Amniotic fluid embolism: antepartum, intrapartum and demographic factors

Amniotic fluid pulmonary embolism and COVID-19: Case report

Amniotic fluid embolism is a rare complication of peripartum. It is caused by the entry of fetal components into the maternal systemic circulation. There are 2 main types: typical; it presents with the triad of hemodynamic collapse, respiratory distress and disseminated intravascular coagulation type coagulopathy, while atypical; disseminated intravascular coagulation does not occur. SARS CoV-2 infection causes coagulopathy due to the alteration of Virchow's triad and coagulation factors. We present the case of a 21-year-old pregnant woman who consulted for premature rupture of membranes, with an indication for cesarean section, and during surgery presented bradycardia, hypotension, and desaturation until cardiorespiratory arrest. An angiotomography showed amniotic fluid embolism associated with pulmonary edema, ruling out differential diagnoses associated with the disease, leaving as the only cause of the infection confirmed by COVID-19, which, it was inferred, was closely related to the immunological disorder suffered by the patient.

Post-abortion Complications: A Narrative Review for Emergency Clinicians

An abortion is a procedure defined by termination of pregnancy, most commonly performed in the first or second trimester. There are several means of classification, but the most important includes whether the abortion was maternally “safe” (performed in a safe, clean environment with experienced providers and no legal restrictions) or “unsafe” (performed with hazardous materials and techniques, by person without the needed skills, or in an environment where minimal medical standards are not met). Complication rates depend on the procedure type, gestational age, patient comorbidities, clinician experience, and most importantly, whether the abortion is safe or unsafe. Safe abortions have significantly lower complication rates compared to unsafe abortions. Complications include bleeding, retained products of conception, retained cervical dilator, uterine perforation, amniotic fluid embolism, misoprostol toxicity, and endometritis. Mortality rates for safe abortions are less than 0.2%, compared to unsafe abortion rates that range between 4.7-13.2%. History and physical examination are integral components in recognizing complications of safe and unsafe abortions, with management dependent upon the diagnosis. This narrative review provides a focused overview of post-abortion complications for emergency clinicians.

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.

Maternal death analysis based on data from the nationwide registration system in Japan (2010-2018)

The maternal mortality rate in Japan was 3.5 per 100 000 live births in 2017, similar to that reported in other developed countries. To reduce the number of maternal deaths, a Japanese nationwide registration and analysis system was implemented in 2010. Between January 2010 and April 2018, 367 maternal deaths were reported. Among them, by reviewing 80 autopsy records, the direct obstetric causes of death were identified in 52 women. The major causes of deaths were amniotic fluid embolism and acute pulmonary thromboembolism. The other 26 maternal deaths were associated with indirect obstetric causes including invasive Group A Streptococcus infection, aortic dissection, cerebral stroke and cardiomyopathies. This review highlights the importance of autopsy in maternal deaths. On analyzing 42 autopsy specimens obtained from registered cases of maternal death during 2012-2015, the 36% of causes of death by autopsy were discordant with the clinical diagnosis. Moreover, of the 38% of non-autopsied maternal death, the cause of death could not be clarified from the clinical chart. We emphasized that detailed autopsies are necessary to clarify the precise pathologic evidence related to pregnancy and delivery, especially causes of unexpected death such as amniotic fluid embolism.

Technical note: double immunohistochemical stain (anti-CD31 and anti-cytokeratins) as a tool for a confident forensic post-mortem diagnosis of amniotic fluid embolism

Amniotic fluid embolism (AFE) is a rare cause of unexpected late maternal gestational death. The forensic post-mortem diagnosis is rendered upon the histological recognition of fetal "foreign" material inside maternal lung vasculature. The authors propose a double immunohistochemical (anti-CD31 plus anti-cytokeratin AE1/AE3) stain in order to assess accurate amniotic fluid pulmonary embolic burden in a highly reproducible fashion based on the fact that such technique allows to detect an impressive amount of scales within lung vasculature, thereby offering further evidence that pulmonary embolic obstructive microangiopathy, rather than anaphylactoid reaction, is major determinant in AFE-related death.

Amniotic fluid embolism syndrome: analysis of the Unites States International Registry

BACKGROUND

Incidence, risk factors, and perinatal morbidity and mortality rates related to amniotic fluid embolism remain a challenge to evaluate, given the presence of differing international diagnostic criteria, the lack of a gold standard diagnostic test, and a significant overlap with other causes of obstetric morbidity and mortality.

