|
|
 |
|
SYMPOSIUM: EMBOLISM IN THE INTENSIVE CARE UNIT |
|
Year : 2013 | Volume
: 3
| Issue : 1 | Page : 51-57 |
|
Amniotic fluid embolism
Cattleya Thongrong1, Pornthep Kasemsiri2, James P Hofmann3, Sergio D Bergese4, Thomas J Papadimos5, Vicente H Gracias6, Michael D Adolph7, Stanislaw P. A. Stawicki8
1 Department of Anesthesiology, Centre for Palliative Care, The Ohio State University College of Medicine, Columbus, OH, USA; Department of Anesthesiology, Srinagarind Hospital, Faculty of Medicine at the Khon Kaen University, Khon Kaen, Thailand 2 Department of Otolaryngology/Head and Neck Surgery, Centre for Palliative Care, The Ohio State University College of Medicine, Columbus, OH, USA; Department of Otorhinolaryngology, Srinagarind Hospital, Faculty of Medicine at the Khon Kaen University, Khon Kaen, Thailand 3 Department of Anesthesiology, University of Toledo College of Medicine, Toledo, OH, USA 4 Department of Anesthesiology; Department of Neurological Surgery, Centre for Palliative Care, The Ohio State University College of Medicine, Columbus, OH, USA 5 Department of Anesthesiology, Centre for Palliative Care, The Ohio State University College of Medicine, Columbus, OH, USA 6 Deparment of Surgery, Division of Trauma/Surgical Critical Care, UMDNJ-Robert Wood Johnson University Hospital, New Brunswick, NJ, USA 7 Department of Surgery, Centre for Palliative Care, The Ohio State University College of Medicine, Columbus, OH, USA 8 Department of Surgery, Division of Trauma, Critical Care and Burn, The Ohio State University College of Medicine, Columbus, OH, USA
Date of Web Publication | 22-Mar-2013 |
Correspondence Address: Stanislaw P. A. Stawicki Department of Surgery, Division of Trauma, Critical Care, and Burn, The Ohio State University College of Medicine, Suite West Avenue, Columbus, USA
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/2229-5151.109422
Abstract | | |
Amniotic fluid embolism (AFE) is an unpredictable and as-of-yet unpreventable complication of maternity. With its low incidence it is unlikely that any given practitioner will be confronted with a case of AFE. However, this rare occurrence carries a high probability of serious sequelae including cardiac arrest, ARDS, coagulopathy with massive hemorrhage, encephalopathy, seizures, and both maternal and infant mortality. In this review the current state of medical knowledge about AFE is outlined including its incidence, risk factors, diagnosis, pathophysiology, and clinical manifestations. Special attention is paid to the modern aggressive supportive care that resulted in an overall reduction in the still alarmingly high mortality rate of this devastating entity. The key factors for successful management and resolution of this disease process continue to be sharp vigilance, a high level of clinical suspicion, and rapid all-out resuscitative efforts on the part of all clinicians involved in the medical care of the parturient. Keywords: Amniotic fluid embolism, diagnosis, focused summary, management
How to cite this article: Thongrong C, Kasemsiri P, Hofmann JP, Bergese SD, Papadimos TJ, Gracias VH, Adolph MD, Stawicki SP. Amniotic fluid embolism. Int J Crit Illn Inj Sci 2013;3:51-7 |
How to cite this URL: Thongrong C, Kasemsiri P, Hofmann JP, Bergese SD, Papadimos TJ, Gracias VH, Adolph MD, Stawicki SP. Amniotic fluid embolism. Int J Crit Illn Inj Sci [serial online] 2013 [cited 2023 Mar 24];3:51-7. Available from: https://www.ijciis.org/text.asp?2013/3/1/51/109422 |
Introduction | |  |
Amniotic fluid embolism (AFE) is a rare event that affects parturients during delivery or in the immediate postpartum period. Clinical sequelae of this unpredictable and unpreventable entity are often devastating with significant associated morbidity and mortality. [1] Its first modern description was published in the 1920's [2] with a further report recognizing AFE as a syndrome in the 1940s. [3],[4] The reported incidence of AFE is between 0.001% and 0.013% among patients admitted for delivery. [5],[6] Due to the uncommon occurrence of AFE the need exists for a high level of clinical suspicion among practitioners. Although specialists in obstetrics are the most likely to encounter this clinical entity; emergency medicine physicians, surgeons, anesthesiologists, and intensivists should also be familiar with the diagnosis and management of AFE. In this review we discuss the pathophysiology, clinical presentation, and diagnostic and therapeutic considerations associated with AFE.We also highlight the critical care aspects of affected patient care, and focus on the high index of clinical suspicion required to promptly recognize and treat this cause of 10-26% of maternal deaths. [3],[7],[8]
Incidence of Amniotic Fluid Embolism | |  |
The reported incidence of AFE varies because of a wide spectrum of presenting signs and symptoms, as well as lack of a standardized approach to diagnostic evaluation of patients with suspected AFE. As previously enumerated, the incidence of AFE is fortunately low, between 1.9 and 11 per 100,000 admissions for delivery. [3],[5] This translates roughly into a relatively broad range of 1 in 4,500 to 1 in 80,000 pregnancies. [5],[6] The incidence of AFE was reported to be significantly higher in patients who had cesarean section (22/100,000 deliveries) than in patients who had vaginal delivery (8/100,000). [6] The incidence is also significantly higher in women aged 30-39 years (17/100,000) than in women aged 15-29 years (8/100,000). [6] Despite relatively unchanged incidence, it has been noted that the mortality associated with AFE has decreased significantly in the recent past. [7]
Pathophysiology of amniotic fluid embolism
Amniotic fluid embolism syndrome is thought to occur through three different pathophysiologic mechanisms. These three contributory pathways are: (a) mechanical obstruction of vessels caused by AFE; (b) a subsequent inflammatory effect by AFE on the maternal circulatory system; and (c) an as of yet poorly understood immunologic mechanism.
