A randomized trial of plasma volume expansion in hypertensive disorders of pregnancy: influence on the pulsatility indices of the fetal umbilical artery and middle cerebral artery

Prediction of fetal and neonatal outcomes after preterm manifestations of placental insufficiency: systematic review of prediction models

OBJECTIVES

To identify all prediction models for fetal and neonatal outcomes in pregnancies with preterm manifestations of placental insufficiency (gestational hypertension, pre-eclampsia, HELLP syndrome or fetal growth restriction with its onset before 37 weeks' gestation) and to assess the quality of the models and their performance on external validation.

METHODS

A systematic literature search was performed in PubMed, Web of Science and EMBASE. Studies describing prediction models for fetal/neonatal mortality or significant neonatal morbidity in patients with preterm placental insufficiency disorders were included. Data extraction was performed using the CHARMS checklist. Risk of bias was assessed using PROBAST. Literature selection and data extraction were performed by two researchers independently.

RESULTS

Our literature search yielded 22 491 unique publications. Fourteen were included after full-text screening of 218 articles that remained after initial exclusions. The studies derived a total of 41 prediction models, including four models in the setting of pre-eclampsia or HELLP, two models in the setting of fetal growth restriction and/or pre-eclampsia and 35 models in the setting of fetal growth restriction. None of the models was validated externally, and internal validation was performed in only two studies. The final models contained mainly ultrasound (Doppler) markers as predictors of fetal/neonatal mortality and neonatal morbidity. Discriminative properties were reported for 27/41 models (c-statistic between 0.6 and 0.9). Only two studies presented a calibration plot. The risk of bias was assessed as unclear in one model and high for all other models, mainly owing to the use of inappropriate statistical methods.

CONCLUSIONS

We identified 41 prediction models for fetal and neonatal outcomes in pregnancies with preterm manifestations of placental insufficiency. All models were considered to be of low methodological quality, apart from one that had unclear methodological quality. Higher-quality models and external validation studies are needed to inform clinical decision-making based on prediction models. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

EASL Clinical Practice Guidelines on the management of liver diseases in pregnancy

Liver diseases in pregnancy comprise both gestational liver disorders and acute and chronic hepatic disorders occurring coincidentally in pregnancy. Whether related to pregnancy or pre-existing, liver diseases in pregnancy are associated with a significant risk of maternal and fetal morbidity and mortality. Thus, the European Association for the Study of Liver Disease invited a panel of experts to develop clinical practice guidelines aimed at providing recommendations, based on the best available evidence, for the management of liver disease in pregnancy for hepatologists, gastroenterologists, obstetric physicians, general physicians, obstetricians, specialists in training and other healthcare professionals who provide care for this patient population.

The influence of fluid management on outcomes in preeclampsia: a systematic review and meta-analysis

BACKGROUND

The optimal fluid management strategy to ensure best outcomes in preeclamptic patients remains a controversial issue, with little evidence to support any one approach.

OBJECTIVE

The aim of this systematic review was to investigate the effect of various fluid management strategies on clinical outcomes, haemodynamic indices and biochemical markers in preeclamptic women and their babies. Primary outcome measures were the occurrence of pulmonary oedema and/or the development of renal impairment.

METHODS

A systematic review of randomised fluid management strategies was conducted. Five electronic databases were searched using the expanded search terms: 'intravenous fluid', 'plasma substitutes', 'intravenous fluid management', 'intravenous fluid therapy', plasma volume expansion', 'fluid restriction', 'oncotic therapy', 'crystalloids', 'colloids', 'preeclampsia', 'toxemia of pregnancy', 'pregnancy-induced hypertension', 'eclampsia' and 'gestational proteinuric hypertension'.

RESULTS

Six randomised controlled trials (RCTs), from nine publications, were included in the final analysis. There were no differences between groups with respect to the incidence of pulmonary oedema, perinatal mortality, preterm delivery and caesarean section. Colloid volume expansion was associated with a significantly lower systolic and diastolic blood pressure, but had no effect on heart rate or cardiac index. Data on systemic vascular resistance (SVR), serum atrial natriuretic peptide (ANP) and urine volume could not be aggregated.

