Final answer:
A hematoma is a localized collection of blood outside of blood vessels caused by bleeding into the surrounding tissue.
Step-by-step explanation:
The patient has recently sustained an injury to the upper thigh. The irregular shaped purplish blue lesion that does not blanch with pressure and does not exhibit pulsatility is characteristic of a hematoma. A hematoma is a localized collection of blood outside of blood vessels caused by bleeding into the surrounding tissue. It appears as a purplish blue discoloration due to the presence of deoxygenated blood.
When blood vessels are damaged, blood leaks out and accumulates in the tissue, forming a hematoma. Since the blood does not have a way to return to the circulation, it remains trapped within the tissue. This causes the purplish blue discoloration and the non-blanchable nature of the lesion. Additionally, the absence of pulsatility suggests that the hematoma does not contain an arterial or venous component.
In the case of the upper thigh injury, the blood vessels in the area were likely damaged, leading to bleeding and the formation of the hematoma. The patient should be evaluated by a healthcare professional to determine the extent of the injury and any necessary treatment.