The Pulmonary Edema Preeclampsia Evaluation (PEPE) Study

Clinical value of mean platelet volume in predicting and diagnosing pre-eclampsia: a systematic review and meta-analysis

Background

Pre-eclampsia (PE) is a severe pregnancy complication. Thrombocytopenia and platelet dysfunction are common hematology disorders in PE. Previous studies considered mean platelet volume (MPV), a functional marker of platelets, as a potentially useful predictor for the diagnosis of PE.

Methods

PubMed, China Biomedical Literature Database, Chinese National Knowledge Infrastructure, Embase, Wanfang, VIP, and Cochrane Library databases were searched to gather diagnostic trials evaluating the diagnosis of PE using MPV, from their inception to 13 March 2023. We also searched Google Scholar and Baidu.

Results

A total of 22 studies from 20 articles were found. The pooled diagnostic accuracy of the MPV for PE recognition was as follows: sensitivity (SEN) 0.676 [95% confidence interval (CI) (0.658-0.694)], specificity (SPE) 0.710 [95% CI (0.703-0.717)], and diagnostic odds ratio (DOR) 7.012 [95% CI (4.226-11.636)], and the SROC-AUC and Q* indices were 0.7889 and 0.7262, respectively. The pooled SEN, SPE, and DOR of the diagnostic accuracy of MPV for PE before 16 weeks of gestation were 0.707 [95% CI (0.670-0.743)], 0.639 [95% CI (0.611-0.667)], and 4.026 [95% CI (2.727-5.943)], and the SROC-AUC and Q* indices were 0.7278 and 0.6753, respectively. For the interval of truncation values between 9 and 10 fl, the SROC-AUC and Q* indices for MPV were 0.8856 and 0.8162, respectively.

Conclusions

Available evidence suggests that MPV has a moderate predictive and diagnostic value for PE, particularly in diagnosing after 20 weeks of gestation. The diagnostic accuracy is higher when the MPV cut-off falls between 9 and 10 fl. The sensitivity of MPV alone in diagnosing PE is not high, and the combination of other markers for predictive diagnosis may better differentiate PE.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023425154, identifier: CRD42023425154.

Pulmonary oedema in the course of severe maternal outcome in South Africa: A cohort study combined with clinical audit

OBJECTIVES

To describe the incidence and outcomes of pulmonary oedema in women with severe maternal outcome during childbirth and identify possible modifiable factors through audit.

METHODS

All women with severe maternal outcome (maternal deaths or near misses) who were referred to Tygerberg referral hospital from health facilities in Metro East district, South Africa, during 2014-2015 were included. Women with severe maternal outcome and pulmonary oedema during pregnancy or childbirth were evaluated using three types of critical incident audit: criterion-based case review by one consultant gynaecologist, monodisciplinary critical incident audit by a team of gynaecologists, multidisciplinary audit with expert review from anaesthesiologists and cardiologists.

RESULTS

Of 32,161 pregnant women who gave birth in the study period, 399 (1.2%) women had severe maternal outcome and 72/399 (18.1%) had pulmonary oedema with a case fatality rate of 5.6% (4/72). Critical incident audit demonstrated that pre-eclampsia/HELLP-syndrome and chronic hypertension were the main conditions underlying pulmonary oedema (44/72, 61.1%). Administration of volumes of intravenous fluids in already sick women, undiagnosed underlying cardiac illness, administration of magnesium sulphate as part of pre-eclampsia management and oxytocin for augmentation of labour were identified as possible contributors to the pathophysiology of pulmonary oedema. Women-related factors (improved antenatal care attendance) and health care-related factors (earlier diagnosis and management) would potentially have improved maternal outcome.

CONCLUSIONS

Although pulmonary oedema in pregnancy is rare, among women with severe maternal outcome a considerable proportion had pulmonary oedema (18.1%). Audit identified options for prevention of pulmonary oedema and improved outcome. These included early detection and management of preeclampsia with close monitoring of fluid intake and cardiac evaluation in case of suspected pulmonary oedema. Therefore, a multidisciplinary clinical approach is recommended.

