Value of fibrinogen in cases of maternal death related to amniotic fluid embolism

Effectiveness, reliability, and validity of new Japanese diagnostic criteria for obstetrical disseminated intravascular coagulation

Since July 2022, obstetrical disseminated intravascular coagulation (DIC) in Japan has been diagnosed based on the new criteria (tentative version), which assesses the main underlying disease, fibrinogen level, and fibrin/fibrinogen degradation products or D-dimer level. In June 2024, the tentative version underwent minor revision and the final version was released. The previous Japanese criteria assessed underlying disease, clinical symptoms, and various laboratory findings. This study aimed to prove the effectiveness, reliability, and validity of the new criteria (final version). We analyzed 212 women with singleton pregnancies who delivered after 22 gestational weeks and experienced blood loss ≥ 1000 mL during vaginal delivery or ≥ 2000 mL during cesarean section. Those with missing laboratory findings before receiving blood transfusion at delivery were excluded. In the obstetrical DIC group, the frequency of fibrinogen levels < 150 mg/dL was significantly higher than in the control group (90% vs. 5%, p < 0.0001), as was the frequency of scores ≥ 8 according to the previous Japanese criteria (100% vs. 10%, p < 0.0001). Cronbach alpha was 0.757 and Spearman's rank-order correlation was 0.558 between the new and previous criteria. In conclusion, we proved the effectiveness, reliability, and validity of the Japanese new criteria (final version) to diagnose obstetrical DIC.

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

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

Comparative analysis of hyperfibrinolysis with activated coagulation between amniotic fluid embolism and severe placental abruption

Amniotic fluid embolism (AFE) and placental abruption (PA) are typical obstetric diseases associated with disseminated intravascular coagulation (DIC). AFE is more likely to be complicated with enhanced fibrinolysis than PA. AFE may have an additional mechanism activating fibrinolytic cascade. We aimed to compare the coagulation/fibrinolysis factors among AFE, PA, and peripartum controls. We assessed AFE cases registered in the Japanese AFE Registry, and PA cases complicated with DIC (severe PA) and peripartum controls recruited at our hospital. The following factors in plasma were compared: prothrombin fragment 1 + 2 (PF1 + 2), plasmin α2-plasmin inhibitor complex (PIC), tissue factor (TF), tissue plasminogen activator (tPA), annexin A2 (AnnA2), total thrombin activatable fibrinolysis inhibitor (TAFI) including its activated form (TAFIa), and plasminogen activator inhibitor-type 1 (PAI-1). PF1 + 2 and PIC were markedly increased in both AFE (n = 27) and severe PA (n = 12) compared to controls (n = 23), without significant difference between those disease groups; however, PIC in AFE showed a tendency to elevate relative to PF1 + 2, compared with severe PA. AFE had significantly increased tPA and decreased total TAFI levels compared with severe PA and controls, which might be associated with further plasmin production in AFE and underlie its specific fibrinolytic activation pathway.

High maternal mortality rate associated with advanced maternal age in Japan

This study aimed to clarify the relationship between maternal mortality and advanced maternal age in Japan and to provide useful information for future perinatal management. Maternal death rates by age group were investigated for all maternal deaths in Japan for an 11-year period, from 2010 to 2021. Maternal deaths among those aged ≥ 40 years were examined in detail to determine the cause, and the number of deaths by cause was calculated. The causes of onset of the most common causes of death were also investigated. The maternal mortality rates were 0.8 (95% confidence interval [CI] 0.3-4.7) for < 20 years, 2.6 (95% CI 1.7-3.8) for 20-24 years, 2.9 (95% CI 2.3-3.6) for 25-29 years, 3.9 (95% CI 3.3-4.5) for 30-34 years, 6.8 (95% CI 5.9-7.9) for 35-39 years, and 11.2 (95% CI 8.8-14.3) for ≥ 40 years of age. Patients who were ≥ 40 years of age had a significantly higher mortality rate compared to that in other age groups. Hemorrhagic stroke was the most common cause of death in patients aged ≥ 40 years (15/65 [23%]), and preeclampsia (8/15 [54%]) was the most common cause of hemorrhagic stroke. Maternal mortality is significantly higher in older than in younger pregnant women in Japan, with hemorrhagic stroke being the most common cause of maternal death among women > 40 years of age. More than half of hemorrhagic strokes are associated with hypertension disorder of pregnancy. These facts should be considered by women who become pregnant at an advanced age and by healthcare providers involved in their perinatal care.

