Lung Ultrasound Predicts Interstitial Syndrome and Hemodynamic Profile in Parturients with Severe Preeclampsia

Pleural lung sliding quantification using a speckle tracking technology: A feasibility study on 30 healthy volunteers

INTRODUCTION

Speckle tracking technology quantifies lung sliding and detects lung sliding abolition in case of pneumothorax on selected ultrasound loops through the analysis of acoustic markers.

OBJECTIVES

We aimed to test the ability of speckle tracking technology to quantify lung sliding using a pleural strain value (PS).

METHODS

We performed a prospective study in 30 healthy volunteers in whom we assessed the pleural speckle tracking using ultrasound loops. Seven breathing conditions with and without non-invasive ventilation were tested. Two observers analyzed the ultrasound loops in four lung areas (anterior and posterior, left and right) and compared the obtained PS values. The first endpoint was to determine the feasibility of the PS measurement in different breathing conditions. The secondary endpoints were to assess the intra- and inter-observer's reliability of the measurement to compare PS values between anterior and posterior lung areas and to explore their correlations with the measured tidal volume.

RESULTS

We analyzed 1624 ultrasound loops from 29 patients after one volunteer's exclusion. Feasibility of this method was rated at 90.8 [95%CI: 89.6 - 92.4]%. The intra-observer reliability measured through Intraclass Correlation Coefficients was 0.96 [95%CI: 0.91-0.98] and 0.93 [95%CI: 0.86-0.97] depending on the operator. The inter-observer reliability was 0.89 [95%CI: 0.78-0.95]. The PS values were significantly lower in the anterior lung areas compared with the posterior areas in all breathing conditions. A weak positive correlation was found in all the lung areas when a positive end expiratory pressure was applied with r = 0.26 [95%CI: 0.12;0.39]; p < 0.01.

CONCLUSION

Speckle tracking lung sliding quantification with PS was applicable in most conditions with an excellent intra- and inter-observer reliability. More studies in patients under invasive mechanical ventilation are needed to explore the correlation between PS values of pleural sliding and tidal volumes.

CLINICAL REGISTRATION

NCT05415605.

Postpartum Weight Change Association With Readmission and Blood Pressure Trend Among Individuals With Hypertensive Disorders of Pregnancy

BACKGROUND

The aim of this study was to evaluate the association between early postpartum weight change and (1) hospital readmission and (2) 2-week blood pressure trajectory.

METHODS AND RESULTS

This retrospective study cohort included 1365 individuals with a hypertensive disorder of pregnancy enrolled in a postpartum hypertension remote monitoring program. Exposure was percentage weight change from delivery to first weight recorded within 10 days postpartum. We first modeled likelihood of hospital readmission within 8 weeks postpartum using logistic regression adjusting for age, race, insurance, type of hypertensive disorder of pregnancy, early body mass index, gestational weight gain, mode of delivery, and any discharge antihypertensive medications. We then performed case-control analysis additionally matching in a 1:3 ratio on breastfeeding, early body mass index, discharge on antihypertensive medications, and days between weight measurements. Both analytic approaches were repeated, limiting to readmissions attributable to hypertension or heart failure. Finally, we compared blood pressure trajectories over first 2 weeks postpartum. Individuals who did not lose weight in the early postpartum period had more admissions compared with weight loss groups (group 3: 14.1% versus group 2: 5.8% versus group 1: 4.5%). These individuals had 4 times the odds of postpartum readmissions (adjusted odds ratio [aOR], 3.9 [95% CI, 1.8-8.6]) to 7 (aOR, 7.8 [95% CI, 2.3-26.5]) compared with those with the most weight loss. This association strengthened when limited to hypertension or heart failure readmissions. These individuals also had more adverse postpartum blood pressure trajectories, with significant differences by weight change group.

CONCLUSIONS

Weight change is readily accessible and may identify individuals at high risk for postpartum readmission following a hypertensive disorder of pregnancy who could benefit from targeted interventions.

Point-of-Care Ultrasound in Critical Care Obstetrics: A Scoping Review of the Current Evidence

OBJECTIVES

To synthesize the current evidence of maternal point-of-care ultrasound (POCUS) in obstetrics. A scoping review was conducted using PubMed, Clinicaltrials.gov, and the Cochrane library from inception through October 2023.

METHODS

Studies were eligible for inclusion if they described the use of POCUS among obstetric or postpartum patients. Two authors independently screened all abstracts. Quantitative, qualitative, and mixed-methods studies were eligible for inclusion. Case reports of single cases, review articles, and expert opinion articles were excluded. Studies describing detailed maternal nonobstetric sonograms or maternal first trimester sonograms to confirm viability and rule out ectopic pregnancy were also excluded. Data were tabulated using Microsoft Excel and summarized using a narrative review and descriptive statistics.

RESULTS

A total of 689 publications were identified through the search strategy and 12 studies met the inclusion criteria. Nine studies evaluated the use of lung POCUS in obstetrics in different clinical scenarios. Lung ultrasound (LUS) findings in preeclampsia showed an excellent ability to detect pulmonary edema (area under the receiver operating characteristic 0.961) and findings were correlated with clinical evidence of respiratory distress (21 of 57 [37%] versus 14 of 109 [13%]; P = .001). Three studies evaluated abdominal POCUS, two of the inferior vena cava (IVC) to predict postspinal anesthesia hypotension (PSAH) and fluid receptivity and one to assess the rate of ascites in patients with preeclampsia. Patients with PSAH had higher IVC collapsibility (area under the curve = 0.950, P < .001) and, in patients with severe preeclampsia, there is a high rate of ascites (52%) associated with increased risk of adverse outcomes. There were no studies on the use of subjective cardiac POCUS.

CONCLUSION

POCUS use in the management of high-risk obstetrics has increased. LUS has been the most studied modality and appears to have a potential role in the setting of preeclampsia complicated by pulmonary edema. Cardiac and abdominal POCUS have not been well studied. Trials are needed to evaluate its clinical applicability, reliability, and technique standardization before widespread use.

