Amniotic fluid embolism: update and review

Amniotic Fluid Embolism After Cervical Ripening

Amniotic fluid embolism (AFE) is a rare condition that can have catastrophic maternal and infant consequences. It can lead to rapid multisystem failure and is responsible for a significant portion of maternal deaths. The diagnosis is frequently made late in the pathological process, and the treatment is mainly supportive and infant delivery. It cannot be prevented. Whether cervical ripening and labor induction are risk factors is controversial. A 31-year-old woman who was undergoing cervical ripening and induction of labor at 38 weeks gestation for medication-controlled gestational diabetes (A2GDM) was admitted for delivery. She received five doses of 25 µg vaginal misoprostol serially and, ultimately, a Foley catheter cervical balloon. After approximately 24 hours, she had the sudden onset of unexpected persistent fetal bradycardia. Her cervix was 4 cm at the time of the fetal distress. When she arrived in the operating room, she was hypoxic and difficult to awaken. An emergency cesarean delivery was performed under general endotracheal anesthesia. Immediately after the delivery of a profoundly depressed and acidotic infant with an umbilical cord pH of 6.84, she became hypotensive, requiring vasopressors. After diffuse intravascular coagulation was diagnosed, treatment for AFE was implemented. AFE has a high mortality rate, and the length of time needed to identify the condition and the availability of specialty resources are two elements that can affect the outcome. Newer alternative treatments, such as the supportive "A-OK" (atropine, ondansetron, and ketorolac administration) protocol for AFE, are discussed. Ultimately, both mother and baby survived and, at the six-month check, are doing well with no sequelae.

Disentangling the phenotypic patterns of hypertension and chronic hypotension

OBJECTIVE

2017 blood pressure (BP) categories focus on cardiac risk. We hypothesize that studying the balance between mechanisms that increase or decrease BP across the medical phenome will lead to new insights. We devised a classifier that uses BP measures to assign individuals to mutually exclusive categories centered in the upper (Htn), lower (Hotn) and middle (Naf) zones of the BP spectrum; and examined the epidemiologic and phenotypic patterns of these BP-categories.

METHODS

We classified a cohort of 832,560 deidentified electronic health records by BP-category; compared the frequency of BP-categories and four subtypes of Htn and Hotn by sex and age-decade; visualized the distributions of systolic, diastolic, mean arterial and pulse pressures stratified by BP-category; and ran Phenome-wide Association Studies (PheWAS) for Htn and Hotn. We paired knowledgebases for hypertension and hypotension and computed aggregate knowledgebase status (KB-status) indicating known associations. We assessed alignment of PheWAS results with KB-status for phecodes in the knowledgebase, and paired PheWAS correlations with KB-status to surface phenotypic patterns.

RESULTS

BP-categories represent distinct distributions within the multimodal distributions of systolic and diastolic pressure. They are centered in the upper, lower, and middle zones of mean arterial pressure and provide a different signal than pulse pressure. For phecodes in the knowledgebase, 85% of positive correlations align with KB-status. Phenotypic patterns for Htn and Hotn overlap for several phecodes and are separate for others. Our analysis suggests five candidates for hypothesis testing research, two where the prevalence of the association with Htn or Hotn may be under appreciated, three where mechanisms that increase and decrease blood pressure may be affecting one another's expression.

CONCLUSION

PairedPheWAS methods may open a phenome-wide path to disentangling hypertension and chronic hypotension. Our classifier provides a starting point for assigning individuals to BP-categories representing the upper, lower, and middle zones of the BP spectrum. 4.7 % of individuals matching 2017 BP categories for normal, elevated BP or isolated hypertension, have diastolic pressure < 60. Research is needed to fine-tune the classifier, provide external validation, evaluate the clinical significance of diastolic pressure < 60, and test the candidate hypotheses.

Amniotic Fluid Embolism in a Patient Presenting for Induction of Labor for Cholestasis of Pregnancy

Amniotic fluid embolism (AFE) is a rare but potentially catastrophic complication during pregnancy. The most common presenting symptoms of AFE are cardiac arrest, hemodynamic instability, and profound hemorrhage. Here, we present a case of a 28-year-old female with a past medical history of anemia, gestational diabetes, hypothyroidism, anxiety, and depression, presenting for induction of labor for cholestasis of pregnancy. The labor course was complicated by sudden cardiac arrest and resuscitation, followed by an emergent bedside peri-cardiac arrest cesarean section. Subsequently, the patient developed coagulopathy, uterine atony, and bleeding from the vagina and cervix. The AFE protocol was initiated, and the care team proceeded with a hysterectomy. Supportive treatment correcting for metabolic acid-base disturbances and coagulopathies was maintained. The patient was stabilized for air transport to a higher level of care.