OBJECTIVE

The aims of this study were (1) to analyze the clinical features and outcomes of women using the largest United States-based contemporary international amniotic fluid embolism registry, and (2) to investigate differences in demographic and obstetric variables, clinical presentation, and outcomes between women with typical versus atypical amniotic fluid embolism, using previously published and validated criteria for the research reporting of amniotic fluid embolism.

MATERIALS AND METHODS

The AFE Registry is an international database established at Baylor College of Medicine (Houston, TX) in partnership with the Amniotic Fluid Embolism Foundation (Vista, CA) and the Perinatology Research Branch of the Division of Intramural Research of the NICHD/NIH/DHHS (Detroit, MI). Charts submitted to the registry between August 2013 and September 2017 were reviewed, and cases were categorized into typical, atypical, non-amniotic fluid embolism, and indeterminate, using the previously published and validated criteria for the research reporting of AFE. Demographic and clinical variables, as well as outcomes for patients with typical and atypical AFE, were recorded and compared. Student t tests, χ2 tests, and analysis of variance tables were used to compare the groups, as appropriate, using SAS/STAT software, version 9.4.

RESULTS

A total of 129 charts were available for review. Of these, 46% (59/129) represented typical amniotic fluid embolism and 12% (15/129) atypical amniotic fluid embolism, 21% (27/129) were non-amniotic fluid embolism cases with a clear alternative diagnosis, and 22% (28/129) had an uncertain diagnosis. Of the 27 women misclassified as an amniotic fluid embolism with an alternative diagnosis, the most common actual diagnosis was hypovolemic shock secondary to postpartum hemorrhage. Ten percent (6/59) of the women with typical amniotic fluid embolism had a pregnancy complicated by placenta previa, and 8% (5/61) had undergone in vitro fertilization to achieve pregnancy. In all, 66% (49/74) of the women with amniotic fluid embolism reported a history of atopy or latex, medication, or food allergy, compared to 34% of the obstetric population delivered at our hospital over the study period (P < .05).

CONCLUSION

Our data represent a series of women with amniotic fluid embolism whose diagnosis has been validated by detailed chart review, using recently published and validated criteria for research reporting of amniotic fluid embolism. Although no definitive risk factors were identified, a high rate of placenta previa, reported allergy, and conceptions achieved through in vitro fertilization was observed.

The Effect of Labor Epidural Analgesia on Breastfeeding Outcomes: A Prospective Observational Cohort Study in a Mixed-Parity Cohort

BACKGROUND

The effect of labor epidural analgesia (LEA) on successful breastfeeding has been evaluated in several studies with divergent results. We hypothesized that LEA would not influence breastfeeding status 6 weeks postpartum in women who intended to breastfeed in an environment that encourages breastfeeding.

METHODS

In this prospective observational cohort study, a total of 1204 women intending to breastfeed, delivering vaginally with or without LEA, were included; breastfeeding was recorded at 3 days and 6 weeks postpartum. Primary outcome was breastfeeding at 6 weeks, and the χ test was used for comparisons between women delivering with and without LEA, according to parity status and previous breastfeeding experience. Total epidural fentanyl dose and oxytocin use (yes/no) were recorded. A multivariable logistic regression was performed to assess factors affecting breastfeeding at 6 weeks.

RESULTS

The overall breastfeeding rate at 6 weeks was 76.9%; it was significantly lower among women delivering with LEA (74.0%) compared with women delivering without LEA (83.4%; P < .001). Among 398 nulliparous women, 84.9% delivered with LEA, compared with 61.8% of multiparous women (P < .001). Multiparous women (N = 806) were more likely to breastfeed at 6 weeks (80.0% vs 70.6% nullipara; P < .001). Using multivariable logistic regression that accounted for 14 covariates including parity, and an interaction term between parity and LEA use, LEA was significantly associated with reduced breastfeeding at 6 weeks (odds ratio, 0.60; 95% confidence interval, 0.40-0.90; P = .015). In a modified multivariable logistic regression where parity was replaced with previous breastfeeding experience, both as a covariate and in the interaction term, only previous breastfeeding experience was associated with increased breastfeeding at 6 weeks (odds ratio, 3.17; 95% confidence interval, 1.72-5.80; P < .001).

