Wireless fetal heart rate monitoring in inpatient full-term pregnant women: testing functionality and acceptability

Abstract

We tested functionality and acceptability of a wireless fetal monitoring prototype technology in pregnant women in an inpatient labor unit in the United States. Women with full-term singleton pregnancies and no evidence of active labor were asked to wear the prototype technology for 30 minutes. We assessed functionality by evaluating the ability to successfully monitor the fetal heartbeat for 30 minutes, transmit this data to Cloud storage and view the data on a web portal. Three obstetricians also rated fetal cardiotocographs on ease of readability. We assessed acceptability by administering closed and open-ended questions on perceived utility and likeability to pregnant women and clinicians interacting with the prototype technology. Thirty-two women were enrolled, 28 of whom (87.5%) successfully completed 30 minutes of fetal monitoring including transmission of cardiotocographs to the web portal. Four sessions though completed, were not successfully uploaded to the Cloud storage. Six non-study clinicians interacted with the prototype technology. The primary technical problem observed was a delay in data transmission between the prototype and the web portal, which ranged from 2 to 209 minutes. Delays were ascribed to Wi-Fi connectivity problems. Recorded cardiotocographs received a mean score of 4.2/5 (± 1.0) on ease of readability with an interclass correlation of 0.81(95%CI 0.45, 0.96). Both pregnant women and clinicians found the prototype technology likable (81.3% and 66.7% respectively), useful (96.9% and 66.7% respectively), and would either use it again or recommend its use to another pregnant woman (77.4% and 66.7% respectively). In this pilot study we found that this wireless fetal monitoring prototype technology has potential for use in a United States inpatient setting but would benefit from some technology changes. We found it to be acceptable to both pregnant women and clinicians. Further research is needed to assess feasibility of using this technology in busy inpatient settings.

Conflict of interest statement

Competing Interests: The authors of this manuscript have the following competing interests: co-author Jessica Haberer is a PLOS ONE Editorial Board member. This does not alter their adherence to PLOS ONE Editorial policies and criteria.

Figures

Fig 1. Wireless fetal monitoring prototype technology.

Components illustrated include (from left to right): 1. Data gateway device (Android tablet) with fetal cardiotocograph output demonstrated on monitor. 2. Doppler monitor for assessing fetal heart beat attached with elastic strap to a model of a pregnant woman.

Fig 2. Components of the wireless fetal monitoring prototype technology [7] (from left to right):

1. Wireless Sensing Hardware represents the prototype technology as created by West Health Institute. This is capable of sensing fetal heartbeat and uterine contractions, digitizing the single, and transmitting this signal via Bluetooth technology. 2. The Gateway represents a smartphone or tablet device with operating system 4.2.1 or greater and capable of running a customized software application. The application on the device allows visualization of the fetal cardiotocograph in real-time, and submission of this data via the Internet to a web portal and user interface.

Fig 3. Illustration of steps required for submission of a completed monitoring session.

In panel A, step 1 involves hitting the save button. In panel B, step 2 requires the user to confirm completion of the session. In panel C, the user must then hit “Submit “to complete step 3. In panel D, the screen with “Uploading Data” confirms submission is complete. In our experience step 3 was the most often missed step, as there is no prompt to hit the “Submit” button at this stage. This miss-step was correctable with further training and practice with the application.

Fig 4. Examples of cardiotocographs obtained with the prototype technology.

Panels A and B show (from top to bottom) fetal heart rate, maternal heart rate, uterine tone and contractions. The fetal cardiotocograph in panel A received a mean score of 5 on readability. The fetal heart rate depicted is continuous with no breaks and loss of contact allowing easy interpretation of the baseline heart rate and to assess for increases and decreases in heart rate. Panel B shows a fetal cardiotocograph that received a mean score of 1.7. Here lack of a continuous heart rate tracing prevents interpretation of the fetal heart rate at all times. For example it is hard to distinguish if gaps in the tracing represent decreases, increases or no change in the baseline fetal heart rate.