The clinical syndrome itself is precipitated when amniotic fluid is able to breach the physical barrier between the maternal and fetal environments as a result of uterine trauma. Autopsy reports from fatal cases of AFE report epithelial squamous cells, lanugo hair, and fat from vernix or infantile mucin in the maternal pulmonary vasculature. Commonly suspected sites of amniotic fluid entry into the maternal circulation are small tears in the endocervix and lower uterine segment - both frequently seen during labor and delivery. [9] Amniotic fluid, once forced into the maternal systemic circulation, may lead to circulatory obstruction, including that of the pulmonary circulation. [4],[9],[10]
There is evidence that once AFE has occurred certain biochemical mediators associated with it can trigger systemic inflammatory responses. Clinical manifestations of AFE may be similar to that of anaphylactic or septic shock. In fact, Clark et al.[11] proposed changing the name of the syndrome from "amniotic fluid embolus" to "anaphylactoid syndrome of pregnancy". Amniotic fluid has both vasoactive and procoagulant characteristics that have been proposed to be mediated by prostaglandins, endothelin, platelet activating factor, leukotrienes, bradykinin and tissue factor. [9],[10] Consequently, clinical manifestations of AFE including coagulopathy, increased vascular permeability, vasoconstriction of pulmonary, systemic and coronary vessels, and bronchospasm could all be seen to proceed by a humoral mechanism. [10]
A possible immunologic mechanism has been proposed as a third contributing factor, based on the many similarities that exist between clinical and hemodynamic findings of AFE and anaphylactic shock. [12] The complement system may play a role in this mechanism of the AFE syndrome. [13],[14] However, our understanding of the immunologic pathophysiology of AFE is in its early stages and further work needs to be done.
Amniotic fluid embolism: Risk factors
The United Kingdom Obstetric Surveillance System [UKOSS] reported that elevated risk for AFE is associated with the following factors: (a) induction of labor (relative risk of 3.86); (b) Caesarean section (relative risk of 12.5); (c) placenta previa and placental abruption (3-10 times greater risk); (d) eclampsia; (e) multiple pregnancies; and (f) maternal age ≥35 years (possibly related to abnormal placental invasion and predisposition to disruption of the uterine vasculature). [15] These findings suggest that if induction and caesarean section were avoided the incidence AFE could be significantly reduced. It has also been observed that patient age <19 years may confer a protective effect against the syndrome. Direct attribution of AFE to any one of these factors is probably an oversimplification and other variables are likely involved.
Clinical manifestations
Amniotic fluid embolism can take a variety of clinical presentations [Table 1], making it truly a "great mimicker" of various other disease states. The sequelae of AFE can be truly devastating, and it can affect many organ systems. There may be little to no warning signs preceding the full-blown syndrome. It usually occurs as a complication of childbirth, presenting during delivery, immediately postpartum, or as late as 48 hours after. It can also occur at other points during pregnancy, including during transabdominal amniocentesis, cervical suture removal, and as a result of blunt abdominal trauma. [15],[16]  | Table 1: Common signs and symptoms associated with amniotic fluid embolism
Click here to view |
Classic presenting signs and symptoms may include sudden anxiety, agitation, dyspnea, hypotension, cyanosis, cardiopulmonary arrest, coagulopathy, and seizures. [15] It is not uncommon for AFE to progress rapidly from a sudden decrease in oxygen saturation and end-tidal carbon dioxide, to the development of cardiovascular collapse. In the later phase, coagulopathy and hemorrhage can occur. Disseminated intravascular coagulation (DIC) should also be considered, though it is not seen universally among patients with AFE. Finally, tissue injury and multi organ failure occur. Currently, no reliable preventive approaches for AFE are known, but the authors strongly encourage practitioners to be familiar with established risk factors and implement this knowledge in their practices.