Cardiac magnetic resonance imaging in preeclampsia complicated by pulmonary edema shows myocardial edema with normal left ventricular systolic function

BACKGROUND

Preeclampsia complicates approximately 5% of all pregnancies. When pulmonary edema occurs, it accounts for 50% of preeclampsia-related mortality. Currently, there is no consensus on the degree to which left ventricular systolic dysfunction contributes to the development of pulmonary edema.

OBJECTIVE

This study aimed to use cardiac magnetic resonance imaging to detect subtle changes in left ventricular systolic function and evidence of acute left ventricular dysfunction (through tissue characterization) in women with preeclampsia complicated by pulmonary edema compared with both preeclamptic and normotensive controls.

STUDY DESIGN

Cases were postpartum women aged ≥18 years presenting with preeclampsia complicated by pulmonary edema. Of note, 2 control groups were recruited: women with preeclampsia without pulmonary edema and women with normotensive pregnancies. All women underwent echocardiography and 1.5T cardiac magnetic resonance imaging with native T1 and T2 mapping. Gadolinium contrast was administered to cases only. Because of small sample sizes, a nonparametric test (Kruskal-Wallis) with pairwise posthoc analysis using Bonferroni correction was used to compare the differences between the groups. Cardiac magnetic resonance images were interpreted by 2 independent reporters. The intraclass correlation coefficient was calculated to assess interobserver reliability.

RESULTS

Here, 20 women with preeclampsia complicated by pulmonary edema, 13 women with preeclampsia (5 with severe features and 8 without severe features), and 6 normotensive controls were recruited. There was no difference in the baseline characteristics between groups apart from the expected differences in blood pressure. Left atrial sizes were similar across all groups. Women with preeclampsia complicated by pulmonary edema had increased left ventricular mass (P=.01) but had normal systolic function compared with the normotensive controls. Furthermore, they had elevated native T1 values (P=.025) and a trend toward elevated T2 values (P=.07) in the absence of late gadolinium enhancement consistent with myocardial edema. Moreover, myocardial edema was present in all women with eclampsia or hemolysis, elevated liver enzymes, and low platelet count. Women with preeclampsia without severe features had similar findings to the normotensive controls. All cardiac magnetic resonance imaging measurements showed a very high level of interobserver correlation.

CONCLUSION

This study focused on cardiac magnetic resonance imaging in women with preeclampsia complicated by pulmonary edema, eclampsia, and hemolysis, elevated liver enzymes, and low platelet count. We have demonstrated normal systolic function with myocardial edema in women with preeclampsia with these severe features. These findings implicate an acute myocardial process as part of this clinical syndrome. The pathogenesis of myocardial edema and its relationship to pulmonary edema require further elucidation. With normal left atrial sizes, any hemodynamic component must be acute.

PROVE-Pre-Eclampsia Obstetric Adverse Events: Establishment of a Biobank and Database for Pre-Eclampsia

Pre-eclampsia is a leading cause of maternal and perinatal morbidity and mortality. The burden of disease lies mainly in low-middle income countries. The aim of this project is to establish a pre-eclampsia biobank in South Africa to facilitate research in the field of pre-eclampsia with a focus on phenotyping severe disease.The approach of our biobank is to collect biological specimens, detailed clinical data, tests, and biophysical examinations, including magnetic resonance imaging (MRI) of the brain, MRI of the heart, transcranial Doppler, echocardiography, and cognitive function tests.Women diagnosed with pre-eclampsia and normotensive controls are enrolled in the biobank at admission to Tygerberg University Hospital (Cape Town, South Africa). Biological samples and clinical data are collected at inclusion/delivery and during the hospital stay. Special investigations as per above are performed in a subset of women. After two months, women are followed up by telephonic interviews. This project aims to establish a biobank and database for severe organ complications of pre-eclampsia in a low-middle income country where the incidence of pre-eclampsia with organ complications is high. The study integrates different methods to investigate pre-eclampsia, focusing on improved understanding of pathophysiology, prediction of organ complications, and potentially future drug evaluation and discovery.

