Amniotic fluid embolism: analysis of the national registry

Electrical impedance tomography may optimize ventilation in a postpartum woman with respiratory failure

Amniotic fluid embolism is a rare peripartum complication with the sudden onset of haemodynamic instability, respiratory failure and coagulopathy during labour or soon after delivery. A 31-year-old woman with amniotic fluid embolism was treated with vasopressors, inotropes, intravenous fluid, tranexamic acid and ventilatory support. Assessment of respiratory impairment was made using conventional chest X-ray, computed tomography and electrical impedance tomography. The potential for electrical impedance tomography to improve monitoring and guide respiratory therapy is explored.

[Amniotic fluid embolism: report of the successful outcome of a case with inaugural cardiac arrest and early DIVC complicated by hemoperitoneum of iatrogen origin and bleeding of an hepatic adenoma]

Amniotic fluid embolism is a relatively rare clinical entity and with difficult medical recognition. However, it is the second leading cause of maternal mortality. We report here the case of a 32-year-old patient who underwent elective caesarean section complicated by an amniotic fluid embolism with cardiac arrest. The presence of a major disseminated intravascular coagulation favored the occurrence of a retroperitoneal hematoma of iatrogenic origin on attempt of femoral venous catheterization and that of hemoperitoneum on bleeding of an hepatic adenoma. The diagnostic of amniotic fluid embolism was confirmed by the presence of amniotic cells in the bronchoalveolar lavage. The patient survived without sequelae.

Placentophagia in humans and nonhuman mammals: causes and consequences

Afterbirth ingestion by nonhuman mammalian mothers has a number of benefits: (1) increasing the interaction between the mother and infant; (2) potentiating pregnancy-mediated analgesia in the delivering mother; (3) potentiating maternal brain opioid circuits that facilitate the onset of caretaking behavior; and (4) suppressing postpartum pseudopregnancy. Childbirth is fraught with additional problems for which there are no practical nonhuman animal models: postpartum depression, failure to bond, hostility toward infants. Ingested afterbirth may contain components that ameliorate these problems, but the issue has not been tested empirically. The results of such studies, if positive, will be medically relevant. If negative, speculations and recommendations will persist, as it is not possible to prove the negative. A more challenging anthropological question is "why don't humans engage in placentophagia as a biological imperative?" Is it possible that there is more adaptive advantage in not doing so?

Maternal cardiac arrest: an overview

Cardiac arrest in pregnancy is a rare event, and the speed of resuscitation response is critical to the outcome of both the mother and the fetus. The management of the unresponsive pregnant woman differs from that of the traditional adult resuscitation. In this article, causes of maternal arrest, management of proper cardiopulmonary arrest in pregnancy, and implementation of perimortem cesarean delivery are discussed.

Temporary extracorporeal circulatory support and pulmonary embolectomy for catastrophic amniotic fluid embolism

Amniotic fluid embolism is usually a life-threatening complication of an otherwise healthy pregnancy. Medical management of the coagulopathy and cardiovascular collapse is challenging and is often unsuccessful. We present a case and advocate the use of temporary circulatory support and pulmonary embolectomy in what would otherwise have been a fatal scenario.

Medical responsibility in the operating room: the example of an amniotic fluid embolism

Amniotic fluid embolism (AFE) continues to be one of the most feared complications of pregnancy. A healthy 32-year-old woman died during delivery after a normal 39-week third pregnancy. The family filed a complaint with a criminal court as the causes of death appeared unclear. No risk factor associated with AFE was identified. Clinical presentation was typical, including sudden onset of cardiovascular and respiratory symptoms. Autopsy confirmed the histological diagnosis of amniotic embolism and excluded an iatrogenic cause of death or anesthetic malpractice. This article highlights the value of both antemortem records and histological features in establishing the diagnosis of AFE and demonstrates the fundamental importance of autopsy in an unexpected death related directly or indirectly to a medical procedure.

Perinatal morbidity and risk of hypoxic-ischemic encephalopathy associated with intrapartum sentinel events

OBJECTIVE

To examine perinatal morbidity and rate of hypoxic-ischemic encephalopathy in infants exposed to intrapartum sentinel events.

STUDY DESIGN

Retrospective cohort study from 2000-2005. Perinatal mortality, perinatal morbidity and rate of hypoxic-ischemic encephalopathy were compared in 3 groups of infants exposed to different risk factors for perinatal asphyxia (sentinel events, nonreassuring fetal status, elective cesarean section).

