Measuring Blood Pressure (Manual and Automatic Methods)
Key Points
- Correct cuff size and arm positioning are required for valid blood-pressure readings.
- Manual and automatic methods both require premeasurement rest and proper technique.
- Unexpected values should be rechecked and correlated with symptoms before escalation.
Equipment
- Appropriately sized blood-pressure cuff
- Manual sphygmomanometer and stethoscope (for manual method)
- Automatic blood-pressure monitor (for automatic method)
- Hand hygiene supplies
Procedure Steps
- Complete routine pre-procedure actions: knock, identify resident, explain procedure, provide privacy, and perform hand hygiene.
- Confirm no contraindicated arm (for example fistula, recent mastectomy/lymph node dissection, or provider restriction).
- Seat or position patient with back supported, feet flat, legs uncrossed, and arm supported at heart level; allow at least 5 minutes of quiet rest.
- Select cuff with bladder width about 40 percent of arm circumference and bladder length about 80 to 100 percent.
- Apply cuff with bladder centered over brachial artery.
- Manual method: palpate/auscultate brachial artery, inflate cuff, then deflate at controlled rate while identifying systolic and diastolic values.
- Automatic method: start device and keep patient still and silent until reading completes.
- If reading is unexpectedly high/low, repeat measurement after brief rest and verify with alternate method when available.
- Restore patient comfort and environment safety (bed low/locked and call light in reach as applicable).
- Perform hand hygiene and document value, method, cuff size/site, and follow-up action.
Common Errors
- Using cuff that is too small → falsely high blood pressure.
- Unsupported arm or crossed legs → inaccurate elevation of readings.
- Measuring immediately after activity or conversation → unreliable baseline value.
- Failing to recheck abnormal reading → delayed recognition of true instability.
Related
- measuring-radial-pulse - Pulse and blood pressure trends should be interpreted together.
- vital-sign-indicators-of-physiologic-functioning-and-homeostasis - Links blood-pressure changes to integrated homeostasis assessment.