Use of Anthropometric Indices to Identify Appropriate Cuff Shapes for Blood Pressure Measurement: Normative Data for Adults

Accuracy of the KOROT P3 Accurate automated auscultatory blood pressure measuring device for professional use in people with extra-large arms

OBJECTIVE

To determine the accuracy of the KOROT P3 Accurate (previously InBody BPBIO480KV) monitor, an automated auscultatory blood pressure (BP) measuring device developed for professional use, in people with extra-large arms according to the ISO81060-2 2018 protocol.

METHODS

The KOROT P3 Accurate was tested in 37 subjects with upper-arm circumference ranging from >42 to 53 cm using a mercury sphygmomanometer coupled to a 20 × 40 cm tronco-conical cuff as the reference standard.

RESULTS

The mean BP difference between the device and the observers' reference measurements was 1.2 ± 2.0 mmHg for systolic BP and 1.0 ± 2.0 mmHg for diastolic BP. These data were in agreement with criterion 1 of the protocol standard requirements (≤5 ± 8 mmHg). Also criterion 2 was satisfied being the standard deviations ± 1.7 mmHg for systolic BP and ± 1.6 for diastolic BP, well below the maximum values required by the protocol (±6.84/6.87 mmHg). Scatterplots of device-reference systolic and diastolic BP differences showed similar accuracy across the range of participants' BP, arm circumference and upper-arm slant angle.

CONCLUSIONS

These data show that the KOROT P3 Accurate monitor satisfied the ISO 81060-2:2018 standard requirements in a special population of people with extra-large arms ranging from >42 to 53 cm.

Criteria for a suitable reference cuff for validation studies of blood pressure measuring devices in people with arm circumference between 43 and 50 cm

OBJECTIVE

Recommendations about the dimensions of the reference cuff for device validations in people with arm size >42 cm are still unavailable. The aim of this study was to identify the criteria for an appropriate reference cuff for validation studies in people with upper arm circumference between 43 and 50 cm.

METHODS

In 20 adults with upper arm circumference between 43 and 50 cm (X-large group), 34 subjects with arm circumference between 37 and 42 cm and 78 subjects with arm circumference <37 cm cylindrical and tronco-conical cuffs were compared. In all participants, the pressure transmitted to the arm under the two cuffs was measured using a paper-thin pressure sensor.

RESULTS

In the X-large group, all participants had an arm slant angle <86.0°. In this group, the difference between the pressure detected on the arm surface with the sensor using the cylindrical versus the tronco-conical cuff (13.5 mmHg) was larger than in the group with an arm circumference of 37-to 42 cm and the group with a circumference <37 cm (3.7 and 0.6 mmHg, respectively, P  < 0.001 versus both). In the whole sample, the between-cuff pressure difference was proportional to the conical shape of the arm ( P  < 0.001).

CONCLUSIONS

These data suggest that in people with arm size between 43 and 50 cm the reference cuff for validation studies should have a conical shape with an 84-85° slant angle. To comply with current guidelines, an 18.5 × 37.0 cm bladder should be used which would allow proper cuffing in the large majority of subjects.