CONCLUSION

Data on the ideal fluid strategy in women with preeclampsia is limited, and insufficient to make any strong recommendations. Further randomised controlled studies are needed to provide more evidence for which fluid management strategies are best suited to this heterogeneous patient group.

Prediction of complications in early-onset pre-eclampsia (PREP): development and external multinational validation of prognostic models

BACKGROUND

Unexpected clinical deterioration before 34 weeks gestation is an undesired course in early-onset pre-eclampsia. To safely prolong preterm gestation, accurate and timely prediction of complications is required.

METHOD

Women with confirmed early onset pre-eclampsia were recruited from 53 maternity units in the UK to a large prospective cohort study (PREP-946) for development of prognostic models for the overall risk of experiencing a complication using logistic regression (PREP-L), and for predicting the time to adverse maternal outcome using a survival model (PREP-S). External validation of the models were carried out in a multinational cohort (PIERS-634) and another cohort from the Netherlands (PETRA-216). Main outcome measures were C-statistics to summarise discrimination of the models and calibration plots and calibration slopes.

RESULTS

A total of 169 mothers (18%) in the PREP dataset had adverse outcomes by 48 hours, and 633 (67%) by discharge. The C-statistics of the models for predicting complications by 48 hours and by discharge were 0.84 (95% CI, 0.81-0.87; PREP-S) and 0.82 (0.80-0.84; PREP-L), respectively. The PREP-S model included maternal age, gestation, medical history, systolic blood pressure, deep tendon reflexes, urine protein creatinine ratio, platelets, serum alanine amino transaminase, urea, creatinine, oxygen saturation and treatment with antihypertensives or magnesium sulfate. The PREP-L model included the above except deep tendon reflexes, serum alanine amino transaminase and creatinine. On validation in the external PIERS dataset, the reduced PREP-S model showed reasonable calibration (slope 0.80) and discrimination (C-statistic 0.75) for predicting adverse outcome by 48 hours. Reduced PREP-L model showed excellent calibration (slope: 0.93 PIERS, 0.90 PETRA) and discrimination (0.81 PIERS, 0.75 PETRA) for predicting risk by discharge in the two external datasets.

CONCLUSIONS

PREP models can be used to obtain predictions of adverse maternal outcome risk, including early preterm delivery, by 48 hours (PREP-S) and by discharge (PREP-L), in women with early onset pre-eclampsia in the context of current care. They have a potential role in triaging high-risk mothers who may need transfer to tertiary units for intensive maternal and neonatal care.

TRIAL REGISTRATION

ISRCTN40384046 , retrospectively registered.

Development and validation of prediction models for risk of adverse outcomes in women with early-onset pre-eclampsia: protocol of the prospective cohort PREP study

BACKGROUND

Early-onset pre-eclampsia with raised blood pressure and protein in the urine before 34 weeks' gestation is one of the leading causes of maternal deaths in the UK. The benefits to the child from prolonging the pregnancy need to be balanced against the risk of maternal deterioration. Accurate prediction models of risks are needed to plan management.

METHODS

We aim to undertake a multicentre prospective cohort study (Prediction of Risks in Early onset Pre-eclampsia (PREP)) to develop clinical prediction models in women with early-onset pre-eclampsia, for risk of adverse maternal outcomes by 48 h and by discharge. We will externally validate the models in two independent cohorts with 634 and 216 women. In the secondary analyses, we will assess risk of adverse fetal and neonatal outcomes at birth and by discharge.

DISCUSSION

The PREP study will quantify the risk of maternal complications at various time points and provide individualised estimates of overall risk in women with early-onset pre-eclampsia to plan the management.

TRIAL REGISTRATION

ISRCTN registry, ISRCTN40384046.

