What prophylactic medications should an adult patient in the hospital receive for Deep Vein Thrombosis (DVT) prophylaxis and Gastrointestinal (GI) prophylaxis?

Hospital Prophylaxis for Adult Inpatients

DVT Prophylaxis

For acutely ill hospitalized medical patients at increased risk of thrombosis, pharmacologic prophylaxis with LMWH, low-dose unfractionated heparin (LDUH), or fondaparinux should be administered throughout hospitalization. 1

Standard Prophylactic Regimens

Recommended first-line options include:

• Enoxaparin 40 mg subcutaneously once daily 1, 2
• Unfractionated heparin 5000 units subcutaneously every 8 hours (preferred in cancer patients and provides more consistent anticoagulant effect than twice-daily dosing) 1, 2, 3
• Dalteparin 5000 IU subcutaneously once daily 1, 2
• Fondaparinux 2.5 mg subcutaneously once daily 1

Special Population Adjustments

Renal impairment (CrCl <30 mL/min):

• Reduce enoxaparin to 30 mg subcutaneously once daily 2, 4
• Unfractionated heparin is preferred as it's primarily metabolized by the liver 2, 5
• Fondaparinux is contraindicated in severe renal insufficiency 5

Obesity (BMI >30 kg/m²):

• Consider enoxaparin 40 mg subcutaneously every 12 hours or weight-based dosing at 0.5 mg/kg every 12 hours 2, 5, 4

Cancer patients:

• Unfractionated heparin 5000 units subcutaneously every 8 hours is the preferred regimen 1, 2

Critically ill patients:

• LMWH or LDUH is recommended over no prophylaxis 1

Duration of Prophylaxis

Continue DVT prophylaxis until the patient is fully ambulatory or hospital discharge, with a minimum duration of 7-10 days for surgical patients. 1, 2, 4, 6

• Do not extend prophylaxis beyond the period of immobilization or acute hospital stay for most medical patients 1
• Selected high-risk patients may benefit from extended prophylaxis of 14-30 days post-discharge, particularly those with multiple VTE risk factors or elevated D-dimer 4

Contraindications and High Bleeding Risk

For patients who are actively bleeding or at high risk for major bleeding, anticoagulant thromboprophylaxis is contraindicated. 1

• Use mechanical prophylaxis with graduated compression stockings or intermittent pneumatic compression instead 1
• When bleeding risk decreases and VTE risk persists, substitute pharmacologic for mechanical prophylaxis 1

Do not use prophylaxis in low-risk hospitalized medical patients. 1

---

GI Prophylaxis (Stress Ulcer Prophylaxis)

While the provided evidence focuses primarily on DVT prophylaxis, limited guidance on GI prophylaxis is available from the FDA drug label for ranitidine. 7

For hospitalized patients requiring stress ulcer prophylaxis:

• Ranitidine 50 mg IV every 6-8 hours can be administered via intermittent bolus (diluted to ≤2.5 mg/mL, injected over 5 minutes) or intermittent infusion (diluted to ≤0.5 mg/mL, infused over 15-20 minutes) 7
• Continuous IV infusion at 6.25 mg/hour is an alternative for maintenance therapy 7

Dose adjustment for renal impairment (CrCl <50 mL/min):

• Reduce to 50 mg every 18-24 hours, with frequency potentially increased to every 12 hours if clinically required 7

---

Critical Clinical Pitfalls

Timing considerations:

• Do not administer anticoagulants too close to neuraxial anesthesia due to increased risk of spinal hematoma 2
• For surgical patients, enoxaparin should be started 2-4 hours preoperatively or 10-12 hours preoperatively 2

Monitoring:

• Routine anti-Xa monitoring is not required for prophylactic doses in most patients 2
• Monitor platelet counts every 2-3 days from day 4 to day 14 for patients at risk of heparin-induced thrombocytopenia (HIT), particularly with UFH where risk may be as high as 5% in orthopedic surgery patients 5

Common errors to avoid:

• Do not discontinue DVT prophylaxis prematurely before mobility is restored, even if the primary condition improves 4
• Do not use standard LMWH dosing in severe renal impairment without dose reduction 2, 4
• Do not forget to assess bleeding risk before initiating prophylaxis, particularly in patients with active gastroduodenal ulcer, recent bleeding, or platelet count <50 × 10⁹/L 4