Effect of intrapartum oxygen on the rate of cesarean delivery: a meta-analysis.

OBJECTIVE: This study aimed to determine if maternal intrapartum administration of oxygen altered the rate of cesarean delivery compared with room air. DATA SOURCES: This study was a systematic review and meta-analysis of randomized controlled trials. Searches were performed in MEDLINE, OVID, Scopus, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials using a combination of key words related to "pregnant patients," "labor," "oxygen," "fetus," "newborn," and pregnancy outcomes from database inception until April 2020. The study was registered in PROSPERO (registration number CRD42020162110). STUDY ELIGIBILITY CRITERIA: The inclusion criteria were randomized controlled trials of maternal administration of oxygen compared with room air in labor. The exclusion criteria were quasi-randomized trials and oxygen administered for planned cesarean deliveries. The primary outcome was the rate of cesarean delivery. Secondary maternal and neonatal outcomes, including cord gas values, were analyzed. METHODS: The Cochrane Handbook guidelines were used to assess bias in trials. To calculate the relative risk or mean differences with confidence intervals, a random-effects model was employed. Subgroup analyses were performed for women who received oxygen for nonreassuring fetal heart rate monitoring or prophylactically. RESULTS: Five randomized controlled trials, including 768 women, were included in the meta-analysis, 3 using prophylactic oxygen and 2 using oxygen for nonreassuring fetal heart rate monitoring. The risk of bias was generally considered low. There was no statistically significant difference in the rate of cesarean delivery between patients administered oxygen and patients provided room air (16 of 365 [4.4%] vs 11 of 379 [2.9%]; risk ratio 1.5; 95% confidence interval, 0.7-3.3). In addition, there were no statistically significant differencs in the rates of cesarean delivery for nonreassuring fetal heart rate monitoring, operative vaginal deliveries, Apgar scores of <7, neonatal intensive care unit admissions, or cord blood gas values. There were no statistically significant difference when analyzing oxygen for nonreassuring fetal heart rate monitoring alone or prophylactic oxygen alone. Data regarding FHT is mixed, with one study suggesting an improvement and three suggesting no change. CONCLUSION: Maternal intrapartum oxygen administration was not associated with any differences in the rate of cesarean delivery or any secondary outcomes compared with room air overall and in the subgroups of therapeutic (for nonreassuring fetal heart rate monitoring) or prophylactic administration in this meta-analysis. Large randomized controlled trials are necessary to further examine any possible benefits or harms of oxygen administration in labor, particularly for nonreassuring fetal heart rate monitoring.

Changes in Maternal Heart Rate Variability in Response to the Administration of Routine Obstetric Medication in Hospitalized Patients: Study Protocol for a Cohort Study (MAMA-Heart Study).

Pregnancy is a period of continuous change in the maternal cardiovascular system, partly mediated by the autonomic nervous system. Insufficient autonomic adaptation to increasing gestation is associated with pregnancy complications, such as hypertensive disorders of pregnancy and preterm birth (both major causes of perinatal morbidity and mortality). Consequently, maternal heart rate variability (mHRV), which is a proxy measure for autonomic activity, is increasingly assessed in these cohorts to investigate the pathophysiology of their complications. A better pathophysiological understanding could facilitate the early detection of these complications, which remains challenging. However, such studies (typically performed in pregnancies leading to hospitalization) have generated conflicting findings. A probable reason for these conflicting findings is that these study cohorts were likely administered routine obstetric medications during the study period of which the effects on mHRV are largely unknown. Subsequently, we design a longitudinal, observational study to quantifying the effect of these medications-particularly corticosteroids, which are known to affect fetal HRV-on mHRV to improve the interpretation of past and future studies. We will enroll 61 women admitted to a tertiary obstetric unit with an indication to receive corticosteroids antenatally. Participants' mHRV will be continuously acquired throughout their hospitalization with wrist-worn photoplethysmography to facilitate a within-patient comparison of the effect of corticosteroids on mHRV.

The effect of intrauterine resuscitation by maternal hyperoxygenation on perinatal and maternal outcome: a randomized controlled trial.

