Non-haemorrhagic obstetric shock

Echocardiography findings in amniotic fluid embolism: a systematic review of the literature

PURPOSE

Amniotic fluid embolism (AFE) is a leading cause of obstetrical cardiac arrest and maternal morbidity. The pathogenesis of hemodynamic collapse is thought to be from right ventricular (RV) failure; however, there is a paucity of data documenting echocardiography findings in this population. We undertook a systematic review of the literature to evaluate the echocardiography findings in patients with AFE.

SOURCES

We retrieved all case reports and case series reporting AFE in Embase and MEDLINE from inception to 20 November 2021. Studies reporting AFE diagnosed by fulfilling at least one of three different proposed AFE criteria and echocardiography findings during hospitalization were included. Patient and echocardiographic data were retrieved, and univariate logistic regression analysis was performed for outcomes of interest. Bias was assessed using the Joanna Briggs Institute clinical appraisal tool for case series.

PRINCIPAL FINDINGS

Eighty publications reporting on 84 patients were included in the final review. Fifty-five out of 82 patients with data (67%) showed RV dysfunction, including 11/82 (13%) with biventricular dysfunction; 14/82 (17%) had normal systolic function. No data on RV or left ventricular function were reported for two patients. The presence of RV dysfunction on echocardiography was associated with cardiac arrest (odds ratio [OR], 3.66; 95% confidence interval [CI], 1.39 to 9.67; P = 0.009), and a composite risk of cardiac arrest, maternal death or use of extracorporeal membrane oxygenation (OR, 3.86; 95% CI, 1.43 to 10.4; P = 0.007). A low risk of bias was observed in 15/84 (18%) cases.

CONCLUSIONS

Right ventricular dysfunction on echocardiography is a common finding in AFE and is associated with a high risk of cardiac arrest. The finding of RV dysfunction on echocardiography may help diagnose AFE and help triage the highest risk patients with AFE.

STUDY REGISTRATION

PROSPERO (CRD42021271323); registered 1 September 2021.

Successful resuscitation by using extracorporeal membrane oxygenation in a patient with amniotic fluid embolism: a case report

Amniotic fluid embolism (AFE) is a rare disease, but it is a potentially fatal condition, as well as a leading cause of unpredictable maternal death in developed countries. The typical clinical symptoms of AFE include hypoxia, hypotension, and coagulopathy, and with rapid progression, it may cause cardiac arrest and death. We report a case of sudden hemodynamic instability due to amniotic fluid embolism, which was successfully treated with veno-arterial extracorporeal membrane oxygenation (ECMO). A 39-year-old woman was scheduled for delivery at 38 weeks and 2 days of gestation. During labor, sudden generalized tonic-clonic seizures developed, followed by dyspnea and cyanosis. Despite immediate cesarean section being performed, she became hypoxemic and experienced cardiovascular collapse. ECMO was promptly applied, and the patient became stable 8 days after cesarean section. ECMO appears to be an appropriate treatment option for catastrophic amniotic fluid embolism.

Impact of fetal maceration grade on risk of maternal disseminated intravascular coagulation after intrauterine fetal death - A retrospective cohort study

Disseminated intravascular coagulation (DIC) is a life-threatening event that is the endpoint of a pathologically activated cascade leading to excessive consumption of platelets culminating in bleeding. Several diseases are known to be associated with DIC, some of which may also occur during pregnancy or the puerperium. One of the potential risk factors that have been considered as a potential trigger for DIC is the retention of a highly macerated fetus after intrauterine fetal death (IUFD). However, sparse evidence exists on its clinical implication on hemostasis parameters. In this retrospective single-center study, we investigated the role of fetal maceration grades 0-III on the risk of DIC in 91 women following IUFD between gestational weeks (+days) 22 + 0 and 41 + 6 between 2003 and 2017. We calculated the Erez DIC-score after consideration of maternal platelet count (PC), prothrombin time (PT) and fibrinogen (Fib) and correlated the findings with fetal maceration grade. Mean (±SD) age of women was 32.1 ± 6.7 years. Neither maternal hemostasis parameters (PC, PT, Fib), nor the Erez score showed a statistically significant difference between maceration grades 0-III with median values of 1 for all four grades (maceration grade I: range 0 to 27; I: 0 to 51; II: 0 to 52; III: 0 to 39). We therefore conclude, that the pathophysiology of DIC in women after singleton IUFD is unrelated to the degree of fetal maceration.