A Case of Consumptive Coagulopathy Before Cardiopulmonary Failure in Amniotic Fluid Embolism and Review of Literature: A Perspective of the Latent Onset and Progression of Coagulopathy

Amniotic fluid embolism (AFE) induces cardiopulmonary insufficiency with consumptive coagulopathy. Previous studies reported that refractory coagulopathy has already advanced at the onset of maternal cardiovascular and/or respiratory symptoms. However, when the consumption of coagulation factors starts during the clinical course, AFE remains to be elucidated. We report an intrapartum AFE case of consumptive coagulopathy before dyspnea with hypotension developing during urgent cesarean delivery that was revealed by non-reassuring fetal heart rate tracing. The patient, a 42-year-old multiparous parturient, underwent induced labor after a premature rupture of membranes in week 39 of pregnancy. Coagulation screening was initially within the normal range. Fetal heart rate monitoring demonstrated bradycardia coincided with uterine tachysystole after three hours, which required urgent cesarean section with preoperative blood screening. The hemoglobin level was maintained at 129 g/L; however, the fibrinogen value reduced to 1.79 g/L with D-dimer elevation over 60 µg/mL. Ninety minutes later, she developed dyspnea with hypotension at suturing hysterotomy. At the end of surgery, her fibrinogen further decreased to below 0.3 g/L with prolonged prothrombin time. After vigorous intensive care, she was discharged without sequelae. Consumptive coagulopathy may initiate and progress before apparent cardiopulmonary symptoms in some AFE cases. Non-reassuring fetal heart rate tracing concomitant with abrupt uterine tachysystole and/or hypertonus may be an earlier time point for the detection and intervention of AFE-related coagulopathy.

Medical Emergencies in the Pregnant Patient

This review article provides a comprehensive overview of common medical emergencies that can occur in pregnant patients. We summarize the key diagnostic and management steps for each emergency to assist health care professionals in identifying and treating these potentially life-threatening conditions. The medical emergencies discussed in this article include postpartum hemorrhage; hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome; acute fatty liver of pregnancy; amniotic fluid embolism; pulmonary embolism; acute respiratory distress syndrome; and shock. Each condition is described in detail, with a focus on the clinical presentation, diagnostic workup, and treatment options. The information presented in this review article is based on current best practices and guidelines from leading medical organizations. We hope this article will serve as a valuable resource for health care professionals who care for pregnant patients and help improve outcomes for these patients in emergency situations.

Nontrombotic Pulmonary Embolism: Different Etiology, Same Significant Consequences

Nontrombotic pulmonary embolism represents the embolization of different types of materials (cells, organisms, gas, foreign material) into pulmonary circulation. The disease is uncommon, and clinical presentation together with laboratory findings are nonspecific. Its pathology is usually misdiagnosed based on imaging findings as pulmonary thromboembolism, but the correct diagnosis is essential because different therapeutic approaches are required. In this context, knowledge of the risk factors associated with nontrombotic pulmonary embolism and specific clinical symptoms is fundamental. Our objective was to discuss the specific features of the most common etiologies of nontrombotic pulmonary embolism, gas, fat, amniotic fluid, sepsis and tumors, to provide assistance for a rapid and correct diagnosis. Because the most common etiologies are iatrogenic, knowledge of the risk factors could be an important tool for prevention or rapid treatment if the disease develops during different procedures. The diagnosis of nontrombotic pulmonary embolisms represent a laborious challenge, and endeavors should be made to prevent development and increase awareness of this disease.

Patient Blood Management programs for post-partum hemorrhage

Patient blood management (PBM) strategies aim to maintain hemoglobin concentration, optimize hemostasis, and minimize blood loss to improve patient outcomes. Because postpartum hemorrhage (PPH) is a leading cause of maternal mortality and blood product utilization, PBM principles can be applied in its therapeutic approach. First, pre-operative identification of risk factors for PPH and identification of peri-delivery anemia should be conducted. Iron supplementation should be used to optimize hemoglobin concentration before delivery; it can also be used to treat anemia in the postpartum period after severe PPH. Both acute normovolemic hemodilution and intraoperative cell salvage can be effective techniques to reduce allogeneic blood transfusion during or after surgical procedures. Furthermore, these strategies appear to be safe when used in the pregnant population.

Cell-Free Amniotic Fluid and Regenerative Medicine: Current Applications and Future Opportunities

Amniotic fluid (AF) provides critical biological and physical support for the developing fetus. While AF is an excellent source of progenitor cells with regenerative properties, recent investigations indicate that cell-free AF (cfAF), which consists of its soluble components and extracellular vesicles, can also stimulate regenerative and reparative activities. This review summarizes published fundamental, translational, and clinical investigations into the biological activity and potential use of cfAF as a therapeutic agent. Recurring themes emerge from these studies, which indicate that cfAF can confer immunomodulatory, anti-inflammatory, and pro-growth characteristics to the target cells/tissue with which they come into contact. Another common observation is that cfAF seems to promote a return of cells/tissue to a homeostatic resting state when applied to a model of cell stress or disease. The precise mechanisms through which these effects are mediated have not been entirely defined, but it is clear that cfAF can safely and effectively treat cutaneous wounds and perhaps orthopedic degenerative conditions. Additional applications are currently being investigated, but require further study to dissect the fundamental mechanisms through which its regenerative effects are mediated. By doing so, rational design can be used to fully unlock its potential in the biotechnology lab and in the clinic.

