Computerized analysis of the fetal heart rate in pregnancies complicated by preterm premature rupture of membranes (pPROM)

Value of fetal echocardiographic examination in pregnancies complicated by preterm premature rupture of membranes

OBJECTIVES

Cardiopulmonary and infectious complications are more common in preterm newborns after preterm premature rupture of membranes (pPROM). Fetal echocardiography may be helpful in predicting neonatal condition. Our aim was to assess the cardiovascular changes in fetuses from pregnancies complicated by pPROM and possible utility in predicting the intrauterine or neonatal infection, and neonatal heart failure (HF).

METHODS

It was a prospective study enrolling 46 women with singleton pregnancies complicated by pPROM between 18+0 and 33+6 weeks of gestation and followed until delivery. 46 women with uncomplicated pregnancies served as a control group. Fetal echocardiographic examinations with the assessment of cardiac structure and function (including pulmonary circulation) were performed in all patients.

RESULTS

Mean gestational age of pPROM patients was 26 weeks. Parameters suggesting impaired cardiac function in fetuses from pPROM were: higher right ventricle Tei index (0.48 vs. 0.42 p<0.001), lower blood flow velocity in Ao z-score (0.14 vs. 0.84 p=0.005), lower cardiovascular profile score (CVPS), higher rate of tricuspid regurgitation (18.2 % vs. 4.4 % p=0.04) and pericardial effusion (32.6 vs. 0 %). Intrauterine infection was diagnosed in 18 patients (39 %). 4 (8.7 %) newborns met the criteria of early onset sepsis (EOS). HF was diagnosed in 9 newborns. In fetal echocardiographic examination HF group had shorter mitral valve inflow time and higher left ventricle Tei index (0.58 vs. 0.49 p=0.007).

CONCLUSIONS

Worse cardiac function was observed in fetuses from pPROM compared to fetuses from uncomplicated pregnancies.

Chorioamnionitis following preterm premature rupture of membranes and fetal heart rate variability

Introduction

The objective of this study was to identify prenatal markers of histological chorioamnionitis (HC) during pPROM using fetal computerized cardiotocography (cCTG).

Materials and methods

Retrospective review of medical records from pregnant women referred for pPROM between 26 and 34 weeks, in whom placental histology was available, in a tertiary level obstetric service over a 5-year period. Fetal heart rate variability was assessed using cCTG. Patients were included if they were monitored at least six times in the 72 hours preceding delivery. Clinical and biological cCTG parameters during the pPROM latency period were compared between cases with or without HC.

Results

In total, 222 pPROM cases were observed, but cCTG data was available in only 23 of these cases (10 with and 13 without HC) after exclusion of co-morbidities which may potentially perturb fetal heart rate variability measures. Groups were comparable for maternal age, parity, gestational age at pPROM, pPROM duration and neonatal characteristics (p>0.1). Baseline fetal heart rate was higher in the HC group [median 147.3 bpm IQR (144.2–149.2) vs. 141.3 bpm (137.1–145.4) in no HC group; p = 0.02]. The number of low variation episodes [6.4, (3.5–15.3) vs. 2.3 (1–5.2); p = 0.04] was also higher in the HC group, whereas short term variations were lower in the HC group [7.1 ms (6–7.4) vs. 8.1 ms (7.4–9); p = 0.01] within 72 hours before delivery. Differences were especially discriminant within 24 hours before delivery, with less short-term variation [5 ms (3.7–5.9) vs. 7.8 ms (5.4–8.7); p = 0.007] and high variation episodes [3.9 (4.9–3.2) vs. 0.8 (1.5–0.2); p < 0.001] in the HC group.

Conclusion

These results show differences in fetal heart rate variability, suggesting that cCTG could be used clinically to diagnoses chorioamnionitis during the pPROM latency period.

Antenatal cardiotocography for fetal assessment

BACKGROUND

Cardiotocography (CTG) is a continuous recording of the fetal heart rate obtained via an ultrasound transducer placed on the mother's abdomen. CTG is widely used in pregnancy as a method of assessing fetal well-being, predominantly in pregnancies with increased risk of complications.

OBJECTIVES

To assess the effectiveness of antenatal CTG (both traditional and computerised assessments) in improving outcomes for mothers and babies during and after pregnancy.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (26 June 2015) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised and quasi-randomised trials that compared traditional antenatal CTG with no CTG or CTG results concealed; computerised CTG with no CTG or CTG results concealed; and computerised CTG with traditional CTG.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy.