BACKGROUND: Maternal hyperoxygenation is widely used during labor as an intrauterine resuscitation technique. However, robust evidence regarding its beneficial effect and potential side effects is scarce, and previous studies show conflicting results. OBJECTIVE: To assess the effect of maternal hyperoxygenation upon suspected fetal distress during the second stage of term labor on fetal heart rate, neonatal outcome, maternal side effects, and mode of delivery. MATERIALS AND METHODS: In a single-center randomized controlled trial in a tertiary hospital in The Netherlands, participants were randomized in case of an intermediary or abnormal fetal heart rate pattern during the second stage of term labor, to receive either conventional care or 100% oxygen at 10 L/min until delivery. The primary outcome was the change in fetal heart rate pattern. Prespecified secondary outcomes were Apgar score, umbilical cord blood gas analysis, neonatal intensive care unit admission, perinatal death, free oxygen radical activity, maternal side effects, and mode of delivery. We performed subgroup analyses for intermediary and abnormal fetal heart rate, and for small for gestational age fetuses. RESULTS: From March 2016 through April 2018, a total of 117 women were included. Fetal heart rate patterns could be analyzed in 71 women. Changes in fetal heart rate (defined as improvement, equal, or deterioration) in favor of maternal hyperoxygenation were significant (odds ratio, 5.7; 95% confidence interval, 1.7-19.1) using ordinal logistic regression. Apgar score, umbilical cord blood gas analysis, free oxygen radicals, and mode of delivery showed no significant differences between the intervention and control group. Among women with an abnormal fetal heart rate, there were fewer episiotomies on fetal indication in the intervention group (25%) than in the control group (65%, P < .01). CONCLUSION: Maternal hyperoxygenation has a positive effect on the fetal heart rate in the presence of suspected fetal distress during the second stage of labor. There was no significant difference in the mode of delivery or neonatal outcome; however, significantly fewer episiotomies on fetal indication were performed following maternal hyperoxygenation in the subgroup with abnormal fetal heart rate pattern.

Speckle Tracking Echocardiography in Hypertensive Pregnancy Disorders: A Systematic Review.

IMPORTANCE: Hypertensive pregnancy disorders (HPDs) are associated with an increased risk of long-term cardiovascular disease. Speckle tracking echocardiography (STE) might be useful in the early detection of preclinical cardiac changes in women with HPDs. OBJECTIVE: The aim of this study was to study whether STE is a suitable method to detect differences in cardiac function in pregnant women with HPD compared with normotensive pregnant women or between women with a history of a pregnancy complicated by HPD compared with women with a history of an uncomplicated pregnancy. EVIDENCE ACQUISITION: The databases Medline, EMBASE, and Central were systematically searched for studies comparing cardiac function measured with STE in pregnant women with HPD or women with a history of HPD and women with a history of normotensive pregnancies. RESULTS: The search identified 16 studies, including 870 women with a history of HPD and 693 normotensive controls. Most studies during pregnancy (n = 12/13) found a decreased LV-GLS (left ventricular global longitudinal strain) in HPD compared with normotensive pregnant controls. LV-GRS (left ventricular global radial strain) and LV-GLCS (left ventricular global circumferential strain) are decreased in women with early-onset and severe preeclampsia. Women with a history of early-onset preeclampsia show lasting myocardial changes, with significantly decreased LV-GLS, LV-GLCS, and LV-GRS. CONCLUSIONS AND RELEVANCE: LV-GLS is significantly decreased in pregnant women with HPD compared with normotensive pregnant women. Other deformation values show a significant decrease in women with severe or early-onset preeclampsia, with lasting myocardial changes after early-onset preeclampsia.

Correction to: Intrauterine resuscitation during the second stage of term labour by maternal hyperoxygenation versus conventional care: study protocol for a randomised controlled trial (INTEREST O2).

Following publication of the original article [1], the authors noticed that the sample size for the study group was incorrectly reported in the Methods section.

Intrauterine resuscitation during the second stage of term labour by maternal hyperoxygenation versus conventional care: study protocol for a randomised controlled trial (INTEREST O2).

BACKGROUND: Perinatal asphyxia is, even in developed countries, one the major causes of neonatal morbidity and mortality. Therefore, if foetal distress during labour is suspected, one should try to restore foetal oxygen levels or aim for immediate delivery. However, studies on the effect of intrauterine resuscitation during labour are scarce. We designed a randomised controlled trial to investigate the effect of maternal hyperoxygenation on the foetal condition. In this study, maternal hyperoxygenation is induced for the treatment of foetal distress during the second stage of term labour. METHODS/DESIGN: This study is a single-centre randomised controlled trial being performed in a tertiary hospital in The Netherlands. From among cases of a suboptimal or abnormal foetal heart rate pattern during the second stage of term labour, a total of 116 patients will be randomised to the control group, where normal care is provided, or to the intervention group, where before normal care 100% oxygen is supplied to the mother by a non-rebreathing mask until delivery. The primary outcome is change in foetal heart rate pattern. Secondary outcomes are Apgar score, mode of delivery, admission to the neonatal intensive care unit and maternal side effects. In addition, blood gas values and malondialdehyde are determined in umbilical cord blood. DISCUSSION: This study will be the first randomised controlled trial to investigate the effect of maternal hyperoxygenation for foetal distress during labour. This intervention should be recommended only as a treatment for intrapartum foetal distress, when improvement of the foetal condition is likely and outweighs maternal and neonatal side effects. TRIAL REGISTRATION: EudraCT, 2015-001654-15; registered on 3 April 2015. Dutch Trial Register, NTR5461; registered on 20 October 2015.