Pulmonary Embolism and Amniotic Fluid Embolism

Venous thromboembolism (VTE) as well as other embolic events including amniotic fluid embolism (AFE) remain a leading cause of maternal death in the United States and worldwide. The pregnant patient is at a higher risk of developing VTE including pulmonary embolism. In contrast, AFE is a rare, but catastrophic event that remains incompletely understood. Here the authors review the cause of VTE in pregnancy and look at contemporary and evidence-based practices for the evaluation, diagnosis, and management in pregnancy. Then the cause and diagnostic difficulty of AFE as well as what is known regarding the pathogenesis are reviewed.

A description of the coagulopathy characteristics in amniotic fluid embolism: a case report

Amniotic fluid embolism is frequently associated with coagulopathy. However, the exact nature and evolution of the bleeding disorder is incompletely understood. We report a case of clinically diagnosed amniotic fluid embolism associated with major haemorrhage and coagulopathy. We measured sequential levels of all individual clotting factors, thrombin generation, fibrinogen, and D-dimer levels over the course of the event, beginning shortly after the patient's initial collapse and during the subsequent resuscitation, to identify the specific abnormalities of coagulation from stored blood samples. A better understanding of amniotic fluid embolism and the associated coagulopathy is an important area of research to inform targeted treatment of the coagulopathy and improve outcomes for patients.

Disseminated intravascular coagulation and its immune mechanisms

Disseminated intravascular coagulation (DIC) is a syndrome triggered by infectious and noninfectious pathologies characterized by excessive generation of thrombin within the vasculature and widespread proteolytic conversion of fibrinogen. Despite diverse clinical manifestations ranging from thrombo-occlusive damage to bleeding diathesis, DIC etiology commonly involves excessive activation of blood coagulation and overlapping dysregulation of anticoagulants and fibrinolysis. Initiation of blood coagulation follows intravascular expression of tissue factor or activation of the contact pathway in response to pathogen-associated or host-derived, damage-associated molecular patterns. The process is further amplified through inflammatory and immunothrombotic mechanisms. Consumption of anticoagulants and disruption of endothelial homeostasis lower the regulatory control and disseminate microvascular thrombosis. Clinical DIC development in patients is associated with worsening morbidities and increased mortality, regardless of the underlying pathology; therefore, timely recognition of DIC is critical for reducing the pathologic burden. Due to the diversity of triggers and pathogenic mechanisms leading to DIC, diagnosis is based on algorithms that quantify hemostatic imbalance, thrombocytopenia, and fibrinogen conversion. Because current diagnosis primarily assesses overt consumptive coagulopathies, there is a critical need for better recognition of nonovert DIC and/or pre-DIC states. Therapeutic strategies for patients with DIC involve resolution of the eliciting triggers and supportive care for the hemostatic imbalance. Despite medical care, mortality in patients with DIC remains high, and new strategies, tailored to the underlying pathologic mechanisms, are needed.

Impact of Intraoperative Salvaged Blood Autotransfusion During Obstetric Hemorrhage on the Coagulation Function: A Retrospective Cohort Analysis

Objective

This study aimed to explore the effect of intraoperative blood salvage (autotransfusion) on coagulation function in the rescue of an obstetric hemorrhage.

Methods

A total of 65 pregnant women who were diagnosed with placenta previa in our Hospital and gave birth in the hospital were enrolled in the study. All the patients underwent thromboelastography, routine blood tests, and blood coagulation series + D-dimer before and within 30 min of the autologous blood transfusion. The differences in various indicators were evaluated.

Results

(1) After the autotransfusion, the hemoglobin and neutrophil counts were significantly higher than beforehand, and the platelet count was significantly reduced; the differences were statistically significant (p < .05). (2) There were no significant differences in prothrombin time (PT), fibrinogen, and D-dimer levels before and after the autotransfusion (p > .05). The activated partial thromboplastin time after autotransfusion was shorter than that beforehand, and the difference was statistically significant (p < .05). (3) There were no significant differences in the R value, K value, α value, and MA value of the thromboelastogram before and after the autotransfusion (p > .05).

Conclusion

After the recovery autotransfusion, the hemoglobin of patients with a massive obstetric hemorrhage increased significantly, while the platelet count decreased, but the coagulation function and thromboelastogram did not change significantly, indicating the autotransfusion did not affect the coagulation function of the obstetric hemorrhage rescue. Thus, it would appear that intraoperative blood salvage can be safely used in the clinical rescue of massive hemorrhaging during cesarean section.

Bone cement implantation syndrome induced by antibiotic-loaded bone cement covering the infected bone surface: A case report

INTRODUCTION AND IMPORTANCE

Bone cement implantation syndrome (BCIS) typically occurs during bone cementation and prosthesis insertion. Almost all of the models used to explain BCIS are based on studies related to hip arthroplasty. BCIS induced by bone cement implantation in superficial wounds has not been reported.

CASE PRESENTATION

We report the case of a 37-year-old man with chronic osteomyelitis of the left tibia (Cierny - Mader type II), who developed BCIS after covering the infected bone surface with antibiotic-loaded bone cement. BCIS presented as acute massive pulmonary exudation and hypoxemia. Early application of awake prone positioning effectively improved oxygenation and lung injury, and prevented the need for a more advanced means of respiratory support. The patient was discharged without any clinical complications on postoperative day 15.