Renal and cardiovascular repercussions in preeclampsia and their impact on fluid management: a literature review

Preeclampsia is a multifactorial condition associated with significant morbidity and mortality. Fluid therapy in these patients is challenging since volume expansion may precipitate pulmonary edema, and fluid restriction may worsen renal function. Furthermore, cardiac impairment may introduce an additional component to the hemodynamic management. This article reviews the repercussions of preeclampsia on renal and cardiovascular systems and the development of pulmonary edema, as well as to discuss fluid management, focusing on the mitigation of adverse outcomes and monitoring alternatives. The literature review was carried out using PubMed, Embase, and Google Scholar databases from May 2019 to March 2020. Papers addressing the subjects of interest were included regardless of the publication language. There is a current trend towards restricting the administration of fluids in women with non-complicated preeclampsia. However, patients with preeclampsia may experience hemorrhagic shock, requiring volume resuscitation. In this case, hemodynamic monitoring is recommended to guide fluid therapy while avoiding complications.

Point-of-care lung ultrasound patterns in late third-trimester gravidas with and without preeclampsia

BACKGROUND

Transthoracic point-of-care ultrasonography of the lungs has become a standard technique in critical care medicine for the evaluation of patients with respiratory signs or symptoms but has not been well studied in pregnancy.

OBJECTIVE

To compare lung ultrasound patterns in third-trimester gravidas with and without preeclampsia and assess interobserver agreement between 3 obstetrical providers and a physician expert in critical care lung ultrasound.

STUDY DESIGN

This is a prospective observational study of 262 women with singleton pregnancies between 32 0/7 and 41 6/7 weeks' gestation. Lung ultrasound examinations were performed and interpreted by a team of obstetrical care providers and then interpreted by an expert in point-of-care lung ultrasound. The number of B-lines in each of the 4 lung fields, indicating the accumulation of fluid in the interstitial space and the alveoli, was evaluated. The primary outcome was a positive study for pulmonary interstitial edema, defined as an ultrasound study with 3 or more B-lines in 2 or more bilateral lung fields. The secondary outcome was a lung ultrasound study with 1 or 2 B-lines in 1 or more lung fields or 3 B-lines in 1 lung field. Interobserver agreement in lung ultrasound interpretation between obstetrical care providers and an expert in critical care point-of-care ultrasonography of the lung was assessed.

RESULTS

Among healthy gravidas, no subject had a lung ultrasound examination positive for pulmonary interstitial edema. Notably, 2 patients with preeclampsia had positive lung ultrasound studies, and both had respiratory symptoms or signs of pulmonary edema. One or 2 B-lines or 3 B-lines in 1 lung field were identified in 11.4% of healthy gravidas and 18.6% of patients with preeclampsia. There was no difference in lung ultrasound patterns between healthy gravidas and those with preeclampsia. The obstetrical care providers and the lung ultrasound expert had a high proportion of agreement regarding the interpretation of negative lung ultrasound examinations. The 2 patients with clinical signs of pulmonary edema were judged to have positive studies by both the obstetrical team and the expert; however, the obstetrical team classified more studies as positive.

CONCLUSION

Lung ultrasound patterns in women with preeclampsia without respiratory symptoms or clinical signs of pulmonary edema are similar to the lung ultrasound patterns of healthy gravidas. Point-of-care lung ultrasound can be used to evaluate third-trimester gravidas with preeclampsia and respiratory complaints or signs concerning for pulmonary edema. Formal training is important before the widespread adoption of point-of-care lung ultrasound by obstetrical healthcare providers.

Acute Cardiac Effects of Severe Pre-Eclampsia

BACKGROUND

Pre-eclampsia with severe features (PEC) is a pregnancy-specific syndrome characterized by severe hypertension and end-organ dysfunction, and is associated with short-term adverse cardiovascular events, including heart failure, pulmonary edema, and stroke.

OBJECTIVES

The authors aimed to characterize the short-term echocardiographic, clinical, and laboratory changes in women with PEC, focusing on right ventricular (RV) systolic pressure (RVSP) and echocardiographic-derived diastolic, systolic, and speckle tracking parameters.

METHODS

In this prospective observational study, the authors recruited 63 women with PEC and 36 pregnant control patients.