[Maternal mortality due to hypertensive disorders in France, 2016-2018]

Between 2016 and 2018, 13 maternal deaths were due to hypertensive disorders. During this period, the maternal mortality ratio was 0.6/100 000 live births. Hypertensive disorders were responsible for 4.8% of maternal deaths during the first year, 5.1% up to 42 days postpartum and for 13.5% of direct maternal mortality. Maternal deaths due to hypertensive disorders increased close to signification (p=0.09) compared to the last triennium (MMR=0.2/100.000). Classification of the hypertensive disorders was: 5 severe preeclampsia, 3 eclampsia, 4 HELLP syndromes et 1 undefined hypertension. In five cases, a stroke was associated. Mode of delivery was a cesarean section when the hypertensive disorder started before the labour (8/13, 62%). Six women were older than 35years old and 5/12 were nulliparous. Among the 12 cases where place of birth was known, 5 were born foreigners. BMI was over 30 for 46%. Medical care were estimated non optimal in 11/13 of the cases. Among these deaths, 66% (8/12) seemed to be preventable versus 82% for the last period 2013-2015. The main causal factor of suboptimal management was inappropriate management by the obstetrical or anesthetist/intensive care squads, respectively: 3 lack of diagnosis, 8 delays for diagnosis and 5 underestimated severity. Four cases corresponded to inappropriate health care organization. This study offers the opportunity to stress major points to optimize medical management and health care organization facing hypertensive disorders during pregnancy.

The role of lung and cardiac ultrasound for cardiovascular hemodynamic assessment of women with preeclampsia

Preeclampsia remains the leading cause of maternal morbidity and mortality and is associated with abnormal body fluid homeostasis and cardiovascular dysfunction. Moreover, 2 distinct hemodynamic phenotypes have been described in preeclampsia, which might require different therapeutic approaches. Fluid restriction is mandatory in women at risk of pulmonary edema, whereas additional fluid administration may be required to correct tissue hypoperfusion in women with intravascular volume depletion. As clinical examination alone cannot discriminate among different hemodynamic patterns, optimal management of women with preeclampsia remains challenging. Noninvasive bedside ultrasound has become an important diagnostic and monitoring tool in critically ill patients, and it has been demonstrated that it can also be used in the monitoring of women with preeclampsia. Echocardiography in combination with lung ultrasound provides information on hemodynamic status, cardiac function, lung congestion, and fluid responsiveness and, therefore, could help clinicians identify women at higher risk of life-threatening complications. This review describes the cardiovascular changes in preeclampsia and provides an overview of the ultrasound methodologies that could be efficiently used for better hemodynamic assessment and management of women with preeclampsia.

Thoracic ultrasound use in hospitalized and ambulatory adult patients: a quantitative picture

INTRODUCTION AND OBJECTIVES

Thoracic ultrasound (TUS) has been established as a powerful diagnostic and monitoring tool in the Intensive Care Unit (ICU). However, studies outside the critical care setting are scarce. The aim of this study was to investigate the value of TUS for hospitalized or ambulatory community patients.

MATERIALS AND METHODS

This was a retrospective study conducted from 2016 to 2020 in the TUS clinic at Heraklion University Hospital. TUS examination was performed using a standard ultrasound machine (EUB HITACHI 8500), and a high-frequency microconvex probe (5-8 MHz). Patients had been referred by their primary physician to address a range of different questions. The various respiratory system entities were characterised according to internationally established criteria.

RESULTS

762 TUS studies were performed on 526 patients due to underlying malignancy (n = 376), unexplained symptoms/signs (n = 53), pregnancy related issues (n = 42), evaluation of abnormal findings in X-ray (n = 165), recent surgery/trauma (n = 23), recent onset respiratory failure (n = 12), acute respiratory infection (n = 66) and underlying non-malignant disease (n = 25). Pleural effusion was the commonest pathologic entity (n = 610), followed by consolidation (n = 269), diaphragmatic dysfunction/paradox (n = 174) and interstitial syndrome (n = 53). Discrepancies between chest X-ray and ultrasonographic findings were demonstrated in 96 cases. The TUS findings guided invasive therapeutic management in 448 cases and non-invasive management in 43 cases, while follow-up monitoring was decided in 271 cases.

CONCLUSIONS

This study showed that TUS can identify the most common respiratory pathologic entities encountered in hospitalized and community ambulatory patients, and is especially useful in guiding the decision making process in a diverse group of patients.

Evaluation of extravascular lung water and cardiac function in normal vaginal delivery by intrapartum bedside ultrasound

BACKGROUND

Healthy parturients may experience pulmonary edema and disturbed cardiac function during labor. We aimed to evaluate the extravascular lung water (EVLW), intravascular volume, and cardiac function of normal parturients during spontaneous vaginal delivery by bedside ultrasound. And to explore the correlation between EVLW and intravascular volume, cardiac function.

METHODS

This was a prospective observational study including 30 singleton-term pregnant women undergoing spontaneous vaginal delivery. Bedside ultrasound was performed at the early labor, the end of the second stage of labor, 2 and 24 h postpartum, and 120 scanning results were recorded. EVLW was evaluated by the echo comet score (ECS) obtained by the 28-rib interspaces technique. Inferior vena cava collapsibility index (IVC-CI), left ventricle ejection fraction, right ventricle fractional area change, left and right ventricular E/A ratio, and left and right ventricular index of myocardial performance (LIMP and RIMP) were measured. Measurements among different time points were compared, and the correlations between ECS and other measurements were analyzed.

RESULTS

During the spontaneous vaginal delivery of healthy pregnant women, 2 had a mild EVLW increase at the early labor, 8 at the end of the second stage of labor, 13 at 2 h postpartum, and 4 at 24 h postpartum (P < 0.001). From the early labor to 24 h postpartum, ECS first increased and then decreased, reaching its peak at 2 h postpartum (P < 0.001). IVC-CI first decreased and then increased, reaching its minimum at the end of the second stage of labor (P < 0.001). RIMP exceeded the cut-off value of 0.43 at the end of the second stage of labor. ECS was weakly correlated with IVC-CI (r=-0.373, P < 0.001), LIMP (r = 0.298, P = 0.022) and RIMP (r = 0.211, P = 0.021).

CONCLUSIONS

During spontaneous vaginal delivery, the most vital period of perinatal care is between the end of the second stage of labor and 2 h postpartum, because the risk of pulmonary edema is higher and the right ventricle function may decline. IVC-CI can be used to evaluate maternal intravascular volume. The increase in EVLW may be related to the increase in intravascular volume and the decrease in ventricular function.

Incidence of Interstitial Alveolar Syndrome on Point-of-Care Lung Ultrasonography in Pre-eclamptic Women With Severe Features: A Prospective Observational Study

BACKGROUND

Lung interstitial edema is a clinically silent pathology that develops before overt pulmonary edema among pre-eclamptic women with severe features. Point-of-care lung ultrasonography (LUS) has been suggested as an accessible bedside tool that may identify lung interstitial edema before developing clinical signs and symptoms. Thus, we planned to use bedside LUS as a diagnostic tool in admitted pre-eclamptic women with severe features, with the aim of identifying alveolar-interstitial fluid, seen as B-lines. Our primary objective was to assess the incidence of interstitial alveolar syndrome on lung ultrasonography.