RESULTS

Five hundred eighty-six infants were studied. Perinatal mortality was 6% in the sentinel event group and 0.3% in the nonreassuring fetal status group (relative risk, 2.4; 95% confidence interval, 1.95-2.94). Perinatal morbidity was 2-6 times more frequent in infants exposed to sentinel events; the incidence of hypoxic-ischemic encephalopathy was 10%, compared with 2.5% in the nonreassuring fetal status group (relative risk, 1.93; 95% confidence interval, 1.49-2.52). No infant in the elective cesarean section group died, had perinatal morbidity, or developed encephalopathy.

CONCLUSION

Intrapartum sentinel events are associated with a high incidence of perinatal morbidity and hypoxic-ischemic encephalopathy.

Treatment of pulmonary embolism: anticoagulation, thrombolytic therapy, and complications of therapy

During the last two decades, considerable progress in technology and clinical research methods have led to advances in the approach to the diagnosis, prevention, and treatment of acute venous thromboembolism (VTE). Despite this, however, the diagnosis is often delayed and preventive methods are often ignored. Thus, the morbidity and mortality associated with VTE remain high. The therapeutic approach to acute VTE is discussed in this article, with a particular focus on the intensive care unit setting.

Current concepts of immunology and diagnosis in amniotic fluid embolism

Amniotic fluid embolism (AFE) is one of the leading causes of maternal mortality and morbidity in developed countries. Current thinking about pathophysiology has shifted away from embolism toward a maternal immune response to the fetus. Two immunologic mechanisms have been studied to date. Anaphylaxis appears to be doubtful while the available evidence supports a role for complement activation. With the mechanism remaining to be elucidated, AFE remains a clinical diagnosis. It is diagnosed based on one or more of four key signs/symptoms: cardiovascular collapse, respiratory distress, coagulopathy, and/or coma/seizures. The only laboratory test that reliably supports the diagnosis is the finding of fetal material in the maternal pulmonary circulation at autopsy. Perhaps the most compelling mystery surrounding AFE is not why one in 20,000 parturients are afflicted, but rather how the vast majority of women can tolerate the foreign antigenic presence of their fetus both within their uterus and circulation?

Disseminated Intravascular Coagulation, Hemoperitoneum, and Reversible Ischemic Neurological Deficit Complicating Anaphylaxis to Prophylactic Antibiotics during Cesarean Delivery: A Case Report and Review of Literature

Routine use of prophylactic antibiotics reduces the risk of postcesarean fever and infections by over 50% in both nonelective and elective (scheduled) procedures. Although anaphylaxis to prophylactic antibiotics is rare, potentially fatal complications might occur. Herein, we present a case where disseminated intravascular coagulation and reversible ischemic neurological deficit complicated anaphylactic reactions to prophylactic antibiotics administered during cesarean delivery. A 27-year-old gravida 9, para 7 at 39(2)/7 weeks underwent elective repeat cesarean delivery and bilateral tubal ligation. Her surgery was complicated by intraoperative hypotension, generalized itching, and urticarial skin rash consistent with anaphylactic reaction upon administering prophylactic cefazolin. In the recovery room, she continued to be hemodynamically unstable despite energetic resuscitation. Hemoperitoneum was suspected, and laboratory evaluation indicated disseminated intravascular coagulation. Abdominal exploration revealed massive hemoperitoneum, but there was no source of active bleeding noted. The postoperative course was complicated by reversible ischemic neurological deficit, which resolved on expectant management. Disseminated intravascular coagulation and reversible ischemic neurological deficit may complicate anaphylactic reaction to prophylactic antibiotics administered during cesarean delivery. Immediate recognition and intervention is crucial for a successful outcome.

Aortic compression and cross clamping in a case of placenta percreta and amniotic fluid embolism: a case report

Amniotic fluid embolism (AFE, also known as anaphylactoid syndrome of pregnancy) at the time of surgery for placenta percreta has been previously reported. We report here a case in which AFE and associated cardiac arrest occurred following a hysterectomy for placenta percreta. In this case, subhepatic manual aortic compression during the cardiac arrest and chest compressions followed by infrarenal aortic cross-clamping during volume infusion and reversal of the coagulopathy were associated with a successful resuscitation and good maternal outcome.