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

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

Consumptive Coagulopathy Involving Amniotic Fluid Embolism: The Importance of Earlier Assessments for Interventions in Critical Care

Supplemental Digital Content is available in the text.

Objectives:

Amniotic fluid embolism is a rare disease that induces fatal coagulopathy; however, due to its rarity, it has not yet been examined in detail. The strict diagnostic criteria by Clark for amniotic fluid embolism include severe coagulopathy complicated by cardiopulmonary insufficiency, whereas the Japanese criteria also include postpartum hemorrhage or Disseminated Intravascular Coagulation in clinical practice. Amniotic fluid embolism cases with preceding consumptive coagulopathy may exist and are potential clinical targets for earlier assessments and interventions among amniotic fluid embolism cases fulfilling the Japanese, but not Clark criteria. The present study was performed to compare coagulopathy in the earlier stage between the amniotic fluid embolism patients diagnosed by Clark criteria (Clark group, n = 6), those by the Japanese criteria (Non-Clark group, n = 10), and peripartum controls and identify optimal clinical markers for earlier assessments of amniotic fluid embolism-related consumptive coagulopathy.

Design:

Retrospective case-control study.

Setting:

A single university-based center. Our amniotic fluid embolism registry program has accumulated clinical information and blood samples since 2003.

Patients:

Amniotic fluid embolism patients in the Clark and Non-Clark groups between 2009 and 2017 and peripartum controls.

Interventions:

None.

Measurements and Main Results:

Clinical information was collected on hemoglobin levels, platelet counts, and coagulation- and fibrinolysis-related variables. Fibrinolytic parameters were also measured and compared among the three groups before blood transfusion. Fibrinogen levels in all patients in the Clark group and most in the Non-Clark group decreased earlier than hemoglobin levels, which was consistent with the high hemoglobin/fibrinogen ratio and, thus, is a promising clinical marker for the earlier assessment of amniotic fluid embolism-related consumptive coagulopathy.

Conclusions:

Earlier evaluations of consumptive coagulopathy and hyperfibrinolysis using the hemoglobin/fibrinogen ratio following preemptive treatment may reduce the occurrence or prevent the aggravation of severe coagulopathy in amniotic fluid embolism patients.

Fibrinogen may aid in the early differentiation between amniotic fluid embolism and postpartum haemorrhage: a retrospective chart review

This study aimed to determine whether blood loss and fibrinogen can differentiate amniotic fluid embolism (AFE) from postpartum haemorrhage (PPH). This retrospective case–control study included nine patients with clinical AFE (“AFE group”) and 78 patients with PPH managed at our tertiary care perinatal centre between January 2014 and March 2016. Patients meeting the Japanese diagnostic criteria for AFE were stratified into cardiopulmonary collapse-type AFE and disseminated intravascular coagulation (DIC)-type AFE groups. The relationship between blood loss and fibrinogen at onset was examined to compare DIC severity. Vital signs at onset were not significantly different. The AFE group had significantly less blood loss at onset (1506 mL vs 1843 mL, P = 0.0163), significantly more blood loss 2 h post-onset (3304 mL vs 1996 mL, P < 0.0001) and more severe coagulopathy and fibrinolysis. The blood loss/fibrinogen (B/F) ratio at onset was significantly higher in the DIC-type AFE group (23.15 ± 8.07 vs 6.28 ± 3.35 mL dL/mg, P < 0.0001). AFE was complicated by catastrophic DIC irrespective of blood loss at onset. Fibrinogen exhibited the strongest correlation among test findings at onset. The B/F ratio may help differentiate PPH from DIC-type AFE and diagnose clinical AFE, facilitating optimal replacement of coagulation factors during the early stages.

Perinatal outcome in case of maternal death for cerebrovascular acute disorders: a nationwide study in Japan

OBJECTIVE

The goal of this study is to find clues to improve perinatal outcomes in the case of cerebrovascular acute disorders during pregnancy.

STUDY DESIGN

We analyzed 35 cases of cerebrovascular diseases related to maternal deaths in Japan those that occurred during pregnancy and reported to the Committee of the Ministry of Health, Labor, and Welfare from 2010 to 2018.