MAIN RESULTS

Six studies (involving 2105 women) are included. Overall, the included studies were not of high quality, and only two had both adequate randomisation sequence generation and allocation concealment. All studies that were able to be included enrolled only women at increased risk of complications.Comparison of traditional CTG versus no CTG showed no significant difference identified in perinatal mortality (risk ratio (RR) 2.05, 95% confidence interval (CI) 0.95 to 4.42, 2.3% versus 1.1%, four studies, N = 1627, low quality evidence) or potentially preventable deaths (RR 2.46, 95% CI 0.96 to 6.30, four studies, N = 1627), though the meta-analysis was underpowered to assess this outcome. Similarly, there was no significant difference identified in caesarean sections (RR 1.06, 95% CI 0.88 to 1.28, 19.7% versus 18.5%, three trials, N = 1279, low quality evidence). There was also no significant difference identified for secondary outcomes related to Apgar scores less than seven at five minutes (RR 0.83, 95% CI 0.37 to 1.88, one trial, N = 396, very low quality evidence); or admission to neonatal special care units or neonatal intensive care units (RR 1.08, 95% CI 0.84 to 1.39, two trials, N = 883, low quality evidence), nor in the other secondary outcomes that were assessed.There were no eligible studies that compared computerised CTG with no CTG.Comparison of computerised CTG versus traditional CTG showed a significant reduction in perinatal mortality with computerised CTG (RR 0.20, 95% CI 0.04 to 0.88, two studies, 0.9% versus 4.2%, 469 women, moderate quality evidence). However, there was no significant difference identified in potentially preventable deaths (RR 0.23, 95% CI 0.04 to 1.29, two studies, N = 469), though the meta-analysis was underpowered to assess this outcome. There was no significant difference identified in caesarean sections (RR 0.87, 95% CI 0.61 to 1.24, 63% versus 72%, one study, N = 59, low quality evidence), Apgar scores less than seven at five minutes (RR 1.31, 95% CI 0.30 to 5.74, two studies, N = 469, very low quality evidence) or in secondary outcomes.

AUTHORS' CONCLUSIONS

There is no clear evidence that antenatal CTG improves perinatal outcome, but further studies focusing on the use of computerised CTG in specific populations of women with increased risk of complications are warranted.

Comparison of a novel computerized analysis program and visual interpretation of cardiotocography

Objective

To compare a novel computerized analysis program with visual cardiotocography (CTG) interpretation results.

Methods

Sixty-two intrapartum CTG tracings with 20- to 30-minute sections were independently interpreted using a novel computerized analysis program, as well as the visual interpretations of eight obstetricians, to evaluate the baseline fetal heart rate (FHR), baseline FHR variability, number of accelerations, number/type of decelerations, uterine contraction (UC) frequency, and the National Institute of Child Health and Human Development (NICHD) 3-Tier FHR classification system.

Results

There was no significant difference in interobserver variation after adding the components of computerized analysis to results from the obstetricians' visual interpretations, with excellent agreement for the baseline FHR (ICC 0.91), the number of accelerations (ICC 0.85), UC frequency (ICC 0.97), and NICHD category I (kappa statistic 0.91); good agreement for baseline variability (kappa statistic 0.68), the numbers of early decelerations (ICC 0.78) and late decelerations (ICC 0.67), category II (kappa statistic 0.78), and overall categories (kappa statistic 0.80); and moderate agreement for the number of variable decelerations (ICC 0.60), and category III (kappa statistic 0.50).

Conclusions

This computerized analysis program is not inferior to visual interpretation, may improve interobserver variations, and could play a vital role in prenatal telemedicine.

Antenatal cardiotocography for fetal assessment

BACKGROUND

Cardiotocography (CTG) is a continuous recording of the fetal heart rate obtained via an ultrasound transducer placed on the mother's abdomen. CTG is widely used in pregnancy as a method of assessing fetal well-being, predominantly in pregnancies with increased risk of complications.

OBJECTIVES

To assess the effectiveness of antenatal CTG (both traditional and computerised assessments) in improving outcomes for mothers and babies during and after pregnancy.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (9 July 2012) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised and quasi-randomised trials that compared traditional antenatal CTG with no CTG or CTG results concealed; computerised CTG with no CTG or CTG results concealed; and computerised CTG with traditional CTG.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility, quality and extracted data.

MAIN RESULTS

Six studies (involving 2105 women) are included. Overall, the included studies were not of high quality, and only two had both adequate randomisation sequence generation and allocation concealment. All studies that were able to be included enrolled only women at increased risk of complications.Comparison of traditional CTG versus no CTG showed no significant difference identified in perinatal mortality (risk ratio (RR) 2.05, 95% confidence interval (CI) 0.95 to 4.42, 2.3% versus 1.1%, four studies, N = 1627) or potentially preventable deaths (RR 2.46, 95% CI 0.96 to 6.30, four studies, N = 1627), though the meta-analysis was underpowered to assess this outcome. Similarly, there was no significant difference identified in caesarean sections (RR 1.06, 95% CI 0.88 to 1.28, 19.7% versus 18.5%, three trials, N = 1279) nor in the secondary outcomes that were assessed.There were no eligible studies that compared computerised CTG with no CTG.Comparison of computerised CTG versus traditional CTG showed a significant reduction in perinatal mortality with computerised CTG (RR 0.20, 95% CI 0.04 to 0.88, two studies, 0.9% versus 4.2%, 469 women). However, there was no significant difference identified in potentially preventable deaths (RR 0.23, 95% CI 0.04 to 1.29, two studies, N = 469), though the meta-analysis was underpowered to assess this outcome. There was no significant difference identified in caesarean sections (RR 0.87, 95% CI 0.61 to 1.24, 63% versus 72%, one study, N = 59) or in secondary outcomes.

