BACKGROUND AND PURPOSE:

• The AHA has published guidance on how to properly obtain BP measurements, including having both of the patient’s feet on the floor, back supported and arm at heart level
• In routine care, there may be barriers to implementing these guidelines
• Alpert et al. (eClinicalMedicine, 2023) compared BP readings using AHA guidelines vs typical routine clinical care

METHODS:

• Prospective, randomized, 3-group cohort study
  • Modified cross-over design
• Participants
  • Arm circumference ≥18 cm and ≤42 cm
  • Did not have a renal dialysis shunt
  • No previous or current diagnosis of atrial fibrillation
• Exposures
  • Group A
    • BP readings taken on a fixed-height exam table followed by readings taken in an exam chair with adjustable positioning options
  • Group B
    • Readings taken in the reverse order, chair then table
  • Group C
    • Both sets of readings taken in the exam chair
• Study design
  • A rest period occurred before each set of readings
  • Group C was included for the purpose of obtaining an independent estimate of the order effect
• Primary outcome
  • The difference between the mean of three BP readings taken on the table and the mean of three readings taken in the chair

RESULTS:

• Group A: 48 participants | Group B: 49 participants | Group C: 53 participants
• The mean systolic/diastolic BP of readings taken on the table vs chair were significantly higher
  • Mean Difference increase 7.0/4.5 mm Hg P<0.0001
• In group C, the mean SBP/DBP of the first set of readings taken on the chair were 1.6/0.6 mmHg higher than for the second set of readings when including all 3 readings
  • There was no difference in SBP/DBP when including only the 2nd and 3rd set of readings

CONCLUSION:

• The positioning recommended by the AHA resulted in significantly lower BP readings than when patients were improperly positioned
• The authors state

This result demonstrates that when BPs are taken in the recommended position, the readings are lower and that simply following proper protocol could reduce the misdiagnosis of HTN for millions of patients, avoiding unnecessary medication or more intense follow-up

Learn More – Primary Sources:

Comparison of outcomes for routine versus American Heart Association-recommended technique for blood pressure measurement (CORRECT BP): a randomised cohort study