Does low-molecular-weight heparin influence fetal growth or uterine and umbilical arterial Doppler in women with a history of early-onset uteroplacental insufficiency and an inheritable thrombophilia? Secondary randomised controlled trial results

OBJECTIVE

Does low-molecular-weight heparin (LMWH) added to low-dose aspirin influence fetal growth and flow velocity in uterine and umbilical arteries in women with an inheritable thrombophilia and previous early-onset uteroplacental insufficiency?

DESIGN

Secondary outcomes of the FRUIT-RCT.

SETTING

Multicentre, international.

POPULATION

The FRUIT-RCT included 139 women with inheritable thrombophilia before 12 weeks of gestation. Inclusion criteria were previous delivery before 34 weeks of gestation with a hypertensive disorder of pregnancy and/or small-for-gestational-age infant and an inheritable thrombophilia.

METHODS

After randomisation to either daily LMWH with aspirin, or aspirin only, ultrasound measurements were performed at 22-24, 28-30 and 34-36 weeks of gestation. Development during gestation of growth, birthweight and flow velocity of the umbilical artery was examined using the linear mixed model. Uterine artery flow velocity at a single time-point (22-24 weeks) was examined using a chi-square test.

MAIN OUTCOME MEASURES

Fetal growth over time including birthweight, using Scandinavian, Dutch and customised growth curves; and flow velocity within the uterine and umbilical arteries.

RESULTS

No difference of fetal growth over time could be demonstrated between the study arms, regardless of which reference criteria were used. The flow velocity within the uterine artery and umbilical artery did not differ between study arms.

CONCLUSION

The addition of LMWH to aspirin did not influence fetal growth or umbilical artery flow velocity over time; nor did it influence uterine artery flow velocity.

TWEETABLE ABSTRACT

LMWH does not influence fetal growth or uterine or umbilical flow velocities.

Predicting complications in pre-eclampsia: external validation of the fullPIERS model using the PETRA trial dataset

OBJECTIVE

The internally validated fullPIERS model predicts adverse maternal outcomes in women with pre-eclampsia within 48h after eligibility. Our objective was to assess generalizability of this prediction model.

STUDY DESIGN

External validation study using prospectively collected data from two tertiary care obstetric centers.

METHODS

The existing PETRA dataset, a cohort of women (n=216) with severe early-onset pre-eclampsia, eclampsia, HELLP syndrome or hypertension-associated fetal growth restriction was used. The fullPIERS model equation was applied to all women in the dataset using values collected within 48h after inclusion. The performance (ROC area and R-squared) of the model, risk stratification and calibration were assessed from 48h up to a week after inclusion.

RESULTS

Of 216 women in the PETRA trial, 73 (34%) experienced an adverse maternal outcome(s) at any time after inclusion. Adverse maternal outcome was observed in 32 (15%) cases within 48h and 62 (29%) within 7 days after inclusion. The fullPIERS model predicted adverse maternal outcomes within 48h (AUC ROC 0.97, 95% CI: 0.87-0.99) and up to 7 days after inclusion (AUC ROC 0.80, 95% CI: 0.70-0.87).

CONCLUSIONS

The fullPIERS model performed well when applied to the PETRA dataset. These results confirm the usability of the fullPIERS prediction model as a 'rule-in' test for women admitted with severe pre-eclampsia, eclampsia, HELLP syndrome or hypertension-associated fetal growth restriction. Future research should focus on intervention studies that assess the clinical impact of strategies using the fullPIERS model.

Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy

OBJECTIVE

This guideline summarizes the quality of the evidence to date and provides a reasonable approach to the diagnosis, evaluation and treatment of the hypertensive disorders of pregnancy (HDP).

EVIDENCE

The literature reviewed included the previous Society of Obstetricians and Gynaecologists of Canada (SOGC) HDP guidelines from 2008 and their reference lists, and an update from 2006. Medline, Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Registry of Controlled Trials (CCRCT) and Database of Abstracts and Reviews of Effects (DARE) were searched for literature published between January 2006 and March 2012. Articles were restricted to those published in French or English. Recommendations were evaluated using the criteria of the Canadian Task Force on Preventive Health Care and GRADE.