AUTHORS' CONCLUSIONS

There is no clear evidence that antenatal CTG improves perinatal outcome, but further studies focusing on the use of computerised CTG in specific populations of women with increased risk of complications are warranted.

Antenatal cardiotocography for fetal assessment

BACKGROUND

Cardiotocography (CTG) is a continuous recording of the fetal heart rate obtained via an ultrasound transducer placed on the mother's abdomen. CTG is widely used in pregnancy as a method of assessing fetal well-being, predominantly in pregnancies with increased risk of complications.

OBJECTIVES

To assess the effectiveness of antenatal CTG (both traditional and computerised assessments) in improving outcomes for mothers and babies during and after pregnancy.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (April 2009).

SELECTION CRITERIA

Randomised and quasi-randomised trials that compared traditional antenatal CTG with no CTG or CTG results concealed; computerised CTG with no CTG or CTG results concealed; and computerised CTG with traditional CTG.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed eligibility, quality and extracted data.

MAIN RESULTS

Six studies (involving 2105 women) are included. Overall, the included studies were not of high quality, and only two had both adequate randomisation sequence generation and allocation concealment. All studies that were able to be included enrolled only women at increased risk of complications.Comparison of traditional CTG versus no CTG showed no significant difference identified in perinatal mortality (risk ratio (RR) 2.05, 95% confidence interval (CI) 0.95 to 4.42, 2.3% versus 1.1%, four studies, N = 1627) or potentially preventable deaths (RR 2.46, 95% CI 0.96 to 6.30, four studies, N = 1627, though the meta-analysis was underpowered to assess this outcome. Similarly, there was no significant difference identified in caesarean sections (RR 1.06, 95% CI 0.88 to 1.28, 19.7% versus 18.5%, three trials, N = 1279) nor in the secondary outcomes that were assessed.There were no eligible studies that compared computerised CTG with no CTG.Comparison of computerised CTG versus traditional CTG showed a significant reduction in perinatal mortality with computerised CTG (RR 0.20, 95% CI 0.04 to 0.88, two studies, 0.9% versus 4.2%, 469 women, graph 3.1.1). However, there was no significant difference identified in potentially preventable deaths (RR 0.23, 95% CI 0.04 to 1.29, two studies, N = 469), though the meta-analysis was underpowered to assess this outcome. There was no significant difference identified in caesarean sections (RR 0.87, 95% CI 0.61 to 1.24, 63% versus 72%, one study, N = 59) or in secondary outcomes.

AUTHORS' CONCLUSIONS

There is no clear evidence that antenatal CTG improves perinatal outcome, but further studies focusing on the use of computerised CTG in specific populations of women with increased risk of complications are warranted.

Fetal distress evaluation using and analyzing the variables of antepartum computerized cardiotocography

OBJECTIVE

In this study, we tried to establish cut-off values for more than one parameters of computerized cardiotocography (c CTG) in the prediction of fetal distress during labor, using a group of pregnant women with low-risk pregnancies.

METHOD

A retrospective study was performed. Data were collected from 167 patients for measurements of fetal heart rate (FHR) variables and perinatal outcome. Computerized CTG was performed with an Oxford Sonicaid monitor with connection to a 8000 system for CTG spontaneous analysis. The following c CTG variables were considered: FHR, number of accelerations, the presence and the number of episodes of high and low variation, the number of decelerations, short-term variation (STV), peaks of contractions (per hour) and fetal movements assessed by maternal perception (per hour). Computerized CTG recordings started not earlier than the beginning of week 38 of gestation. Immediately after delivery, blood sample was collected from umbilical artery for umbilical artery blood gas analysis (UBGA). The main UBGA parameter in cord umbilical artery that was considered for analysis was pH. pH values<7.25 were considered as suspicious for acidemia and pH values>or=7.25 as normal.

RESULTS

Women suspicious for fetal distress during labor presented significantly lower fetal movements (P=0.026), accelerations (P=0.018), variability (P<0.001), number of high episodes (P<0.001), higher values of FHR baseline (P<0.001) and low episodes (P<0.001). Only the number of decelerations did not differ significantly between the two groups (P=0.545). The cut-off points of 5.00 for STV and 3.00 for high episodes were determined to classify women with fetal distress, which yielded high sensitivities (34 and 52%) and specificities (96.6 and 94.9%), with positive predictive values of 81.0 and 81.3% and negative predictive values of 77.4 and 82.2%, respectively.

CONCLUSIONS

In conclusion, we believe that not only STV but also other components of the cCTG, mainly the presence and the number of episodes of high variation, are related to pregnancy's outcome as measured by an umbilical artery pH.