METHODS

We conducted a prospective, single-center, observational study on parturients with pre-eclampsia with severe features over a period of 15 months. LUS in 4 intercostal spaces (ICS) was performed on all eligible patients. The number of single or confluent B-lines in each space was recorded by an independent observer. A scoring system was used to grade the lung fluid content based on the number of single and confluent B-lines per ICS, with scores ranging from 0 to 32 (low, 0-10; moderate, 11-20; and high, 21+). The incidence of B-lines at admission and before and after delivery was calculated. In addition, bedside 2D echocardiography was performed to assess left ventricular systolic and diastolic function. Any correlation between presence of B-lines on LUS and blood pressure, clinical symptoms, or echocardiography findings was assessed.

RESULTS

Seventy patients were enrolled in the study. On LUS, B-lines were seen in 64.3% patients at admission (45/70 vs 25/70 without B-lines; P = .02), 65.7% patients before delivery (46/70 vs 24/70 without B-lines; P = .01), and 58.6% patients 24 hours postpartum (41/70 versus 29/70 without B-lines; P = .15). Nearly all patients (94.3%) exhibited low to moderate severity of pulmonary fluid burden at admission. Echocardiography revealed diastolic dysfunction in 47.1% (n = 33/70) patients with associated B-lines in the majority (n = 32/33). The total B-line score and E/e' ratio among patients with diastolic dysfunction was found to be strongly correlated (r = 0.848; P < .001). All pre-eclamptic women with presence of breathlessness (11/11; 100%) and facial puffiness (16/16; 100%) on admission had B-lines on LUS.

CONCLUSIONS

We conclude that ultrasonographic pulmonary interstitial syndrome is present in more than half of the women with pre-eclampsia with severe features and correlates with diastolic dysfunction, high blood pressure records, and acute-onset breathlessness.

Optic nerve sheath diameter measurements using ultrasonography to diagnose raised intracranial pressure in preeclampsia: an observational study

Objective

To estimate the incidence of raised intracranial pressure (ICP) as evident by enlarged optic nerve sheath diameter (ONSD) by ocular ultrasound among patients with preeclampsia and its relationship to severity of disease.

Material and Methods

Sixty pregnant mothers with preeclampsia were compared to 30 normotensive, uncomplicated pregnant controls. For ONSD measurement, a 7-MHZ linear probe was used and three values from each optic nerve were taken and the mean of six values of both eyes was recorded. All study subjects were followed until seven days after delivery.

Results

Two cut off values (5.8 mm and 4.6 mm) were used to compare ONSD in severe and non-severe preeclampsia with that of healthy pregnant individuals. The incidence of raised ICP among severe preeclampsia above 5.8 mm and 4.6 mm cut-off were 43.3% and 90%, respectively, before delivery. ONSD was significantly elevated among preeclampsia subjects at both cut-off values at pre-delivery (p=0.004 for ONSD >5.8 mm and p<0.001 for ONSD >4.6 mm) compared to controls. There a significant association between presence of neurological manifestations and enlarged ONSD (p<0.001 for ONSD >5.8 mm and p=0.04 for ONSD >4.6 mm) before delivery.

Conclusion

Severe preeclampsia with neurological features was associated with increased ONSD, reflecting raised ICP. Further studies are needed to compare ONSD values with invasive ICP monitoring for better understanding of this relationship.

Spirometry profiles among pregnant and non-pregnant African women: a cross-sectional study

BACKGROUND

Spirometry is a commonly used lung function test. It assesses respiratory functions by measuring the air volume and the rate at which a person can exhale from lungs filled to their total capacity. The most helpful spirometry parameters are: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and peak expiratory flow (PEF). Pregnancy derives an altered physiological state due to hormonal and anatomical changes that affect the respiratory system. Despite that, spirometry is less commonly done during pregnancy, and if done, test results are evaluated against non-pregnancy references.

OBJECTIVE

This study aimed to explore spirometry profiles in pregnant and non-pregnant women and describe their differences.

METHODOLOGY

This cross-sectional study involved age-matched pregnant and non-pregnant participants recruited from Mnazi Moja ANC and Muhimbili University (MUHAS). A digital spirometer was used to assess respiratory function. Data were entered and analyzed using SPSS version 23. The mean spirometry values of pregnant participants were compared to those of non-pregnant participants using an independent sample t-test. A p-value of < 0.05 was considered statistically significant.

RESULTS

The study included 92 pregnant and 98 non-pregnant participants subjected to spirometry. Both FVC and FEV1 values were significantly lower in pregnant than in non-pregnant participants (2.7 ± 0.5 L vs. 2.9 ± 0.5 L; p < 0.01 and 2.2 ± 0.4 L vs. 2.5 ± 0.4 L; p < 0.01 respectively). In addition, pregnant participants had significantly lower mean PEF values than their non-pregnant counterparts (303 ± 84 L/min versus 353 ± 64 L/min; p < 0.01).

CONCLUSION

Spirometry test values are lower in pregnancy than in non-pregnant participants.

RECOMMENDATIONS

Interpreting the spirometry test values of pregnant women using references obtained from non-pregnant women may be inappropriate. Future studies should evaluate the appropriateness of predicting spirometry values of pregnant women using reference equations derived from non-pregnant women.

Lung Inflammation Is Associated with Preeclampsia Development in the Rat

Preeclampsia (PE) is an obstetric complication associated with significant health implications for the fetus and mother. Studies have shown a correlation between lung disease development and PE. Gas6 protein is expressed in the lung and placenta, and binds to the AXL Tyrosine kinase receptor. Recently, our laboratory utilized Gas6 to induce preeclamptic-like conditions in rats. Our objective was to determine the role of Gas6/AXL signaling in the maternal lung during PE development. Briefly, pregnant rats were divided into control, Gas6, or Gas6 + R428 (an AXL inhibitor). Immunofluorescence was performed to determine AXL expression. Bronchoalveolar lavage fluid (BALF) was procured for the assessment of inflammatory cell secretion. Western blot was performed to detect signaling molecules and ELISA determined inflammatory cytokines. We observed increased proteinuria and increased blood pressure in Gas6-treated animals. AXL was increased in the lungs of the treated animals and BALF fluid revealed elevated total protein abundance in Gas6 animals. Extracellular-signal regulated kinase (ERK) and protein kinase B (AKT) signaling in the lung appeared to be mediated by Gas6 as well as the secretion of inflammatory cytokines. We conclude that Gas6 signaling is capable of inducing PE and that this is associated with increased lung inflammation.

