Wound Treatment Associate (WTA) Practice Exam

What typically causes pressure injuries?

1. Tissue swelling from hydration

2. Vessel dilation from increased blood flow

3. Compression caused by prolonged immobility and shear force

4. Rapid movement leading to skin friction

The correct answer is: Compression caused by prolonged immobility and shear force

Pressure injuries are primarily caused by compression from prolonged immobility and shear force. When a person remains in one position for an extended period, the weight of the body exerts pressure on specific areas, particularly over bony prominences. This sustained pressure can restrict blood flow to the tissues, leading to cellular damage and, eventually, tissue death. Shear forces, which occur when layers of skin and tissue move in different directions—such as when a person slides down in a chair—can further exacerbate this condition by stretching and tearing blood vessels in the skin. Understanding this process highlights the importance of repositioning patients regularly to relieve pressure and enhance circulation. Prevention strategies aim to reduce both pressure and shear forces, thereby protecting vulnerable skin and underlying tissues from injury.