Severe pre-eclampsia and hypertensive crises

Hypertensive disorders of pregnancy are one of the leading causes of peripartum morbidity and mortality globally. Hypertensive disease in pregnancy is associated with a spectrum of severity, ranging from mild pregnancy-induced hypertension to eclampsia. Although most cases of pre-eclampsia may be managed successfully, severe pre-eclampsia is a life-threatening multisystem disease associated with eclampsia, HELLP (haemolysis, elevated liver enzymes, low platelets) syndrome, acute kidney injury, pulmonary oedema, placental abruption and intrauterine foetal death. Management of severe pre-eclampsia includes identification of high-risk patients, optimisation of antenatal care, early intervention and the identification and early management of complications. In the first instance, oral anti-hypertensive agents, including labetalol, nifedipine and methyldopa, should be tried. If oral anti-hypertensive agents have failed to adequately control blood pressure, intravenous anti-hypertensives should be considered. Commonly used intravenous anti-hypertensives include labetalol, hydralazine and glyceryl trinitrate. In addition to anti-hypertensive agents, close attention should be given to regular clinical examination, assessment of fluid balance, neurologic status and monitoring of other vital signs. Magnesium sulphate should be considered early to prevent seizures. Delivery of the baby is the definitive management of severe pre-eclampsia.

Increased Sympathetic Activity Present in Early Hypertensive Pregnancy is Not Lowered by Plasma Volume Expansion

OBJECTIVE

To evaluate whether sympathetic activity is increased in early-onset hypertensive pregnancy and whether this can be influenced by management with plasma volume expansion.

METHODS

The study group consisted of 74 subjects, of which 37 had early-onset hypertensive disorders of pregnancy (preeclampsia or gestational hypertension with fetal growth restriction), who were included at 24 to 34 weeks in a randomized controlled trial of management with (n = 18) or without (n = 19) plasma volume expansion. Heart rate and blood pressure variabilities, LF/HF ratio for heart rate, baroreflex sensitivity, and phase difference at low frequency (LF approximately 0.1 Hz) were calculated by spectral analysis from continuous heart rate and blood pressure recordings of the finger pulse wave (Portaprestrade mark, TNO). Measurements were performed at inclusion, after 20 to 40 hours and after 65 to 100 hours. The control group consisted of 29 women with a normal pregnancy and 8 women who had late-onset preeclampsia after 34 weeks. Controls were measured at 32 weeks. All controls had a normal blood pressures at that time.

RESULTS

LF variability of heart rate and blood pressure were significantly higher and baroreflex sensitivity was significantly lower in early-onset patients compared with normal controls. A significant trend towards higher LF variability of blood pressure and lower baroreflex sensitivity was found from normal controls to late-onset controls to early-onset patients. Parameters of sympathetic activity were not influenced by plasma volume expansion.

CONCLUSION

Sympathetic activity was increased in early-onset hypertensive pregnancy. However, this was not affected by management with plasma volume expansion, suggesting that hypovolaemia in preeclampsia is a secondary phenomenon.

Mean maternal second-trimester hemoglobin concentration and outcome of pregnancy: a population-based study

Both anemia and the lack of physiological maternal plasma volume expansion during the second trimester are associated with higher maternal morbidity and poor fetal outcome. Mean hemoglobin levels between the 14th and 30th gestational weeks were calculated in 4985 consecutive pregnant women and were correlated with outcome data of pregnancy. It was found that 9.4% of participants (n=3959) had normal pregnancy outcome. Mean maternal hemoglobin levels were significantly lower in women with a normal pregnancy (11.96+/-0.94 g/dL) compared with women who had adverse outcome events (preeclampsia, n=423, 12.5 +/- 1.0 g/dL, P< .0001; early birth, n=464, 12.2+/-1.01 g/dL, P< .0001; low birth weight newborn, n=473, 12.2+/-1.10 g/dL, P< .0001; intrauterine growth retardation, n=250, 12.2+/-1.0 g/dL, P< .0001). The risk for any adverse outcome event was lowest with a mean hemoglobin between 11.0 and 12.0 g/dL (odds ratio, 0.625; 95% confidence interval, 0.43-0.89) and highest between 13.0 and 15.0 g/dL (odds ratio, 2.24; 95% confidence interval, 1.54-3.31). In this population-based study from a community in Western Germany, impaired plasma volume expansion was an independent risk factor for the development of an adverse outcome of pregnancy.