Preeclampsia in 2021-a Perioperative Medical Challenge for the Anesthesiologist

The authors provide a review of recent advances in the understanding of pathophysiology and perioperative management of preeclampsia and eclampsia, from the perspective of the anesthesiologist. This review includes aspects of assessment of severity of disease, hemodynamic monitoring, peripartum anesthesia care, and postpartum management. The perioperative management of patients with eclampsia is also discussed.

Point-of-Care Ultrasound (POCUS) for the assessment of volume status and fluid management in patients with severe pre-eclampsia: A systematic review and meta-analysis

BACKGROUND AND AIMS

Appropriate volume assessment and fluid management can prevent maternal deaths in the severely pre-eclamptic (SPE) parturients. We planned a systematic review and meta-analysis (MA) to evaluate the role and ability of point-of-care ultrasound (POCUS) in the assessment of volume status and early detection of lung oedema in an SPE parturient.

METHODS

An e-literature search was done from several databases. Data were extracted under five domains including POCUS-derived parameters like echo comet score (ECS), lung ultrasound (LUS) scores, B-patterns, optic nerve sheath diameter (ONSD), E/e' ratio, presence of pleural effusion, pulmonary interstitial syndrome and pulmonary congestion. The risk of bias was assessed. Extracted data were analysed using MetaXL and Revman 5.3. Heterogeneity in the studies was evaluated using the Cochrane Q test and I2 statistics. Funnel plots were used for the assessment of publication bias.

RESULTS

Seven prospective studies including 574 parturients (including 396 pre-eclamptics) were selected. POCUS included lung, optic nerve, cardiac and thoracic US. In two studies, the ECS and LUS scores pre-delivery were higher in pre-eclamptics. Two studies found a mean ONSD of 5-5.84 mm before delivery. MA revealed a significantly lower mean ECS score at post-delivery than pre-delivery, and the summary prevalence of B-pattern and pleural effusion among SPE parturients was found to be 0.28 (0.03-0.84) and 0.1 (0-0.2), respectively. A good correlation was observed between B-line patterns and diastolic dysfunction (increased E/e' ratio), LUS score and thoracic fluid content, ONSD and ECS in individual studies.

CONCLUSION

POCUS parameters can be useful as early markers of fluid status and serve as useful tools in the precise clinical management of pre-eclampsia.

Guidelines for the management of women with severe pre-eclampsia

OBJECTIVE

To provide national guidelines for the management of women with severe pre-eclampsia.

DESIGN

A consensus committee of 26 experts was formed. A formal conflict-of-interest (COI) policy was developed at the onset of the process and enforced throughout. The entire guidelines process was conducted independently of any industrial funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasised.

METHODS

The last SFAR and CNGOF guidelines on the management of women with severe pre-eclampsia were published in 2009. The literature is now sufficient for an update. The aim of this expert panel guidelines is to evaluate the impact of different aspects of the management of women with severe preeclampsia on maternal and neonatal morbidities separately. The experts studied questions within 7 domains. Each question was formulated according to the PICO (Patients Intervention Comparison Outcome) model and the evidence profiles were produced. An extensive literature review and recommendations were carried out and analysed according to the GRADE® methodology.

RESULTS

The SFAR/CNGOF experts panel provided 25 recommendations: 8 have a high level of evidence (GRADE 1+/-), 9 have a moderate level of evidence (GRADE 2+/-), and for 7 recommendations, the GRADE method could not be applied, resulting in expert opinions. No recommendation was provided for 3 questions. After one scoring round, strong agreement was reached between the experts for all the recommendations.

CONCLUSIONS

There was strong agreement among experts who made 25 recommendations to improve practices for the management of women with severe pre-eclampsia.

Sonographic Evaluation of Pulmonary Interstitial Edema in Patient With Preeclampsia

ABSTRACT

The aim of this study was to sonographically detect pulmonary edema, which is a major problem in pregnant women with preeclampsia, in the interstitial phase. We evaluated 41 preeclampsia patients and 21 control subjects prospectively. In the preeclampsia group, 26 patients had severe features, whereas the other 15 patients had none. To detect early fluid loading in lungs, sonographic B lines were counted from the intercostal space by using ultrasonography, and left ventricular loading findings were examined for corporation by using transthoracic echocardiography both before and after birth. In severe preeclampsia, the number of B lines before and after birth is statistically significant compared with the other groups. In addition, the total number of B lines calculated at 24 hours after delivery was significantly lower than that calculated before delivery (P < 0.018). In terms of prenatal E values, a statistically significant difference was found between all groups (P < 0.001). A strong positive and statistically significant relationship was found between B lines and prenatal E/e' (r = 0.768; P < 0.001). The overall accuracy rate of the prenatal E/e' and E value for estimation of the B line number classification is 0.791 (95% confidence interval, 0.674-0.908; P < 0.001) and 0.829 (95% confidence interval, 0.722-0.936; P < 0.001), respectively. Pulmonary edema is a serious complication in patients with severe preeclampsia and may be detected interstitially in some patients, even if it does not occur clinically.

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 Pattern in Healthy Parturients: Prevalence of Pulmonary Interstitial Syndrome Following Vaginal Delivery, Elective and Unplanned Intrapartum Cesarean Delivery

BACKGROUND

Pregnancy-related cardiovascular physiologic changes increase the likelihood of pulmonary edema, with the risk of fluid extravasating into the pulmonary interstitium being potentially at a maximum during the early postpartum period. Data on the impact of labor and peripartum hemodynamic strain on lung ultrasound (LUS) are limited, and the prevalence of subclinical pulmonary interstitial syndrome in peripartum women is poorly described. The primary aim of this exploratory study was to estimate the prevalence of pulmonary interstitial syndrome in healthy term parturients undergoing vaginal (VD), elective (eCD), and unplanned intrapartum cesarean deliveries (uCD). Secondary aims were to estimate the prevalence of positive lung regions (≥3 B-lines on LUS per region) and to assess the associations between positive lung regions and possible contributing factors.

METHODS

In this prospective observational cohort study, healthy women at term undergoing VD, eCD, or uCD were enrolled. Following international consensus recommendations, a LUS examination was performed within 4 hours after delivery applying an 8-region technique. Pulmonary interstitial syndrome was defined by the presence of 2 or more positive lung regions per hemithorax. Ultrasound studies were reviewed by 2 blinded reviewers and assessed for interobserver reliability.

