Sharona Vonck

Maternal venous Doppler characteristics are abnormal in pre‐eclampsia but not in gestational hypertension

To compare functional characteristics of maternal thoraco‐abdominal arteries and veins in proteinuric and non‐proteinuric hypertension in pregnancy.

Remote Monitoring of Hypertension Diseases in Pregnancy: A Pilot Study

Background Although remote monitoring (RM) has proven its added value in various health care domains, little is known about the remote follow-up of pregnant women diagnosed with a gestational hypertensive disorders (GHD). Objective The aim of this study was to evaluate the added value of a remote follow-up program for pregnant women diagnosed with GHD. Methods A 1-year retrospective study was performed in the outpatient clinic of a 2nd level prenatal center where pregnant women with GHD received RM or conventional care (CC). Primary study endpoints include number of prenatal visits and admissions to the prenatal observation ward. Secondary outcomes include gestational outcome, mode of delivery, neonatal outcome, and admission to neonatal intensive care (NIC). Differences in continuous and categorical variables in maternal demographics and characteristics were tested using Unpaired Student’s two sampled t test or Mann-Whitney U test and the chi-square test. Both a univariate and multivariate analysis were performed for analyzing prenatal follow-up and gestational outcomes. All statistical analyses were done at nominal level, Cronbach alpha=.05. Results Of the 166 patients diagnosed with GHD, 53 received RM and 113 CC. After excluding 5 patients in the RM group and 15 in the CC group because of the missing data, 48 patients in RM group and 98 in CC group were taken into final analysis. The RM group had more women diagnosed with gestational hypertension, but less with preeclampsia when compared with CC (81.25% vs 42.86% and 14.58% vs 43.87%). Compared with CC, univariate analysis in RM showed less induction, more spontaneous labors, and less maternal and neonatal hospitalizations (48.98% vs 25.00%; 31.63% vs 60.42%; 74.49% vs 56.25%; and 27.55% vs 10.42%). This was also true in multivariate analysis, except for hospitalizations. Conclusions An RM follow-up of women with GHD is a promising tool in the prenatal care. It opens the perspectives to reverse the current evolution of antenatal interventions leading to more interventions and as such to ever increasing medicalized antenatal care.

Hepatic Hemodynamics and Fetal Growth: A Relationship of Interest for Further Research

Background It is well known that hepatic hemodynamics is an important physiologic mechanism in the regulation of cardiac output (CO). It has been reported that maternal cardiac output relates to neonatal weight at birth. Aims In this study, we assessed the correlation between maternal hepatic vein Doppler flow parameters, cardiac output and neonatal birth weight. Methods Healthy women with uncomplicated second or third trimester pregnancy attending the outpatient antenatal clinic of Ziekenhuis Oost-Limburg in Genk (Belgium), had a standardized combined electrocardiogram-Doppler ultrasound with Impedance Cardiography, for measurement of Hepatic Vein Impedance Index (HVI  =  [maximum velocity – minimum velocity]/maximum velocity), venous pulse transit time (VPTT  =  time interval between corresponding ECG and Doppler wave characteristics) and cardiac output (heart rate x stroke volume). After delivery, a population-specific birth weight chart, established from a cohort of 27000 neonates born in the index hospital, was used to define customized birth weight percentiles (BW%). Correlations between HVI, VPTT, CO and BW% were calculated using Spearmans ρ, linear regression analysis and R2 goodness of fit in SPSS 22.0. Results A total of 73 women were included. There was a negative correlation between HVI and VPTT (ρ = −0.719, p<0.001). Both HVI and VPTT correlated with CO (ρ = −0.403, p<0.001 and ρ = 0.332, p<0.004 resp.) and with BW% (ρ = −0.341, p<0.003 and ρ = 0.296, p<0.011 resp.) Conclusion Our data illustrate that the known contribution of hepatic hemodynamics in the regulation of cardiac output is also true for women with uncomplicated pregnancies. Our study is the first to illustrate a potential link between maternal hepatic hemodynamics and neonatal birth weight. Whether this link is purely associative or whether hepatic vascular physiology has a direct impact on fetal growth is to be evaluated in more extensive clinical and experimental research.

Clinical inference of maternal renal venous Doppler ultrasonography

Abstract Venous compliance is known to differ between uncomplicated and preeclamptic pregnancies and can be assessed using Doppler ultrasonography. The purpose of this report is to address some of the interfering conditions in order to illustrate some of the limitations of venous Doppler sonography. Five case reports of pregnant women with important morbidity were selected: (1) auto-immune vasculitis, (2) polycystic renal dysplasia, (3) hydronephrosis, (4) HELLP syndrome and (5) morbid obesity. All cases had a Doppler flow examination of renal interlobar veins according to a standardized protocol and venous impedance index of left and right kidney was calculated. Results were plotted on a normal reference curve. Renal venous Doppler sonography may be hampered by maternal comorbidities or disease-specific conditions due to which it is difficult or even impossible to perform or interpret the Doppler signal.