CLINICAL DISCUSSION

We assessed the cause of acute respiratory events in this patient using Naranjo Adverse Drug Reaction Probability Scale, and BCIS was finally considered. Despite the lack of "driving force" (e.g., increased intramedullary pressure), the bone cement monomer may be absorbed into circulation through the wound surface due to its penetrability. Subsequent immune-mediated amplification resulted in pulmonary exudation and hypoxemia. As a pathophysiologically change-oriented strategy, effective drainage after awake prone positioning significantly improved clinical outcomes.

CONCLUSION

Bone cement monomer absorbed through the wound should be of concern, and pathophysiological change-oriented management should be emphasized in BCIS.

A ten-year retrospective review of maternal cardiac arrest: Incidence, characteristics, causes, and outcomes in a tertiary-care hospital in a developing country

OBJECTIVE

Maternal cardiac arrest is rare. We retrospectively reviewed and reported (1) the incidence of maternal cardiac arrests during admissions for delivery; (2) the characteristics and causes of cardiac arrest; and (3) the mortality rate and outcomes in a referral, single-university, teaching hospital in Thailand.

MATERIALS AND METHODS

Data on 23 cardiac arrests during admissions for delivery in the decade January 2006-December 2015 were retrospectively chart-reviewed. Patients with gestational ages under 24 weeks or cardiac arrests and death occurring before hospital arrival were excluded. The clinical characteristics of the arrests and outcomes were collected.

RESULTS

Of 89,368 deliveries during the decade, 23 women suffered cardiac arrest (incidence, 1:3885), with 3 of those arrests occurring before delivery (incidence, 1:29,789). One patient underwent a perimortem cesarean delivery in the operating theatre. The most common reasons for the arrests were hypertension during pregnancy and cardiovascular causes (30.4% and 21.7%, respectively). Amniotic fluid embolisms were suspected for 2 patients (8.7%) with unidentified causes. The incidence of maternal deaths in peripartum cardiac arrests was 20/23, representing 86.9% (95% CI, 67.9-95.5) or 1:4468 of deliveries. Three patients suffering cardiac arrests after delivery survived to discharge.

CONCLUSIONS

We found a high maternal mortality rate following cardiac arrests during hospitalization for delivery. To decrease the incidence of arrests during the peripartum period and diminish the maternal mortality rate, identification of the causes and precipitating factors is vital. High-risk pregnant women require multidisciplinary care to improve the survival-to-discharge rate.

Postpartum Respiratory Depression

Postpartum respiratory depression is a complex, multifactorial issue that encompasses a patient's baseline preexisting conditions, certain pregnancy-specific conditions or complications, as well as the iatrogenic element of various medications given in the peripartum period. In this review, we discuss many of these factors including obesity, sleep-disordered breathing, chronic lung disease, neuromuscular disorders, opioids, preeclampsia, peripartum cardiomyopathy, postpartum hemorrhage, amniotic fluid embolism, sepsis, acute respiratory distress syndrome (ARDS), and medications such as analgesics, sedatives, anesthetics, and magnesium. Current recommendations for screening, treatment, and prevention are also discussed.

Cardiac Arrest during Cesarean Section - A Case Report and Review of the Differential Diagnosis

AIM

According to the World Health Organization, approximately 810 pregnant women die every day as a consequence of peripartum complications. A large proportion of deaths happen in developing countries. Peripartum cardiac arrest is a rare event that must be treated immediately. It is important to consider the differential diagnoses in order to save lives.

METHODS

In this review, we discuss a differential diagnosis of cardiac arrest according to the BEAU-CHOPS scheme of the American Heart Association in the relation to the case report of our 40-year-old G5/P3 patient who went into cardiac arrest during cesarean delivery.

RESULTS

Typical differentials for cardiac arrest during labor are bleeding, embolism, anesthetic complications, cardiovascular diseases, eclampsia, and sepsis. All of them were considered and ruled out in this patient. In the end, we suspect that physiological cardio-inhibitory reflexes triggered by sudden profound hypovolemia after placental separation along with the patient's risk factors, especially obesity and maternal age, and the administration of spinal anesthesia all potentially contributed to the cardiac arrest.

CONCLUSIONS

This review highlights that the cardiac arrest during labor can be triggered by the multifactorial etiology, but firstly the typical differential diagnosis needs to be excluded.

A Detailed Review of Critical Care Considerations for the Pregnant Cardiac Patient

Maternal cardiovascular disease is a leading cause of maternal death worldwide and recently, maternal mortality has increased secondary to cardiovascular causes. Maternal admissions to critical care encompass 1%-2% of all critical care admissions, and although not common, the management of the critically ill pregnant patient is complex. Caring for the critically ill pregnant cardiac patient requires integration of pregnancy-associated physiologic changes, understanding pathophysiologic disease states unique to pregnancy, and a multidisciplinary approach to timing around delivery as well as antenatal and postpartum care. Herein we describe cardiorespiratory changes that occur during pregnancy and the differential diagnosis for cardiorespiratory failure in pregnancy. Cardiorespiratory diseases that are either associated or exacerbated by pregnancy are highlighted with emphasis on perturbations secondary to pregnancy and appropriate management strategies. Finally, we describe general management of the pregnant cardiac patient admitted to critical care.

