Protocol for a randomised controlled trial of fetal scalp blood lactate measurement to reduce caesarean sections during labour: the Flamingo trial [ACTRN12611000172909]

Psychosocial outcomes from one cohort participating in the STan Australian Randomised controlled Trial (START)

BACKGROUND

In an Australian randomized controlled trial (RCT), two techniques for intrapartum fetal surveillance were compared: ST analysis (STan) as an adjunct to cardiotocography (CTG), compared with CTG alone. The aim was to determine whether CTG + STan could reduce emergency cesarean birth rates while maintaining or improving neonatal outcomes. Secondary aims were to compare clinical, economic, and psychosocial outcomes. The purpose of this paper was to present psychosocial outcomes from one cohort enrolled in the trial.

METHODS

The study was conducted at one tertiary referral hospital. Participants who had taken part in the trial from the outset were invited to complete a questionnaire between March 2018 and January 2020, approximately 8 weeks after giving birth. Outcomes included depression, psychological distress, health-related quality of life, and infant feeding practices. Analysis was by intention to treat.

RESULTS

N = 207/527 participants completed the questionnaire (n = 113, STan; n = 94, CTG alone). Overall, no statistically significant or clinically meaningful differences were found in the two groups for symptoms of depression, psychological distress, quality of life, or infant feeding. A statistically significant difference was observed for the subscale of pain-discomfort, where scores were higher on average in the CTG alone arm relative to that in the CTG + STan arm.

CONCLUSIONS

Although STan as an adjunct to CTG constitutes a different clinical technology from CTG alone, both monitoring types appeared to produce similar results in terms of postnatal psychosocial outcomes for women. Findings from this study provide service users and staff with a comprehensive assessment of STan that can be used to make evidence-informed decisions about monitoring options should STan become more widely available.

Methods for Monitoring Risk of Hypoxic Damage in Fetal and Neonatal Brains: A Review

Fetal, perinatal, and neonatal asphyxia are vital health issues for the most vulnerable groups in human beings, including fetuses, newborns, and infants. Severe reduction in oxygen and blood supply to the fetal brain can cause hypoxic-ischemic encephalopathy, leading to long-term neurological disorders, including mental impairment and cerebral palsy. Such neurological disorders are major healthcare concerns. Therefore, there has been a continuous effort to develop clinically useful diagnostic tools for accurately and quantitatively measuring and monitoring blood and oxygen supply to the fetal and neonatal brain to avoid severe consequences of asphyxia Hypoxic-Ischemic Encephalopathy (HIE) and Neonatal Encephalopathy (NE). Major diagnostic technologies used for this purpose include fetal heart rate monitoring (FHRM), fetus scalp blood sampling (FBS), ultrasound (US) imaging, magnetic resonance imaging (MRI), x-ray computed tomography (CT), and nuclear medicine. In addition, given the limitations and shortcomings of traditional diagnostic methods, emerging technologies such as near-infrared spectroscopy (NIRS) and photoacoustic (PA) imaging have also been introduced as stand-alone or complementary solutions to address this critical gap in fetal and neonatal care. This review provides a thorough overview of the traditional and emerging technologies for monitoring fetal and neonatal brain oxygenation status and describes their clinical utility, performance, advantages, and disadvantages.

The addition of fetal scalp blood lactate measurement as an adjunct to cardiotocography to reduce caesarean sections during labour: The Flamingo randomised controlled trial

BACKGROUND

Fetal scalp blood sampling for lactate measurement (FBSLM) is sometimes used to assist in identification of the need for expedited birth in the presence of an abnormal cardiotocograph (CTG). However, there is no randomised controlled trial evidence to support this.

AIM

To determine whether adding FBSLM reduces the risk of birth by emergency caesarean section in labours complicated by an abnormal CTG, compared with CTG without FBS.

MATERIAL AND METHODS

Labouring women at a tertiary maternity hospital in Melbourne, Australia with a singleton, cephalic presentation, at ≥37 weeks gestation with an abnormal CTG pattern were randomised to the intervention (n = 61), with intermittent FBSLM in addition to CTG monitoring, or control (CTG without FBS, n = 62). The primary outcome was rate of birth by caesarean section. Secondary outcomes included overall operative birth and fetal and neonatal safety endpoints.

TRIAL REGISTRATION

ACTRN12611000172909.

RESULTS

The smaller than anticipated sample was unable to demonstrate an effect from adding FBSLM to CTG monitoring on birth by caesarean section vs monitoring by CTG without FBS (25/61 and 28/62 respectively, P = 0.64, risk ratio 0.91, 95% confidence intervals 0.60-1.36). One newborn infant in the CTG group met the criteria for the composite neonatal outcome of death or serious outcome, neonatal encephalopathy, five-minute Apgar score < 4, neonatal resuscitation, admission to neonatal intensive care unit for 96 h or more.

CONCLUSION

We were unable to provide robust evidence of the effectiveness of FBSLM to improve the specificity of the CTG in the assessment of fetal wellbeing.

