-
[show abstract]
[hide abstract]
ABSTRACT: Because of the inherent risks of intra-arterial blood pressure monitoring a new non-invasive device, Finapres, which measures blood pressure continuously in the finger, was evaluated in 14 hypertensive and one normotensive subject. Brachial intra-arterial and finger pressures were compared during a control period and a subsequent Valsalva manoeuvre. Visually, blood pressures measured by Finapres faithfully reproduced the intra-arterial recordings in all subjects. From each pressure signal beat to beat systolic, diastolic, and mean blood pressure values and their differences were obtained and the time course of the response and its characteristic features were analysed. During the control period the Finapres measurements were lower than intra-arterial systolic, mean, and diastolic pressures (mean(SD) 1(9.6), 9(6.8), and 4(6.1) mmHg respectively). During the response to the Valsalva manoeuvre the brachial-finger pressure differences showed limited deviation from those during the control period; median differences were at most 6 mmHg occurring late during the intrathoracic strain period and 7 mmHg during the post-release blood pressure overshoot. In general, the Finapres device reproduced intra-arterial patterns faithfully. This device appears to offer a reliable alternative to intra-arterial blood pressure monitoring.
Cardiovascular Research 07/1988; 22(6):390-7. · 6.06 Impact Factor
-
Nederlands tijdschrift voor geneeskunde 03/1988; 132(7):300-4.
-
[show abstract]
[hide abstract]
ABSTRACT: Intra-arterial blood pressure was compared with simultaneous auscultatory measurements in 37 subjects with a wide range of blood pressures and arm circumferences; six cuffs of various lengths and widths were used. Nineteen subjects had an arm circumference of 34 cm or more (mean 40 cm) and the other 18 were considered to be non-obese and had a mean arm circumference of 30 cm. With each larger cuff, in terms of bladder surface area, auscultatory blood pressure decreased a few mm relative to intra-arterial pressure both for systolic and for diastolic measurements. Apart from diastolic pressure measured with the two 12 cm wide cuffs (12 X 23 cm, 12 X 30 cm) in the obese group all other auscultatory measurements differed less than 5% from intra-arterial pressure, albeit with considerable variability among the subjects. The differences in error among measurements with the four largest cuffs in the obese group (13 X 30 cm, 14 X 30 cm, 14 X 38 cm, and a conical cuff) were clinically irrelevant, and there was even less to choose among all six cuffs in the non-obese subjects. These results suggest that auscultatory blood pressure may be measured with acceptable accuracy with a single long bladdered cuff both in subjects with large arms and in subjects with normal sized arms.
British medical journal (Clinical research ed.) 09/1987; 295(6594):354-5.
-
[show abstract]
[hide abstract]
ABSTRACT: The authors determined whether vasoconstriction alters the ability of a noninvasive method (Finapres) of continuously measuring arterial blood pressure in the finger to function accurately. They compared the response of the Finapres to blood pressures determined simultaneously by an oscillometric technique (Dinamap) in six anesthetized patients. Vasoconstriction was detected from a photoelectric plethysmogram, which was recorded continuously from an adjacent finger. Vasoconstriction was defined as a decrease in amplitude to less than half of its highest value in one and the same patient. From the 378 paired blood pressure readings obtained in this study, 51% took place in such a vasoconstricted state. The authors found that diastolic and mean blood pressures in the finger were, on the average, 9 mmHg below those in the upper arm and that the systolic pressure was 7 mmHg above that in the upper arm. The authors concluded that the Finapres keeps functioning well during peripheral vasoconstriction and is a recommendable method to monitor arterial blood pressure in the finger.
Anesthesiology 04/1985; 62(3):342-5. · 5.36 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Using noninvasive techniques only, the fall in mean pressure and the pulse amplification between brachial and finger arterial pressure were measured in six anaesthetised female subjects during surgery. Brachial pressure was measured every 2 min with an oscillometric technique. Finger pressure was measured continuously using an arterial volume clamp method. In addition changes in the degree of peripheral vasoconstriction were established on an adjacent finger with a photo reflection plethysmograph. On the average finger mean pressure is 10 mmHg below brachial pressure. The difference tends to decrease with increasing constriction. The change in the difference between full constriction and maximal dilatation is 8 mmHg. The average finger to brachial pulse amplitude ratio changes from 110% at maximal dilatation to 170% at full constriction. Finger systolic pressure overshoot is responsible for the pulse wave amplification. On the average it is + 7 mmHg and ranges between maximal dilatation and full constriction over 26 mmHg. The standard error deviation on the volume clamp method could be established at 5% for mean pressure, about equal to that of the oscillometric technique in the literature.
Cardiovascular Research 04/1985; 19(3):139-45. · 6.06 Impact Factor