Clinical review: Special populations--critical illness and pregnancy

Critical illness is an uncommon but potentially devastating complication of pregnancy. The majority of pregnancy-related critical care admissions occur postpartum. Antenatally, the pregnant patient is more likely to be admitted with diseases non-specific to pregnancy, such as pneumonia. Pregnancy-specific diseases resulting in ICU admission include obstetric hemorrhage, pre-eclampsia/eclampsia, HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome, amniotic fluid embolus syndrome, acute fatty liver of pregnancy, and peripartum cardiomyopathy. Alternatively, critical illness may result from pregnancy-induced worsening of pre-existing diseases (for example, valvular heart disease, myasthenia gravis, and kidney disease). Pregnancy can also predispose women to diseases seen in the non-pregnant population, such as acute respiratory distress syndrome (for example, pneumonia and aspiration), sepsis (for example, chorioamnionitis and pyelonephritis) or pulmonary embolism. The pregnant patient may also develop conditions co-incidental to pregnancy such as trauma or appendicitis. Hemorrhage, particularly postpartum, and hypertensive disorders of pregnancy remain the most frequent indications for ICU admission. This review focuses on pregnancy-specific causes of critical illness. Management of the critically ill mother poses special challenges. The physiologic changes in pregnancy and the presence of a second, dependent, patient may necessitate adjustments to therapeutic and supportive strategies. The fetus is generally robust despite maternal illness, and therapeutically what is good for the mother is generally good for the fetus. For pregnancy-induced critical illnesses, delivery of the fetus helps resolve the disease process. Prognosis following pregnancy-related critical illness is generally better than for age-matched non-pregnant critically ill patients.

Intraoperative cell salvage in obstetrics

The use of Intraoperative Cell Salvage (ICS) in obstetrics has been slow to develop as a result of theoretical concerns relating to amniotic fluid embolism and fetal red cell contamination. In this article we examine the current UK position on the use of ICS in this clinical speciality and the recommendations for its safe and appropriate use.

Amniotic fluid embolism: A diagnostic dilemma

Amniotic fluid embolism (AFE) is a rare obstetric catastrophe with an incidence of 7.7 per 100 000 deliveries and mortality as high as 60% to 80%. We describe a case of perioperative cardiac arrest in a young parturient undergoing an emergent cesarean section. Just after delivery of live healthy male baby, patient developed disseminated intravascular coagulation not responding to resuscitation with fluids and blood products. Her autopsy revealed edematous lungs with amniotic fluid debris within pulmonary vessels thus establishing the diagnosis of AFE. Amniotic fluid embolism is life threatening and difficult to predict or prevent condition, which should be always be kept in mind in a parturient with sudden cardiovascular collapse, so that resuscitation commences immediately, as early intervention is essential for a positive outcome.

Severe hypotension and water intoxication developed after an accidental oxytocin overdose in a morbidly obese patient undergoing cesarean section -A case report-

We present a 32-year-old, extremely obese, pregnant woman who developed severe hypotension and water intoxication after an accidental injection of large bolus of oxytocin during cesarean section under general anesthesia. The patient was initially thought to have an amniotic fluid embolism because of the abrupt hemodynamic changes developed immediately after fetal delivery and lack of recognition of medication error. It is highly recommended that careful attention should be paid not only to the possibility of hemodynamic deterioration and water intoxication if oxytocin is given rapidly in excessive doses, but to the confirmation of the proper use of the drug before it is injected.

Successful recovery from delayed amniotic fluid embolism with prolonged cardiac resuscitation

Amniotic fluid embolisms (AFE) are one of the most fatal complications of pregnancy. We describe a case of AFE that occurred 2 h after vaginal delivery at 41 weeks of gestation. The diagnosis of AFE was made by symptoms of dyspnea, coagulopathy, and severe hypotension. ZnCP-1, the characteristic component of meconium, was elevated in the serum. Cardiac compressions after repeated cardiac arrests were required during the initial 2 h of resuscitation. Primary resuscitation was performed with airway management and aggressive fluid management, including infusion of 33 units of red cell concentrates and 57 units of fresh frozen plasma. The patient recovered without any aftereffects. This case report warrants that AFE should be considered when coagulopathy and dyspnea are observed during the postpartum period.

