Final answer:
The patient's symptoms of swollen feet and ankles, fatigue, shortness of breath, and spaced out feelings may be attributed to insufficient skeletal muscle pump function due to her obesity and lack of physical activity, which impairs venous return and can lead to these symptoms.
Step-by-step explanation:
An obese patient with symptoms such as swollen feet and ankles, fatigue, shortness of breath, and feelings of being "spaced out" may be experiencing issues related to skeletal muscle pump dysfunction. The skeletal muscle pump is a system that assists in the venous return of blood to the heart, especially from the lower extremities. If a person has reduced physical activity, such as the patient in question who is obese and works a stationary job as a cashier, the muscles are less active and therefore the pump does not function efficiently. This can lead to venous pooling and the symptoms described.
In the case of the patient, her occupation requires her to be on her feet all day; however, her lack of physical activity outside work and the discomfort while walking due to her weight suggest that her muscles are not contracting frequently or strongly enough to facilitate blood flow back to the heart. This could contribute to symptoms such as swollen feet and ankles, fatigue, and shortness of breath. Additionally, the feeling of being "spaced out" could be related to insufficient circulation affecting both physical and cognitive functions.