Ambulatory Blood Pressure Monitoring

AFP 2011

  • Measures BP every 20-30 mins traditionally over 24 hours.
  • Safe, and not usually associated with complications,
  • They are quiet, lightweight and easy to wear,
  • Occasionally some bruising or petechiae develop

Indications

  • Suspected white coat hypertension
  • Suspected masked hypertension
  • Suspected night time hypertension ( the night non dipper)
  • Htn despite appropriate treatment
  • people with a high risk for cardiovascular events
  • Also good for;
    • Titrating antihypertensives
    • Borderline hypertension
    • Hypertension detected early in pregnancy
    • Suspected or confirmed Obstructive Sleep Apnoea
    • Syncope or other features suggesting orthostatic hypertension

Contraindication

  • Although not a contraindication, likely to be inaccurate with AF and other arrhythmias
  • Where does it fit;
    • More accurate than clinic BP’s- which commonly overestimate
    • Come in after bathing- you can’t get it wet.
    • Wear a top with loose sleeves
    • Do normal daily activities
    • Preferably a work day rather than a rest day
    • When the cuff starts going the person should stop moving and stop talking and keep the arm still and relaxed
    • Keep a brief diary to record timing of activities, sleep, taking of meds, any symptoms.

Results

  • 24 hr average<115/75, hypertension threshold 130/80
  • day time < 120/80 threshold 135/85
  • night <105/65 threshold 120/75.
  • Night timer average should be >10% less
  • BP Load = ( % of times above threshold should be < 20%.
  • If % successful readings > 85% then its an OK test