Clinical Validation of The Combei BP 880 W
Condition: Hypertension
MeSH terms: Hypertension
Study type: Interventional

Summary: 
      Clinical validation of the wrist blood pressure measuring device Combei BP 880 W for home use
      according to "the Universal Standard for the validation of blood pressure measuring devices
      by the Association for the Advancement of Medical Instrumentation/European Society of
      Hypertension/International Organization for Standardization (AAMI/ESH/ISO)" in the general
      population.
    

Detailed description: 
      Members of the AAMI, ESH and ISO committees achieved a consensus on an optimal validation
      standard and agreed on a single protocol for the validation of BP measuring devices that will
      replace all previous ones.

      Therefore, the Association for the Advancement of Medical Instrumentation / European Society
      of Hypertension / International Organization for Standardization Universal Standard
      (AAMI/ESH/ISO 81060-2:2018) is now considered as the standard protocol for the validation of
      non-invasive blood pressure measuring device.

      This study aims to demonstrate that the Combei BP 880 W wrist device fulfills the
      requirements of the new protocol of clinical validation and its Amendment 1, 2020-01 for limb
      circumference distribution criteria.

      this is a monocentric, prospective, non-randomized, non-interventional, cross-study.

      Combei BP 880 W wrist device (Sphygmomanometer Under Test, SUT). The reference device is the
      mercury sphygmomanometer The primary objective of the study is to assess the accuracy of the
      automatic oscillometric BP measuring device at the wrist level, the Combei BP 880 W, in the
      general population, following AAMI/ESH/ISO 81060-2:2018 protocol and its Amendment 1, 2020-01
      for limb circumference distribution criteria.

      The Combei BP 880 W device will pass the test if:

        1. The differences of at least 255 individual paired determinations of the SUT and of the
           observers' readings with the reference sphygmomanometer for all subjects, calculated
           separately for systolic blood pressure and diastolic blood pressure, shall have the mean
           value of the differences, be within or equal to +/- 5.0mmHg and a standard deviation no
           greater than 8.0 mmHg.

        2. For the systolic blood pressure and diastolic blood pressure of at least 85 subjects,
           the standard deviation of the averaged paired determinations per subject of the SUT and
           of the observers' readings with the reference sphygmomanometer shall meet the criteria
           listed in Table 1 of AAMI/ESH/ISO 81060-2:2018.

      The secondary objective is to confirm the safety of use of this device, intended for home
      use.

      Inclusion criteria

        -  Patient older than 12 years;

        -  Patient who signed the informed consent form;

        -  Patient followed-up at site (in-patient or out-patient);

        -  Patient with wrist circumference between 12.5 and 21.5 cm*. *in accordance with the
           Indications For Use of the Combei BP 880 W device.

      Non-inclusion criteria

        -  Patient unable to give a consent or understand properly protocol information;

        -  Patient suffering from arrhythmia;

        -  Patient with poor quality of Korotkov sounds;

        -  Patient for whom K5 sounds are absent. The validation team will consist of three
           persons: two observers trained in accurate BP measurement and a supervisor.

             1. The reference sphygmomanometer is calibrated just before the beginning of the
                study.

             2. The observers are trained to the use of the SUT.

             3. In-patients or out-patients are included in the study after reading and signing the
                ICF.

             4. After inclusion, the patient is screened to verify that he/she satisfies the
                inclusion/non-inclusion criteria of the protocol. If not, the patient will be
                excluded from the study and no blood pressure measure will be performed on this
                patient.

             5. The patient is placed comfortably, and the reference sphygmomanometer is placed on
                his/her left upper arm, except if left upper arm is wounded. In this case, the
                reference sphygmomanometer is placed on his/her right upper arm.

             6. Measurements start with alternance between measurements with the reference
                sphygmomanometer and the SUT according to the same arm sequential BP measurements
                method.

             7. For each measurement with the reference sphygmomanometer, the two observers using
                mercury sphygmomanometers and a double-headed stethoscope, blinded from each
                other's result, and then by the supervisor using the tested device according to the
                manufacturer recommendations. The diastolic blood pressure should be measured at
                Korotkoff K5 sound. The agreement between the 2 observers will be checked all over
                the evaluation period by the supervisor to make sure that the difference between
                the two observers is no more than 4 mmHg for systolic and diastolic BP
                values.Otherwise, the measurement should be repeated. The intra individual BP
                variability for the reference BP measurements must be < 12 mmHg for SBP and < 8
                mmHg for DBP.

             8. The results are written down on a source document and then reported in the CRF. Any
                AE, ADE or device malfunction occurring during the protocol will be also documented
                and reported in the CRF. For this study, all source documents should be written in
                English language.

             9. At the end of the measurements, the patient participation to the study is over.

      Study procedures:

        1. Validation team and pre-study training

           The validation team will consist of three persons: two observers trained in accurate BP
           measurement and a supervisor.