Atypical manifestations of AFE can take a number of forms. One such form includes isolated coagulopathy with either a sudden or a gradual onset. The report of maternal deaths within the UK found that parturients who died from AFE frequently had premonitory symptoms before complete collapse including feeling cold, restlessness, and respiratory distress. This may give a clue to diagnosis, before cardiac arrest and DIC occur. [17]
Progression of systemic changes in AFE
The acute phase
Occurs within the initial 30 minutes. Amniotic fluid and fetal cells in the circulation can cause severe pulmonary hypertension secondary to pulmonary vasoconstriction with resulting right heart failure, hypotension and hypoxemia. In AFE hypoxemia is the most common manifestation of respiratory failure. This occurs because of severe ventilation/perfusion (V/Q) mismatch associated with acute pulmonary hypertension, although hypoventilation can also occur. [18],[19] The initial acute hypoxemia can lead to ischemic myocardial injury and this can be aggravated by the effect of direct myocardial depressant factors present in the amniotic fluid. The influence of humoral factors can contribute to inflammatory capillary leak, leading to non-cardiogenic pulmonary edema and bronchospasm. [11],[20] Victims of AFE frequently succumb during the acute phase of the insult. [21]
The late phase
This phase is seen in survivors of the acute phase. The acute insult of AFE can be followed by the development of left heart failure within an hour. This left heart failure is likely secondary to the leftward shift of the interventricular septum because of right heart failure/strain. Severe hypotension results - compounded by the active vasodilatory process, and hemorrhage (if present). Primary lung injury (from mechanical circulatory obstruction or inflammatory/immunologic mechanisms) often leads to acute respiratory distress syndrome (ARDS). [22]
Coagulopathy is related to either a consumptive process or massive fibrinolysis. Lockwood et al. found a procoagulant tissue factor in the amniotic fluid that can trigger the coagulation cascade. [23] Coagulopathy may be one of the most prominent signs of AFE, it usually appears within 4 hours of the initial presentation. The end result may be massive bleeding similar to that seen in disseminated intravascular coagulation, which may in fact be present. The development of hemorrhagic shock is a distinct possibility.
One of the most devastating long-term consequences of AFE is neurologic dysfunction. As many as 85% of survivors demonstrate residual neurologic deficits. [3] In fact, neurologic complications often represent the most severe of post-AFE sequelae. It is thought that both the encephalopathy and seizures associated with AFE are secondary to hypoxia. [24]
Clinical diagnosis
The clinical description of AFE has remained fairly constant over the past four decades [Table 1] and [Table 2]. Amniotic fluid embolism essentially remains a diagnosis of exclusion; however, a more detailed examination of many AFE cases does show certain common themes. The diagnosis usually relies on the presence of one or more of four otherwise unexplained events occurring during parturience [15],[25] [Table 1] and [Table 3]. These diagnostic indicators are (a) acute hypotension, (b) cardiac arrest, (c) acute hypoxemia or respiratory distress and (d) severe hemorrhage or coagulopathy. Any episodes that occur during labor, caesarean deliveries, dilation and evacuation, or within 30 minutes postpartum without other explanations should alert the practitioner to the possibility of AFE.
Most patients initially present with abrupt cardiac and respiratory failure. Early signs such as dyspnea, altered consciousness and restlessness may be associated with hypoxia and impending cardiopulmonary failure. Furthermore, some case reports have described fetal bradycardia occurring early at the onset of AFE. [26],[27],[28] Other signs may be severe hemorrhage and coagulopathy. [29] It should also be noted that uterine atony has been reported by some authors. [30],[31] Again, many of the signs and symptoms of AFE are non-specific, and alternative diagnoses need to be ruled out.
Laboratory abnormalities associated with AFE
Several diagnostic tests have been put forth as useful in the diagnosis of AFE. However, no single diagnostic test can confirm or disprove the presence of AFE. Clinically useful but non-specific laboratory data includes: (a) arterial blood gas analysis to determine adequacy of ventilation and degree of hypoxemia; (b) comprehensive blood cell count including platelet count; (c) coagulation profile to assess platelet function, prothrombin time, International Normalized Ratio (INR), activated partial thromboplastin time, and fibrinogen levels. Thromboelastography (TEG) may also be useful.