Fetal scalp blood sampling during second stage of labor - analyzing lactate or pH? A secondary analysis of a randomized controlled trial

Background: Cardiotocography (CTG) is a widely used method for assessing fetal wellbeing during labor. It is well-known that CTG has high sensitivity but low specificity. To avoid unnecessary operative interventions, adjunctive methods such as fetal blood sampling (FBS) are used. Few studies have looked into whether FBS can be used during second stage of labor, and in that case, which of the methods (lactate or pH) are preferred.Objective: To evaluate clinical effectiveness of measuring lactate versus pH in preventing birth acidemia when FBS was performed during second stage of labor.Methods: Secondary analysis of a randomized controlled trial . Thousand three hundred and thirty-eight women with a singleton pregnancy, cephalic presentation, gestational age ≥34 weeks, and indication for FBS during second stage of labor were included.Main outcome measures: Metabolic acidemia (pH <7.05 and base deficit >12 mmol/l) or pH < 7.00 in cord arterial blood at birth.Secondary outcomes: A composite outcome (metabolic acidemia, pH <7 or Apgar score <4), and rates of operative deliveries.Results: Metabolic acidemia occurred in 4.1% in the lactate versus 5.1% in the pH group (relative risk (RR): 0.80; 95% confidence interval (CI): 0.48-1.35) and pH <7 in 1.4% versus 2.8% (RR: 0.51, 95% CI: 0.23-1.13). Composite outcome was found in 3.8 versus 4.9%, respectively (RR: 0.76; 95% CI: 0.46-1.26). No difference in total operative interventions was found. More cesarean deliveries were performed in the lactate group (16.5 vs. 12.4%; RR: 1.33; 95% CI: 1.02-1.74).Conclusion: When analyzing lactate or pH in fetal scalp blood during second stage of labor neonatal outcomes were comparable. The frequency of total operative interventions was similar but more cesarean deliveries were performed in the lactate group.

A qualitative study of a sample of women participating in an Australian randomised controlled trial of intrapartum fetal surveillance

BACKGROUND

The STan Australian Randomised controlled Trial (START), the first of its kind in Australia, compares two techniques of intrapartum fetal surveillance (cardiotocographic electronic fetal monitoring (CTG) plus analysis of the ST segment of the fetal electrocardiogram (STan+CTG) with CTG alone) with the aim of reducing unnecessary obstetric intervention. It is also the first comprehensive intrapartum fetal surveillance (IFS) trial worldwide, including qualitative examination of psychosocial outcomes and cost-effectiveness. In evaluating and implementing healthcare interventions, the perspectives and experiences of individuals directly receiving them is an integral part of a comprehensive assessment. Furthermore, the added value of using qualitative research alongside randomised controlled trials (RCTs) is becoming widely acknowledged.

OBJECTIVE

This study aimed to examine women's experiences with the type of IFS they received in the START trial.

METHODS

Using a qualitative research design, a sample of thirty-two women were interviewed about their experiences with the fetal monitoring they received. Data were analysed using thematic analysis.

FINDINGS

Six themes emerged from analysis: reassurance, mobility, discomfort, perception of the fetal Scalp Electrode (FSE), and overall positive experience.

CONCLUSION

Interestingly, it was found that women who had an FSE in the CTG alone arm of the trial reported very similar experiences to women in the STan+CTG arm of the trial. Despite STan and CTG differing clinically, from women's perspectives, the primary difference between the two techniques was the utilisation (or not) of the FSE. Women were very accepting of STan+CTG as it was perceived and experienced as a more accurate form of monitoring than CTG alone. Findings from this study have significant implications for health professionals including midwives and obstetricians and implications for standard practice and care. The study has demonstrated the importance and significance of incorporating qualitative enquiry within RCTs.

Foetal scalp blood sampling and ST-analysis of the foetal ECG for intrapartum foetal monitoring: a restricted systematic review

BACKGROUND

To investigate if foetal scalp blood sampling (FBS) is useful in preventing foetal metabolic acidosis in labour when ST-analysis of the foetal ECG (STAN ® ) is already being used as a second line technique for intrapartum foetal monitoring with cardiotocography (CTG).

DESIGN

Restricted systematic review.

METHODS

Based on a literature search in July 2019, a restricted systematic review was performed. Studies comparing CTG+STAN ® +FBS with CTG+STAN ® , CTG+FBS or CTG only were included. Observational studies allowing FBS in addition to STAN ® reporting the indications, results and neonatal outcomes were included as well.

RESULTS

Five randomised controlled trials (RCT) and seven observational trials were analysed. Based on the analysis of data coming from one RCT, FBS identifies foetal acidosis in 9.9% when performed in specific situations. Similarly, in observational trials it was found that in up to 10% of cases where STAN ® registration was less reliable, FBS suggested foetal acidosis. However, there is no evidence that FBS in these cases was capable of preventing metabolic acidosis or its neurological consequences.

CONCLUSION

Based on the available literature, no recommendations in favour of combining FBS with STAN ® monitoring can be made.

