Using 24-hour Ambulatory Blood Pressure Monitoring to Determine if a Patient has High Blood Pressure

After going to the primary care provider, a patient is told that he has elevated blood pressure. The information comes as a surprise, because outside of the provider’s office, his blood pressure is usually lower. The primary places a referral to the kidney doctor with the following question: possible uncontrolled hypertension. Please evaluate further. Is there a convenient way we can determine if the blood pressure is high when we check it in the office but within the target range when we check it outside of the office? Stated another way, does the patient have isolated or white coat hypertension? There is indeed a way we can check! The tool used to evaluate for isolated clinic hypertension is called ambulatory blood pressure monitoring or ABPM. The following video explains the process in depth:

We will explain the most important facets of 24-hour-blood-pressure-monitoring using the figure below:

24 hour ambulatory blood pressure monitor sample report

Let’s see if John Doe, a 32-year-old male, has isolated clinic hypertension or true hypertension. Note the following backgrounder: John feels his blood pressure is “all over the place” at home. He doesn’t believe the readings at our office because he feels he gets nervous when there. John is only on two blood pressure pills. He is on lisinopril and hydrochlorothiazide at low doses, but he thinks he is on too many. We explained to him we may need additional therapy or higher doses of the medications that he is on to achieve the target. Let’s describe the readings in a narrative format:

The patient averaged 152/89 overall. That average blood pressure is high. More therapy is indicated.

The maximum systolic blood pressure was 190, and the minimum was 96.

The maximum diastolic blood pressure was 121, and the minimum was 52.

The average heart rate was 60.

You can see that the patient has high blood pressure. We need to account for the highs and the lows as well. Note the variability in the patient’s blood pressure readings, which correlates with the patient’s stated variable home blood pressure readings. You can see the importance of taking an average of the measurements. 24- hour ambulatory blood pressure monitoring helps provide an assessment of the burden of blood pressure. It helps the provider make sense of confusing, nonsensical readings and provide world-class care. We also offer the following additional value-added features as part of our comprehensive 24-hour ambulatory blood pressure monitoring assessment and treatment plan: We frequently correlate the patient’s home blood pressure cuff to our in-office machine to make sure the home readings are accurate. That will help blood pressure management in the future. We also offer, if indicated, a 24-hour ABPM recheck after we have made changes to see if we have improved the blood pressure. We want to confirm the patient is at goal.