Intrapartum fetal surveillance

Clinical suspicion, management and outcome of intrapartum foetal distress in a public hospital with limited advanced foetal surveillance

OBJECTIVES

To determine the basis for the clinical suspicion of foetal distress, the instituted managements and delivery outcome in a tertiary hospital in sub-Saharan Africa with limited capability for advanced foetal monitoring.

METHODS

It is a 3-year retrospective analysis of all the obstetrics cases with intrapartum foetal distress.

RESULTS

There were 301 cases reviewed. The birth asphyxia incidence rate was 233/1000 live births and the perinatal death rate was 47/1000 live births. Suspicion of foetal distress was premised on the presence of persistent tachycardia or bradycardia during intermittent auscultation. Main resuscitative measures were left lateral repositioning of patient, fast saline infusion, intranasal oxygen administration and discontinuation of oxytocin infusion, if any. Only 124 (41.2%) of all the cases had delivery achieved within 2 h of diagnosis. Mean decision-delivery interval by caesarean section was 2.93 ± 2.05 h. Socio-demographic factors (p= 0.001) and pregnancy risk category (p = 0.002) influenced incidence of birth asphyxia.

CONCLUSION

To reduce subsisting high perinatal morbidity and mortality in sub-Saharan Africa, it is best that at the least referral hospitals should have advanced facilities for foetal monitoring and shortened surgical intervention time.

Multistage principal component analysis based method for abdominal ECG decomposition

Reflection of fetal heart electrical activity is present in registered abdominal ECG signals. However this signal component has noticeably less energy than concurrent signals, especially maternal ECG. Therefore traditionally recommended independent component analysis, fails to separate these two ECG signals. Multistage principal component analysis (PCA) is proposed for step-by-step extraction of abdominal ECG signal components. Truncated representation and subsequent subtraction of cardio cycles of maternal ECG are the first steps. The energy of fetal ECG component then becomes comparable or even exceeds energy of other components in the remaining signal. Second stage PCA concentrates energy of the sought signal in one principal component assuring its maximal amplitude regardless to the orientation of the fetus in multilead recordings. Third stage PCA is performed on signal excerpts representing detected fetal heart beats in aim to perform their truncated representation reconstructing their shape for further analysis. The algorithm was tested with PhysioNet Challenge 2013 signals and signals recorded in the Department of Obstetrics and Gynecology, Lithuanian University of Health Sciences. Results of our method in PhysioNet Challenge 2013 on open data set were: average score: 341.503 bpm(2) and 32.81 ms.