CClinicalTrials.gg
CompletedNCT02319174Updated Dec 19, 2018Results posted

Accuracy Assessment of an Automatic Blood Pressure Measurement Device in Pregnant Women

An interventional study of Sphygmo in Pre Eclampsia, sponsored by William Marsh Rice University. Completed at 1 site in United States. Open to female participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2018-12-19.

Sponsored by William Marsh Rice University · Not applicable, Interventional, and Device feasibility

Phase
Not applicable
Study type
Interventional
Enrollment
43
Allocation
Not applicable
Ages
18 Years and older
Sex
Female
01

Study summary

The purpose of the study is to help make a lower cost automatic blood pressure monitor device for diagnosis and monitoring of pre-eclampsia in pregnant women, where automatic blood pressure monitoring is limited or not available. The study will compare this low cost device to a commercially available system used for pre-eclamptic women in many United States hospitals that the investigators will be bringing to Malawi as a part of this study.

The team hopes to show that this lower cost blood pressure machine works well and can help women with pre-eclampsia. The study also aims to see if this machine is easy for the nurse to use.

70 pregnant women who are either at-risk or diagnosed with pre-eclampsia will be enrolled at University of Texas Health Science Center Houston. Patient arm circumference will be measured with measurement tape.

They will be seated upright in a comfortable chair with arm at heart level and an arm blood pressure cuff from either the automatic blood pressure monitor or a manual sphygmomanometer will be placed on the left arm.

The cuff will be inflated and then deflated until measurement concludes. Heart rate will be measured with tactile arterial palpation.The process will be repeated for a total of up to nine measurements, alternating between measurements with the automatic blood pressure monitor and the manual sphygmomanometer. There will be a waiting period of 45-60 seconds between each measurement.

The results of this study will help researchers understand the performance and usability of this device in Malawi and help decide if any design changes are needed.

Read the detailed description

The research team has developed an automatic blood pressure monitor to be used for the monitoring and diagnosis of pre-eclampsia in pregnant women, particularly in low-resource settings where current monitoring is limited. This study aims to evaluate the accuracy of the device's blood pressure measurements in pregnant and pre-eclamptic women. This device must be evaluated with the above described population because blood pressure measurement devices are known to perform differently in pregnant and pre-eclamptic women than in normal healthy adults.

This study will take place at the University of Texas Health Science Center (UTHSC) where up to 70 subjects will be recruited to participate during their regularly scheduled antenatal care checkups.

  1. The Patient arm circumference will be measured with measurement tape.
  2. The Patient will be seated upright in a comfortable chair with arm at heart level.
  3. An arm blood pressure cuff from either the automatic blood pressure monitor or a manual sphygmomanometer will be placed on the left arm of the patient over the brachial artery.
  4. Cuff will be inflated to \~200 mmHg and then deflated until measurement concludes.
  5. Heart rate will be measured with Tactile Arterial Palpation.
  6. Steps 3-4 will be repeated for a total of up to nine measurements, alternating between measurements with the automatic blood pressure monitor and the manual sphygmomanometer. There will be a waiting period of 45-60 seconds between each measurement.
02

Conditions studied

  • Pre Eclampsia
03

In context

Eclampsia

328 studies on the registry are indexed under Eclampsia; 48 are open to participants now.

This study's enrollment of 43 is below the median of 120 across 169 interventional studies indexed under Eclampsia.

Browse Eclampsia studies →

Lead sponsor

William Marsh Rice University is the lead sponsor of 17 studies on the registry; 7 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
Female
Accepts healthy volunteers
No

Inclusion criteria

  • Pregnant women receiving antenatal care at the UT OB/GYN clinic.
  • Over the age of 18

Exclusion criteria

Exclusion Criteria:

  • Women under the age of 18
  • Women unable to provide informed consent
05

Study design

Phase
Not applicable
Primary purpose
Device feasibility
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
43 participants (actual)

Study arms

  • Experimental
    Sphygmo

    All subjects will have blood pressure measured by both the research device (Sphygmo) and the commercially available device. All clinical decisions will be made using measurements from the commercially available device.

    Device: Sphygmo

Interventions

  • DeviceSphygmo

    A team of engineers from Rice University has recently developed Sphygmo, an ambulatory, low-cost blood pressure monitor for use in the diagnosis and management of pre-eclampsia in low-resource hospitals

06

What researchers measure

Primary outcomes

  1. Accuracy of Blood Pressure Readings by Sphygmo

    Mean difference of systolic and diastolic blood pressures between Sphygmo blood pressure measurements and measurements from the gold standard sphygmomanometer.

    Time frame: Blood pressure was measured an average of 9 times for each participant and the average of these measurements was recorded. Each measurement period lasted approximately 30-45 minutes

  2. Percent of Sphygmo Readings That Were Within 5mmHg, 10mmHg, and 15mmHg of the Readings by the Gold Standard Sphygmomanometer.

    The British Hypertension society defines a specific criteria for the accuracy of a sphygmomanometer. Devices are graded according to the cumulative percentage of readings that have an absolute difference between the more favorable observer's mercury sphygmomanometer readings and the test device of \< 5 mmHg, \< 10 mmHg, and \< 15 mmHg. A letter grade of "A" requires that over 60%, 85%, and 95% were achieved in the \< 5 mmHg, \< 10 mmHg, and \<15 mmHg categories, respectively. A letter grade of "B" requires that over 50%, 75%, and 90% were achieved in the \< 5 mmHg, \< 10 mmHg, and \<15 mmHg categories, respectively. The test device achieved a grade of (A/A) with the validation data from this study.

