mg protamine per 100 U heparin... 

Leone-Bay A, Leipold H, Agarwal R, et al. The evolution of an oral heparin dosing solution. Drugs Future 1997 22 885-891. 

Menon V, Berkowitz SD, Antman EM, Fuchs RM, Hochman JS. New heparin dosing recommendations for patients with acute coronary syndromes. Am J Med. 2001 110 641-650. 

Heparin may prolong the prothrombin time, therefore a sufficient time interval should be allowed after the last heparin dose in a patient taking a coumarin to obtain a valid prothrombin time. 

Heparin may prolong the one-stage prothrombin time. The US manufae-turer notes that, if a valid prothrombin time is to be obtained in a patient starting warfarin or other coumarins, a period of a least 5 hours after the last intravenous heparin dose or 24 hours after the last subeutaneous dose should be left before measuring the prothrombin time. Note that it is usual clinical practice to start heparin and a coumarin anticoagulant at the same time. Further, it is clear that the concurrent use of warfarin and heparin will have an at least additive anticoagulant effect. 

The manufacturers of drotrecogin alfa contraindicate its use with therapeutic doses of heparin (15 units/kg/hour or more), but state that prophylactic heparin doses may be used concurrently. They also say that the risk benefit ratio of drotrecogin alfa should be carefully assessed in patients who have received thrombol i ics in the last 3 days, or oral anticoagulants, aspirin or platelet inhibitors within 7 days. 

In one study, patients who smoked tobacco had a shorter heparin half-life. However, smoking status is probably not important in predicting heparin dose. 

The hydrophilization of poly(ether sulfone) surfaces used for the production of ultrafiltration membranes for hemodialysis is of special interest Poly(ether sulfone) is a chemically inert and highly thermostable polymer showing a hydrophobic surface which leads to high fibrinogen adsorption and subsequent thromboembolization [111]. This effect is generally avoided by non-desirable heparin doses. The hydrophilization of poly(ether sulfone) surfaces by plasma-induced graftcopolymerization and the introduction of a hydrogel layer without... 

Independent double checks of i.v. heparin doses and infusions before dispensing... 

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