Psychosocial impact of early-onset hypertensive disorders and related complications in pregnancy

OBJECTIVE

The objective of the study was to examine the psychosocial impact of severe hypertensive disorders during pregnancy.

STUDY DESIGN

All women (n = 216) in a prospective study cohort with severe hypertensive disorders of pregnancy were invited at term age, 3 months, and 1 year postterm to complete the 90-item Symptom Check List (SCL-90) questionnaire for assessment of their psychosocial condition. The association of hypothesized determinants was tested by binary logistic analysis.

RESULTS

Psychosocial impact decreased over time in all women (P < .01). Women with an adverse infant outcome had a worse score at term age (P = .04). The only parameter relating significantly to SCL-90 score in multivariate analysis was gestational age at inclusion. One year postterm, 72% resumed work and 9% were still on sick leave.

CONCLUSION

Severe hypertensive disorders of pregnancy have a high psychological impact, especially when gestational age at onset of disease is below 30 weeks or if adverse infant outcome occurs.

Dynamics and incidence patterns of maternal complications in early-onset hypertension of pregnancy

OBJECTIVE

To describe the variable disease expression and the patterns of development of major maternal morbidity and HELLP (haemolysis, elevated liver enzymes and low platelet count) syndrome in women with different subtypes of hypertensive disorders of pregnancy.

DESIGN

Prospective cohort study.

SETTING

Two university hospitals, tertiary care centres.

POPULATION

Two hundred and sixteen women participating in a randomised trial of temporising management in early-onset hypertensive disease (PETRA trial). Women were between 24 and 34 completed weeks and had either HELLP syndrome, severe pre-eclampsia, eclampsia or hypertension and fetal growth restriction. Women were delivered in the event of fetal marked heart rate abnormalities, pulmonary oedema, therapy-resistant hypertension or recurrent HELLP syndrome.

METHODS

Trial data were reanalysed to assess the time of onset of major maternal morbidity (e.g. pulmonary oedema, liver haematoma), HELLP syndrome and clinical disease. Associations between clinical parameters and prolongation of pregnancy were explored using logistic regression.

MAIN OUTCOME MEASURES

Diagnosis from admittance to discharge, major maternal morbidity and prolongation of pregnancy.

RESULTS

The median time to delivery or fetal death was 8.2 (range 0.1-44) days. At study entry, 56 women (26%) had more than one diagnosis; this increased to 171 women (79%) by the time of discharge. The incidence of major maternal morbidity (total 26) was 4.2% at 2-4 days after inclusion and a mean of 1.7% (range 0-2%) thereafter per time frame of 3 days. The mean incidence of new or recurrent HELLP syndrome episodes was 5.5% (range 1.9-8.7%) per time frame of 3 days during the first 3 weeks after inclusion.

CONCLUSIONS

Pre-eclampsia is a dynamic disease, with extensive overlap of subtypes of the syndrome. Prolongation of pregnancy in early-onset hypertensive disorders results in the development of further HELLP syndrome episodes and reversible major maternal morbidity but may improve perinatal healthy survival.

Prediction of maternal complications and adverse infant outcome at admission for temporizing management of early-onset severe hypertensive disorders of pregnancy

OBJECTIVE

We explored the association between clinical parameters at admission and the subsequent development of major maternal complications or adverse infant outcome in women with hypertensive complications of pregnancy remote from term.