RESULTS

Cerebrovascular acute disorders occurred at 34.6 ± 6.6 gestational weeks. There were seven intrauterine fetal deaths (IUFD), and eight cases showed neonatal asphyxia with umbilical arterial pH between 6.7 and 7.0 (asphyxia cases, n = 15). In two of eight newborns, brain hypothermia therapy was given, and all survived without neurological sequelae. Maternal dyspnea was significantly related to severe prolonged decelerations of the fetus (p < .05), and asphyxia cases (p < .005). Median time from maternal onset to delivery (OD time) was significantly longer in asphyxia cases than in the non-asphyxia cases (84 vs 29 min, p < .05). OD time over 30 min was significantly related to the antepartum occurrence, cervical dilatation <5 cm (p < .05), onset outside of the hospital (p < .001), and maternal transfer before delivery (p < .001).

CONCLUSION

More than 40% of cases experienced fetal asphyxia, and 20% ended in IUFD in maternal deaths related to cerebrovascular acute disorders. Maternal respiratory support and rapid delivery would be the keys to improve perinatal outcomes in case of cerebrovascular acute disorders during pregnancy.

Analysis of preventability of hypertensive disorder in pregnancy-related maternal death using the nationwide registration system of maternal deaths in Japan

Objective: Hypertensive disorder of pregnancy (HDP) is a major cause of maternal death. The goal of this study was to investigate factors associated with maternal death due to HDP. Study design: HDP-related maternal deaths in Japan reported to the Committee of the Ministry of Health, Labor and Welfare from 2010 to 2015 were examined. Results: Out of 47 cases of HDP, 30 were identified as the major cause of maternal death. The median maternal age was 34 years (range 24-45) and the mortality in women aged ≥40 years was seven times higher that than in women aged <34 years. The etiologies were intracerebral hemorrhage (n = 22), subarachnoid hemorrhage (n = 3), subcapsular hematoma of the liver (n = 2), peripartum cardiomyopathy (n = 2), and eclampsia (n = 1), and 19 cases were deemed preventable. The most frequent antepartum problems were delays in hospitalization, maternal transfer, and termination of pregnancy. In four cases, diagnosis of HELLP syndrome was too late because laboratory data were not checked, despite the patient reporting epigastric pain or showing elevation of blood pressure (BP). Treatment for lowering of BP was improper in 2/3 intrapartum cases, even though BP was elevated during pregnancy (144 versus 188 mmHg, p < .001). There was inadequate lowering of BP and lack of use of magnesium sulfate in 7/11 postpartum cases (64%), despite aspartate aminotransferase (AST) (p < .005), alanine aminotransferase (ALT) (p < .01), lactate dehydrogenase (LDH) (p < .005), and platelet count (PLT) (p < .01) all significantly worsening after delivery. Conclusion: HDP accounts for 11% of maternal deaths in Japan. Mothers aged ≥40 years are most at risk for HDP-related maternal death. Major concerns for preventabilities were late hospitalization, maternal transportation, and termination of pregnancy for term or near-term HDP. Regular vital checks and prompt lowering of BP were lacked during labor in most cases. HELLP syndrome should be managed at a general hospital with sufficient medical resources.

Analysis of preventability of stroke-related maternal death from the nationwide registration system of maternal deaths in Japan

OBJECTIVE

The number of stroke-related maternal deaths is increasing in Japan. We investigated methods to reduce maternal death from stroke.

METHODS

We analyzed stroke-related maternal deaths in Japan reported to the Committee of the Ministry of Health, Labor, and Welfare from 2010 to 2014 inclusive.

RESULTS

A total of 35 cases were identified. The median maternal age was 35 years (range 22-45) and the incidence of stoke in women ≥40 was seven-fold higher than in <34. Etiologies were pregnancy induced hypertension in 16, subarachnoid hemorrhage in seven, cerebral infarction in three, arteriovenous malformation in two, Moyamoya disease in one, and origin unknown cerebral hemorrhage in six. These cases occurred in antepartum 43%, in postpartum 31%, and in intrapartum 26%. 23 cases were deemed non-preventable and 12 cases preventable. Possible preventable factors occurred antepartum in 23, postpartum in seven, and intrapartum in six. Preventable features included inadequate hypertension control (33%), presenting too late for termination of pregnancy (14%), delayed hospitalization (11%), and delayed maternal transfer (11%).

CONCLUSIONS

A total of 90% of strokes were hemorrhagic, and older mothers (≥ 40) were most at risk. Most possible preventable factors occurred antepartum, and improved control of hypertension and earlier termination would help to reduce maternal death from stroke.