RESULTS

Seventy-five women were assessed (n = 25 per group). No pulmonary interstitial syndrome was found in the VD and eCD groups (each 0 of 25; 0%, 95% confidence interval [CI], 0-13.7). Pulmonary interstitial syndrome was found in 2 of 25 (8%, 95% CI, 1-26) women undergoing an uCD (P = .490 for VD versus uCD and P = .490 for eCD versus uCD). In 1 woman, this correlated clinically with the development of pulmonary edema. One or more positive lung regions were present in 5 of 25 (20%), 6 of 25 (24%), and 11 of 25 (44%) parturients following VD, eCD, and uCD, respectively (P = .136). Positive lung regions were predominantly found in lateral lung regions. The number of positive lung regions showed a weak correlation with patient age (r = 0.25, 95% CI, 0.05-0.47; P = .033). No significant association was found between LUS pattern and parity, duration of labor, labor augmentation, labor induction, estimated total intravenous fluid intake, or net intravenous fluid intake.

CONCLUSIONS

Although many focal areas of increased extravascular lung water (20%-44% prevalence) can be identified on LUS, the overall prevalence of pulmonary interstitial syndrome was 2.7% (2 of 75; 95% CI, 0.3-9.3) among healthy term parturients soon after delivery. Focal areas of positive lung water regions were weakly correlated with maternal age.

Lung Ultrasound Findings in the Postanesthesia Care Unit Are Associated With Outcome After Major Surgery: A Prospective Observational Study in a High-Risk Cohort

BACKGROUND

Postoperative pulmonary complications are associated with increased morbidity. Identifying patients at higher risk for such complications may allow preemptive treatment.

METHODS

Patients with an American Society of Anesthesiologists (ASA) score >1 and who were scheduled for major surgery of >2 hours were enrolled in a single-center prospective study. After extubation, lung ultrasound was performed after a median time of 60 minutes by 2 certified anesthesiologists in the postanesthesia care unit after a standardized tracheal extubation. Postoperative pulmonary complications occurring within 8 postoperative days were recorded. The association between lung ultrasound findings and postoperative pulmonary complications was analyzed using logistic regression models.

RESULTS

Among the 327 patients included, 69 (19%) developed postoperative pulmonary complications. The lung ultrasound score was higher in the patients who developed postoperative pulmonary complications (12 [7-18] vs 8 [4-12]; P < .001). The odds ratio for pulmonary complications in patients who had a pleural effusion detected by lung ultrasound was 3.7 (95% confidence interval, 1.2-11.7). The hospital death rate was also higher in patients with pleural effusions (22% vs 1.3%; P < .001). Patients with pulmonary consolidations on lung ultrasound had a higher risk of postoperative mechanical ventilation (17% vs 5.1%; P = .001). In all patients, the area under the curve for predicting postoperative pulmonary complications was 0.64 (95% confidence interval, 0.57-0.71).

CONCLUSIONS

When lung ultrasound is performed precociously <2 hours after extubation, detection of immediate postoperative alveolar consolidation and pleural effusion by lung ultrasound is associated with postoperative pulmonary complications and morbi-mortality. Further study is needed to determine the effect of ultrasound-guided intervention for patients at high risk of postoperative pulmonary 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.

The effect of vitamin C on pulmonary oedema in patients with severe preeclampsia: A single-centre, randomised, placebo-controlled, double-blind trial

OBJECTIVE

To determine whether vitamin C in the first three days postpartum reduces pulmonary oedema (PE) assessed by lung ultrasound in patients with severe preeclampsia.

DESIGN

Randomised, placebo-controlled, double-blind trial.

SETTING

Tertiary perinatal centre.

POPULATION

Consecutively admitted patients with singleton pregnancies complicated by severe preeclampsia.

METHODS

Thirty-four patients received vitamin C (1.5 g/6 h) (n = 17) or placebo (n = 17) at days 1, 2, and 3 postdelivery. Mann-Whitney-U test was used to compare vitamin C vs placebo groups. A p ≤ 0.05 was considered statistically significant.

MAIN OUTCOME MEASURES

Lung ultrasound was performed once daily in the first three days following delivery. Echo Comet Score (ECS) on day 1 postdelivery was the primary outcome studied and was obtained using the 28-rib interspaces technique. ECS on days 2 and 3 postdelivery were secondary outcomes.

RESULTS

There was no significant difference in ECS on day 1 (median 23 (inter-quartile range (IQR) 21-61) vs 18 (IQR 8-35); p = 0.31). All ultrasound examinations on day 1 were performed within six hours from delivery. On days 2 and 3, ECS was significantly lower in vitamin C group compared to placebo (8 (IQR 3-14) vs 35 (IQR 15-78); p = 0.03 and 5 (IQR 3-10) vs 18 (IQR 18-44); p = 0.04, respectively).

CONCLUSION

A single dose of intravenous vitamin C did not reduce PE in postpartum patients with severe preeclampsia on day 1 after delivery. Repeated doses, however, seem to have a delayed effect with a reduction in PE detected on ultrasound on days 2 and 3 following delivery.

TRIAL REGISTRATION

This trial is registered at ClinicalTrials.gov: ID NCT03451266 (https://clinicaltrials.gov/ct2/show/NCT03451266?term=NCT03451266&draw=2&rank=1).

Diagnostic performance of pulmonary ultrasonography and a clinical score for the evaluation of fluid overload in haemodialysis patients

INTRODUCTION

There is no feasible benchmark in daily routine to estimate the hydration status of haemodialysis patients, which is essential to their management.

OBJECTIVE

We performed a study in haemodialysis patients to assess the diagnostic performance of pulmonary ultrasound and clinical examination for the evaluation of fluid overload using transthoracic echocardiography as a gold standard.

METHODS

Thirty-one patients receiving chronic haemodialysis patients were included. Evaluation of hydration status was assessed weekly before haemodialysis sessions using clinical and Echo Comet Score from pulmonary ultrasound and transthoracic echocardiography (reference method).

RESULTS

Five patients had a transthoracic echocardiography overload. Compared with transthoracic echocardiography, the diagnostic performance of the clinical overload score has a sensitivity of 100%, a specificity of 77%, a positive predictive value of 50% and a negative predictive value of 100% with a κ of 0.79. Only orthopnoea (P=0.008), jugular turgor (P=0.005) and hepatic-jugular reflux (P=0.008) were significantly associated with transthoracic echocardiography overload diagnosis. The diagnostic performance of Echo Comet Score by pulmonary ultrasound has a sensitivity of 80%, a specificity of 58%, a positive predictive value of 26% and a negative predictive value of 94%. Ten patients (32.3%) had an increase of extravascular pulmonary water without evidence of transthoracic echocardiography or clinical overload.

CONCLUSIONS

Our clinical score has a convincing diagnostic performance compared to transthoracic echocardiography and could be easily used in daily clinical routine to adjust dry weight. The evaluation of the overload using pulmonary ultrasound seems poorly correlated with the overload evaluated by transthoracic echocardiography. Extravascular pulmonary water undetected by clinical examination and transthoracic echocardiography remains a parameter that requires further investigation.

