When ABPM is ordered, the client wears a portable blood pressure monitor for a 24-hour period and the blood pressure is measured and recorded at regular intervals.
CHEP (2004) recommends ABPM be considered when “white coat hypertension” is suspected in:
- Untreated clients with mild (140-159/90-99) to moderate (160-179/100-109) clinic-based hypertension, in the absence of target organ damage.
- Treated clients with:
a) Blood pressure that is not below target despite receiving appropriate therapy;
b) Symptoms suggestive of hypotension;
c) Fluctuating clinic-based pressure readings.
An average daytime APBM of 135/85 mmHg is considered to be the equivalent of an office-based measurement of 140/90 mmHg. A decrease in nocturnal blood pressure of less than 10% is associated with increased risk of cardiovascular events.
Clients with normal blood pressure on 24 hour monitoring have a prognosis similar to those with normal office blood pressure.