CONCLUSIONS

In our mixed-parity cohort, delivering with LEA was associated with reduced likelihood of breastfeeding at 6 weeks. However, integrating women's previous breastfeeding experience, the breastfeeding rate was not different between women delivering with and without LEA among the subset of multiparous women with previous breastfeeding experience. Therefore, our findings suggest that offering lactation support to the subset of women with no previous breastfeeding experience may be a simple approach to improve breastfeeding success. This concept subscribes to the notion that women at risk for an undesired outcome be offered tailored interventions with a personalized approach.

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.

Breastfeeding and its outcome in Women Receiving Epidural Analgesia for Childbirth

Background:

Breastfeeding is an important issue in postpartum period and critical to the infant's health, but childbirth interventions such as childbirth analgesia may affect the onset and duration of the process. This study aimed to determine the status of breastfeeding in women receiving epidural analgesia.

Materials and Methods:

This cohort study was conducted on 393 mothers in the postpartum period that had vaginal delivery with or without using epidural analgesia (with their own choice) between December 2017 and September 2018. After selecting the convenient samples, the researcher-made outcome breastfeeding checklists were completed in selected hospitals in Isfahan, Iran, Within 24 hours and 4 weeks after delivery. Data were analyzed using statistical methods (Independent t test, Mann-Whitney, ANCOVA, and Chi-square). The significance level of the tests was less than 0.05.

Results:

According to the results, most of the subjects in the two groups began breastfeeding during the first hour after childbirth. There was no significant difference between the two groups in the beginning of breastfeeding while controlling the number of labors. There was no significant difference between the two groups in comparison to the type of milk given to the infant Within 24 hours after birth and 4 weeks after birth, either. There was no significant difference between the two groups in comparison to breastfeeding problems at either time.

Conclusions:

According to the results, saying that there is no negative effect by epidural analgesia on the breastfeeding process, using this analgesia is recommended to promote natural childbirth.

Amniotic fluid embolism mortality rate

AIM

The objective of this study was to determine the mortality rate of amniotic fluid embolism (AFE) using population-based studies and case series.

METHODS

A literature search was conducted using the two key words: 'amniotic fluid embolism (AFE)' AND 'mortality rate'. Thirteen population-based studies were evaluated, as well as 36 case series including at least two patients.

RESULTS

The mortality rate from population-based studies varied from 11% to 44%. When nine population-based studies with over 17 000 000 live births were aggregated, the maternal mortality rate was 20.4%. In contrast, the mortality rate of AFE in case series varies from 0% to 100% with numerous rates in between.

CONCLUSION

The AFE mortality rate in population-based studies varied from 11% to 44% with the best available evidence supporting an overall mortality rate of 20.4%. Data from case series should no longer be used as a basis for describing the lethality of AFE.

Maternal, Labor, Delivery, and Perinatal Outcomes Associated with Placental Abruption: A Systematic Review

Objective Risk factors for placental abruption have changed, but there has not been an updated systematic review investigating outcomes. Methods We searched PubMed, EMBASE, Web of Science, SCOPUS, and CINAHL for publications from January 1, 2005 through December 31, 2016. We reviewed English-language publications reporting estimated incidence and/or risk factors for maternal, labor, delivery, and perinatal outcomes associated with abruption. We excluded case studies, conference abstracts, and studies that lacked a referent/comparison group or did not clearly characterize placental abruption. Results A total of 123 studies were included. Abruption was associated with elevated risk of cesarean delivery, postpartum hemorrhage and transfusion, preterm birth, intrauterine growth restriction or low birth weight, perinatal mortality, and cerebral palsy. Additional maternal outcomes included relaparotomy, hysterectomy, sepsis, amniotic fluid embolism, venous thromboembolism, acute kidney injury, and maternal intensive care unit admission. Additional perinatal outcomes included acidosis, encephalopathy, severe respiratory disorders, necrotizing enterocolitis, acute kidney injury, need for resuscitation, chronic lung disease, infant death, and epilepsy. Conclusion Few studies examined outcomes beyond the initial birth period, but there is evidence that both mother and child are at risk of additional adverse outcomes. There was also considerable variation in, or absence of, the reporting of abruption definitions.