How do I get a patient with hypertension to take home blood pressure readings?

Home Blood Pressure Monitoring Protocol for Hypertensive Patients

To obtain reliable home blood pressure readings from your hypertensive patient, instruct them to purchase a validated upper-arm oscillometric device and take readings twice daily (morning and evening) for 7 days, following proper measurement technique. 1

Selecting an Appropriate Monitor

• Advise patients to purchase only validated upper-arm oscillometric devices
• Direct patients to check validation status on reliable websites:
  • British Hypertension Society (http://www.bhsoc.org/default.stm)
  • Dabl Educational website (http://www.dableducational.org) 2
• Wrist monitors are not recommended for routine clinical use 2
• Ensure proper cuff size by measuring the patient's upper arm circumference 2

Patient Education on Proper Measurement Technique

Preparation Before Measurement

• Empty bladder before taking readings
• Avoid smoking, caffeine, and exercise for at least 30 minutes before measurement
• Rest quietly for 5 minutes before taking readings 2, 1

Proper Positioning

• Sit with back supported and both feet flat on the floor
• Support arm on a flat surface with upper arm at heart level
• Position cuff on bare arm with mid-portion over the brachial artery
• Use non-dominant arm unless there is a marked difference between arms 2

Measurement Protocol

• Take readings twice daily:
  • Morning (before taking medications)
  • Evening (before dinner)
• Take 2-3 readings at each session, 1 minute apart
• Record all values without selection bias 2, 1, 3
• Avoid talking during measurements 2

Monitoring Schedule and Documentation

• Instruct patients to take readings for at least 7 consecutive days 1
• Recommend using devices with memory function to avoid selection bias 1
• Advise patients that individual high or low readings have little significance; the average is what matters 2
• Discourage taking readings at other times (e.g., when feeling stressed) 2

Validating the Monitor's Accuracy

When the patient brings their monitor to the clinic:

1. Have the patient sit at your desk with their monitor set up
2. Take five sequential same-arm BP readings with 30-second intervals:
   • First two readings (D1, D2): Patient uses their device
   • Third reading (M1): You use a mercury/calibrated sphygmomanometer
   • Fourth reading (D3): Patient uses their device
   • Fifth reading (M2): You use a mercury/calibrated sphygmomanometer
3. Compare the device and clinical readings to assess accuracy 2, 4
4. Repeat this validation annually 2

Common Pitfalls to Avoid

• Device validation: Many devices on the market have not been properly validated, which can lead to inaccurate readings 2, 5
• Improper technique: Failure to rest adequately or incorrect arm position can significantly affect readings 2
• Obsessional monitoring: Some patients may become anxious about readings, creating a vicious cycle of anxiety and elevated BP; discourage excessive monitoring in these cases 2
• Contraindications: Oscillometric devices may not work well in patients with atrial fibrillation or frequent ectopic beats 2, 1
• Selective reporting: Patients may only report "good" readings; emphasize the importance of recording all measurements 1

Home blood pressure monitoring provides valuable diagnostic information beyond office readings and helps identify white coat hypertension or masked hypertension, ultimately improving blood pressure control and reducing cardiovascular risk 3.