Hypoxaemia during tracheal intubation in patients with hypertensive disorders of pregnancy: analysis of data from an obstetric airway management registry

BACKGROUND

In South Africa, hypertensive disorders of pregnancy are the leading cause of maternal mortality. More than 50% of anaesthesia-related maternal deaths are attributed to complications of airway management. We compared the prevalence and risk factors for hypoxaemia during induction of general anaesthesia in parturients with and without hypertensive disorders of pregnancy. We hypothesised that hypertensive disorders of pregnancy are associated with desaturation during tracheal intubation.

METHODS

Data from 402 cases in a multicentre obstetric airway management registry were analysed. The prevalence of peri-induction hypoxaemia (SpO₂ <90%) was compared in patients with and without hypertensive disorders of pregnancy. Quantile regression of SpO₂ nadir was performed to identify confounding variables associated with, and mediators of, hypoxaemia.

RESULTS

In the cohort of 402 cases, hypoxaemia occurred in 19% with and 9% without hypertension (estimated risk difference, 10%; 95% CI 2% to 17%; P=0.005). Quantile regression demonstrated a lower SpO₂ nadir associated with hypertensive disorders of pregnancy as body mass index increased. Room-air oxygen saturation, Mallampati grade, and number of intubation attempts were associated with the relationship.

CONCLUSIONS

Clinically significant oxygen desaturation during airway management occurred twice as often in patients with hypertensive disorders of pregnancy, compounded by increasing body mass index. Intermediary factors in the pathway from hypertension to hypoxaemia were also identified.

Preeclampsia and the anaesthesiologist: current management

PURPOSE OF REVIEW

Preeclampsia remains an important cause of maternal and neonatal morbidity and mortality. Recent interest in angiogenic biomarkers as a prognostic indicator is reviewed, together with analgesic, anaesthetic and critical-care management of the preeclamptic patient.

RECENT FINDINGS

There has been recent interest in the angiogenic biomarkers placental growth factor and soluble fms-like tyrosine kinase-1 in establishing the diagnosis of preeclampsia and guiding its management. Neuraxial blocks are recommended for both labour and operative delivery if not contraindicated by thrombocytopenia or coagulopathy, although a safe lower limit for platelet numbers has not been established. For spinal hypotension phenylephrine is noninferior to ephedrine in preeclamptic parturients and may offer some benefits. When general anaesthesia is required, efforts must be made to blunt the hypertensive response to laryngoscopy and intubation. Transthoracic echocardiography has emerged as useful technique to monitor maternal haemodynamics in preeclampsia.

SUMMARY

Improvements in the diagnosis of preeclampsia may lead to better outcomes for mothers and babies. Peripartum care requires a multidisciplinary team approach with many preeclamptic women receiving neuraxial analgesia or anaesthesia. Women with severe preeclampsia may require critical-care support and this should meet the same standards afforded to other acutely unwell patients.

Thoracic ultrasound evaluation and B-type natriuretic peptide value in elective cesarean section under spinal anesthesia

Background

Pregnancy-induced changes in cardiovascular status make women more susceptible to pulmonary edema. During cesarean section, to counterbalance the effect of hypotension caused by spinal anesthesia, anesthesiologists must choose between two fundamental approaches to maintain the hemodynamic state—intravenous fluids or vasopressors—and this choice will depend upon their particular opinions and experience. We aim to assess for any correlations between thoracic ultrasound A- and B-line artifacts, brain natriuretic peptide (BNP) levels, and the amount of intraoperative fluids administered.

Results

From December 2016 to August 2018, at the University-Hospital of Udine, we enrolled 80 consecutive pregnant women undergoing cesarean section. We observed a statistically significant difference in the volume of fluids administered in the first 24 h (p = 0.035) between the patients presenting B-lines in at least one basal area of their thoracic ultrasound and patients with no evident B-lines (AUC 66.4%; IC 0.49–0.83). Dividing the population on whether their BNP levels were higher or less than 20 pg/mL, no statistically significant difference was revealed with regard to fluids administered in the first 24 h (p = 0.537).

Conclusions

Thoracic ultrasound is a non-invasive and easy-to-use tool for detecting fluid intolerance in pregnant women undergoing cesarean section. BNP levels were slow to rise following the cesarean section and did not show any clear correlation with fluid volumes administered.

Restrictive versus Liberal Fluid Therapy for Post-Cesarean Acute Kidney Injury in Severe Preeclampsia: a Pilot Randomized Clinical Trial

OBJECTIVES

The aim of this study was to determine whether a restrictive compared to a liberal fluid therapy will increase postoperative acute kidney injury (AKI) in patients with severe preeclampsia.

METHODS

A total of 46 patients (mean age, 32 years; standard deviation, 6.8 years) with severe preeclampsia were randomized to liberal (1500 ml of lactated Ringer's, n=23) or restrictive (250 ml of lactated Ringer's, n=23) intravenous fluid regimen during cesarean section. The primary outcome was the development of a postoperative renal dysfunction defined by AKI Network stage ≥1. Serum cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) were evaluated at postoperative days 1 and 2. ClinicalTrials.gov: NCT02214186.

RESULTS

The rate of postoperative AKI was 43.5% in the liberal fluid group and 43.5% in the restrictive fluid group (p=1.0). Intraoperative urine output was higher in the liberal (116 ml/h, IQR 69-191) than in the restrictive fluid group (80 ml/h, IQR 37-110, p<0.05). In both groups, serum cystatin C did not change from postoperative day 1 compared to the preoperative period and significantly decreased on postoperative day 2 compared to postoperative day 1 (p<0.05). In the restrictive fluid group, NGAL levels increased on postoperative day 1 compared to the preoperative period (p<0.05) and decreased on postoperative day 2 compared to postoperative day 1 (p<0.05).

CONCLUSION

Among patients with severe preeclampsia, a restrictive fluid regimen during cesarean section was not associated with increased postoperative AKI.

Abnormal lung ultrasound pattern during labor: A prospective cohort pilot study

PURPOSE

Lung ultrasound (LUS) examination is used to evaluate patients with acute respiratory failure. The physiological LUS pattern during labor in healthy parturients has not been well described. The aim of this study was to evaluate the LUS pattern in a cohort of healthy women during uncomplicated labor.

METHODS

We used the 8-point LUS assessment protocol and investigated lung sliding, A-lines, B-lines, interstitial syndrome, lung consolidation, and pleural effusion according to the International Consensus Document with two additional supradiaphragmatic projections. All patients were screened twice; once during the first stage of labor and again within 2 hours after delivery.