STUDY DESIGN

We drew data from a randomized trial of temporizing management in 216 patients with hemolysis, elevated liver enzymes, and low platelets syndrome; severe preeclampsia; eclampsia; or hypertension-related fetal growth restriction and gestational ages between 24 and 34 completed weeks. End points were adverse infant outcome (perinatal death, severe morbidity) and major maternal complications (major morbidity; recurrent and newly acquired hemolysis, elevated liver enzymes, and low platelets; eclampsia) after admission. End point prevalences were comparable between the treatment and control groups. The association with age, parity, ethnicity, body mass index, gestational age, estimated fetal weight, blood pressure, antihypertensive medication, pulse rate, hemoglobin concentration, admitting center, diagnosis at inclusion, chronic hypertension, and thrombophilia was explored by logistic regression analysis.

RESULTS

Adverse infant outcome was predominantly influenced by gestational age (odds ratio 0.4 per week increment). Major maternal complications were correlated to multiparity (odds ratio 0.4) and estimated fetal weight (odds ratio 0.9 per 100-g increment).

CONCLUSION

Prediction at admission of the clinical course of the disease and the development of additional maternal complications was not feasible.

Transient Hypothyroxinemia in Severe Hypertensive Disorders of Pregnancy

OBJECTIVE

Assess whether and to what extent thyroid function is affected in pregnant women with early and severe hypertensive disorders and in their newborns.

METHODS

Patients were 80 women with preeclampsia, hemolysis, elevated liver enzymes, and low platelet count syndrome or gestational hypertension combined with fetal growth restriction in the 24th to 34th week of singleton pregnancies. Maternal thyroid hormone levels and thyroid peroxidase antibodies were determined at admission and 3 months postpartum. Neonatal levels were determined from cord blood at delivery. Maternal hypothyroxinemia was defined as free T(4) (fT(4)) value below 9 pM.

RESULTS

At admission 26 (33%) women in the study group had fT(4) levels below 9 pM, with spontaneous normalization during pregnancy. There were no statistically significant differences between thyroid hormone values in women in the study group and 10 normotensive pregnant women in their third trimester. Three months postpartum, 97.5% of patients had normal thyroid hormone levels. Thyroid peroxidase antibodies were elevated in 10% of women postpartum. Their infants, born at a median gestational age of 30 6/7 weeks, had lower cord blood fT(4) and thyroid-stimulating hormone values compared with preterm infants of the comparison group, appropriate for gestational age. Cord blood fT(4) had no correlation with gestational age or maternal fT(4), but there was a significant correlation of cord blood fT(4) with umbilical artery pH.

CONCLUSION

Women with severe hypertensive disorders of pregnancy may have transiently lower fT(4) levels, without evidence of a thyroid disorder. Their neonates have lower fT(4) levels at birth unrelated to maternal fT(4), but related to prenatal acidosis.

LEVEL OF EVIDENCE

II-2.

Plasma volume expansion for treatment of women with pre-eclampsia

BACKGROUND

Plasma volume is reduced amongst women with pre-eclampsia. This association has led to the suggestion that expanding the plasma volume might improve maternal and uteroplacental circulation, and so potentially improve outcome for both the woman and her baby.

OBJECTIVES

The aim of this review was to assess the effects of plasma volume expansion for the treatment of women with pre-eclampsia.

SEARCH STRATEGY

The register of trials maintained by the Cochrane Pregnancy and Childbirth Group, and the Cochrane Controlled Trials Register Issue 1 1999 were searched for trials meeting the selection criteria.

SELECTION CRITERIA

Randomised trials were included. Quasi-random designs were excluded. Participants were women with hypertension during pregnancy, with or without proteinuria. Women who were postpartum at trial entry were excluded. Interventions were any comparison of plasma volume expansion with no expansion, or of one plasma volume expander with another.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two reviewers. Discrepancies were resolved by discussion. There was no blinding of authorship or results.

MAIN RESULTS

Three trials involving 61 women were included in this review. All compared a colloid solution with no plasma volume expansion. For every outcome reported, the confidence intervals are very wide and cross the no effect line.

REVIEWER'S CONCLUSIONS

There is insufficient evidence for any reliable estimates of the effects of plasma volume expansion for women with pre-eclampsia.