Extracorporeal Membrane Oxygenation Therapy After Amniotic Fluid Embolism With Undetectable ROTEM FIBTEM Activity: A Case Report

Amniotic fluid embolism (AFE) is a rare but devastating condition with mortality rates as high as 60%-80%., We report a case of AFE complicating the labor of a parturient with no reported risk factors. She received general anesthesia for emergent cesarean delivery (CD), after which she developed a pulseless electrical activity (PEA) event requiring resuscitation, disseminated intravascular coagulation, and postpartum hemorrhage with undetectable fibrinogen activity by ROTEM FIBTEM assay. Extracorporeal membrane oxygenation (ECMO) therapy was successfully initiated, and she was discharged home without neurologic sequelae. ECMO therapy can be considered for the treatment of AFE even in the absence of fibrinogen activity.

The role of echocardiography in amniotic fluid embolism: a case series and review of the literature

PURPOSE

Amniotic fluid embolism (AFE) is a rare, but often fatal condition characterized by sudden hemodynamic instability and coagulopathy occurring during labour or in the early postpartum period. As the mechanisms leading to shock and the cardiovascular effects of AFE are incompletely understood, the purpose of this case series is to describe how AFE presents on echocardiography and review limited reports in the literature.

CLINICAL FEATURES

We describe three cases of AFE at the Jewish General Hospital, a tertiary care centre in Montreal, Canada. All cases met the Clark diagnostic criteria, which comprise 1) sudden cardiorespiratory arrest or both hypotension and respiratory compromise, 2) disseminated intravascular coagulation, 3) clinical onset during labour or within 30 min of delivery of the placenta, and 4) absence of fever. Two patients had a cardiac arrest and the third developed significant hypotension and hypoxia. In all patients, point-of-care echocardiography at the time of shock revealed signs of right ventricular failure including a D-shaped septum, acute pulmonary hypertension, and right ventricular systolic dysfunction.

CONCLUSION

This case series and literature review of AFE emphasizes the importance of echocardiography in elucidating the etiology of maternal shock. The presence of right ventricular failure may be considered an important criterion to diagnose AFE.

Venoarterial extracorporeal membrane oxygenation as an early treatment for amniotic fluid embolism with cardiac arrest: A case report

Amniotic fluid embolism (AFE) is a rare but fatal obstetric complication, characterized by sudden cardiovascular collapse, respiratory failure, and disseminated intravascular coagulation. Maternal mortality associated with AFE is high, making early recognition and prompt treatment important. In AFE with cardiac arrest, survival following acute cardiopulmonary dysfunction is crucial. In recent years, venoarterial extracorporeal membrane oxygenation (VA-ECMO) has attracted attention as an aggressive treatment for AFE with cardiac arrest. A 40-year-old woman experienced sudden cardiac arrest due to AFE during cesarean section. Cardiopulmonary resuscitation and VA-ECMO (also called percutaneous cardiopulmonary support) were initiated early. Finally, she recovered without any complications. VA-ECMO can provide temporary respiratory and hemodynamic support until cardiopulmonary function improves after a few days in intensive care. VA-ECMO should be considered as an early treatment for AFE with cardiac arrest.

Role of Critical Care Units in the management of obstetric patients (Review)

Pregnancy is considered a natural process for the majority of women. However, a limited proportion of pregnancies and deliveries can present with a broad variety of complications that may require admission to a Critical Care Unit (CCU). In the present review, the indications of admission of obstetrical and postpartum patients to CCUs were critically evaluated with a particular focus on the management of their complications. The management of critically ill obstetric patients remains challenging due to the physiological changes that occur during pregnancy, pregnancy-related diseases and the need to carefully consider the well-being of the fetus before any intervention can be recommended/performed. Indications for admission to CCUs include both obstetric and non-obstetric conditions that may require continuous monitoring and further interventions. Hypertensive disorders of pregnancy and mass hemorrhage are amongst the most common causes of admission to CCUs in pregnant and postpartum women. The establishment of a diagnostic and care algorithm based on the contribution of a multidisciplinary team is of critical importance to aid in the determination of which patients will require intensive care, and to assist in deciding what type of critical care each critically ill patients receives.

[Special pathologies of pregnant patients in intensive care medicine]

Da die Inzidenz intensivtherapiepflichtiger Erkrankungen in Schwangerschaft oder Puerperium sehr niedrig ist, werden Intensivmediziner bei der Behandlung dieser Patientinnen vor eine Vielzahl von ungewohnten Herausforderungen gestellt. Die physiologischen und pathophysiologischen Veränderungen während einer Schwangerschaft bedingen einige Besonderheiten bezüglich der intensivmedizinischen Behandlung schwangerer oder kürzlich entbundener Patientinnen. Nachdem im ersten Beitrag dieser CME-Reihe die wichtigsten Prinzipien und aktuellen Empfehlungen zur Versorgung intensivtherapiebedürftiger schwangerer oder frisch entbundener Patientinnen behandelt wurden, fokussiert der zweite Beitrag auf Diagnostik und Therapie spezieller, ausgewählter Krankheitsbilder.

