Evaluation of digital blood pressure measured with the Omron F3 device as an index of brachial arterial pressure, under different thermal and hormonal conditions.
BACKGROUND
Devices that record from the finger have potential practical advantages for home monitoring of blood pressure. However, digital arterial pressure may vary substantially from that in the brachial artery, due to the influence of peripheral wave reflection.


OBJECTIVE
(1) To compare digital arterial pressure, as measured with the Omron F3 device, with brachial arterial pressure and (2) to determine the effect on digital pressure of changing local vascular resistance.


METHODS
The subjects were normotensive young adult non-smokers (12 males, 14 females). Pressures were recorded simultaneously from arm (using an Omron HEM-705CP) and finger with subjects seated and both recording sites at the level of the xiphisternum. Measurements were made at ambient temperatures of 19 degrees C and 30 degrees C; at rest, during brief contralateral hand cooling and after hand rewarming.


RESULTS
In many cases, resting finger values differed substantially from arm values; sometimes by 20 mm Hg or more. The extent of individual variations was not correlated with gender or temperature. However, group pressure differences between the sites were greater in females at ovulation than at menstruation and greater at 30 degrees C than at 19 degrees C. For all groups, pressure differences between sites were attenuated during hand cooling and restored by rewarming.


CONCLUSIONS
Finger blood pressure, as measured with the Omron F3, misestimates brachial blood pressure in a high proportion of normal subjects. This error is increased under circumstances associated with cutaneous vasodilation. The Omron F3 does not appear to be suitable for unsupervised home monitoring of blood pressure.
Tansey
E
E
Department of Physiology, Trinity College Dublin, Ireland. tanseye@tcd.ie
Bell
C
C
D000328:Adult; D001158:Arteries / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000295:instrumentation; D001916:Brachial Artery / Q000502:physiology*; D005260:Female; D005385:Fingers / Q000098:blood supply* / Q000502:physiology*; D006728:Hormones / Q000502:physiology*; D006801:Humans; D008297:Male; D012016:Reference Values; D012039:Regional Blood Flow / Q000502:physiology; D015203:Reproducibility of Results; D013696:Temperature; D014655:Vascular Resistance / Q000502:physiology
D006728:Hormones