Reliability of an ambulatory blood pressure recording device (Pressurometer®II)

In order to establish the performance reliability for the clinical use of the Pressurometer II (Del Mar Avionics, USA), I compared the blood pressure readings from the Pressurometer II with readings taken concurrently with a mercury sphygmomanometer in the supine, sitting, right lateral, left lateral and standing positions in 15 normotensive subjects. I also assessed the day to day reproducibility of the diurnal near-basal blood pressure in 9 normotensive subjects. Furthermore, diurnal variations of blood pressure and heart rate in 20 normotensive, hospitalized subjects were recorded in the absence of a physical activity limitation. Good correlations in systolic and diastolic blood pressure between the Pressurometer II and the mercury sphygmomanometer were obtained regardless of the position when taking on and off the Pressurometer II. Good reproducibility was demonstrated for whole-day blood pressure and heart rate measured with the Pressurometer II. Diastolic blood pressure in the right lateral position measured with the Pressurometer II was significantly but slightly higher than with the mercury sphygmomanometer. Second measurements indicated lower blood pressures at 9:00, 21:00 and 22:00 in comparison with the first measurements. A small diurnal variation in blood pressure with a lower level during sleep was observed in the subjects without physical activity limitation. These results indicate that the Pressurometer II is available for repeated evaluation of ambulatory blood pressure for periods of 24 hours.