Contribution of blood detection of insulin-like growth factor binding protein-1 for the diagnosis of amniotic-fluid embolism: a retrospective multicentre cohort study

OBJECTIVE

To assess the contribution of maternal blood detection of IGFBP-1 for the diagnosis of amniotic-fluid embolism in clinical daily practice.

DESIGN

A retrospective multicentre cohort study.

SETTING

Three tertiary care obstetric units in France.

SAMPLE

Data of 86 women for whom amniotic-fluid embolism had been suspected and maternal serum detection of IGFBP-1 had been performed between 2011 and 2019 were analysed.

METHODS

The criteria defined by the United Kingdom Obstetric Surveillance System (UKOSS) were used for the retrospective diagnosis of amniotic-fluid embolism. The more structured definition proposed by the Society for Maternal-Fetal Medicine and the Amniotic Fluid Embolism Foundation (SMFM) was also used as secondary endpoint.

MAIN OUTCOME MEASURES

Agreements between biological and clinical assessments were tested. The performance of blood detection of IGFBP-1 for the diagnosis of amniotic-fluid embolism according to the UKOSS criteria, and to the SMFM definition, was also assessed.

RESULTS

There was only slight agreement between clinical and laboratory diagnosis of amniotic-fluid embolism (Cohen's Kappa coefficient: 0.04). Blood detection of IGFBP-1 had a sensitivity of 16%, a specificity of 88%, a positive and a negative likelihood ratio of 1.3 and 0.95, respectively, and a positive and a negative predictive value of 58 and 50%, respectively, for the diagnosis of amniotic-fluid embolism based on the UKOSS criteria. The use of the more structured SMFM definition of amniotic-fluid embolism did not substantially change the results.

CONCLUSION

These results question the usefulness of blood detection of IGFBP-1 for the early diagnosis of amniotic-fluid embolism in daily clinical practice.

TWEETABLE ABSTRACT

This retrospective multicentre study questions the contribution of IGFBP-1 detection for the diagnosis of AFE.

Summary of clinically diagnosed amniotic fluid embolism cases in Korea and disagreement with 4 criteria proposed for research purpose

OBJECTIVE

This study aimed 1) to investigate the clinical characteristics of amniotic fluid embolism (AFE) cases clinically diagnosed by maternal fetal medicine (MFM) specialists in Korea, 2) to check the disagreement with 4 recently proposed criteria by the Society for Maternal-Fetal Medicine (SMFM) for research purpose, and 3) to compare maternal outcomes between cases satisfying all 4 criteria and cases with at least 1 missing criterion.

METHODS

This study included 12 patients clinically diagnosed with AFE from 7 referral hospitals in Korea. We collected information, including maternal age, symptoms of AFE, the amount of transfusion, and maternal mortality.

RESULTS

The median maternal age was 33 years (range, 28-40 years). Regarding symptoms, cardiovascular arrest, hypotension, respiratory compromise, clinical coagulopathy, and neurologic signs were observed in 41.7%, 83.3%, 83.3%, 100%, and 66.7% of the cases, respectively. Among the 12 cases, 5 women died and 2 suffered severe neurologic disability, showing an intact survival rate of 41.7%. Disagreement with all 4 criteria proposed by the SMFM was found in 66.7% of the cases, due to the lack of criteria for disseminated intravascular coagulation or strict onset time (<30 minutes after delivery). There was no difference in maternal mortality and the amount of transfusion between cases satisfying all 4 criteria and cases with at least 1 missing criterion.

CONCLUSION

Two-thirds of clinically confirmed AFE cases did not satisfy all 4 criteria proposed by the SMFM, despite similar rates of maternal mortality with cases satisfying all 4 criteria. Our study suggests that there may be some discrepancy between the clinical diagnosis of AFE and the recent diagnostic criteria proposed by the SMFM for research purpose.

Anesthesia for Obstetric Disasters

Over the past 30 years, maternal mortality has increased in the United States to 18 deaths per 100,000 live births. Obstetric emergencies, including hemorrhage, hypertensive disorders in pregnancy, HELLP syndrome, and amniotic fluid embolism, and anesthesia complications, including high neuraxial blockade, local anesthetic systemic toxicity, and the difficult obstetric airway, contribute to maternal cardiac arrest and maternal and fetal morbidity and mortality. Expeditious intervention by the obstetric anesthesiologist is critical in these emergent scenarios, and knowledge of best practices is essential to improve maternal and fetal outcomes.

Anesthesia for Obstetric Disasters

Over the past 30 years, maternal mortality has increased in the United States to 18 deaths per 100,000 live births. Obstetric emergencies, including hemorrhage, hypertensive disorders in pregnancy, HELLP syndrome, and amniotic fluid embolism, and anesthesia complications, including high neuraxial blockade, local anesthetic systemic toxicity, and the difficult obstetric airway, contribute to maternal cardiac arrest and maternal and fetal morbidity and mortality. Expeditious intervention by the obstetric anesthesiologist is critical in these emergent scenarios, and knowledge of best practices is essential to improve maternal and fetal outcomes.

Extracorporeal Therapies for Amniotic Fluid Embolism

BACKGROUND

Amniotic fluid embolism (AFE) is a catastrophic disease with significant mortality. Because the cardiopulmonary dysfunction associated with AFE is self-limited, the disease could be well suited to the use of extracorporeal therapies.