Maternal body fluid composition in uncomplicated pregnancies and preeclampsia: a bioelectrical impedance analysis

OBJECTIVES Body fluid composition changes during the course of pregnancy and there is evidence to suggest that these changes are different in uncomplicated pregnancies compared to hypertensive pregnancies. The aim of this study was to evaluate the changes in maternal body fluid composition during the course of an uncomplicated pregnancy and to assess differences in uncomplicated pregnancies versus hypertensive pregnancies by using a bio-impedance analysis technique. STUDY DESIGN Body fluid composition of each patient was assessed using a multiple frequency bioelectrical impedance analyser. Measurements were performed in 276 uncomplicated pregnancies, 34 patients with gestational hypertension, 35 with late onset preeclampsia and 11 with early onset preeclampsia. Statistical analysis was performed at nominal level α=0.05. A longitudinal linear mixed model based analysis was performed for longitudinal evolutions, and ANOVA with a post-hoc Bonferroni was used to identify differences between groups. RESULTS Measurements showed that total body water (TBW), intracellular (ICW) and extracellular water (ECW) and ECW/ICW significantly increase during the course of pregnancy. Late onset preeclampsia is associated with a higher TBW and ECW as compared to uncomplicated pregnancies, the ECW/ICW ratio is higher in preeclamptic patients compared to uncomplicated pregnancies and gestational hypertension, and ICW is not different between groups. CONCLUSION Body fluid composition changes differently during the course of uncomplicated pregnancies versus hypertensive pregnancies.

Type-specific orthostatic hemodynamic response of hypertensive diseases in pregnancy

Posture changes may differ between types of hypertensive disease. The aim is to evaluate the orthostatic response of impedance cardiography (ICG) measurements in uncomplicated and hypertensive pregnancies. Measurements were performed in supine and standing position in 202 women: 41 uncomplicated pregnancies (UP), 59 gestational hypertension (GH), 35 early‐onset (EPE, < 34 weeks) and 67 late‐onset (LPE, ≥ 34 weeks) preeclampsia were assessed. Measurements were recorded of heart rate, blood pressure, aortic flow parameters, cardiac output, pre‐ejection period and left ventricular ejection time. Overall, orthostatic shifts were different between all groups (P < 0.001). UP was different from the hypertensive complicated gestations in the orthostatic change of the aortic acceleration. In contrast to patients with preeclampsia, those with GH had an increased blood pressure and Heather index, and stable pre‐ejection period after posture change. EPE differed from LPE by change in blood pressure and aortic flow parameters. In addition to static ICG‐measurements, orthostatic shifts improved group characterization from 57.4% to 65.8%. The orthostatic response is altered in hypertensive pregnancies. ICG measurements in the upright as well as during an orthostatic test might have the potential to improve the discriminative yield between hypertensive diseases in pregnancy.

Prenatal Remote Monitoring of Women With Gestational Hypertensive Diseases: Cost Analysis

Background Remote monitoring in obstetrics is relatively new; some studies have shown its effectiveness for both mother and child. However, few studies have evaluated the economic impact compared to conventional care, and no cost analysis of a remote monitoring prenatal follow-up program for women diagnosed with gestational hypertensive diseases (GHD) has been published. Objective The aim of this study was to assess the costs of remote monitoring versus conventional care relative to reported benefits. Methods Patient data from the Pregnancy Remote Monitoring (PREMOM) study were used. Health care costs were calculated from patient-specific hospital bills of Ziekenhuis Oost-Limburg (Genk, Belgium) in 2015. Cost comparison was made from three perspectives: the Belgian national health care system (HCS), the National Institution for Insurance of Disease and Disability (RIZIV), and costs for individual patients. The calculations were made for four major domains: prenatal follow-up, prenatal admission to the hospital, maternal and neonatal care at and after delivery, and total amount of costs. A simulation exercise was made in which it was calculated how much could be demanded of RIZIV for funding the remote monitoring service. Results A total of 140 pregnancies were included, of which 43 received remote monitoring (30.7%) and 97 received conventional care (69.2%). From the three perspectives, there were no differences in costs for prenatal follow-up. Compared to conventional care, remote monitoring patients had 34.51% less HCS and 41.72% less RIZIV costs for laboratory test results (HCS: mean €0.00 [SD €55.34] vs mean €38.28 [SD € 44.08], P<.001; RIZIV: mean €21.09 [SD €27.94] vs mean €36.19 [SD €41.36], P<.001) and a reduction of 47.16% in HCS and 48.19% in RIZIV costs for neonatal care (HCS: mean €989.66 [SD €3020.22] vs mean €1872.92 [SD €5058.31], P<.001; RIZIV: mean €872.97 [SD €2761.64] vs mean €1684.86 [SD €4702.20], P<.001). HCS costs for medication were 1.92% lower in remote monitoring than conventional care (mean €209.22 [SD €213.32] vs mean €231.32 [SD 67.09], P=.02), but were 0.69% higher for RIZIV (mean €122.60 [SD €92.02] vs mean €121.78 [SD €20.77], P<.001). Overall HCS costs for remote monitoring were mean €4233.31 (SD €3463.31) per person and mean €4973.69 (SD €5219.00) per person for conventional care (P=.82), a reduction of €740.38 (14.89%) per person, with savings mainly for RIZIV of €848.97 per person (23.18%; mean €2797.42 [SD €2905.18] vs mean €3646.39 [SD €4878.47], P=.19). When an additional fee of €525.07 per month per pregnant woman for funding remote monitoring costs is demanded, remote monitoring is acceptable in their costs for HCS, RIZIV, and individual patients. Conclusions In the current organization of Belgian health care, a remote monitoring prenatal follow-up of women with GHD is cost saving for the global health care system, mainly via savings for the insurance institution RIZIV.

