Cardiotocography and beyond: a review of one-dimensional Doppler ultrasound application in fetal monitoring

• Type of Material: Article
• Authors: Faezeh Marzbanrad, Monash University; Lisa Stroux, University of Oxford; Gari D. Clifford, Emory University
• Language: English
• Date: 2018-08-01
• Publisher: IOP Publishing: Hybrid Open Access
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2018 Institute of Physics and Engineering in Medicine.
• Final Published Version (URL): http://dx.doi.org/10.1088/1361-6579/aad4d1
• Title of Journal or Parent Work: Physiological Measurement
• ISSN: 0967-3334
• Volume: 39
• Issue: 8
• Start Page: 08TR01
• End Page: 08TR01
• Grant/Funding Information: GC acknowledges the support of the National Institutes of Health; the Fogarty International Center; and the Eunice Kennedy Shriver National Institute of Child Health and Human Development, grant number 1R21HD084114– 01 (Mobile Health Intervention to Improve Perinatal Continuum of Care in Guatemala).; LS acknowledges the support of the RCUK Digital Economy Programme grant number EP/G036861/1 (Oxford Centre for Doctoral Training in Healthcare Innovation); and of the Oxford Centre for Affordable Healthcare Technology.
• Keywords: fetal monitoring; FOR-GESTATIONAL-AGE; NONSTRESS TEST; Technology; PRE-EJECTION PERIOD; cardiac time intervals; cardiotocography (CTG); NONINVASIVE MEASUREMENT; UMBILICAL ARTERY; Engineering; Engineering, Biomedical; MYOCARDIAL PERFORMANCE INDEX; Biophysics; Science & Technology; Doppler ultrasound; HEART-RATE-VARIABILITY; LAST MENSTRUAL PERIOD; VELOCITY WAVE-FORMS; Life Sciences & Biomedicine; fetal heart; fetal development; Physiology; ISOVOLUMETRIC CONTRACTION TIME; fetal heart rate (FHR)
• Research Categories: Biology, Bioinformatics; Engineering, Biomedical

Abstract

One-dimensional Doppler ultrasound (1D-DUS) provides a low-cost and simple method for acquiring a rich signal for use in cardiovascular screening. However, despite the use of 1D-DUS in cardiotocography (CTG) for decades, there are still challenges that limit the effectiveness of its users in reducing fetal and neonatal morbidities and mortalities. This is partly due to the noisy, transient, complex and nonstationary nature of the 1D-DUS signals. Current challenges also include lack of efficient signal quality metrics, insufficient signal processing techniques for extraction of fetal heart rate and other vital parameters with adequate temporal resolution, and lack of appropriate clinical decision support for CTG and Doppler interpretation. Moreover, the almost complete lack of open research in both hardware and software in this field, as well as commercial pressures to market the much more expensive and difficult to use Doppler imaging devices, has hampered innovation. This paper reviews the basics of fetal cardiac function, 1D-DUS signal generation and processing, its application in fetal monitoring and assessment of fetal development and wellbeing. It also provides recommendations for future development of signal processing and modeling approaches, to improve the application of 1D-DUS in fetal monitoring, as well as the need for annotated open databases.