CASE

A woman progressed into cardiac arrest immediately after an elective cesarean delivery. Owing to severe hypoxemia and hypotension, AFE was suspected and peripheral venoarterial extracorporeal membrane oxygenation was quickly initiated. Subsequent evolution was complicated by intrabdominal bleeding, which required massive transfusion and multiple surgeries. The patient recovered well, with a healthy newborn. We have identified 19 similar cases in the literature and present their outcomes as a series.

CONCLUSION

Extracorporeal therapies can support severely ill women affected by AFE and could be considered even in the presence of disseminated intravascular coagulation and bleeding.

Extracorporeal Membrane Oxygenation During Adult Noncardiac Surgery and Perioperative Emergencies: A Narrative Review

Over the last decade, the use of extracorporeal membrane oxygenation (ECMO) has increased significantly. In some centers, ECMO has been deployed to manage perioperative emergencies and plays a role in facilitating high-risk thoracic, airway, and trauma surgery, which may not be feasible without ECMO support. General anesthesiologists who usually manage these cases may not be familiar with the initiation and management of patients on ECMO. This review discusses the use of ECMO in the operating room for thoracic, airway, and trauma surgery, as well as obstetric and perioperative emergencies.

Amniotic Fluid Embolism Treated with Veno-Arterial Extracorporeal Membrane Oxygenation

Amniotic fluid embolism (AFE) is an extremely rare yet fatal obstetric emergency. AFE presents as sudden cardiovascular collapse after a breach of maternal-fetal membranes and is often complicated by severe coagulopathy. We present a case where an AFE was treated with veno-arterial extracorporeal membrane oxygenation (ECMO) to help overcome the acute cardiopulmonary insult. The use of echocardiography proved to be an invaluable tool to help guide treatment and optimal duration of ECMO in the face of severe coagulopathy.

A case of amniotic fluid embolism successfully treated by multidisciplinary treatment

Background

Amniotic fluid embolism (AFE) is a life-threatening obstetric emergency. Because the maternal mortality associated with AFE is very high, early recognition and prompt treatment are important for improving the prognosis. We report a case of amniotic fluid embolism successfully treated by multidisciplinary treatment.

Case presentation

A 39-year-old woman with fetal congenital heart anomaly and polyhydramnios was scheduled for induction of delivery at 37 weeks of gestation with labor epidural analgesia. Uncontrollable bleeding occurred 30 min after vaginal delivery. Based on the clinical diagnosis of AFE, massive blood transfusion, insertion of an aortic occlusion balloon catheter, and hysterectomy was performed. Total blood loss was 12,000 mL. The diagnosis of AFE was confirmed by pathological examination. She was discharged with no complications.

Conclusion

We report a case of AFE who were rescued by prompt diagnosis and treatment.

Pulmonary amniotic fluid embolism in a rhesus macaque (Macaca mulatta)

A pregnant female rhesus macaque died spontaneously during stage two labor. Gross and histopathologic findings included severe pulmonary edema, with low numbers of blood vessels containing pale basophilic mucinous material (Alcian Blue positive and PTAH negative), consistent with intravascular amniotic fluid-derived mucin resulting in pulmonary amniotic fluid embolism.

Placental Chorionic Cyst Fluid Has Prothrombotic Properties and Differs From Amniotic Fluid

INTRODUCTION

Chorionic cysts of the chorion laeve, fetal chorionic plate, septum, and free membranes have been associated with placental hypoxia, but they have no clear clinical significance. Although immunohistochemistry has identified fibronectin and collagen IV in cyst fluid, the contents have yet to be fully characterized.

METHODS

Placental chorionic cysts (N = 10) were sampled by fluid extraction and hemotoxylin and eosin-stained sections. Amniotic fluid samples (N = 8) were obtained from pregnant women who had cytogenetic evaluation. The content of the cysts was tested for thrombogenicity using thromboelastography. The cyst content was tested by Luminex multiplex and ELISA assays and for known prothrombotic and proinflammatory factors.

RESULTS

We identified cysts, especially those in the chorionic plate, adjacent to intervillous thrombi with apparent cyst rupture. Thromboelastography revealed a significantly shorter R time compared to whole blood control samples. Concentration of creatinine, α-fetoprotein, and surfactant D in the cyst fluid differed significantly from amniotic fluid. Cyst fluids had a significantly higher expression of all prothrombotic and some proinflammatory factors.

DISCUSSION

Our data provide the first evidence that chorionic cyst fluid is prothrombotic and different from amniotic fluid. The association of ruptured cysts with adjacent thrombi and the prothrombotic properties of cyst fluid suggest a causal relationship; however, further studies are needed.

