Maternal cardiorespiratory coupling: differences between pregnant and nonpregnant women are further amplified by sleep-stage stratification.

Pregnancy complications are associated with abnormal maternal autonomic regulation. Subsequently, thoroughly understanding maternal autonomic regulation during healthy pregnancy may enable the earlier detection of complications, in turn allowing for the improved management thereof. Under healthy autonomic regulation, reciprocal interactions occur between the cardiac and respiratory systems, i.e., cardiorespiratory coupling (CRC). Here, we investigate, for the first time, the differences in CRC between healthy pregnant and nonpregnant women. We apply two algorithms, namely, synchrograms and bivariate phase-rectified signal averaging, to nighttime recordings of ECG and respiratory signals. We find that CRC is present in both groups. Significantly less (P < 0.01) cardiorespiratory synchronization occurs in pregnant women (11% vs. 15% in nonpregnant women). Moreover, there is a smaller response in the heart rate of pregnant women corresponding to respiratory inhalations and exhalations. In addition, we stratified these analyses by sleep stages. As each sleep stage is governed by different autonomic states, this stratification not only amplified some of the differences between groups but also brought out differences that remained hidden when analyzing the full-night recordings. Most notably, the known positive relationship between CRC and deep sleep is less prominent in pregnant women than in their nonpregnant counterparts. The decrease in CRC during healthy pregnancy may be attributable to decreased maternal parasympathetic activity, anatomical changes to the maternal respiratory system, and the increased physiological stress accompanying pregnancy. This work offers novel insight into the physiology of healthy pregnancy and forms part of the base knowledge needed to detect abnormalities in pregnancy.NEW & NOTEWORTHY We compare CRC, i.e., the reciprocal interaction between the cardiac and respiratory systems, between healthy pregnant and nonpregnant women for the first time. Although CRC is present in both groups, CRC is reduced during healthy pregnancy; there is less synchronization between maternal cardiac and respiratory activity and a smaller response in maternal heart rate to respiratory inhalations and exhalations. Stratifying this analysis by sleep stages reveals that differences are most prominent during deep sleep.

Pregnant patient with acute abdominal pain and previous bariatric surgery.

Pregnant women who previously had bariatric surgery may develop acute abdominal pain during pregnancy. Two patients, 38-year-old twin primigravida (gestational age of 24+6 weeks) and a 26-year-old woman (gestational age of 24+0 weeks), both of whom had laparoscopic gastric bypass surgery previously, developed abdominal pain. The patients both had diffuse abdominal pain in combination with normal blood tests and imaging. Patient B had undergone laparoscopy at another centre after 5 weeks of gestation for internal herniation. After referral to our multidisciplinary bariatric-obstetric-neonatal (MD-BON) team, diagnostic laparoscopy was advised as internal herniation was deemed possible. In both patients, internal herniation was indeed found in Petersen's space and jejunal mesenteric defect, which was closed using laparoscopic surgery. Both women delivered healthy offspring afterwards. The presence of an MD-BON team allows for an increased awareness of potential long-term complications associated with earlier bariatric surgery in pregnancy.

Why -aVF can be used in STAN as a proxy for scalp electrode-derived signal; reply to comments by Kjellmer et al.

The conclusion of our recent paper that performance of the STAN device in clinical practice is potentially limited by high false-negative and high false-positive STAN-event rates and loss of ST waveform assessment capacity during severe hypoxemia, evoked comments by Kjellmer, Lindecrantz and Rosén. These comments can be summarized as follows: 1) STAN analysis is based on a unipolar lead but the authors used a negative aVF lead, and they did not validate this methodology; 2) The fetuses used in the study were too young to display the signals that the authors were trying to detect. In response to these comments we now provide both a theoretical and an experimental underpinning of our approach. In an in vivo experiment in human we placed several electrodes over the head (simulating different places of a scalp electrode), simultaneously recorded Einthoven lead I and II, and constructed -aVF from these two frontal leads. Irrespective of scalp electrode placement, the correlation between any of unipolar scalp electrode-derived signals and constructed-aVF was excellent (≥ 0.92). In response to the second comment we refer to a study which demonstrated that umbilical cord occlusion resulted in rapid increase in T/QRS ratio that coincided with initial hypertension and bradycardia at all gestational ages which were tested from 0.6-0.8 gestation. The animals of our study were in this gestational range and, hence, our experimental setup can be used to assess STAN's quality to detect fetal hypoxia. In conclusion, we have clearly demonstrated the appropriateness of using-aVF as a proxy for a scalp electrode-derived signal in STAN in these preterm lambs. Investigation why STAN could not detect relevant ST-changes and instead produced erroneous alarms in our experimental setup is hampered by the fact that the exact STAN algorithm (signal processing and analysis) is not in the public domain.

Prenatal diagnosis of a bundle branch block based on the fetal ECG.

A non-invasive fetal ECG was performed on a 36-year-old pregnant woman at 24+6 weeks of gestation as part of ongoing clinical research. A paediatric cardiologist suspected an incomplete bundle branch block based on the averaged ECGs from the recording. The characteristic terminal R' wave was present in multiple leads of the fetal ECGs. A fetal anomaly scan had been performed at 20 weeks of gestation and showed no abnormalities. An incomplete right bundle branch block was confirmed on an ECG recorded at the age of 2 years. This case shows the possibility of novel non-invasive fetal ECG technology as an adjunct to the diagnosis of fetal cardiac anomalies in the future.

Early enteral tube feeding in optimizing treatment of hyperemesis gravidarum: the Maternal and Offspring outcomes after Treatment of HyperEmesis by Refeeding (MOTHER) randomized controlled trial.

Background: Hyperemesis gravidarum (HG) leads to dehydration, poor nutritional intake, and weight loss. HG has been associated with adverse pregnancy outcomes such as low birth weight. Information about the potential effectiveness of treatments for HG is limited.Objective: We hypothesized that in women with HG, early enteral tube feeding in addition to standard care improves birth weight.Design: We performed a multicenter, open-label randomized controlled trial [Maternal and Offspring outcomes after Treatment of HyperEmesis by Refeeding (MOTHER)] in 19 hospitals in the Netherlands. A total of 116 women hospitalized for HG between 5 and 20 wk of gestation were randomly allocated to enteral tube feeding for ≥7 d in addition to standard care with intravenous rehydration and antiemetic treatment or to standard care alone. Women were encouraged to continue tube feeding at home. On the basis of our power calculation, a sample size of 120 women was anticipated. Analyses were performed according to the intention-to-treat principle.Results: Between October 2014 and March 2016 we randomly allocated 59 women to enteral tube feeding and 57 women to standard care. The mean ± SD birth weight was 3160 ± 770 g in the enteral tube feeding group compared with 3200 ± 680 g in the standard care group (mean difference: -40 g, 95% CI: -230, 310 g). Secondary outcomes, including maternal weight gain, duration of hospital stay, readmission rate, nausea and vomiting symptoms, decrease in quality of life, psychological distress, prematurity, and small-for-gestational-age, also were comparable. Of the women allocated to enteral tube feeding, 28 (47%) were treated according to protocol. Enteral tube feeding was discontinued within 7 d of placement in the remaining women, primarily because of its adverse effects (34%).Conclusions: In women with HG, early enteral tube feeding does not improve birth weight or secondary outcomes. Many women discontinued tube feeding because of discomfort, suggesting that it is poorly tolerated as an early routine treatment of HG. This trial was registered at www.trialregister.nl as NTR4197.