The finding of amniotic fluid debris in the maternal pulmonary microvasculature is considered highly suggestive, especially when fetal squamous cells/debris and neutrophils are found in blood samples collected through the distal port of a pulmonary artery catheter. [32],[33] One investigator found transient intracardiac thrombi to be associated with AFE. [34] Kanayama et al. reported an association between AFE and increases in zinc coproporphyrin (an amniotic fluid component) in cytological analysis of maternal plasma. [35] Other investigators have demonstrated that TKH-2 antibody and serum sialyl-Tn (STN) assays have a good sensitivity for supporting the diagnosis of AFE. [36] Furthermore, Nishio et al hint that AFE may be associated with elevated serum tryptase levels, pointing to potential mechanistic similarities between A0 FE and anaphylaxis. [37] This evidence while supportive is not definitive, as some investigators describe the amniotic fluid components to be commonly present in maternal circulation without clinical evidence of AFE syndrome. [38],[39] Additionally, obstetric hemorrhage patients receiving autotransfusion containing up to 1% fetal squamous cells in approximately 20% of cases demonstrated no obvious association with AFE. [40]
Other diagnostic adjuncts in AFE
Adjunctive tests may be helpful with the diagnosis and treatment of AFE. An electrocardiogram may show right heart strain and arrhythmia. Chest X-ray findings will detect evidence of pulmonary edema with interstitial and alveolar infiltrates distributed bilaterally. Transesophageal echocardiography (TEE) is beneficial to demonstrate regional wall motion abnormalities, evaluate valve function, ejection fraction, right-sided pressures, chamber size, and visualization of debris. In two case reports during the acute phase of AFE, TEE findings revealed severe pulmonary hypertension and acute right ventricular failure with a leftward deviation of the interatrial and interventricular septa. [18],[19]
Clinical management
At our present level of understanding all recommendations are treatment oriented, as there are no effective prophylactic options to prevent the development of AFE. Early recognition and prompt initiation of proper management is critical in optimizing outcomes for the patient with AFE. The treatment is supportive. The airway should be rapidly controlled and therapy undertaken to prevent or correct hypoxemia. Aggressive resuscitative efforts should be pursued to support and maintain hemodynamic sufficiency, and ensure adequate tissue perfusion. In the face of severe hemorrhage coagulopathies must be treated [Table 4].
To reduce the impact of aorto-caval compression on venous return, left uterine displacement should be done either manually or by placing a wedge under the parturient's right hip. Moreover, the Managing Obstetric Emergencies and Trauma (MOET) course recommends that fetal delivery (i.e., perimortem caesarean section or PMCS) be undertaken within 5 minutes of maternal cardiac arrest to decrease fetal toxicity and improve resuscitation efforts by removing aorto-caval compression. This will also potentially facilitate the efficacy of cardiopulmonary resuscitation. [41],[42] The fetus should be continuously monitored for any signs of hypoxia or distress.
In general, an approach based on traditional A-B-Cs (i.e., airway-breathing-circulation) of life support is the safest way to proceed. Immediate administration of high flow oxygen to prevent hypoxia is critical. Depending on patient status, this may be accomplished via high flow nasal cannula, face-mask, non-invasive positive pressure ventilation, or bag-valve mask ventilation. Most patients will require endotracheal intubation and positive pressure ventilation with 100% oxygen - at least initially. The decision to intubate is better made earlier than later. In severe cases, advanced ventilatory strategies may be required to treat severe hypoxia, non-cardiogenic pulmonary edema or ARDS. Besides lung protective strategies with use of a conventional ventilator, other approaches such as high frequency oscillatory ventilation, or even extracorporeal membrane oxygenation (ECMO) may be required. Veno-venous ECMO intervention for purely pulmonary support and veno-arterial EMCO intervention for cardiac support (with or without pulmonary decompensation) should be considered. [43] The potential airway difficulties present in a parturient should be kept in mind and physicians should be ready to secure the airway by use of a fiberoptic scope or even tracheotomy.
After the airway and respiratory status have been addressed, management focuses on treatment of hypotension and restoration of maternal circulation. Besides two large bore intravenous lines, central venous access should be established with serious consideration given to the use of a pulmonary artery catheter. Also, an arterial line and a urinary catheter should be placed to help guide therapy. Recent reports suggest that the use of transthoracic echocardiography or TEE may be beneficial when evaluating left ventricular contractility and filling. These modalities may also be useful in guiding the administration of intravenous fluid therapy and/or vasopressor/inotrope administration. [18],[19]
The physician should rapidly administer isotonic solutions to maximize preload. Vasopressors and inotropes will usually be needed, as refractory hypotension is highly probable. In the early phases of AFE circulatory vasodilation occurs. Phenylephrine and vasopressin may be appropriate therapies. Inotropic support, including dobutamine, dopamine, epinephrine, or norepinephrine may be required to treat ventricular contractile impairment. Milrinone may be an appropriate choice for right heart support through its positive effect on inotropy as a phosphodiesterase inhibitor, and through its vasodilatory effect on the pulmonary vasculature. Inhaled nitric oxide or inhaled epoprostenol should be considered for pulmonary vasodilation to treat refractory hypoxemia and to unload the right ventricle. Should this strategy fail, an intraaortic balloon pump, right ventricular assist device and/or ECMO (see above) should be considered. [18],[20],[26]