RESULTS

We included 24 patients in this study from February 2014 to August 2015. A total of 480 LUS records were retained for further analysis. Overall, 16 of 24 patients (67%) had at least one positive region (three or more B-lines) during the peridelivery LUS evaluation. Interstitial syndrome was detected in five patients (21%). There were no differences in A-line (P = 0.38) or B-line (P = 0.68) prevalence between LUS examinations before and after delivery.

CONCLUSIONS

Women in uncomplicated labor can present abnormal LUS findings, which may affect the interpretation of LUS results in patients with respiratory deterioration. Further studies should address this topic in larger cohort of patients.

Point-of-Care Ultrasound Abnormalities in Late-Onset Severe Preeclampsia: Prevalence and Association With Serum Albumin and Brain Natriuretic Peptide

BACKGROUND

Pilot studies applying point-of-care ultrasound (POCUS) in preeclampsia indicate the presence of pulmonary interstitial edema, cerebral edema, and cardiac dysfunction. Laboratory markers of oncotic pressure (albumin) and cardiac dysfunction (brain natriuretic peptide [BNP]) may be abnormal, but the clinical application remains unclear. We investigated the prevalence of pulmonary interstitial syndrome (PIS), cardiac dysfunction, and increased optic nerve sheath diameter (ONSD) in late-onset preeclampsia with severe features. The primary aim was to examine the association between PIS or ONSD and maternal serum albumin level. The secondary aims were to explore the association between cardiac dysfunction and PIS, ONSD, BNP, and serum albumin level and between POCUS-derived parameters and a suspicious or pathological cardiotocograph.

METHODS

Ninety-five women were enrolled in this prospective observational cohort study. A POCUS examination of lungs, heart, and ONSD was performed. PIS was defined as a bilateral B-line pattern on lung ultrasound and diastolic dysfunction according to an algorithm of the American Society of Echocardiography. ONSD >5.8 mm was interpreted as compatible with raised intracranial pressure (>20 mm Hg). Serum BNP and albumin levels were also measured.

RESULTS

PIS, diastolic dysfunction, systolic dysfunction, and raised left ventricular end-diastolic pressure (LVEDP) were present in 23 (24%), 31 (33%), 9 (10%), and 20 (25%) women, respectively. ONSD was increased in 27 (28%) women. Concerning the primary outcome, there was no association between albumin level and PIS (P = .4) or ONSD (P = .63). With respect to secondary outcomes, there was no association between albumin level and systolic dysfunction (P = .21) or raised LVEDP (P = .44). PIS was associated with diastolic dysfunction (P = .02) and raised LVEDP (P = .009; negative predictive value, 85%). BNP level was associated with systolic (P < .001) and diastolic dysfunction (P = .003) and LVEDP (P = .007). No association was found between POCUS abnormalities and a suspicious/pathological cardiotocograph (P = .07).

CONCLUSIONS

PIS, diastolic dysfunction, and increased ONSD were common in preeclampsia with severe features. Cardiac ultrasound abnormalities may be more useful than albumin levels in predicting PIS. The absence of PIS may exclude raised LVEDP. The further clinical relevance of PIS and raised ONSD remains to be established. BNP level was associated with cardiac ultrasound abnormalities. Although this study was not designed to directly influence clinical management, the findings suggest that POCUS may serve as a useful adjunct to clinical examination for the obstetric anesthesiologist managing these complex patients.

Epidemiology of obstetric critical illness

Obstetric intensive care unit (ICU) admissions comprise only a small part of severe maternal morbidity. The incidence rate of both remains relatively unclear due to inconsistent definitions across publications, although this has begun to be addressed. There is a relative paucity of information regarding disease-specific survival following obstetric ICU admission, but outcomes are clearly related to the cause of admission and the quality of care. The ratio between maternal near-miss cases (many of whom are admitted to ICUs) and maternal death may provide insight into the preventability of death. Hemorrhage and pre-eclampsia constitute the leading causes of ICU admission and have relatively low mortality rates, perhaps demonstrating the impact of informed care in managing obstetric critical illness. Obstetric sepsis, heart disease and anesthesia complications should be the focus of future research. The incidence of obstetric sepsis has been increasing in the last decade, with mortality rates remaining relatively high. The incidence of obstetric heart disease is increasing and maternal complications have been attributed to fractionated care of mothers within this category. Anesthesia complications remain a predominant cause of maternal death and likely intensive care admission. Data are lacking regarding the relative proportion of cases per disease that remain treated outside the ICU; and the outcomes of various management strategies. The only study of the health status of survivors of obstetric ICU admission revealed that six months after hospital discharge, one in five women still had a poorer health-related quality of life than those of a reference age- and sex-matched cohort.

Pre-eclampsia through the eyes of the obstetrician and anesthesiologist

Due to the high risk of morbidity and mortality from unrecognized and untreated pre-eclampsia, clinicians should have a high index of suspicion to evaluate, treat and monitor patients presenting with signs concerning for pre-eclampsia. Early blood pressure management and seizure prophylaxis during labor are critical for maternal safety. Intrapartum, special anesthetic considerations should be employed to ensure the safety of the parturient and fetus. Patients who have pre-eclampsia should be aware that they are at high risk for the future development of cardiovascular disease.

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.

Optic nerve ultrasound for fluid status assessment in patients with severe preeclampsia

Background There are no data on usefulness of optic nerve sheath diameter (ONSD) as a marker of patient's fluid status in preeclampsia. The objective was to examine potential correlation between ONSD and lung ultrasound estimates of extravascular lung water in severe preeclampsia. Patients and methods Thirty patients with severe preeclampsia were included. Optic and lung ultrasound were performed within 24 hours from delivery. ONSD was measured 3 mm behind the globe. Lung ultrasound Echo Comet Score (ECS) was obtained summing B-lines ("comet tails") in parasternal intercostal spaces bilaterally. Pearson's correlation analysis was used to assess the relationship between ONSD and ECS (p < 0.05 significant). Results Median ONSD was 5.7 mm (range 3.8-7.5 mm). Median ECS value was 19 (range 0-24). Statistically significant correlation was found between ONSD and ECS (r2 = 0.464; p < 0.001). Conclusions Significant correlation between ONSD and ECS suggests optic ultrasound could be used for assessing fluid status and guiding peripartum fluid therapy in patients with severe preeclampsia.

Ocular ultrasonography for diagnosing increased intracranial pressure in patients with severe preeclampsia

BACKGROUND

Ultrasound measurements of optic nerve sheath diameter (ONSD) and optic disc height (ODH) measured outside pregnancy correlate with intracranial hypertension. Data on the usefulness of ocular ultrasonography in preeclampsia are limited.

