How do you decide when, if ever, to defer pharmacologic venous thromboembolism prophylaxis for hospitalized patients?  

For the majority of patients who are not actively bleeding, I use pharmacological prophylaxis. I prefer heparin products, unless they have a history of HIT or religious preferences on porcine products. Even for patients planned for surgery, heparin can always be held or reversed. I prefer LMWH over ...