Fetal Heart Rate and Amniotic Fluid Volume Measurements with a Home Ultrasound Device

Abstract

Objective

Pulsenmore ES is a self-scanning ultrasound (US) system for remote fetal assessment. It comprises a handheld transducer that serves as a smartphone cradle coupled with an application and clinician's web-viewer dashboard. Recently, a novel capability was added to the system allowing offline fetal heart rate (FHR) and maximal vertical pocket (MVP) measurements. The aim of this study was to evaluate these tools for usability and accuracy.

Study Design

A prospective, non-randomized, non-blinded clinical study design was used. Pulsenmore ES scans were obtained by non-professional laypersons in app-guided (AG) mode (user follows video tutorials in the application) or clinician-guided (CG) mode (user is guided by a health care professional in a real-time telemedicine visit). The scans were stored on a cloud for later interpretation by a health care professional. Each self-scan was immediately followed by a standard US scan performed by a clinician. The asynchronous FHR and MVP measurements made on the AG and CG scans through the designated dashboard were analyzed and compared with the real-time, in-clinic (INC) measurements.

Results

The cohort included 28 women. Rates of successful utilization of the Pulsenmore tool for measurement of FHR were 84.7 ± 11.24% of scans made in AG mode and 96.3 ± 6.35% of scans made in CG mode. Corresponding values for MVP were 91.7 ± 2.31% and 95.0 ± 1.73%. FHR accuracy (difference from INC values) was 10.8 ± 7.5 beats per minute (bpm; 7.2%) in AG mode and 5.8 ± 5.1 bpm (4%) in CG mode. MVP accuracy was 1.3 ± 1.4 cm (22%) and 0.9 ± 0.8 cm (14%), respectively. Sensitivity (87.5% and 100% in AG and CG modes, respectively) and specificity (95% and 95.5% in AG and CG modes, respectively) were established for MVP.

Conclusion

FHR and MVP measurements obtained from scans captured by the self-operated Pulsenmore ES ultrasound platform are highly accurate and reliable for clinical use relative to standard INC measurements.

Key Points

• Pulsenmore ES is a self-scanning US system for remote fetal assessment.

• FHR and MVP can be accurately and remotely measured from home.

• Home US can play a critical role in remote antenatal surveillance.

Keywords

ultrasound - home - mobile - fetal heart rate - amniotic fluid volume - maximal vertical pocket

Publication History

Received: 07 September 2024

Accepted: 14 November 2024

Accepted Manuscript online:
19 November 2024

Article published online:
31 December 2024

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