Computing techniques for intrapartum physiological data reduction. I. Uterine activity

Application of remote fetal heart rate monitoring via internet in late pregnancy during the COVID-19 pandemic

BACKGROUND

Internet-related technologies have rapidly developed and started to impact the traditional medical practices, which combined wireless communication technology as well as "cloud service" technology with electronic fetal heart monitoring have become a mainstream tendency.

OBJECTIVE

To investigate the clinical application value of remote fetal heart rate monitoring mode (RFHRM) on late pregnancy during the coronavirus disease (COVID-19) pandemic.

METHODS

From March 2021 to February 2022, we recruited 800 cases of pregnant women received prenatal examination at the Anhui Province Maternity and Child Healthcare Hospital. These pregnant women were randomly divided into two groups: the control group (n= 400), which was given traditional management, and the observation group (n= 400), which received remote monitoring technology on this basis. The two groups were compared with neonatal asphyxia, pregnancy outcomes, Edinburgh postnatal depression scale (EPDS), prenatal examination expenses and total time consumption.

RESULTS

There were no statistically significant differences between the groups in pregnancy outcome and neonatal outcome (P> 0.05). However, total EPDS score of 12.5% pregnant women in TPE group were higher than 12. The TPE group had significantly higher mean EPDS scores compared with the RFHRM group (7.79 ± 3.58 vs 5.10 ± 3.07; P< 0.05). The results showed a significant difference in maternity expenses (2949.83 ± 456.07 vs 2455.37 ± 506.67; P< 0.05) and total time consumption (42.81 ± 7.60 vs 20.43 ± 4.16; P< 0.05) between the groups.

CONCLUSION

Remote fetal heart rate monitoring via Internet served as an innovative, acceptable, safe and effective reduced-frequency prenatal examination model without affecting the outcome of perinatology of pregnant women with different risk factors.

Uterine electromyography: a critical review

On the basis of a literature review, this work summarizes uterine animal and human electromyographic information obtained at cellular, myometrial, and abdominal levels during gestation and parturition. We show that both internal and external electromyograms occur in phase with intrauterine pressure increase and exhibit similar spectra, including a slow wave (0.01 < frequency < 0.03 Hz) probably because of mechanical artifacts and a fast wave whose frequency content can be subdivided into a low-frequency band always present in every contraction and a high-frequency band related to efficient parturition contractions. Application of classic spectral techniques to electromyogram envelopes has identified group propagation but not pacemaker areas. However, no time delay or classic propagation has been demonstrated by applying the same spectral techniques to the electromyogram itself, probably because of the nonlinearity and three-dimensional nature of the propagating process.

Standards in fetal monitoring--practical requirements for uterine activity measurement and recording

External monitoring of uterine contractility in human labour can record contraction frequency accurately, but cannot determine true intra-uterine pressure reliably. It is therefore suitable for use in spontaneous labour where there is a need for a marker of contractions to aid in continuous fetal heart rate pattern interpretation. Intra-uterine pressure measurement can provide quantitative information more reliably over intervals of 10-60 minutes. Although active pressure values for individual contractions can vary by up to 50% when measured simultaneously by two or more intra-uterine catheters/transducers, this variation is not systematic and cumulative measures vary by less than 5%. The measurement of baseline tone is affected by variables not related to uterine activity and should therefore be excluded when quantitative measures are made.

Normal levels of active contraction area in spontaneous labour

A detailed study has been made of uterine activity in a group of 21 unselected women in spontaneous labour. Measurements were made of contraction frequency, active pressure, Montevideo units and active contraction area. The level of Montevideo units were comparable with values previously reported in spontaneous labour. Active contraction area correlated better than any of the other measures with the rate of cervical dilatation in the active phase of labour (r = 0.69). The mean contraction area was 1099 (SD 333) kPas/15 min.

Application of a real-time microcomputer monitoring system: surveillance of induced labour by uterine activity quantitation

The uterine activity of women during induced labour was analysed with a real-time Commodore PET 2001 series microcomputer. The active contraction area was measured in torr-min (1 torr = 0.133 kPa) per 10 min epochs [uterine activity unit (UAU)/10 min]. Surgical induction was followed immediately by administration of a geometric oxytocin infusion and all patients received epidural analgesia. Twenty-eight primigravidae for whom inductographic and partographic progress were normal had a mean 'stable phase' uterine activity of 118 +/- 2 SD 43 UAU/10 min (identical to 942 +/- 2 SD 343 kPas/10 min) whereas 15 multiparae had a mean 'stable phase' of 83 +/- 2 SD 34 UAU/10 min (identical to 662 +/- 2 SD 271 kPas/10 min). This difference was significant (P less than 0.01). The construction of uterine activity charts is described and their clinical application discussed.

Feto-maternal surveillance in labour: a new approach with an on-line microcomputer

A new method of real-time computer surveillance during labour is described with a commercially available "low-cost' microcomputer and integral video display unit (VDU). The fetal monitoring program gives accurate and reliable information on eight parameters of fetal and maternal wellbeing, four of which may be displayed simultaneously, with the facility of instant data recall. Emphasis is on simplicity of operation, and clarity of data display in the form of horizontal bar graphs updated at 5-min intervals, with most recent information in numerical form. Flexibility of the system enables program modification with relative ease, and adaptation to two unmodified commercial electronic fetal monitors.