Mechanism and cLinicaL characteristics in diagnosis and treatment of amniotic fluid emboLism / 中华围产医学杂志

Amniotic fluid embolism(AFE) is a fatal intrapartum complication. Typical AFE is characterized by respiratory and circulatory failure, followed by disseminated intravascular coagulation(DIC), while atypical AFE, which had a higher survival possibility, presents with unexplained DIC only. Recent findings support an anaphylactoid inflammatory mechanism underlying the pathophysiology of AFE. Milrinone is currently the first choice for AFE due to its several functions, such as reducing pulmonary artery pressure, and improving right ventricular function through lowering heart rate and positive inotropic action. A multidisciplinary team is required in the rescue of AFE and medical staff who are skilled in critical medicine (such as anesthesiologists) often play a pivotal role.

Embolismo de líquido amniótico: mitos y realidades etiopatogénicas de un síndrome potencialmente fatal / Amniotic fluid embolism: etiopathogenic realities and myths of a potentially fatal syndrome

Fundamento: el embolismo de líquido amniótico es un síndrome catastrófico que ocurre durante el trabajo de parto, el parto o inmediatamente. De incidencia variable, es la segunda causa de muerte materna en muchas partes del mundo y que reporta tasas de hasta un 60 % en países desarrollados. En las últimas dos décadas un trabajo de investigación más riguroso ha mejorado enormemente la comprensión de esta condición. Objetivo: exponer los elementos más recientes que intentan explicar la etiología y la fisiopatología del embolismo de líquido amniótico. Método: se realizó una revisión en 32 bibliografías entre revistas y textos clásicos, a través de la biblioteca virtual cubana, Lilacs, PubMed y Medline. Desarrollo: la embolia de líquido amniótico es, desde un punto de vista fisiopatológico, parecida al síndrome de respuesta inflamatoria sistémica, común en condiciones tales como choque séptico, en el que una respuesta anormal del huésped es la principal responsable de las manifestaciones clínicas. La teoría bimodal es la regla: una fase temprana caracterizada por vasoespasmo e hipertensión pulmonar y fallo ventricular derecho; otra tardía donde prima el fallo ventricular izquierdo, el edema pulmonar, el shock y los trastornos de la coagulación. Conclusiones: la base fisiopatológica de toda esta secuencia de alteraciones hemodinámicas parece implicar una secuencia compleja de reacciones resultantes de la activación anormal de sistemas mediadores pro inflamatorios similares a los presentes en el síndrome de respuesta inflamatoria sistémica, que sigue al casi universal paso de antígenos fetales a la circulación materna durante el proceso de parto.

Background: amniotic fluid embolism is a catastrophic syndrome that takes place during the onset of labor or during the labor. This syndrome of variable incidence is the second cause of maternal death in many regions of the world. Rates up to 60 % are reported in developed countries. A more rigid investigation has greatly increased the comprehension of this condition in the last two decades. Objective: to set out the most recent elements that try to explain the etiology and physiopathology of amniotic fluid embolism. Method: a review of 32 bibliographies, including journals and classic texts, was made through the Cuban virtual library, Lilacs, PubMed and Medline. Development: amniotic fluid embolism is, from the physiopathological point of view, similar to the systemic inflammatory response syndrome, and it is common in conditions like septic shock, in which the abnormal response of the host is the main responsible for the clinical manifestations. Bimodal theory is the rule: an early stage characterized by vasospasm and pulmonary hypertension and heart failure; and a late stage where left heart failure, pulmonary edema, shock and coagulation disorders predominate. Conclusions: the physiopathological basis of this sequence of hemodynamic changes seems to entail a complex sequence of reactions that result from the abnormal activation of proinflammatory mediator systems, similar to those present in the systemic inflammatory response syndrome that follows the almost universal flow of fetal antigens to the maternal circulation during labor.

Embolia de líquido amniótico: reporte de cuatro casos en el Hospital Universitario La Paz en Madrid, España, y revisión de la literatura / Amniotic fluid embolism: report of four cases at Hospital Universitario La Paz, in Madrid, Spain, and review of the literature

Introducción: la embolia de líquido amniótico (ELA) es una entidad poco frecuente, considerada como impredecible y no prevenible, que se asocia a una elevada morbimortalidad materna. El diagnóstico temprano es necesario para mejorar el pronóstico fetal. El objetivo de este reporte de casos es revisar el diagnóstico, el tratamiento y los principales puntos de discusión en la literatura respecto a esta patología.Materiales y métodos: presentamos el reporte de cuatro casos de ELA que se presentaron en un periodo de diez años en el Hospital Universitario La Paz de Madrid, España, centro de alta complejidad perteneciente el sistema nacional de salud. Se presenta de manera detallada uno de los casos por ser el más representativo del cuadro en cuanto a características clínicas y secuencia cronológica de aparición de los síntomas. Se realiza una búsqueda en las bases de datos Medline vía PubMed, en español e inglés en los últimos diez años con los términos: embolia de líquido amniótico, paro cardiaco, coagulación intravascular diseminada y mortalidad neonatal. Se buscaron series de casos, estudios de cohortes, casos y controles, y artículos de revisión.Resultados: se encontraron 150 títulos de los cuales se incluyeron 26, de estos 10 correspondieron a series de casos, 5 cohortes y 11 revisiones. El diagnóstico se basa en criterios clínicos; el tratamiento temprano se enfoca a un soporte cardiorrespiratorio y hemodinámico. Conclusión: es necesario un adecuado conocimiento de la ELA para establecer un diagnóstico de sospecha y poder orientar de la forma más adecuada el manejo terapéutico de estas pacientes en el menor tiempo posible.