Hemorrhage in the setting of AFE should prompt early and aggressive blood product administration. Packed red blood cells and platelets should be administered to maintain oxygen carrying capacity and prevent thrombocytopenic bleeding. In cases of persistent bleeding, coagulopathy, or DIC treatment should proceed with a combination of fresh frozen plasma, cryoprecipitate, fibrinogen, and factor replacement. The exact products to be administered should be guided by laboratory studies, which may include fibrinogen levels, functional platelet counts, and thromboelastogram (TEG) as well as the standard INR and PTT. The use of recombinant activated factor VII has been reported in patients with AFE and bleeding unresponsive to conventional blood product therapy; however, due to significantly worse associated outcomes, factor VIIa should be restricted to cases where hemorrhage cannot be stopped by massive blood component replacement. [44] Antifibrinolytic drugs such as tranexamic acid or aminocaproic acid have been used in the past for obstetrical bleeding, but their efficacy in AFE is undetermined. [45],[46]
Medical therapy should be provided for uterine atony. If the bleeding cannot be controlled, hysterectomy may be necessary, but uterine artery embolization has been described in selected cases. [47] After initial stabilization, almost all patients with AFE require transfer to the intensive care unit. High-quality, modern maternal care using targeted approaches to potential sequelae and complications of AFE is the likely reason for improving outcomes associated with AFE. [15]
Prognosis and outcomes
Overall prognosis of patients with AFE, although significantly better since the advent of modern critical care capabilities and end-organ support, continues to be relatively poor. Mortality rate, although significantly lower than the previously reported range of approximately 60%, continues to be unacceptably high in the 20-40% range. [22] Chronic sequelae of end-organ dysfunction may be significant. Moreover, most of the survivors display some degree of neurologic impairment. [22] The perinatal death rate associated with AFE is also high (between 20-25%) with only 50% of surviving neonates being neurologically intact. [22] Among survivors, there are no data with regards to the risk for any subsequent AFE episodes in future pregnancies.
Pain and palliative considerations
Given potentially catastrophic nature of the AFE and the high risk for mortality, palliative critical care may be initiated concurrently with obstetrical critical care measures to relieve symptoms, distress, and facilitate communications between providers and the patient/family. The principles of palliative critical care can be applied by the obstetrical and intensivist team. [48] For patients with irreversible disease or uncertain prognosis, the complexities of palliative and end-of-life care warrant a consultation with specialist palliative care physicians, nurses, chaplains, and social workers. Optimal management requires teamwork, and obstetrical and critical care specialists should advise palliative care colleagues that of those maternal patients who do not survive, 25% die in the first hour, and approximately 80% succumb within the first 10 hours, [49],[50] with an associated high perinatal morbidity and mortality. As such, the consequences to the family are truly devastating. Interdisciplinary palliative care teams also have expertise in issues of grief, loss, and bereavement to support the complex needs of the family and clinicians experiencing the tragedy of a fatal AFE.
When providing palliation for a dying patient, opioids are the agents of choice to pharmacologically manage pain and dyspnea, and haloperidol to manage delirium of critical illness. [48] Terminal anxiety will usually respond to benzodiazepines in the majority of cases. The above symptoms are common to patients in critical care settings, should be assessed frequently, and are most distressing to both patients and families. Continuous symptoms warrant achieving a steady state utilizing regularly scheduled pharmacotherapy. Additional medications for acute exacerbations or refractory symptoms should be available in order for the bedside nurse to provide relief. Terminal anxiety and delirium are not relieved by opioid agents such as morphine injections or infusions, and high doses of opioids may actually worsen these symptoms. If withdrawal of futile technological support is indicated, then the pharmacological, staff training, and family communications need to become more complex and detailed. [51],[52] Loss of a family member, including critical care mortality, is often associated with post-traumatic stress symptoms among surviving relatives, [53] and these symptoms may be mitigated by optimization of palliative critical care communications via the facilitation of frequent family meetings with clinical teams. [54] Key competencies in the area of palliative critical care require active listening skills and compassion. [55] Enhanced bereavement care, with a high level of overall bereavement services given to family survivors in the obstetrical or critical care unit has the potential to improve general satisfaction with care. [56] Referral to counseling services and various support groups may be helpful as well.
Conclusions | |  |
AFE remains one of the most feared and devastating complications of pregnancy. Its presentation is variable and onset is unpredictable and largely non-preventable. Better knowledge of AFE on part of all members of the healthcare team is therefore crucial as it facilitates early recognition, aggressive management, and possibly improves the survival of both the mother and the child. Awareness of the syndrome and advances in intensive care medicine have been key to improving outcomes, although much needs to be done to further reduce both the morbidity and mortality associated with AFE.
