When assessing a client's blood pressure, obtained via the unsupported left arm, which reading error would the nurse expect?

• A. False Low Reading
• B. False High Reading
• C. No Reading
• D. Accurate Reading

Answer: (B)

Position of the arm relative to the heart matters for accurate blood pressure. When the arm is not supported, it often hangs below heart level, and gravity adds hydrostatic pressure to the cuff. This makes the arterial pressure transmitted to the cuff appear higher than the true blood pressure, yielding a false high reading. If the arm were raised above heart level, you’d get a false low reading. To get an accurate measurement, keep the arm supported at heart level with proper cuff size and organization of the measurement.