8.3 Blood Pressure Measurement (INACE Skill)

Blood Pressure as a Tested INACE Skill

Measuring and recording blood pressure (BP) is one of the 21 mandated INACE performance skills, and it is one of the hardest stations because a single missed critical element — a wrong step or a misread sound — fails the entire skill (the skills evaluation is critical-element pass/fail, not a percentage). Blood pressure is the force of blood pushing against the artery walls, reported as two numbers in millimeters of mercury (mmHg).

Understanding the Two Numbers

A reading is written systolic over diastolic, e.g., 118/76 mmHg, read "118 over 76."

Blood Pressure Categories

A hypertensive crisis (above 180/120) is a medical emergency — report it immediately.

Equipment

• Sphygmomanometer — the cuff with a pressure gauge (aneroid dial or digital).
• Stethoscope — used with a manual cuff to hear the Korotkoff sounds (the tapping made by blood flow).
• Correct cuff size — the inflatable bladder should wrap about 80% of the arm's circumference. Choosing the right cuff is the single biggest accuracy factor.

Manual Blood Pressure Procedure

Setup:

1. Wash hands, identify the resident, explain the procedure, provide privacy.
2. Have the resident rest at least 5 minutes; legs uncrossed, back supported.
3. Position the arm bare (roll sleeves; never measure over clothing) and supported at heart level.
4. Choose the correct cuff size and locate the brachial artery at the inner elbow (antecubital fossa).

Measuring: 5. Wrap the cuff 1 inch above the antecubital fossa with the arrow/marker over the brachial artery, snug but not tight. 6. Place the stethoscope earpieces forward; rest the diaphragm directly over the brachial artery (not tucked under the cuff). 7. Close the valve and inflate to ~180 mmHg (or 30 mmHg above the expected systolic). 8. Deflate slowly at 2-3 mmHg per second. 9. Systolic = the first clear tapping sound (first Korotkoff sound). 10. Diastolic = the point where the sounds disappear completely. 11. Fully deflate, remove the cuff, and record immediately.

If you must recheck the same arm, wait 1-2 minutes so trapped blood drains; rechecking too soon falsely raises the reading. Many programs accept readings within about ±4-8 mmHg of the examiner's value, so slow, careful deflation matters.

Common Errors and Their Effect

Arms to Avoid

Do NOT take blood pressure on an arm with an IV line (pressure can dislodge it), an AV fistula or graft for dialysis (can damage it), a mastectomy on that side (lymphedema risk), a fracture or injury, or paralysis from a stroke (inaccurate, and the limb may be fragile). Always check the care plan for the designated arm.

Orthostatic (Postural) Hypotension

Orthostatic hypotension is a drop in BP when a resident moves from lying to sitting or standing — defined as a fall of ≥20 mmHg systolic or ≥10 mmHg diastolic. It causes dizziness, lightheadedness, or fainting and raises fall risk. Have the resident dangle (sit on the bed edge) before standing, rise slowly, and report the change to the nurse.

Recognizing High and Low Readings

Know what the numbers mean for the resident in front of you. A persistently high blood pressure (hypertension) is often symptom-free, which is why it is called the "silent" condition — you cannot rely on how the resident feels, only on the measurement. Low blood pressure (hypotension) may show as dizziness, pale or clammy skin, weakness, or fainting, and raises fall risk during transfers. When you obtain an abnormal reading, stay calm, keep the resident safe and seated, report to the nurse, and avoid alarming the resident with the raw number until the nurse has reviewed it.

Tips for an Accurate Manual Reading

Manual blood pressure is a skill that improves with practice. Estimate the systolic first by palpating the radial pulse while inflating, then inflate 30 mmHg past where the pulse disappears — this prevents both over-inflating (uncomfortable) and missing the top number. Make sure the room is quiet so you can hear the soft Korotkoff sounds, position the gauge at eye level, and clean the stethoscope earpieces and cuff between residents for infection control. If you are ever unsure of a reading, do not guess — wait one to two minutes and repeat, or ask the nurse to verify.

Reporting an honest "I need to recheck" is always safer than charting a number you doubt.