References | |  |
1. | Martin RW.Amniotic fluid embolism. Clin Obstet Gynecol 1996;39:101-6.  [PUBMED] |
2. | Albrechtsen OK, Trolle D. A fibrinolytic system in human amniotic fluid. Acta Haematol 1955;14:376-82.  [PUBMED] |
3. | Moore J, Baldisseri MR. Amniotic fluid embolism. Crit Care Med 2005;33 Suppl 10:S279-85.  |
4. | Steiner PE, Lushbaugh CC. Landmark article, Oct. 1941: Maternal pulmonary embolism by amniotic fluid as a cause of obstetric shock and unexpected deaths in obstetrics. JAMA 1986;255:2187-203.  [PUBMED] |
5. | Knight M, Berg C, Brocklehurst P, Kramer M, Lewis G, Oats J, et al. Amniotic fluid embolism incidence, risk factors and outcomes: A review and recommendations. BMC Pregnancy Child birth 2012;12:7.  [PUBMED] |
6. | Stein PD, Matta F, Yaekoub AY. Incidence of amniotic fluid embolism: Relation to cesarean section and to age. J Womens Health (Larchmt) 2009;18:327-9.  [PUBMED] |
7. | Toy H. Amniotic fluid embolism. Eur J Gen Med 2009;6:108-15.  |
8. | Gilbert WM, Danielsen B. Amniotic fluid embolism: Decreased mortality in a population-based study. Obstet Gynecol 1999;93:973-7.  [PUBMED] |
9. | Davies S. Amniotic fluid embolus: A review of the literature. Can J Anaesth 2001;48:88-98.  [PUBMED] |
10. | Dudney TM, Elliott CG. Pulmonary embolism from amniotic fluid, fat, and air. Prog Cardiovasc Dis 1994;36:447-74.  [PUBMED] |
11. | Clark SL, Hankins GD, Dudley DA, Dildy GA, Porter TF. Amniotic fluid embolism: Analysis of the national registry. Am J Obstet Gynecol 1995;172:1158-67.  [PUBMED] |
12. | Clark SL. New concepts of amniotic fluid embolism: A review. Obstet Gynecol Surv 1990;45:360-8.  [PUBMED] |
13. | Conde-Agudelo A, Romero R. Amniotic fluid embolism: An evidence-based review. Am J Obstet Gynecol 2009;201:445.e1-13.  |
14. | Benson MD, Kobayashi H, Silver RK, Oi H, Greenberger PA, Terao T. Immunologic studies in presumed amniotic fluid embolism. Obstet Gynecol 2001;97:510-4.  [PUBMED] |
15. | Knight M, Tuffnell D, Brocklehurst P, Spark P, Kurinczuk JJ. Incidence and risk factors for amniotic-fluid embolism. Obstet Gynecol 2010;115:910-7.  |
16. | Haines J, Wilkes RG. Non-fatal amniotic fluid embolism after cervical suture removal. Br J Anaesth 2003;90:244-7.  [PUBMED] |
17. | Weindling AM. The confidential enquiry into maternal and child health (CEMACH). Arch Dis Child 2003;88:1034-7.  [PUBMED] |
18. | Shechtman M, Ziser A, Markovits R, Rozenberg B. Amniotic fluid embolism: Early findings of transesophageal echocardiography. Anesth Analg 1999;89:1456-8.  [PUBMED] |
19. | Stanten RD, Iverson LI, Daugharty TM, Lovett SM, Terry C, Blumenstock E. Amniotic fluid embolism causing catastrophic pulmonary vasoconstriction: Diagnosis by transesophageal echocardiogram and treatment by cardiopulmonary bypass. Obstet Gynecol 2003;102:496-8.  [PUBMED] |
20. | Price TM, Baker VV, Cefalo RC. Amniotic fluid embolism. Three case reports with a review of the literature. Obstet Gynecol Surv 1985; 40:462-75.  [PUBMED] |
21. | Great Britain. Welsh Office. Dept. of Health., Great Britain. Dept. of Health and Social Services Northern Ireland, Great Britain. Scottish Office. Dept. of Health., and Confidential Enquiry into Maternal and Child Health. Why mothers die: Report on confidential enquiries into maternal deaths in the United Kingdom. In, London: H.M.S.O;1998.  |
22. | Gist RS, Stafford IP, Leibowitz AB, Beilin Y. Amniotic fluid embolism. Anesth Analg 2009;108:1599-602.  [PUBMED] |
23. | Lockwood CJ, Bach R, Guha A, Zhou XD, Miller WA, Nemerson Y. Amniotic fluid contains tissue factor, a potent initiator of coagulation. Am J Obstet Gynecol 1991;165:1335-41.  [PUBMED] |
24. | James CF, Feinglass NG, Menke DM, Grinton SF, Papadimos TJ. Massive amniotic fluid embolism: Diagnosis aided by emergency transesophageal echocardiography. Int J Obstet Anesth 2004;13:279-83.  [PUBMED] |