RESULTS

The PEC cohort had higher RVSP (31.0 ± 7.9 mm Hg vs. 22.5 ± 6.1 mm Hg; p < 0.001) and decreased global RV longitudinal systolic strain (RVLSS) (-19.6 ± 3.2% vs. -23.8 ± 2.9% [p < 0.0001]) when compared with the control cohort. For left-sided cardiac parameters, there were differences (p < 0.001) in mitral septal e' velocity (9.6 ± 2.4 cm/s vs. 11.6 ± 1.9 cm/s), septal E/e' ratio (10.8 ± 2.8 vs. 7.4 ± 1.6), left atrial area size (20.1 ± 3.8 cm² vs. 17.3 ± 2.9 cm²), and posterior and septal wall thickness (median [interquartile range]: 1.0 cm [0.9 to 1.1 cm] vs. 0.8 cm [0.7 to 0.9 cm], and 1.0 cm [0.8 to 1.2 cm] vs. 0.8 cm [0.7 to 0.9 cm]). Eight women (12.7%) with PEC had grade II diastolic dysfunction, and 6 women (9.5%) had peripartum pulmonary edema.

CONCLUSIONS

Women with PEC have higher RVSP, higher rates of abnormal diastolic function, decreased global RVLSS, increased left-sided chamber remodeling, and higher rates of peripartum pulmonary edema, when compared with healthy pregnant women.

Preeclampsia: Acute Complications and Management Priorities

Acute complications of preeclampsia contribute substantially to maternal and fetal morbidity and mortality. The considerable variation in onset, clinical presentation, and severity of this hypertensive disease that is unique to pregnancy creates challenges in identifying risk factors for clinical deterioration. Delivery of the fetus remains the only definitive treatment for preeclampsia. Surveillance of signs and symptoms and laboratory parameters consistent with progression in severity requires an appreciation of the dynamic and progressive nature of the disease. This article provides a comprehensive overview of the pathophysiology of preeclampsia, setting the foundation for discussion of management priorities for acute complications that pose the greatest risks to maternal health.

Adrenergic receptor blockade attenuates placental ischemia-induced hypertension

Preeclampsia (PE), a disorder of new-onset maternal hypertension and vascular dysfunction during pregnancy, is thought to be linked to placental ischemia-induced release of prohypertensive factors and reductions of vasoprotective factors in the maternal circulation. Although markers of sympathetic nervous activity are elevated in experimental models of placental ischemia-induced hypertension and women with PE compared with their normal pregnant counterparts, the importance of adrenergic receptor signaling in the development of hypertension in PE is unknown. Therefore, we tested the hypothesis that adrenergic receptor blockade attenuates the development of placental ischemia-induced hypertension in rats. Wistar Hannover rats underwent reduced uterine perfusion pressure (RUPP) or Sham surgeries on gestational day 14. By day 19, mean arterial blood pressure (MAP) was increased in RUPP over Sham rats. Groups of RUPP and Sham pregnant rats received terazosin and propranolol (3 mg/kg per day of each via subcutaneous osmotic minipump) to block α1- and β-adrenergic receptors, respectively, beginning on gestational day 14. Adrenergic blockade significantly attenuated the development of hypertension in the RUPP rats with a slight blood pressure-lowering response in the Sham, normal pregnant rats by day 19. In conclusion, these data implicate that placental ischemia-induced hypertension involves adrenergic receptor signaling to promote increases in blood pressure during PE.

