Question

The nursing instructor is teaching student nurses about the process of hemostasis after an injury. What does the nursing instructor include as the initial event in this process?

1. Platelets become sticky.
2. Plasma proteins convert to active forms.
3. The vessel spasms.
4. Von Willebrand's factor is activated.

Answer 1

Vascular spasm is the initial event in the process of hemostasis, where the vessel's smooth muscle contracts to limit blood flow after an injury, preceding platelet plug formation and coagulation.

Step-by-step explanation:

The nursing instructor includes vascular spasm as the initial event in the process of hemostasis after an injury. When a vessel is damaged, the vascular spasm occurs almost immediately, causing the smooth muscle in the walls of the vessel to contract and dramatically reduce the flow of blood. This is followed by the formation of a platelet plug and ultimately coagulation (blood clotting). The initial constriction of the vessel helps to reduce blood loss until the subsequent steps of hemostasis can occur. Von Willebrand factor does play a significant role in stabilizing the platelet plug, but it is involved in the second step, not initially.