Clinical Presentation and Treatment of Amniotic Fluid Embolism

Obstetric emergencies often require intensive care intervention. Amniotic fluid embolism is a rare, unpredictable, and often catastrophic complication of pregnancy that is suspected in a woman who experiences cardiac arrest after a cesarean section. The condition occurs in approximately 1 in 40 000 births and has an average case-fatality rate of 16%. This complication may result from activation of an inflammatory response to fetal tissue in the maternal circulation. Risk factors may include maternal age over 35 years and conditions in which fluid can exchange between the maternal and fetal circulations. The presentation is abrupt, with profound cardiovascular and respiratory compromise, encephalopathy, fetal distress, and disseminated intravascular coagulopathy. Diagnosis is by exclusion and clinical presentation. Treatment is supportive, with a focus on reversal of hypoxia and hypotension, delivery of the fetus, and correction of coagulopathy. Staff debriefing and psychological support for the woman and family are vital.

Atypical Amniotic Fluid Embolism Managed with a Novel Therapeutic Regimen

Amniotic fluid embolism (AFE) is the second leading cause of maternal mortality in the USA with an incidence of 1 : 15,200 births. The case fatality rate and perinatal mortality associated with AFE are 13–30% and 9–44%, respectively. This rare but devastating complication can be difficult to diagnose as many of the early signs and symptoms are nonspecific. Compounding this diagnostic challenge is a lack of effective treatment regimens which to date are mostly supportive. We present the case of a 26-year-old woman who suffered from suspected AFE and was successfully treated with the novel regimen of Atropine, Ondansetron, and Ketorolac (A-OK). The authors acknowledge that this case does not meet the new criteria proposed, by Clark in 2016, but feel that it is important to share this case report, due to dramatic patient response to the provided supportive therapy presented in this case report. We hope this case report will prompt further research into this novel approach to treating AFE with Atropine, Ondansetron, and Ketorolac.

Anesthetic management of amniotic fluid embolism -- a multi-center, retrospective, cohort study

INTRODUCTION

Amniotic fluid embolism (AFE) is a rare and potentially lethal obstetric complication, commonly occurring during labor, delivery, or immediately postpartum. There is a paucity of data regarding incidence, risk factors, and clinical management. Our primary objective in this study was to evaluate clinical presentation of AFE and delineate anesthesia management of these cases.

METHODS

This 10 years retrospective multi-center cohort study was performed in five tertiary university-affiliated medical centers, between the years 2005 and 2015. All documented cases of AFE identified according to the ICD guidelines were reviewed manually to determine eligibility for AFE according to Clark's criteria. All cases confirming Clark's diagnosis were included in the cohort.

RESULTS

Throughout the study period, 20 cases of AFE were identified, with an incidence of 4.1 per 100,000 births. Average age at presentation was 35 ± 5 years. Seventy percent of cases presented during vaginal delivery, 20% occurred throughout a cesarean delivery, and 10% occurred during a dilation and evacuation procedure. The most common presenting symptom was sudden loss of consciousness in 12 parturients (66.7%), fetal bradycardia in 11 parturients (55%), and shortness of breath in 10 parturients (50%). Perimortem cesarean section was performed in 55% of cases, although only one case was performed in the delivery suite, while all others were performed in the operating room. Echocardiography was performed in 60% of the cases and all were pathological. Furthermore, 20% of cases were connected to an extracorporeal membrane oxygenation machine. There was a 15% mortality rate of 15%. A further 15% suffered major neurological disability, 25% suffered minor neurological morbidity, and 45% survived without severe complications.

CONCLUSION

AFE is associated with significant maternal morbidity. This study highlights the importance of providing advanced training for the delivery suite staff for cases of maternal cardiovascular collapse secondary to AFE and increasing awareness for this rare and devastating obstetric condition.

Surveillance of the safety and efficacy of recombinant human soluble thrombomodulin in patients with obstetrical disseminated intravascular coagulation

BACKGROUND

Recombinant human soluble thrombomodulin (TM-α) has been shown to be useful in the treatment of disseminated intravascular coagulation (DIC) in a heparin-controlled study, and has been available for clinical use in Japan since 2008. However, use of TM-α for obstetrical DIC has not yet been established, so efficacy and safety were analyzed in 117 obstetrical DIC patients identified from post-marketing surveillance.

MATERIALS AND METHODS

From June 2010 to March 2012, the cases of 117 patients with obstetrical DIC treated with TM-α were registered.

RESULTS

In the majority of cases, the underlying disease was DIC-type postpartum hemorrhage (n=43) or placental abruption (n=37). Mean (±standard deviation) obstetrical DIC score was 10.6±4.9. Mean duration of TM-α administration was 2.2±1.7days. The most commonly used concomitant anticoagulants were antithrombin (n=60) and gabexate mesilate (n=37). Concomitantly used blood components products included red blood cell concentrate (n=72), fresh frozen plasma (n=70), and platelet concentrate (n=31). Hemostatic test result profiles revealed significant improvement of fibrinogen/fibrin degradation products, D-dimer, fibrinogen, prothrombin time and activated partial thromboplastin time. Efficacies of TM-α as evaluated by "The efficacy evaluation criteria for DIC in obstetrics" at 24h, 48h and the day after last administration of TM-α were 72.3%, 82.4% and 90.2%, respectively. Total bleeding adverse drug reactions occurred in 6 patients (5.1%).

CONCLUSIONS

This surveillance confirmed the safety and efficacy of TM-α in clinical practice. These findings thus indicated that the efficacy of TM-α is comparable to that of previously investigated obstetrical DIC pharmacotherapies.