Physical Therapy Assistant Practice Exam

What is the most important factor when selecting a blood pressure cuff size for a patient weighing 275 pounds?

1. Patient height

2. Extremity circumference

3. Patient weight

4. Blood pressure history

The correct answer is: Extremity circumference

When selecting a blood pressure cuff size, the most critical factor is the patient's extremity circumference. An appropriately sized cuff ensures accurate blood pressure reading; cuffs that are too small may yield erroneously high readings, whereas those that are too large can result in falsely low readings. The extremity circumference is essential as it directly influences the fit of the cuff on the arm or leg. When the cuff fits well, it can exert the correct amount of pressure to occlude the artery, leading to an accurate measurement when the pressure is released. While patient weight may provide some insight into expected cuff size, it is the circumference that ultimately dictates the proper fit. Other options, like patient height, may relate to general considerations in patient management, but they do not directly influence cuff accuracy as much as extremity circumference does. Blood pressure history can inform clinical decisions but does not affect the physical application of the cuff itself. Therefore, focusing on extremity circumference is paramount in ensuring precision in blood pressure measurement.