Acute pulmonary edema in an obstetric intensive care unit: A case series study

Acute pulmonary edema (PE) affects 0.08% to 1.5% of women during pregnancy and in the postpartum. At the Instituto de Medicina Integral Prof. Fernando Figueira (IMIP), acute PE accounts for 1.5% of admissions to the obstetric intensive care unit (ICU) and occurs in 9.3% of the patients admitted with near miss criteria. This study was conducted to describe the clinical/epidemiological profile of patients with acute PE in IMIP's obstetric ICU.A case series of 50 patients with acute PE in an obstetric ICU in northeastern Brazil between August 2012 and March 2015. Frequency distribution and measures of central tendency/dispersion were calculated using Epi Info, version 7.1.5.The mean age of the women was 27.2 years; 60% were from Recife; 50% had 8 to 11 years of schooling; 54.0% were primigravidas. Acute PE occurred antepartum (58%), postpartum (38%), or intrapartum (4.0%). Overall, 8% had had previous episodes; 6% relapsed during hospitalization; 4% died. Caesarean sections were common (78.0%), with 73.3% delivering at <37 weeks and 39.0% at <34 weeks. Etiologies were hypertensive (62%), cardiogenic (16.0%), both hypertensive and cardiogenic (20.0%) or due to fluid overload (2.0%). Irrespective of etiology, in the 24 hours preceding acute PE, fluid overload was present in 34.0%. Median time from diagnosis until resuscitation maneuvers was 5 minutes (within 30 minutes of diagnosis in 75.0% of patients). Mean ICU time was 5 days and mean hospitalization time 11 days.Acute PE is a severe disease resulting in high maternal/perinatal morbidity/mortality rates. Most commonly, it occurred antepartum and associated with hypertension. Fluid overload appears to constitute an important trigger.

Role of endogenous digitalis-like factors in the clinical manifestations of severe preeclampsia: a sytematic review

Endogenous digitalis-like factor(s), originally proposed as a vasoconstrictor natriuretic hormone, was discovered in fetal and neonatal blood accidentally because it cross-reacts with antidigoxin antibodies (ADAs). Early studies using immunoassays with ADA identified the digoxin-like immuno-reactive factor(s) (EDLF) in maternal blood as well, and suggested it originated in the feto-placental unit. Mammalian digoxin-like factors have recently been identified as at least two classes of steroid compounds, plant derived ouabain (O), and several toad derived bufodienolides, most prominent being marinobufagenin (MBG). A synthetic pathway for MBG has been identified in mammalian placental tissue. Elevated maternal and fetal EDLF, O and MBG have been demonstrated in preeclampsia (PE), and inhibition of red cell membrane sodium, potassium ATPase (Na, K ATPase (NKA)) by EDLF is reversed by ADA fragments (ADA-FAB). Accordingly, maternal administration of a commercial ADA-antibody fragment (FAB) was tested in several anecdotal cases of PE, and two, small randomized, prospective, double-blind clinical trials. In the first randomized trial, ADA-FAB was administered post-partum, in the second antepartum. In the post-partum trial, ADA-FAB reduced use of antihypertensive drugs. In the second trial, there was no effect of ADA-FAB on blood pressure, but the fall in maternal creatinine clearance (CrCl) was prevented. In a secondary analysis using the pre-treatment maternal level of circulating Na, K ATPase (NKA) inhibitory activity (NKAI), ADA-FAB reduced the incidence of pulmonary edema and, unexpectedly, that of severe neonatal intraventricular hemorrhage (IVH). The fall in CrCl in patients given placebo was proportional to the circulating level of NKAI. The implications of these findings on the pathophysiology of the clinical manifestations PE are discussed, and a new model of the respective roles of placenta derived anti-angiogenic (AAG) factors (AAGFs) and EDLF is proposed.

Plasmatic levels of N-terminal pro-atrial natriuretic peptide in preeclamptic patients and healthy normotensive pregnant women

BACKGROUND AND OBJECTIVE

To compare plasma N-terminal pro-atrial natriuretic peptide concentrations in preeclamptic patients and healthy normotensive pregnant women.

METHODS

A cases-controls study was done with 180 patients at Hospital Central Dr. Urquinaona, Maracaibo, Venezuela, that included 90 preeclamptic patients (group A; cases) and 90 healthy normotensive pregnant women selected with the same age and body mass index similar to group A (group B; controls). Blood samples were collected one hour after admission and prior to administration of any medication in group A to determine plasma N-terminal pro-atrial natriuretic peptide and other laboratory parameters.

RESULTS

Plasma N-terminal pro-atrial natriuretic peptide concentrations in group A (mean 1.01 [0.26] pg/mL) showed a significant difference when compared with patients in group B (mean 0.55 [0.07] pg/mL; P<.001]. There was no significant correlation with systolic and diastolic blood pressure values in preeclamptic patients (P=ns). A cut-off value of 0.66ng/mL had an area under the curve of 0.93, sensitivity of 87.8%, specificity of 83.3%, a positive predictive value of 84.0% and a negative predictive value of 87.2%, with a diagnostic accuracy of 85.6%.