25. | Stafford I, Sheffield J. Amniotic fluid embolism. Obstet Gynecol Clin North Am 2007;34:545-53.  [PUBMED] |
26. | Tuffnell DJ. United kingdom amniotic fluid embolism register. BJOG 2005;112:1625-9.  [PUBMED] |
27. | Levy R, Furman B, Hagay ZJ. Fetal bradycardia and disseminated coagulopathy: Atypical presentation of amniotic fluid emboli. Acta Anaesthesiol Scand 2004;48:1214-5.  [PUBMED] |
28. | Nagarsheth NP, Pinney S, Bassily-Marcus A, Anyanwu A, Friedman L, Beilin Y. Successful placement of a right ventricular assist device for treatment of a presumed amniotic fluid embolism. Anesth Analg 2008;107:962-4.  [PUBMED] |
29. | Yang JI, Kim HS, Chang KH, Ryu HS, Joo HJ. Amniotic fluid embolism with isolated coagulopathy: A case report. J Reprod Med 2006;51:64-6.  [PUBMED] |
30. | Courtney LD. Amniotic fluid embolism. Obstet Gynecol Surv 1974;29:169-77.  [PUBMED] |
31. | Matsuda Y, Kamitomo M. Amniotic fluid embolism: A comparison between patients who survived and those who died. J Int Med Res 2009;37:1515-21.  [PUBMED] |
32. | Rhodes A, Cusack RJ, Newman PJ, Grounds RM, Bennett ED. AR andomised, controlled trial of the pulmonary artery catheter in critically ill patients. Intensive Care Med 2002;28:256-64.  [PUBMED] |
33. | Masson RG, Ruggieri J. Pulmonary microvascular cytology. A new diagnostic application of the pulmonary artery catheter. Chest 1985;88:908-14.  [PUBMED] |
34. | Porat S, Leibowitz D, Milwidsky A, Valsky DV, Yagel S, Anteby EY. Transient intracardiac thrombi in amniotic fluid embolism. BJOG 2004;111:506-10.  [PUBMED] |
35. | Kanayama N, Yamazaki T, Naruse H, Sumimoto K, Horiuchi K, Terao T. Determining zinc coproporphyrin in maternal plasma-a new method for diagnosing amniotic fluid embolism. Clin Chem 1992;38:526-9.  [PUBMED] |
36. | Oi H, Kobayashi H, Hirashima Y, Yamazaki T, Kobayashi T, Terao T. Serological and immunohistochemical diagnosis of amniotic fluid embolism. Semin Thromb Hemost 1998;24:479-84.  [PUBMED] |
37. | Nishio H, Matsui K, Miyazaki T, Tamura A, Iwata M, Suzuki K. A fatal case of amniotic fluid embolism with elevation of serum mast cell tryptase. Forensic Sci Int 2002;126:53-6.  [PUBMED] |
38. | Clark SL, Pavlova Z, Greenspoon J, Horenstein J, Phelan JP. Squamous cells in the maternal pulmonary circulation. Am J Obstet Gynecol 1986;154:104-6.  [PUBMED] |
39. | Lee W, Ginsburg KA, Cotton DB, Kaufman RH. Squamous and trophoblastic cells in the maternal pulmonary circulation identified by invasive hemodynamic monitoring during the peripartum period. Am J Obstet Gynecol 1986;155:999-1001.  [PUBMED] |
40. | Rebarber A, Lonser R, Jackson S, Copel JA, Sipes S. The safety of intraoperative autologous blood collection and autotransfusion during cesarean section. Am J Obstet Gynecol 1998;179:715-20.  [PUBMED] |
41. | Dedhia JD, Mushambi MC. Amniotic fluid embolism. Contin Educ Anaesth Crit Care 2007;7:152-6.  |
42. | Dildy GA, Clark SL. Cardiac arrest during pregnancy. Obstet Gynecol Clin North Am 1995;22:303-14.  [PUBMED] |
43. | Hsieh YY, Chang CC, Li PC, Tsai HD, Tsai CH. Successful application of extracorporeal membrane oxygenation and intra-aortic balloon counterpulsation as lifesaving therapy for a patient with amniotic fluid embolism. Am J Obstet Gynecol 2000;183:496-7.  [PUBMED] |
44. | Leighton BL, Wall MH, Lockhart EM, Phillips LE, Zatta AJ. Use of recombinant factor VIIa in patients with amniotic fluid embolism: A systematic review of case reports. Anesthesiology 2011;115:1201-8.  [PUBMED] |
45. | Kriplani A, Kulshrestha V, Agarwal N, Diwakar S. Role of tranexamic acid in management of dysfunctional uterine bleeding in comparison with medroxyprogesterone acetate. J Obstet Gynaecol 2006;26:673-8.  [PUBMED] |
46. | Peng TC, Kickler TS, Bell WR, Haller E.Obstetric complications in a patient with Bernard-Soulier syndrome. Am J Obstet Gynecol 1991;165:425-6.  [PUBMED] |
