Hospital-acquired venous thromboembolism and prophylaxis in an integrated hospital delivery system

Without prophylaxis, hospital-acquired deep vein thrombosis (DVT) is approximately 10-40% among medical or general surgical patients and thromboprophylaxis for high-risk patients is currently recommended. This study analyse the risk factors associated with patients who developed a hospital-acquired venous thromboembolism (VTE) and what prior prophylaxis, if any, were given to these patients.

We identified 1 year of secondary VTE from seven metropolitan hospitals. A random sample was selected and reviewed retrospectively. Data abstracted included age, gender, VTE risk factors, surgeries, VTE prophylaxis, and anticoagulant dosing. Data analysis consisted of descriptive statistics.

A total of 118 patients with mean age 72.1 years (range 23-96) and 55.1% female. There were 60.2% DVT followed by 36.4% pulmonary embolism (PE); 7.6% had both DVT and PE diagnosed. About 73.7% of the study patients had two or more VTE risk factors. Five (4.2%) patients with hospital-acquired VTE had no risk factors. Overall, 88.5% of patients with risk factors received adequate VTE prophylaxis; 20.3% received heparin or enoxaparin, 56.6% received warfarin, and 11.5% received mechanical prophylaxis secondary to drug contraindications. Nine (8.0%) patients with risk factors and no contraindications, did not received any prophylaxis while four patients (3.5%) received inadequate prophylaxis. All-cause mortality was 13.6% (16/118).

Less than 5% of hospital-acquired VTE occurred in patients with no risk factors while 74% occurred in patients with two or more risk factors. In this seven-hospital study, 11.5% of hospital-acquired VTE with prior risk factors did not receive adequate prophylaxis. Educational in-services on the new CHEST guidelines should be provided within the hospitals to increase adherence to prophylaxis guidelines.