A nurse recently hired to the preoperative area learns that certain patients are at higher risk for venous thromboembolism (VTE). Which patients are considered to be at high risk? (Select all that apply.)

A. Morbidly obese patient: Obesity is a known risk factor for VTE due to several reasons. Morbidly obese individuals often have impaired mobility, which can lead to venous stasis (sluggish blood flow in the veins). Additionally, obesity is associated with inflammation and changes in blood clotting factors, increasing the risk of developing blood clots in the veins.

B. A woman who smokes and takes oral contraceptives or smokes: Both smoking and oral contraceptive use are independent risk factors for VTE. Smoking can cause damage to blood vessels and alter blood clotting mechanisms, while oral contraceptives can increase the risk of blood clots due to hormonal changes.

C. Wheelchair-bound patient: While being wheelchair-bound alone may not always indicate a high risk for VTE, immobility is a significant risk factor for developing blood clots. Prolonged periods of immobility can lead to blood stasis in the veins, making wheelchair-bound patients susceptible to VTE, especially if other risk factors are present.

D. Patient with a humerus fracture: A humerus fracture on its own may not necessarily increase the risk of VTE significantly. However, if the fracture requires immobilization or surgery, especially if it affects the lower extremities or leads to prolonged immobility, the risk of VTE can increase due to decreased blood flow and stasis.

E. Patient who underwent a prolonged surgical procedure: Prolonged surgical procedures often involve anesthesia, immobility during surgery, and postoperative immobilization, all of which can contribute to venous stasis and increase the risk of developing VTE. Additionally, the surgical trauma itself can trigger inflammatory responses and alterations in blood clotting factors, further elevating the risk of blood clots.