Practice variation in the management of intrapartum fetal distress in The Netherlands and the Western world.

OBJECTIVE: Solid evidence on the effect of intrauterine resuscitation on neonatal outcome is limited, and superiority of one intervention over the others is not clear. We therefore surveyed the clinical practice variation in fetal monitoring and the management of fetal distress during labor, in Dutch labor wards. In addition, we have compared recommendations from international guidelines. STUDY DESIGN: We conducted a survey among all 86 Dutch hospitals, using a questionnaire on fetal monitoring and management of fetal distress. In addition, we requested international guidelines of 28 Western countries to study international recommendations regarding labor management. RESULTS: The response rate of the national survey was 100%. Labor wards of all hospitals use CTG for fetal monitoring, 98% use additional fetal scalp blood sampling, and 23% use ST-analysis. When fetal distress is suspected, oxytocin is discontinued and tocolytic drugs are applied in all hospitals. Nearly all hospitals (98%) use maternal reposition for fetal resuscitation, 33% use amnioinfusion, and 58% provide maternal hyperoxygenation. Management is mainly based on the Dutch national guideline (58%) or on local guidelines (26%). Eight international guidelines on fetal monitoring were obtained for analysis. Fetal scalp blood sampling facilities are recommended in all the obtained guidelines. Use of ST-analysis is recommended in three guidelines and advised against in three guidelines. Five guidelines also advised on intrauterine resuscitation: discontinuation of oxytocin and use of tocolytic drugs was advised in all guidelines, amnioinfusion was recommended in two guidelines and advised against in two guidelines, whereas maternal hyperoxygenation was recommended in two guidelines and advised against in one guideline. CONCLUSION: Nationwide clinical practice, and recommendations from international guidelines agree on the use of fetal scalp blood sampling in addition to cardiotocography during labor. The opinion on the use of ST-analysis differs per clinic and per guideline. Discontinuation of oxytocin, administration of tocolytic drugs and maternal repositioning are rather uniform, on national and international level. However, there is a large variation in the use of amnioinfusion and maternal hyperoxygenation, which may be explained by the contradictory recommendations of the different guidelines.

Prognostic Relevance of Gene-Environment Interactions in Patients With Dilated Cardiomyopathy: Applying the MOGE(S) Classification.

BACKGROUND: The multifactorial pathogenesis leading to dilated cardiomyopathy (DCM) makes stratification difficult. The recent MOGE(S) (morphofunctional, organ involvement, genetic or familial, etiology, stage) classification addresses this issue. OBJECTIVES: The purpose of this study was to investigate the applicability and prognostic relevance of the MOGE(S) classification in patients with DCM. METHODS: This study used patients from the Maastricht Cardiomyopathy Registry in the Netherlands and excluded patients with ischemic, valvular, hypertensive, and congenital heart disease. All other patients underwent a complete diagnostic work-up, including genetic evaluation and endomyocardial biopsy. RESULTS: A total of 213 consecutive patients with DCM were included: organ involvement was demonstrated in 35 (16%) and genetic or familial DCM in 70 (33%) patients, including 16 (8%) patients with a pathogenic mutation. At least 1 cause was found in 155 (73%) patients, of whom 48 (23%) had more than 1 possible cause. Left ventricular reverse remodeling was more common in patients with nongenetic or nonfamilial DCM than in patients with genetic or familial DCM (40% vs. 25%; p = 0.04). After a median follow-up of 47 months, organ involvement and higher New York Heart Association functional class were associated with adverse outcome (p < 0.001 and p = 0.02, respectively). Genetic or familial DCM per se was of no prognostic significance, but when it was accompanied by additional etiologic-environmental factors such as significant viral load, immune-mediated factors, rhythm disturbances, or toxic triggers, a worse outcome was revealed (p = 0.03). A higher presence of MOGE(S) attributes (≥2 vs. ≤1 attributes) showed an adverse outcome (p = 0.007). CONCLUSIONS: The MOGE(S) classification in DCM is applicable, and each attribute or the gene-environment interaction is associated with outcome. Importantly, the presence of multiple attributes was a strong predictor of adverse outcome. Finally, adaptation of the MOGE(S) involving multiple possible etiologies is recommended.