CNA Certification (Written Exam)Basic Nursing SkillsMedium
A nurse aide is preparing to measure a resident's blood pressure. Which of the following actions is most important for obtaining an accurate reading?
- AEnsuring the resident has eaten a full meal prior to the measurement.
- BTaking the measurement immediately after the resident has exercised.
- CHaving the resident cross their legs to promote relaxation.
- DUsing a blood pressure cuff that is the correct size for the resident's arm.
Show answer & explanationAnswer & explanation
Correct answer: D. Using a blood pressure cuff that is the correct size for the resident's arm.
An incorrectly sized blood pressure cuff is a common source of error in blood pressure measurement. A cuff that is too small will cause a falsely high reading, while a cuff that is too large will result in a falsely low reading.
Why the other options are wrong
- A. Eating a full meal does not directly affect blood pressure accuracy as much as cuff size; however, strenuous activity immediately after eating could.
- B. Exercise significantly increases blood pressure; the resident should rest for several minutes before measurement.
- C. Crossing legs can elevate blood pressure and lead to an inaccurate reading.
Accurate BP Cuff Sizing
The blood pressure cuff bladder length should be 80% of the arm circumference and the width should be 40% of the arm circumference.
- Too small cuff = falsely high reading
- Too large cuff = falsely low reading
- Ensure cuff is snug but not tight
- Position cuff 1 inch above antecubital fossa
Memory trick: Size the cuff right, or the numbers won't be bright!