    Time frame: Blood pressure was measured an average of 9 times for each participant during their single measurement period, and the average of those measurements was recorded. Each measurement period lasted approximately 30-45 minutes

07

Results

Posted Dec 19, 2018

Participant flow

Participant flow — Overall Study
MilestoneSphygmo
Started43
Completed42
Not completed1

Outcome measures

PrimaryAccuracy of Blood Pressure Readings by Sphygmo

Mean difference of systolic and diastolic blood pressures between Sphygmo blood pressure measurements and measurements from the gold standard sphygmomanometer.

Time frame:
Blood pressure was measured an average of 9 times for each participant and the average of these measurements was recorded. Each measurement period lasted approximately 30-45 minutes
Reported as:
Mean · mmHg
Accuracy of Blood Pressure Readings by Sphygmo
mmHgSphygmoDinamap
Systolic Mean114.5 ± 10.9115.6 ± 12.5
Diastolic Mean65.7 ± 8.366.3 ± 10.6
PrimaryPercent of Sphygmo Readings That Were Within 5mmHg, 10mmHg, and 15mmHg of the Readings by the Gold Standard Sphygmomanometer.

The British Hypertension society defines a specific criteria for the accuracy of a sphygmomanometer. Devices are graded according to the cumulative percentage of readings that have an absolute difference between the more favorable observer's mercury sphygmomanometer readings and the test device of \< 5 mmHg, \< 10 mmHg, and \< 15 mmHg. A letter grade of "A" requires that over 60%, 85%, and 95% were achieved in the \< 5 mmHg, \< 10 mmHg, and \<15 mmHg categories, respectively. A letter grade of "B" requires that over 50%, 75%, and 90% were achieved in the \< 5 mmHg, \< 10 mmHg, and \<15 mmHg categories, respectively. The test device achieved a grade of (A/A) with the validation data from this study.

Time frame:
Blood pressure was measured an average of 9 times for each participant during their single measurement period, and the average of those measurements was recorded. Each measurement period lasted approximately 30-45 minutes
Reported as:
Number · percentage of measurements in range
Percent of Sphygmo Readings That Were Within 5mmHg, 10mmHg, and 15mmHg of the Readings by the Gold Standard Sphygmomanometer.
percentage of measurements in rangeSphygmo
Systolic Difference <5 mmHg67
Systolic Difference <10 mmHg85
Systolic Difference <15 mmHg98
Diastolic Difference <5 mmHg70
Diastolic Difference <10 mmHg89
Diastolic Difference <15 mmHg98

Adverse events

Collected over 1 year and 5 months.. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Sphygmo0/43 (0%)0/43 (0%)0/43 (0%)

Baseline characteristics

Age, Continuous
Age, Continuous(years)Sphygmo
Median29 (18 to 43)
Sex: Female, Male
Sex: Female, Male(Participants)Sphygmo
Female42
Male0
Region of Enrollment
Region of Enrollment(participants)Sphygmo
United States42
08

Study locations

1 site
  • University of Texas Health Science Center Houston
    Houston, Texas 77030, United States
09

References and documents

Publications

  • Natarajan P, Shennan AH, Penny J, Halligan AW, de Swiet M, Anthony J. Comparison of auscultatory and oscillometric automated blood pressure monitors in the setting of preeclampsia. Am J Obstet Gynecol. 1999 Nov;181(5 Pt 1):1203-10. doi: 10.1016/s0002-9378(99)70109-2. PubMed 10561646 ↗
  • Turner JA. Diagnosis and management of pre-eclampsia: an update. Int J Womens Health. 2010 Sep 30;2:327-37. doi: 10.2147/IJWH.S8550. PubMed 21151680 ↗
  • Dekker G, Sibai B. Primary, secondary, and tertiary prevention of pre-eclampsia. Lancet. 2001 Jan 20;357(9251):209-15. doi: 10.1016/S0140-6736(00)03599-6. PubMed 11213110 ↗
  • Magee LA, Abalos E, von Dadelszen P, Sibai B, Easterling T, Walkinshaw S; CHIPS Study Group. How to manage hypertension in pregnancy effectively. Br J Clin Pharmacol. 2011 Sep;72(3):394-401. doi: 10.1111/j.1365-2125.2011.04002.x. PubMed 21545480 ↗
  • De Greeff A, Ghosh D, Anthony J, Shennan A. Accuracy assessment of the Dinamap ProCare 400 in pregnancy and preeclampsia. Hypertens Pregnancy. 2010 Jan;29(2):198-205. doi: 10.3109/10641950902968650. PubMed 20367507 ↗
  • O'Brien E, Petrie J, Littler W, de Swiet M, Padfield PL, Altman DG, Bland M, Coats A, Atkins N. An outline of the revised British Hypertension Society protocol for the evaluation of blood pressure measuring devices. J Hypertens. 1993 Jun;11(6):677-9. doi: 10.1097/00004872-199306000-00013. No abstract available. PubMed 8397248 ↗
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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Dec 19, 2018, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT02319174
Lead sponsor
William Marsh Rice University
Collaborators
The University of Texas Health Science Center, Houston
Responsible party
Rebecca Richards-Kortum (Stanley C. Moore Professor of Bioengineering, William Marsh Rice University) — Principal investigator
First posted
Dec 18, 2014
Start date
Jun 2015
Primary completion
Jun 2015
Completion
Nov 4, 2016
Results posted
Dec 19, 2018
Last update
Dec 19, 2018

Study contacts

Rebecca R Kortum, PhD
principal investigator · William Marsh Rice University

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

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