47. | Goldszmidt E, Davies S. Two cases of hemorrhage secondary to amniotic fluid embolus managed with uterine artery embolization. Can J Anaesth 2003;50:917-21.  [PUBMED] |
48. | Adolph MD, Frier KA, Stawicki SP, Gerlach AT, Papadimos TJ. Palliative critical care in the intensive care unit: A 2011 perspective. Int J Crit Illn Inj Sci 2011;1:147-53.  [PUBMED] |
49. | Albrechtsen OK. Hemorrhagic disorders following amniotic fluid embolism. Clin Obstet Gynecol 1964;7:361-72.  |
50. | Russell WS, Jones WN. Amniotic fluid embolism - Areview of syndrome with a report of 4 cases. Obstet Gynecol 1965;26:476-85.  [PUBMED] |
51. | Vanderspank-Wright B, Fothergill-Bourbonnais F, Malone-Tucker S, Slivar S. Learning end-of-life care in ICU: Strategies for nurses new to ICU. Dynamics 2011;22:22-5.  [PUBMED] |
52. | Prendergast TJ, Puntillo KA. Withdrawal of life support: Intensive caring at the end of life. JAMA 2002;288:2732-40.  [PUBMED] |
53. | Azoulay E, Pochard F, Kentish-Barnes N, Chevret S, Aboab J, Adrie C, et al. Risk of post-traumatic stress symptoms in family members of intensive care unit patients. Am J Respir Crit Care Med 2005;171:987-94.  [PUBMED] |
54. | Lautrette A, Darmon M, Megarbane B, Joly LM, Chevret S, Adrie C, et al. A communication strategy and brochure for relatives of patients dying in the ICU. N Engl J Med 2007;356:469-78.  [PUBMED] |
55. | McDonagh JR, Elliott TB, Engelberg RA, Treece PD, Shannon SE, Rubenfeld GD, et al. Family satisfaction with family conferences about end-of-life care in the intensive care unit: Increased proportion of family speech is associated with increased satisfaction. Crit Care Med 2004;32:1484-8.  [PUBMED] |
56. | Bennett SM, Litz BT, Lee BS, Maguen S. The scope and impact of perinatal loss: Current status and future directions. Prof Psychol-Res Pr 2005;36:180-7.  |
[Table 1], [Table 2], [Table 3], [Table 4]
This article has been cited by | 1 |
Atypical amniotic fluid embolism successfully treated with a novel protocol: A case report |
|
| Abigail Berry, Andrea Salcedo, Christopher Riba | | Journal of Case Reports and Images in Obstetrics and Gynecology. 2022; 8: 1 | | [Pubmed] | [DOI] | | 2 |
Amniotic fluid embolism syndrome: analysis of the Unites States International Registry |
|
| Irene A. Stafford,Amirhossein Moaddab,Gary A. Dildy,Miranda Klassen,Alexandra Berra,Christine Watters,Michael A. Belfort,Roberto Romero,Steven L. Clark | | American Journal of Obstetrics & Gynecology MFM. 2020; : 100083 | | [Pubmed] | [DOI] | | 3 |
Amniotic fluid embolism: a diagnosis of exclusion in cases of maternal collapse |
|
| Fiona Oglesby,Chris Marsh | | British Journal of Hospital Medicine. 2018; 79(10): C157 | | [Pubmed] | [DOI] | | 4 |
Clinical Presentation and Treatment of Amniotic Fluid Embolism |
|
| Anne-Marie McBride | | AACN Advanced Critical Care. 2018; 29(3): 336 | | [Pubmed] | [DOI] | | 5 |
Atypical Amniotic Fluid Embolism Managed with a Novel Therapeutic Regimen |
|
| Shadi Rezai,Alexander C. Hughes,Tracy B. Larsen,Paul N. Fuller,Cassandra E. Henderson | | Case Reports in Obstetrics and Gynecology. 2017; 2017: 1 | | [Pubmed] | [DOI] | | 6 |
Amniotic fluid embolism |
|
| Kathryn J. Balinger,Melissa T. Chu Lam,Heidi H. Hon,Stanislaw P. Stawicki,James N. Anasti | | Current Opinion in Obstetrics and Gynecology. 2015; 27(6): 398 | | [Pubmed] | [DOI] | | 7 |
Amniotic Fluid Embolism |
|
| Hiroshi Kobayashi | | Obstetrical & Gynecological Survey. 2015; 70(8): 511 | | [Pubmed] | [DOI] | | 8 |
Out-of-Hospital Perimortem Cesarean Section as Resuscitative Hysterotomy in Maternal Posttraumatic Cardiac Arrest |
|
| Francesca Gatti,Marco Spagnoli,Simone Maria Zerbi,Dario Colombo,Mario Landriscina,Fulvio Kette | | Case Reports in Emergency Medicine. 2014; 2014: 1 | | [Pubmed] | [DOI] | | 9 |
Pulmonary Embolic Disorders |
|
| Nicholas I. Batalis,Russell A. Harley | | Academic Forensic Pathology. 2013; 3(4): 420 | | [Pubmed] | [DOI] | |
|
 |
 |
|