CONCLUSION

Preeclamptic patients have significantly higher concentrations of plasma N-terminal pro-atrial natriuretic peptide compared with healthy normotensive pregnant women, with high predictive values for diagnosis.

Severe maternal morbidity due to respiratory disease and impact of 2009 H1N1 influenza A pandemic in Brazil: results from a national multicenter cross-sectional study

BACKGROUND

The aim of this study was to assess the burden of respiratory disease, considering the influenza A pandemic season (H1N1pdm09), within the Brazilian Network for Surveillance of Severe Maternal Morbidity, and factors associated with worse maternal outcome.

METHODS

A multicenter cross-sectional study, involving 27 referral maternity hospitals in five Brazilian regions. Cases were identified in a prospective surveillance by using the WHO standardized criteria for potentially life-threatening conditions (PLTC) and maternal near miss (MNM). Women with severe complications from respiratory disease identified as suspected or confirmed cases of H1N1 influenza or respiratory failure were compared to those with other causes of severe morbidity. A review of suspected H1N1 influenza cases classified women as non-tested, tested positive and tested negative, comparing their outcomes. Factors associated with severe maternal outcome (SMO = MNM + MD) were assessed in both groups, in comparison to PLTC, using PR and 95 % CI adjusted for design effect of cluster sampling.

RESULTS

Among 9555 cases of severe maternal morbidity, 485 (5 %) had respiratory disease. Respiratory disease occurred in one-quarter of MNM cases and two-thirds of MD. H1N1 virus was suspected in 206 cases with respiratory illness. Around 60 % of these women were tested, yielding 49 confirmed cases. Confirmed H1N1 influenza cases had worse adverse outcomes (MNM:MD ratio < 1 (0.9:1), compared to 12:1 in cases due to other causes), and a mortality index > 50 %, in comparison to 7.4 % in other causes of severe maternal morbidity. Delay in medical care was associated with SMO in all cases considered, with a two-fold increased risk among respiratory disease patients. Perinatal outcome was worse in cases complicated by respiratory disease, with increased prematurity, stillbirth, low birth weight and Apgar score < 7.

CONCLUSIONS

Respiratory disease, especially considering the influenza season, is a very severe cause of maternal near miss and death. Increased awareness about this condition, preventive vaccination during pregnancy, early diagnosis and treatment are required to improve maternal health.

Fulminant antenatal pulmonary oedema in a woman with hypertension and superimposed preeclampsia

An asymptomatic 40-year-old para 1 black African woman with pre-existing hypertension and a booking blood pressure of 120/80 mm Hg, was admitted with superimposed preeclampsia diagnosed because of worsening hypertension and significant proteinuria at 27+5 weeks gestation. Antenatally, her blood pressure was controlled with labetalol, and blood tests including serum creatinine were within normal limits for pregnancy. Three days later, the patient developed severe hypertension despite treatment, and reported sudden onset severe shortness of breath; oxygen saturations on air dropped to 93%. Auscultation revealed widespread crepitations leading to a working diagnosis of pulmonary oedema. Despite appropriate management, respiratory function continued to deteriorate and she required intubation, ventilation and emergency caesarean section under general anaesthesia. A live male infant was delivered floppy and was intubated and resuscitated. He awaits discharge home on oxygen. The mother's pulmonary oedema resolved postpartum. Echocardiogram showed left ventricular hypertrophy but normal left ventricular function and the patient's hypertension is being controlled on medication.

Respiratory Failure and Mechanical Ventilation in the Pregnant Patient

Fewer than 2% of all peripartal patients need intensive care unit admission. But due to some anatomic and physiologic changes in pregnancy, respiratory failure can be promoted. This article reviews several obstetric and nonobstetric diseases that lead to respiratory failure and the treatment of these. Furthermore, invasive and noninvasive ventilation in pregnancy is discussed and suggestions of medication during ventilation are given.