The Importance of the Monitoring of Resuscitation with Blood Transfusion for Uterine Inversion in Obstetrical Hemorrhage

Objective. The aim of this study was to describe critical care for obstetrical hemorrhage, especially in cases of uterine inversion. Study Design. We extracted data for six patients diagnosed with uterine inversion concerning resuscitation. Results. The shock index on admission of the six patients was 1.6 or more on admission. Four of the six experienced delay in diagnosis and received inadequate fluid replacement. Five of the six experienced delay in transfer. Five of the six underwent simultaneous blood transfusion on admission, and the remaining patient experienced a delay of 30 minutes. All six patients successfully underwent uterine replacement soon after admission. One maternal death occurred due to inappropriate practices that included delay in diagnosis, delay in transfer, inadequate fluid replacement, and delayed transfusion. Two patients experiencing inappropriate practices involving delay in diagnosis, delay in transfer, and inadequate fluid replacement survived. Conclusion. If a delay in diagnosis occurs simultaneously with a delay in transfer and inadequate fluid replacement, failure in providing a prompt blood transfusion may be critical and result in maternal death. The monitoring of resuscitation with blood transfusion for uterine inversion is essential for the improvement of obstetrical care.

Amniotic fluid embolism pathophysiology suggests the new diagnostic armamentarium: β-tryptase and complement fractions C3-C4 are the indispensable working tools

Amniotic fluid embolism (AFE) is an uncommon obstetric condition involving pregnant women during labor or in the initial stages after delivery. Its incidence is estimated to be around 5.5 cases per 100,000 deliveries. Therefore, this paper investigated the pathophysiological mechanism, which underlies AFE, in order to evaluate the role of immune response in the development of this still enigmatic clinical entity. The following databases (from 1956 to September 2014) Medline, Cochrane Central, Scopus, Web of Science and Science Direct were used, searching the following key words: AFE, pathophysiology, immune/inflammatory response, complement and anaphylaxis. The main key word “AFE” was searched singularly and associated individually to each of the other keywords. Of the 146 sources found, only 19 were considered appropriate for the purpose of this paper. The clinical course is characterized by a rapid onset of symptoms, which include: acute hypotension and/or cardiac arrest, acute hypoxia (with dyspnoea, cyanosis and/or respiratory arrest), coagulopathies (disseminated intravascular coagulation and/or severe hemorrhage), coma and seizures. The pathology still determines a significant morbidity and mortality and potential permanent neurological sequelae for surviving patients. At this moment, numerous aspects involving the pathophysiology and clinical development are still not understood and several hypotheses have been formulated, in particular the possible role of anaphylaxis and complement. Moreover, the detection of serum tryptase and complement components and the evaluation of fetal antigens can explain several aspects of immune response.

Uterine Balloon Tamponade Device and Cervical Cerclage to Correct Partial Uterine Inversion during Puerperium; Case Report

A healthy 26-year-old woman was noted to have residual uterine inversion after manual replacement of puerperal uterine inversion under general anaesthesia. This was corrected by the insertion of a balloon tamponade device. A cervical suture was applied to prevent ballooning of the device through the cervix. This little modification was immediately successful in preventing ballooning of the tamponade device. The whole idea was to overcome the need for a laparotomy. A review of the literature and the mechanism of action are discussed here.

Evidence of maternal platelet activation, excessive thrombin generation, and high amniotic fluid tissue factor immunoreactivity and functional activity in patients with fetal death

OBJECTIVE

Fetal death can lead to disseminated intravascular coagulation or fetal death syndrome. However, currently it is not clear what are the changes in the coagulation system in patients with a fetal death without the fetal death syndrome. This study was undertaken to determine: (1) whether fetal death in the absence of fetal death syndrome is associated with changes in hemostatic markers in maternal plasma and amniotic fluid; and (2) whether maternal hypertension or placental abruption are associated with further changes in the hemostatic profile of these patients.

