Ambulatory blood pressure monitoring does not interfere with the haemodynamic effects of sleep.

Automatic or semi-automatic blood pressure (BP) monitoring is a widely used method for assessing 24-h BP profile. However, the ability to achieve this goal depends on several factors that have not yet been controlled. The present study examined the possibility that cuff inflations disturb the sleep of patients and prevent the nocturnal fall in BP. This issue was investigated in 10 hospitalized subjects in whom BP was recorded intra-arterially for 48 h using the Oxford method. During the first or the second 24 h BP was also monitored non-invasively (Squibb ICR portable device), the cuff inflations being performed at 15 min intervals during the day and at 30 min intervals during the night. The computer analysis of the two different 24-h intra-arterial tracings showed that the addition of automatic BP monitoring had not caused any alteration in the day and night intra-arterial BP and heart rate profiles. Thus, disturbances of the haemodynamic effects of sleep do not characterize 24-h automatic BP recording, at least when made with the device employed in the present study. This removes an important objection against the ability of this approach to evaluate the patients' BP profiles properly.