24-hour Ambulatory BP

24 – Hour Ambulatory Blood Pressure 

When blood pressure readings are all over the place – as occurs in 15% of the population, we need a gold standard of BP measurement: the 24-Hour Ambulatory BP.

The 24-Hour Ambulatory BP is conducted with an automated BP Monitor, a “Walkman”- style electronic box  connected to a blood pressure cuff on the arm.

Automatic BP readings are taken at 20-minute intervals through the day and 40-minutes at night. Remarkably, most patients sleep quite well during the procedure.

A small number of patients  are unable to tolerate the device: it is best for them to abandon the procedure and make use of other evaluative technologies.


Here are some typical patterns of blood pressures as seen on  24 Hour Ambulatory BP

Normal BP: no action required

Mild Hypertension: intervention with lifestyle change or medical intervention (pills) is indicated


Ambulatory BP









White Coat Hypertension: observation-avoid casual BP readings. A Home BP monitor maybe helpful

Hypertension when ‘asleep’ – Nocturnal Hypertension:   implies sleep disturbance where a  Sleep Study may provide evidence of Sleep Apnoea