OBJECTIVE

To determine whether ONSD and ODH are greater in patients with features of severe preeclampsia compared to healthy controls.

METHODS

Consecutively admitted patients with severe preeclampsia (according to the ACOG Task Force on Hypertension in Pregnancy) and healthy term control pregnant women were included in this prospective observational study. Optic nerve sheath diameter measured 3 mm behind the globe and ODH were assessed using ocular ultrasonography. Patients with severe preeclampsia were compared to controls before delivery, and at one and four days post-delivery.

RESULTS

We included 30 patients with severe preeclampsia and 30 controls. Optic nerve sheath diameter was significantly higher in patients with severe preeclampsia compared to controls before delivery, and one day and four days post-delivery (P <0.001). Optic disc height was significantly greater in patients with severe preeclampsia compared to controls before delivery (P <0.001), and one day (P <0.001) but not four days, post-delivery (P=0.66). Before delivery, 43% of patients with severe preeclampsia had an ONSD >5.8 mm and 77% an ODH ≥1 mm: compatible with intracranial hypertension. None of the control patients had an ONSD of >5.8 mm or an optic disc height of ≥1 mm before or after delivery.

CONCLUSIONS

Severe preeclampsia was associated with a significantly higher ONSD and increased ODH, which could be ultrasonographic evidence of papilledema.

Thoracic fluid content: a novel parameter for detection of pulmonary edema in parturients with preeclampsia

Acute pulmonary oedema is a serious complication of preeclampsia. Early detection of pulmonary edema in preeclampsia would improve fluid management and would also allow earlier detection of severe cases. The aim of this work is to evaluate the ability of thoracic fluid content measured by electrical cardiometry for early detection of pulmonary edema in parturients with preeclampsia. A prospective observational study included a cohort of preeclamptic parturients. On admission, lung ultrasound score was calculated, and thoracic fluid content was recorded using electrical cardiometry ICON device. Area under receiver operating characteristic (AUROC) curve was calculated for lung ultrasound score, thoracic fluid content for detection of pulmonary edema. Spearman correlation coefficient was calculated for correlation between lung ultrasound score and thoracic fluid content. Sixty patients were included in the study; of them, 6 patients (10%) required diuretics for pulmonary edema. Patients with pulmonary edema had higher lung ultrasound score and thoracic fluid content compared to other patients. Good correlation was reported between Lung ultrasound score and thoracic fluid content (r = 0.82). Thoracic fluid content and lung ultrasound score showed excellent diagnostic properties for pulmonary edema {AUROC: 0.941 (0.849-0.986), best cut-off value: 40 k ohm^-1}, and {AUROC: 0.961 (0.887-0.994), best cut-off value of 15.7}. In parturients with preeclampsia, both lung ultrasound score and thoracic fluid content showed excellent properties for detection pulmonary edema. The high negative predictive value of both tests makes them useful screening tests to rule out pulmonary edema. The excellent correlation between both measures suggests that electrical cardiometry could be a promising surrogate to ultrasound for assessment of extravascular lung water.

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.

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.

[Maternal deaths due to hypertensive disorders. Results from the French confidential enquiry into maternal deaths, 2010-2012]

Between 2010 and 2012, the rate of maternal death caused by hypertensive disorders (0,5/100,000 living birth) was reduced by 50% compared to the 2007-2009 period. Hypertensive disorders were responsible from 5% of maternal deaths and from 10% of direct maternal mortality. Eleven deaths happened during the postpartum period but 9 hypertensive complications began before delivery. Seventy percent of these deaths seem to be avoidable. The main causes of suboptimal management were: unappropriated or insufficient obstetrical and anesthetic treatments, undiagnosed HELLP syndrome and subcapsular liver hematoma, delayed treatment. The analysis of these maternal deaths gave the opportunity to stress some major lessons to optimize medical management in case of hypertensive diseases during pregnancy: abdominal symptoms during third trimester of pregnancy lead to search hypertensive disorders; HELLP syndrome with severe anemia indicate to carry out abdominal ultrasound.

Can point-of-care ultrasound predict spinal hypotension during caesarean section? A prospective observational study

Spinal anaesthesia for elective caesarean section is associated with maternal hypotension, secondary to alteration of sympathetic tone and hypovolemia, in up to 70% of cases. Measurement of the subaortic variation in the velocity time integral (VTI) after passive leg raising allows prediction of fluid responsiveness. Our objective, in this prospective single-centre observational study, was to assess the ability of change in VTI after 45° passive leg raising to predict hypotension after spinal anaesthesia. Ultrasound measurements were performed just before elective caesarean section. Anaesthesia, intravenous coloading and prophylactic vasopressor treatment were standardised according to current guidelines. We studied 40 women. Hypotension occurred in 17 (45%) women. The area (95%CI) under the receiver operating characteristics (ROC) curve for the prediction of spinal hypotension was 0.8 (0.6-0.9; p = 0.0001). Seventeen women had a change in VTI with leg elevation ≤ 8%, which was predictive for not developing hypotension, and 11 had a change ≥ 21%, predictive for hypotension. The grey zone between 8% and 21%, with inconclusive values, included 12 women. We suggest that cardiac ultrasound provides characterisation of the risk of hypotension following spinal anaesthesia at elective caesarean section, and therefore may allow individualised strategies for prevention and management.

Detecting Pulmonary Edema in Obstetric Patients Through Point-of-Care Lung Ultrasonography

BACKGROUND

Point-of-care lung ultrasonography is used in critical care settings for evaluating respiratory symptoms. Lung ultrasonography is sensitive and specific for the diagnosis of pulmonary edema in nonpregnant patients but is not well-studied in pregnancy.

TECHNIQUE

Lung ultrasonography was performed using a portable ultrasound machine with a 2- to 5-MHz curvilinear probe that is available on many labor and delivery units.

EXPERIENCE

Lung ultrasonography guided management decisions in a case of shortness of breath after induction of labor for preeclampsia and a case of hemolysis, elevated liver enzymes, and low platelet count syndrome complicated by pulmonary edema. Findings expedited diagnosis and treatment in both cases.

CONCLUSION

Lung ultrasonography has potential to be used in obstetrics for detecting pulmonary edema in preeclampsia. It is a well-established tool in critical care settings and use in obstetric patients should be studied given the availability of ultrasonography on labor and delivery and the importance of timely care for critically ill pregnant patients. It is a safe modality to evaluate pregnant women with respiratory symptoms and the necessary skills can be easily acquired by obstetric practitioners familiar with obstetric ultrasonography. Training of obstetric practitioners in this application of ultrasonography is needed.