Introduction: Amniotic fluid embolism (AFE) is an infrequent condition considered unpredictable and unpreventable, and it is associated with high maternal morbidity and mortality. Early diagnosis is critical in order to improve prognosis. The objective of this case report is to review the diagnosis, treatment and main discussion points found in the literature regarding this disease condition. Material and methods: We report 4 cases of AFE presenting over a period of 10 years to the Hospital Universitario La Paz, in Madrid, Spain, a high complexity center of the national health system. One of the cases is reported in detail because it is the most representative of the disease presentation in terms of the clinical characteristics and the time sequence of symptom onset. A search was conducted in English and Spanish in Medline via Pub Med for the last 10 years, using the terms amniotic fluid embolism, cardiac arrest, disseminated intravascular coagulation, neonatal mortality. The search included case series, cohort studies, cases and controls, and review articles. Results: Of a total of 150 titles found, 26 were included: 10 case series, 5 cohort studies and 11 reviews. The diagnosis is based on clinical criteria and early treatment is focused on cardiorespiratory and hemodynamic support. Conclusion: Adequate knowledge of AFE is required in order to suspect the diagnosis and guide therapeutic management in these patients as adequately and promptly as possible.

Embolia por líquido amniótico / Amniotic fluid embolism

A embolia por líquido amniótico (ELA) é uma entidade rara, porém associada a elevados índices de mortalidade para o binômio materno-fetal e também à morbidade devido às sequelas neurológicas de longo prazo. Em relação à mortalidade, ela vem decrescendo nos últimos inquéritos, porém ainda permanece entre as causas mais importantes de morte materna no mundo. A síndrome parece ser mais incidente do que tem sido publicada, porém somente são catalogados casos clinicamente exuberantes. No Brasil, o sub-registro das declarações de óbito dificulta ainda mais o real monitoramento dessa complicação. Algumas revisões já foram escritas sobre o tema e em todas a dúvida quanto à etiopatogenia dessa entidade permanece no centro da discussão. A ELA apresenta, ainda, fisiopatologia complexa que conduz a: hipertensão pulmonar,falência cardíaca e coagulação intravascular disseminada. O diagnóstico é clínico e, sobretudo, de exclusão, não havendo até o momento nenhum método isolado capaz de confirmar a embolia por líquido amniótico. A conduta mediante a suspeita é a instituição precoce e eficaz de medidas de suporte a vida e, como em mais de 60% dos casos o feto está intraútero, sua extração imediata deve ser realizada, se houver maturidadepulmonar para tal. Amplia-se aqui a discussão sobre uma hipótese: a dramaticidade dos casos estaria relacionada não propriamente ao fenômeno embólico, mas sim às alterações humorais provocadas por fatores contaminantes, como a presença de mecônio no conteúdo embolizado.

Amniotic Fluid Embolism (AFE) is rare, but associated with high mortality and as well morbidity rates for the binomial maternal-fetal , due to long-term neurological sequels. Although mortality due to Amniotic Fluid Embolism has decreased in recent surveys, it still remains among the most important causes of maternal death in the world. The syndrome seems to have a higher incidence than has been published because only the most exuberant clinical cases are reported. In Brazil, the underregistration of death declaration, hampers further the real monitoring of complications. Several revisions were written on the topic but the pathogenesis of the syndrome remains unclear. The AFE has still complex pathophysiology that leads to pulmonary hypertension, heart failure and disseminated intravascular coagulation. The diagnosis is based on clinical signs and symptoms after excluding other possibilities, because there is still not any laboratory or imaging method able to confirm the Amniotic fluid embolism. After initial suspicion, the treatment should be the institution of early and effective life suportive actions.In more than 60% of the cases, at the time of diagnosis, the fetus is still in maternal uterus, and its extraction mustbe done immediately, as long as allowed considering lung maturity . In this revision , we would like to make other considerations discussing the hypothesis that the great majority of the most severe cases are not only related to embolic phenomena, but to also humoral anachanges caused by contaminant factors, such as the presence of meconium in embolized content.

Release of arachidonic acid metabolites from blood by cultivation of human amniotic fluid with oneself blood / 中国病理生理杂志

AIM: To investigate the effect of human amniotic fluid on the release of thromboxane A 2 (TXA 2), prostaglandin I 2 (PGI 2) and Leukotriene C 4(LTC 4) from blood cells. METHODS: 1 mL human amniotic fluid and 10 mL oneself blood collected from 38-41 weeks with cesarean section were cultured at 37℃ for 30 min, and then centrifuged. The supernatants were taken and stored at -70℃. TXB 2 and 6-Keto-PGF 1? of the superntants were determined by radioimmunoassay and LTC 4 by enzyme immunoassay. RESULTS: It was found that the levels of TXB 2 and LTC 4 in blood were elevated from (63.5?52.0) ng/L and (40.1?39.2) ng/L to (189.1?102.0) ng/L and (293.5?206.1) ng/L respectively (P0.05).CONCLUSION: Amniotic fluid might stimulate the release of TXA 2 and LTC 4 from blood, it might affect the balance of TXA 2 and PGI 2 in blood, which might play an important role in the pathogenesis of amniotic fluid embolism.