Comparing the effect of STan (cardiotocographic electronic fetal monitoring (CTG) plus analysis of the ST segment of the fetal electrocardiogram) with CTG alone on emergency caesarean section rates: study protocol for the STan Australian Randomised controlled Trial (START)

BACKGROUND

Cardiotocography is almost ubiquitous in its use in intrapartum care. Although it has been demonstrated that there is some benefit from continuous intrapartum fetal monitoring using cardiotocography, there is also an increased risk of caesarean section which is accompanied by short-term and long-term risks to the mother and child. There is considerable potential to reduce unnecessary operative delivery with up to a 60% false positive diagnosis of fetal distress using cardiotocography alone. ST analysis of the fetal electrocardiogram is a promising adjunct to cardiotocography alone, and permits detection of metabolic acidosis of the fetus, potentially reducing false positive diagnosis of fetal distress.

METHODS

This study will be a single-centre, parallel-group, randomised controlled trial, conducted over 3 years. The primary hypothesis will be that the proportion of women with an emergency caesarean section on ST analysis will not equal that for women on cardiotocography monitoring alone. Participants will be recruited at the Women's and Children's Hospital, a high-risk specialty facility with approximately 5000 deliveries per annum. A total of 1818 women will be randomised to the treatment or conventional arm with an allocation ratio of 1:1, stratified by parity. The primary outcome is emergency caesarean section (yes/no). Statistical analysis will follow standard methods for randomised trials and will be performed on an intention-to-treat basis. Secondary maternal and neonatal outcomes will also be analysed. Additional study outcomes include psychosocial outcomes, patient preferences and cost-effectiveness.

DISCUSSION

Approximately 20% of Australian babies are delivered by emergency caesarean section. This will be the first Australian trial to examine ST analysis of the fetal electrocardiogram as an adjunct to cardiotocography as a potential method for reducing this proportion. The trial will be among the first to comprehensively examine ST analysis, taking into account the impact on psychosocial well-being as well as cost-effectiveness. This research will provide Australian evidence for clinical practice and guideline development as well as for policy-makers and consumers to make informed, evidence-based choices about care in labour.

TRIAL REGISTRATION

ANZCTR, ACTRN1261800006268 . Registered on 19 January 2018.

Caesarean Section Rates and Activity-Based Funding in Northern Norway: A Model-Based Study Using the World Health Organization's Recommendation

OBJECTIVE

Caesarean section (CS) rates vary significantly worldwide. The World Health Organization (WHO) has recommended a maximum CS rate of 15%. Norwegian hospitals are paid per CS (activity-based funding), employing the diagnosis-related group (DRG) system. We aimed to document how financial incentives can be affected by reduced CS rates, according to the WHO's recommendation.

METHODS

We employed a model-based analysis and included the 2016 data from the Norwegian Patient Registry (NPR) and the Medical Birth Registry of Norway (MBRN). The vaginal birth rate and CS rates of each hospital trust in Northern Norway were analyzed.

RESULTS

There were 4,860 deliveries and a 17.5% CS rate (range 13.9-20.3%). The total funding of the deliveries was €16,351,335 (CS: €6,389,323; vaginal births: €9,962,012). The CS rate varied significantly and was lower in the southern region (P < 0.002). Consequently, the introduction of a cutoff at a 15% CS rate would gain the two southern hospital trusts by a budget increase of 0.2%. The two northern ones would experience 6.4% less resources. A total of €644,655 could be allocated to further quality and safety initiatives in obstetrics.

CONCLUSION

The economic consequences of the model-based financial incentive were low, but probably sufficient to get the necessary attention and influence on the CS rate.

RECOMMENDATIONS

A financial incentive for the reduction of CS rates should be tested as a supplement to other instruments.

Infant outcome at four years of age after intrapartum sampling of scalp blood lactate for fetal assessment. A cohort study

OBJECTIVE

To correlate the value of lactate in fetal scalp blood at delivery and the outcomes of the offspring at four years of age.

METHODS

Cases where scalp blood lactate was taken within sixty minutes before delivery were identified from the randomized trial "Determination of pH or lactate in fetal scalp blood in management of intrapartum fetal distress". Data were grouped according to the generally accepted cutoffs for normality, pre-acidemia, acidemia and concentrations above mean +2 SD during the second stage. The outcome measures included gross-/fine motor function, vision, hearing, speaking and cognitive disorders, signs of central motor damage and referral to specialized pediatric services.

RESULTS

307 cases were available for final analyse. With normal scalp lactate concentration, the number of children with a diagnosed disorder was lower compared to the pre-acidemic/acidemic groups, although the findings were only significant for fine motor dysfunction (p = 0.036). Elevated lactate values were significantly associated with increased risk for a poorer capacity of attention and understanding of instructions (OR 1.37, 95% CI 1.07-1.74), and for fine motor dysfunction (OR 1.22, 95% CI 1.00-1.49) at the age of four.

CONCLUSION

Higher levels of lactate in fetal scalp blood seems to be associated with increased risk of an aberrant developmental outcome at four years of age in some areas.