Ischemic Stroke during Pregnancy and Puerperium

Ischemic stroke during pregnancy and puerperium represents a rare occurrence but it could be a serious and stressful event for mothers, infants, and also families. Whenever it does occur, many concerns arise about the safety of the mother and the fetus in relation to common diagnostic tests and therapies leading to a more conservative approach. The physiological adaptations in the cardiovascular system and in the coagulability that accompany the pregnant state, which are more significant around delivery and in the postpartum period, likely contribute to increasing the risk of an ischemic stroke. Most of the causes of an ischemic stroke in the young may also occur in pregnant patients. Despite this, there are specific conditions related to pregnancy which may be considered when assessing this particular group of patients such as pre-eclampsia-eclampsia, choriocarcinoma, peripartum cardiomiopathy, amniotic fluid embolization, and postpartum cerebral angiopathy. This article will consider several questions related to pregnancy-associated ischemic stroke, dwelling on epidemiological and specific etiological aspects, diagnostic issue concerning the use of neuroimaging, and the related potential risks to the embryo and fetus. Therapeutic issues surrounding the use of anticoagulant and antiplatelets agents will be discussed along with the few available reports regarding the use of thrombolytic therapy during pregnancy.

A noninvasive evaluation analysis of amniotic fluid embolism and disseminated intravascular coagulopathy

OBJECTIVE

Amniotic fluid embolism (AFE) is a complication of pregnancy with a high mortality rate. The diagnosis of AFE is currently based on clinical findings, acute respiratory distress, cardiovascular collapse during labor and delivery, and immediate massive postpartum hemorrhaging. The serum biological markers are unreliable, and their detection requires a long time intervals for result. An early diagnosis is very important and prompts the clinical management of the condition.

STUDY DESIGN AND RESULTS

We present here a noninvasive method (time frequency, entropy) to analyze heart rate variability (HRV). 3D-Spectrogram and entropy were derived from the RR interval of two pregnant subjects with AFE and disseminated intravascular coagulation (DIC) survived after delivering normal babies admitted to the Taiwan Seventh-day Adventists Hospital, and the entropy values were compared with those of 105 healthy pregnant subjects in the same hospital.

CONCLUSIONS

We show that these methods can be successfully applied to the diagnosis of AFE and predict the prognosis of DIC. We also show that CT scans can be applied to the diagnosis of pulmonary embolism, eliminating the need to pathology.

Do uterotrophic drugs increase the risk of fatal hemorrhagic brain stroke?

OBJECTIVE

To evaluate whether uterotrophic agents increase the risk of fatal hemorrhagic brain stroke.

METHODS

Between 1991 and 1992, there were 230 maternal deaths among 2,420,000 pregnant women in Japan and the causes of these deaths was investigated in 1994. Using information provided in this report, we identified 35 women who died from or were assumed to die from hemorrhagic brain stroke. We assumed that 93% of women would have tried vaginal delivery. The risk of fatal hemorrhagic brain stroke after uterotrophic agent use was calculated according to the assumption that 5.0-40% of women received uterotrophic agents.

RESULTS

Use of uterotrophic agents for induction/augmentation of labor was confirmed in five (14.3%) of the 35 women who died from hemorrhagic brain stroke. The incidence of fatal brain stroke after the use of uterotrophic agents was only significantly higher than that for spontaneous hemorrhagic brain stroke if these agents were administered in ≤ 6.0% of women.

CONCLUSIONS

Because more than 6.0% of women received uterotrophic agents, these agents are unlikely to increase the risk of fatal hemorrhagic brain stroke.

Amniotic fluid embolism that took place during an emergent Cesarean section -A case report-

Amniotic fluid embolism (AFE) is a rare but fatal obstetric emergency, characterized by sudden cardiovascular collapse, dyspnea or respiratory arrest and altered mentality, disseminated intravascular coagulation (DIC). It can lead to severe maternal morbidity and mortality, but the prediction of its occurrence and treatment are very difficult. We experienced a case of AFE during emergent Cesarean section in a 40⁺⁶ weeks healthy pregnant woman, age 33. Sudden dyspnea, hypotension, signs of pulmonary edema and DIC were developed during Cesarean section, and cardiac arrest followed after these events. The course of these events was so rapid and catastrophic, which was consistent with AFE. Thus, we report this case precisely and review pathophysiology, diagnosis, treatment of AFE by referring to up-to-date literatures.

Surgical treatment of an amniotic fluid embolism with cardiopulmonary collapse

Amniotic fluid embolism is a rare but devastating condition associated with a very high rate of morbidity and mortality. The treatment has traditionally been aggressive supportive care. We report a case of a term pregnant woman with complete cardiovascular collapse secondary to a paradoxical amniotic fluid embolism. The embolism was seen on transesophageal echocardiogram during an emergency Cesarean section as a free-floating interatrial clot through a patent foramen ovale. She was subsequently and successfully treated with immediate cardiopulmonary bypass, thromboembolectomy, and closure of the patent foramen ovale.