           The reference sphygmomanometer is calibrated just before the beginning of the study.

           The observers are trained to the use of the SUT.

        2. Inclusion of the patients

           In-patients or out-patients of the investigational site are included in the study after
           reading and signing the ICF. After inclusion, the patient is screened to verify that
           he/she satisfies the inclusion/non-inclusion criteria of the protocol. If not, the
           patient will be excluded from the study and no blood pressure measure will be performed
           on this patient.

        3. Cuffs

           The cuffs used for reference auscultatory BP measurement will have an inflatable bladder
           length that covers 75-100% of the arm circumference of each patient and width that
           covers 37-50% of the arm circumference.

           Detailed description of cuffs used for reference BP measurement will be reported for
           each patient.

        4. Blood pressure measurements

      The validation will be performed according to the (AAMI/ESH/ISO) Universal Standard
      validation protocol described in detail elsewhere10. The patients will have their reference
      BP measured by the two observers using a mercury sphygmomanometer and a double-headed
      stethoscope, blinded from each other's result, and then by the supervisor using the tested
      devices. The agreement between the 2 observers will be checked all over the evaluation period
      by the supervisor to make sure that the difference between the two observers is no more than
      4 mmHg for systolic and diastolic BP values. Otherwise, the reference measurement should be
      repeated. The intra individual variability of the reference BP measurements must be < 12 mm
      Hg for SBP and < 8 mm Hg for DBP.

      The circumference of the patient's upper arm will be measured to ensure that the cuff-size
      being used is adequate for the subject. The upper arm midpoint is first determined by marking
      the arm posteriorly at a point halfway between the acromion and olecranon, measured while the
      arm is flexed 90 degrees at the elbow with the palm facing up. The subject's upper arm
      circumference shall be determined by measuring at the midpoint of the upper arm while the
      elbow is relaxed, and the arm is dangling freely to the side.

      The circumference of the patient's wrist will be measured to ensure that the circumference is
      within the acceptable range 12.5 - 21.5 cm for the Combei device, otherwise the subject will
      be excluded.

      Measurements made by the mercury sphygmomanometer, will be performed according to the "same
      arm, consecutive measurements" (Figure 1), on the left arm supported at heart level.

      Measurements by the Combei BP 880 W device will be performed at the wrist level of the same
      arm supported at the heart level, as recommended by the manufacturer with the following
      procedure.

        1. Ask the subject to relax for 5-10 min.

        2. make sure that the subject :

             -  is comfortably seated with legs uncrossed and feet flat on the floor,

             -  has the back, elbow and forearm supported,

             -  has the measurement site at the level of the left ventricle of the heart,

             -  and other conditions as recommended by the validation protocol and the device
                manual user.

      In total, nine consecutive BP measurements will be performed in each patient using the
      mercury sphygmomanometers (5 times) and the tested devices (4 times).

      All nine-sequential same-arm measurements will be recorded as shown in Table 2, starting with
      the standard mercury sphygmomanometer, followed by the device. A resting period of a minimum
      of 60 seconds shall be observed between the end of one measurement and the beginning of the
      following measurement.

      Table 2: Sequential measurements of BP recorded by the standard mercury sphygmomanometer and
      the tested device:

      R0 Entry BP, observers 1 and 2 each with the mercury standard T0 Device detection BP,
      supervisor R1 Observers 1 and 2 with mercury standard T1 Supervisor with the test instrument
      R2 Observers 1 and 2 with mercury standard T2 Supervisor with the test instrument R3
      Observers 1 and 2 with mercury standard T3 Supervisor with the test instrument R4 Observers 1
      and 2 with mercury standard

      The first auscultatory and the first device measurement represent the recruitment pressures
      (R0 and T0) are not used in the evaluation of the test device accuracy. Each of the reference
      BP measurements (R) is the average of the simultaneous readings of the two observers. For
      each subject, the device measurements T1, T2 and T3 will be compared to observer
      measurements. Each of the test device measurements is compared to the average of the previous
      and succeeding reference BP readings (T1 vs average of R1 and R2, T2 vs average of R2 and R3,
      T3 vs average of R3 and R4).

      At the end of the measurements, the patient participation to the study is over.

      The Statistical Analysis: Differences are calculated by subtracting the reference BP
      measurement from the test device measurement. The mean BP difference (SUT versus reference
      sphygmomanometer) and its standard deviation (SD) will be calculated for the analysis. The
      same criteria will be used for systolic blood pressure and diastolic blood pressure
      measurements. The statistical analysis will be performed according to the requirements of the
      AAMI/ESH/ISO standard 2018 and its Amendment 1, 2020-01 for limb circumference distribution
      criteria.
    

Intervention name(s): Measuring blood pressure
Intervention type(s): Device
Intervention description(s): Measuring blood pressure using electronic device and using a mercury sphygmomanometer
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Other
Keywords: validation; Blood pressure.; wrist device; electronic BP device; home Blood pressure