B4. Normal and abnormal blood pressures in early pregnancy: are we using the right cut off values?

Abstract Introduction: Subclinical hypertension has been reported in the first trimester of future hypertensive patients compared to normotensive patients. However, in clinical practice today, a cut off of 140/90 mmHg is still used to discriminate normotension from hypertension during pregnancy. We aim to investigate the most appropriate threshold for early gestational blood pressure values, which allow discriminating pregnant women between those at low or at high risk for gestational hypertensive diseases. Methods: Singleton pregnancies were included. A standard protocol was used to measure systolic (SBP), diastolic (DBP) and mean arterial pressure (MAP) in supine and standing position, by mode of an oscillometric sphygmomanometer around 12 weeks and 20 weeks of gestation. After delivery, gestational outcome was categorized in normotensive pregnancies (NP) or gestational hypertensive disease (GHD). ROC analysis was used to define the early gestational blood pressure cut off value with best possible performance in predicting GHD. Mann–Whitney U tests at nominal level a <0.05 were performed using SPSS for intergroup comparison. Results: A total of 780 women were measured at 12 weeks. Of these, 433 pregnant women were reevaluated around 20 weeks. At 12 and 20 weeks, blood pressures in GHD were higher than in NP (Table 1).Figure 1. (A) Boxplot NP versus GHD of DBP at 12 weeks, where redline indicates the threshold. (B) Boxplot UP versus GHD of DBP at 20 weeks with red line as threshold. Conclusions: Simple sphygmomanometric blood pressure measurements in standing position under standardized conditions at 12 weeks and 20 weeks has ≥96% negative predictive value for gestational hypertensive disease when DBP cut off is set at 81 and 78 mm Hg, respectively.

F2. Maternal body fluid composition in uncomplicated pregnancies and preeclampsia: a bioelectrical impedance analysis

Abstract Introduction: Body fluid composition (BFC) changes during the course of pregnancy and evidence is growing that these changes are different in uncomplicated pregnancies compared to hypertensive pregnancies. Methods: The aim of this study was to evaluate the changes in maternal BFC during the course of uncomplicated pregnancy (UP) using bioimpedance analysis, as a reference to measurements in hypertensive pregnancies. BFC was assessed using a multiple frequency bioelectrical impedance analyser. Five hundred and seventeen measurements were performed in 276 patients with UP. Single measurements were performed at diagnosis in 34 patients with gestational hypertension (GH), 35 with late onset preeclampsia (LPE) and 11 with early onset preeclampsia (EPE). Longitudinal linear mixed model based analysis and ANOVA with a post hoc Bonferroni was performed as appropriate. Results: Total body water (TBW), extracellular water (ECW) and ECW/ICW significantly increase during the course of pregnancy, whereas intracellular water (ICW) does not (Figure 1). Significant differences between uncomplicated pregnancies and the hypertensive groups are presented in Table 1 (mean ± standard deviation). Conclusions: BFC changes during the course of uncomplicated pregnancies and differs in and between hypertensive pregnancies.

NON-INVASIVE METHODS FOR MATERNAL CARDIAC OUTPUT MONITORING

In a non-obstetric population, the optimization of cardiac output (CO) had been shown to improve survival and to reduce postoperative complications, organ failure and the length of stay 1 . CO monitoring might be very useful in the obstetric population as well, as physiologic changes of CO during pregnancy are mandatory for a normal outcome. An uncomplicated pregnancy is associated with a 50% increase in maternal CO, which is mediated by plasma volume expansion and a decrease in peripheral resistance 2 . An aberrant change of this maternal CO might influence pregnancy outcome: pregnancies complicated with foetal growth restriction and/or preeclampsia are characterized by increased total vascular resistance and reduced systolic function (i.e. lower CO and stroke volume (SV)) 3 – 5 .