Amniotic fluid embolism-apropos two consecutive cases

Amniotic fluid embolism (AFE) is a sporadic, unpredictable, and usual fatal obstetric complication. The paper deals with two cases of maternal deaths because of AFE verified by medicolegal autopsy. In both the cases, several known risk factors associated with AFE, such as increased maternal age (41 and 35 years), diabetes, augmented labor, and cesarean delivery, were identified. Clinical features were typical, including sudden onset of cardiovascular and respiratory symptoms. In the patient who survived longer, both clinical and autopsy signs of disseminated intravascular coagulopathy were present, while they were absent in the case where death occurred rapidly. This paper describes briefly the particular features to look for at autopsy and stresses the importance of histology examination and staining techniques.

Amniotic fluid embolism

Amniotic fluid embolism (AFE) remains an enigmatic, but devastating obstetrical condition associated with significant maternal and newborn morbidity and mortality. Although our understanding of this condition is incomplete, research over the past 2 decades has altered traditional concepts of both the causation and pathophysiology of AFE. Although maternal treatment remains primarily supportive, prompt delivery of the fetus can substantially improve neonatal outcome after AFE-induced cardiac arrest. Newer biochemical markers may in the future enhance the specificity and sensitivity of this clinical diagnosis and could potentially lead to improved therapy.

Cell salvage as part of a blood conservation strategy in anaesthesia

The use of intraoperative cell salvage and autologous blood transfusion has become an important method of blood conservation. The main aim of autologous transfusion is to reduce the need for allogeneic blood transfusion and its associated complications. Allogeneic blood transfusion has been associated with increased risk of tumour recurrence, postoperative infection, acute lung injury, perioperative myocardial infarction, postoperative low-output cardiac failure, and increased mortality. We have reviewed the current evidence for cell salvage in modern surgical practice and examined the controversial issues, such as the use of cell salvage in obstetrics, and in patients with malignancy, or intra-abdominal or systemic sepsis. Cell salvage has been demonstrated to be safe and effective at reducing allogeneic blood transfusion requirements in adult elective surgery, with stronger evidence in cardiac and orthopaedic surgery. Prolonged use of cell salvage with large-volume autotransfusion may be associated with dilution of clotting factors and thrombocytopenia, and regular laboratory or near-patient monitoring is required, along with appropriate blood product use. Cell salvage should be considered in all cases where significant blood loss (>1000 ml) is expected or possible, where patients refuse allogeneic blood products or they are anaemic. The use of cell salvage in combination with a leucocyte depletion filter appears to be safe in obstetrics and cases of malignancy; however, further trials are required before definitive guidance may be provided. The only absolute contraindication to the use of cell salvage and autologous blood transfusion is patient refusal.

Amniotic fluid embolism complicated by paradoxical embolism and disseminated intravascular coagulation

Amniotic fluid embolism is a rare syndrome with potentially lethal outcomes. Complications include cardiorespiratory failure, disseminated intra-vascular coagulation, seizures, neurological deficits, and death. A 34-year-old woman had amniotic fluid embolism complicated by paradoxical embolism and disseminated intravascular coagulation. Emergency cesarean section followed by cardiopulmonary bypass with removal of the clot from the atria and closure of the patent foramen ovale was performed, resulting in a good outcome for both the mother and the baby. Subsequent treatment with anticoagulants for 6 months was recommended. A literature review revealed that this clinical scenario is rare but can be successfully managed by cardiopulmonary bypass and thromboembolectomy. Data on guidelines for the use of anticoagulation in this situation are limited.

Algorithm-based coagulation management of catastrophic amniotic fluid embolism

Amniotic fluid embolism (AFE) is a rare, but often catastrophic, complication of pregnancy and associated with severe coagulopathy. We present an algorithm-based approach in managing coagulopathy and hemorrhage in a fatal case of histopathologically proven AFE. Thrombelastometry was used for rapid evaluation of the coagulation status. Stop of extensive hyperfibrinolysis with tranexamic acid, stabilization of initial clot formation with high-dose fibrinogen and platelet transfusions, and use of prothrombin complex concentrate together with a 1: 1 transfusion regimen of red packed cells and fresh frozen plasma was successful to control diffuse bleeding and restore clot firmness after hysterectomy. Stable clotting situation was maintained despite further clinical deterioration and development of multiple organ failure in this patient.