METHODS

A cross-sectional study included the following: (1) determination of changes in markers of coagulation and platelet activation in patients with a normal pregnancy (n = 71) and patients with fetal demise (FD) without disseminated intravascular coagulation (n = 65); (2) determination of the amniotic fluid (AF)-tissue factor concentration and activity, as well as the concentrations of thrombin-antithrombin III (TAT) complexes in patients with a normal pregnancy (n = 25) and those with a FD (n = 36) who underwent amniocentesis. Plasma and AF concentrations of TAT complexes and TF (an index of thrombin generation), as well as maternal plasma concentrations of sCD40L (a marker of platelet activation), tissue factor pathway inhibitor (TFPI) and prothrombin fragments (PF) 1 + 2 (also an indicator of in vivo thrombin generation) were measured by ELISA. TF and TFPI activity were measured using chromogenic assays.

RESULTS

(1) patients with FD without hypertension had a higher median maternal plasma sCD40L concentration than normal pregnant women (P < 0.001); (2) patients with FD had a higher median maternal plasma TAT III complexes than women with a normal pregnancy (P < 0.001); (3) the median AF-TF concentration and activity were higher in the FD group than in the normal pregnancy group (P < 0.001 for both); (4) patients with preeclampsia and FD had a higher median maternal plasma immunoreactive TF concentration than both normotensive patients with FD and women with normal pregnancies (P < 0.001 and P = 0.001, respectively); (5) the median plasma TF activity was higher in patients with preeclampsia and FD than that of women with normal pregnancies (P = 0.003); (6) among patients with a FD, those with placental abruption had a higher median AF-TAT complexes concentration than those without abruption (P = 0.0004).

CONCLUSIONS

Our findings indicate that: (1) mothers with a FD have evidence of increased in vivo thrombin generation and platelet activation than women with normal pregnancies; (2) patients with a FD and hypertension had a higher degree of TF activation than those with fetal death but without hypertension; (3) the AF of women with a FD had a higher median TF concentration and activity than that of normal pregnant women. AF can be a potential source for tissue factor and it participates in the development of fetal death syndrome in patients with a retained dead fetus.

Amniotic fluid embolism: an evidence-based review

We conducted an evidence-based review of information about [corrected] amniotic fluid embolism (AFE). The estimated incidence of AFE is 1:15,200 and 1:53,800 deliveries in North America and Europe, respectively. The case fatality rate and perinatal mortality associated with AFE are 13-30% and 9-44%, respectively. Risk factors associated with an [corrected] increased risk of AFE include advanced maternal age, placental abnormalities, operative deliveries, eclampsia, polyhydramnios, cervical lacerations, [corrected] and uterine rupture. The hemodynamic response in [corrected] AFE is biphasic, with initial pulmonary hypertension and right ventricular failure, followed by left ventricular failure. Promising therapies include selective pulmonary vasodilators and recombinant activated factor VIIa. Important topics for future research are presented.

Nonhemorrhagic primary obstetric shock

OBJECTIVE

Clinical evaluation of nonhemorrhagic primary obstetric shock (NHPOS).

METHODS

In a retrospective clinical study, data on 8 cases of NHPOS were analyzed. Data on patient age, parity, week of gestation, comorbidity, possible etiologic trigger, course of disease with clinical picture and laboratory findings of coagulopathy, and patient outcome including autopsy findings in two lethal outcomes were analyzed.

RESULTS

These 8 patients were treated in the intensive care unit. One patient died during delivery from cardiopulmonary arrest in the state of irreversible obstetric shock, verified by massive pulmonary thromboembolism at autopsy. Another patient died from stroke and cerebral coma caused by trophoblastic cerebrovascular embolism 5 days after artificial abortion, showing a clinical picture of shock and cardiopulmonary arrest. In 1 patient, severe septic shock developed several hours after premature stillbirth and abruptio placentae in the 26th week of pregnancy, associated with disseminated intravascular coagulopathy. Four patients developed intrapartum NHPOS, with a clinical picture of chest pain, dyspnea, tachycardia, hypotension, cyanosis, and disseminated intravascular coagulopathy, as demonstrated by laboratory findings. Based on clinical picture and laboratory findings, amniotic fluid embolism or trophoblastic embolism was suspected. All these patients survived. One patient developed NHPOS during the third labor stage after vacuum extraction because of a macrosomic child, followed by disseminated intravascular coagulopathy and secondary hemorrhage which necessitated B-Lynch procedures and total hysterectomy for massive bleeding. Hereditary thrombophilia was detected in subsequent patients.

