Blood pressure (OSCE)

Taking a Blood Pressure

General

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  • No:
    • smoking or caffeine x 30 mins
    • constrictive clothing
  • Yes:
    • rest for ≥ 5 minutes
    • breathing normal and relaxed
  • During recording: no talking and patient’s legs uncrossed

Equipment

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  • cuff size
    • bladder width > 40 % of arm circumference
    • length > 80% of arm circumference

Positioning

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  • Level: devices and columns at eye level, patient’s arm held at heart level

Placement

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  • lower edge of cuff ~ 3 cm above elbow crease
  • bladder centered over brachial artery (palpate medial to biceps tendon)

Performance

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  • palpate radial pulse (note arrythmias)
  • inflate cuff to ~ 30 mm Hg above palpable pulse
  • drop the pressure by 2 mm Hg / second (prolonged filling will lead to venous congestion, making the sounds harder to hear)
  • repeat after ≥ 2 minutes of standing to assess for orthostatic hypotension (drop in 20/10)
  • for all patients on the first visit, take at least 2 readings separated by 2 minutes
    • if first 2 readings differ by > 5 mm Hg, another reading is indicated
    • Elevated readings should be confirmed on 3 readings

Pitfalls

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  • anxiety, pain
  • arrhythmias
  • wrong cuff size (too small overestimates, too large underestimates)
  • Isolated office hypertension ('white coat' hypertension) (up to 25%)
  • exercise

JNC-7 Classification

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(criteria for adults > 17 and not taking antihypertensives)

  • Optimal
  • Normal < 120 SBP and < 80 DBP
  • Prehypertension 120-139 SBP or 80-89 DBP
  • Hypertension Stage 1 140-159 SBP or 90-99 DBP
  • Hypertension Stage 2 >or=160 or >or=100


Other OSCE modules

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