Pharmacologic prophylaxis of deep vein thrombosis and venous thromboembolism (VTE) is an important aspect of medical care, particularly in the inpatient setting. Low-molecular weight heparins, heparin, and fondaparinux are commonly used agents to prevent VTE, each of which has well established dosing regimens in patients with normal body mass index. Dosing of these medications in morbidly obese populations (BMI > 40 kg/m(2)) is not as clearly defined in guidelines. This article reviews published data to support specific dosing regimens and monitoring strategies of these agents in this population. The most validated parenteral agent to prevent VTE in morbidly obese hospitalized patients is enoxaparin, dosed at 40 mg subcutaneously (SC) twice daily. If unfractionated heparin is utilized for prophylaxis in morbidly obese patients, a dose of 7500 units SC three times daily should be considered. Monitoring of anti-factor Xa levels to guide prophylactic dosing is an option, although the utility of this lab test is limited, as target anti-Xa ranges for VTE prophylaxis have not been universally defined and trials have not shown a clear link between anti-factor Xa levels and bleeding or thrombotic events. Additional studies are needed to clearly define the most appropriate dosing strategies in patients with moderate obesity (BMI 35-40 mg/m(2)) and those with extreme obesity (BMI > 60 mg/m(2)).

The effect of obesity on the pharmacokinetics of enoxaparin is not clearly understood and traditional treatment doses in morbidly obese patients (body mass index [BMI] > 40 kg/m(2)) can lead to over anticoagulation. Our institution developed an inpatient protocol with reduced enoxaparin doses (0.75 mg/kg/dose based on actual body weight) for patients with a weight >200 kg or BMI > 40 kg/m(2). The primary objective was to determine if modified enoxaparin treatment doses would achieve therapeutic anti-Xa levels (goal range 0.6-1.0 IU/mL) in morbidly obese patients. Thirty-one patients were included in our study and had a median body weight of 138 kg (range 105-197) and a median BMI of 46.2 kg/m(2) (range 40.1-62). The initial peak anti-Xa levels were in therapeutic range in 15 of 31 patients (48 %) with an initial mean anti-Xa level of 0.92 IU/mL. Twenty-four patients (77 %) achieved therapeutic anti-Xa levels in goal range during their hospitalization, with a mean enoxaparin dose of 0.71 mg/kg. Bleeding and thrombotic events were minimal and all patients that achieved an anti-Xa level in goal range did so with a dose less than 1 mg/kg of enoxaparin.

Objectives: In congestive heart failure (CHF), men are younger, more likely to have reduced ejection fraction (HF-rEF), and to be diabetic compared to women. Despite this, sex differences in oxidative stress have yet to be explored in CHF. Methods: Data from 67 males and 63 females hospitalized for CHF were collected. Static oxidationreduction potential (sORP), a relative indicator of oxidative stress, and capacity ORP (icORP), a relative indicator of antioxidant capacity, were measured from plasma samples. We examined whether sex modified the relationship between ORP and hospital discharge disposition (poor outcome: death, hospice), along with other demographics, medications, and diagnostic parameters. Results: Males with poor outcomes had higher sORP and icORP values than females (P < 0.05). For those with a good outcome, there were no differences between the sexes (P > 0.05). Males were younger and more likely to have HF-rEF and diabetes. Controlling for these variables did not account for the sex differences in ORP measures. Regardless of sex, higher creatinine was related to higher sORP and icORP, while lower magnesium and potassium were related to higher sORP and icORP, respectively. Discussion: Increases in sORP during CHF are partially affected by sex and acute outcomes, but are also related to variables without sexual biases.