CONCLUSIONS

NHPOS can be caused by amniotic fluid embolism, trophoblastic embolism or thromboembolism, and sepsis. These conditions may frequently prove fatal due to their abrupt and unexpected course, mostly during pregnancy, delivery, or immediately thereafter.

Prevention and management of venous thromboembolism in pregnancy

Pulmonary thromboembolism is a major cause of maternal mortality. DVT causes significant morbidity in pregnancy and in later life owing to the post-thrombotic syndrome. Obstetricians must have an understanding of the risk factors for VTE, the appropriate use of prophylaxis, the need for objective diagnosis in women with suspected VTE, and the appropriate use of anticoagulant therapy. Greater use of prophylaxis is needed after vaginal delivery. Because acute VTE is relatively uncommon, greater use of proposed guidelines [24,84,85] may be of value in improving management, but the involvement of clinicians with expertise in the management of these cases is also important.

Low molecular weight heparin for the treatment of venous thromboembolism in pregnancy: a case series

OBJECTIVES

To assess the use of low molecular weight heparin for the treatment of venous thromboembolism in pregnancy.

DESIGN

A prospective observational study.

SETTING

The maternity units in two university teaching hospitals and one district general teaching hospital.

POPULATION

Thirty-six consecutive women presenting with objectively diagnosed venous thromboembolism during pregnancy and the immediate puerperium.

METHODS

Treatment with the low molecular weight heparin enoxaparin, approximately 1 mg/kg s.c., twice daily, based on early pregnancy weight.

MAIN OUTCOME MEASURES

Peak anti-Xa activity (three hours post-injection), alterations in treatment, side effects and the use of regional anaesthesia.

RESULTS

In 33 women, the initial dose of enoxaparin provided satisfactory peak anti-Xa activity (median 0.8 u/mL, range 0.44-1.0 u/mL) and was continued. Three women required dose reduction since peak anti-Xa activities were above the therapeutic range (1.2, 1.2 and 1.1 u/mL). No woman developed thrombocytopaenia, haemorrhagic complication or further thromboembolic episode. Two women developed allergic skin reactions on enoxaparin and were changed to tinzaparin. Fifteen women had regional anaesthesia for delivery, with a reduced dose of enoxaparin (40 mg once daily), all without complication.

CONCLUSIONS

Enoxaparin is a safe and effective treatment for venous thromboembolism during pregnancy and confers a major advantage over unfractionated heparin through its simplified regimen of administration.

The acute management of venous thromboembolism in pregnancy

Pulmonary thromboembolism is the leading cause of maternal death in the UK. Optimal management of deep venous thrombosis and pulmonary thromboembolism requires an appreciation of risk factors, particularly thrombophilia, and signs or symptoms suggestive of venous thromboembolism, along with objective diagnosis and treatment with anticoagulants. Low molecular weight heparins are now replacing unfractionated heparin for the treatment of deep venous thrombosis and pulmonary thromboembolism in pregnancy because of the lower risk of side effects, ease of administration and reduced need for monitoring.

Septic shock resulting in death after operative delivery

BACKGROUND

We report a young woman who developed septic shock after operative delivery in the 32nd week of pregnancy. Clinical features, treatment modalities and prognosis of this high-mortality-rate disorder are presented and discussed.

CASE

A 24-year-old woman, gravida 1, para 1, was referred to our clinic in a confused state and immediately admitted to our emergency unit. She apparently had eclampsia antenatally. Termination of pregnancy with induction of labor and vacuum extraction had been employed in gestational week 32 of pregnancy. One day after delivery, her clinical and laboratory parameters worsened, so she was referred to our clinic. After a thorough physical examination and laboratory evaluation, the patient was diagnosed as having sepsis and disseminated intravascular coagulation. After blood and urine cultures were taken, aggressive management included volume repletion, antibiotics and positive inotropic therapy. Because she had persistent fever and unimproved laboratory values despite these therapies, the uterus and ovaries were thought to be the source of sepsis, and total abdominal hysterectomy and bilateral salpingo-oophorectomy were performed. Neither clinical nor laboratory parameters improved, and the patient died 28 days after delivery as a result of respiratory failure.

CONCLUSION

It is our purpose to emphasize that a rapid and appropriate decision for surgery may prevent the maternal mortality in obstetric septic shock patients. Successful management depends on early identification and aggressive treatment.