Analysis of complement deposition and viral RNA in placentas of COVID-19 patients

COVID-19, the disease caused by the novel Coronavirus, SARS-CoV-2, is increasingly being recognized as a systemic thrombotic and microvascular injury syndrome that may have its roots in complement activation. We had the opportunity to study the placental pathology of five full-term births to COVID-19 patients. All five exhibited histology indicative of fetal vascular malperfusion characterized by focal avascular villi and thrombi in larger fetal vessels. Vascular complement deposition in the placentas was not abnormal, and staining for viral RNA and viral spike protein was negative. While all cases resulted in healthy, term deliveries, these findings indicate the systemic nature of COVID-19 infection. The finding of vascular thrombosis without complement deposition may reflect the systemic nature of COVID-19's procoagulant effects unrelated to systemic complement activation.

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This paper explores thrombosis in the placentas COVID-19-positive patients at our hospital

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Potential prothrombotic mechanisms are explored.

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Direct infection of the placentas is ruled out as a cause.

Thrombin/PAR-1 activation induces endothelial damages via NLRP1 inflammasome in gestational diabetes

Gestational diabetes mellitus (GDM) is associated with an increased risk of progressing to type 2 DM and cardiovascular disease; however, the pathogenesis is still poorly understood. This study was to investigate roles of thrombin and its receptor protease-activated receptor 1 (PAR-1) and NLRP1 inflammasome in endothelial injury in GDM condition. Umbilical cord and plasma of GDM patients and high glucose (HG) cultured human umbilical vein endothelial cells (HUVECs) were used to examine the pathological changes of these pathways. Meanwhile, ameliorative effects and potential mechanisms of a natural product sarsasapogenin (Sar) were investigated in HUVECs. Thrombin/PAR-1 pathway, advanced glycation endproducts (AGEs) and their receptor (RAGE) axis, and the nucleotide-binding domain and leucine-rich repeat containing protein 1 (NLRP1) inflammasome were activated in GDM condition and HG-cultured HUVECs, accompanied by endothelial injury (decreased cell viability and increased lactate dehydrogenase release). Nevertheless, thrombin inhibition or PAR-1 antagonism caused decreases in AGEs formation and RAGE expression in HG-cultured HUVECs, while AGEs inhibition or RAGE antagonism declined PAR-1 expression not thrombin activity. Furthermore, thrombin inhibition or PAR-1 antagonism restrained NLRP1 inflammasome activation in HG-cultured HUVECs; meanwhile, NLRP1 expression and interleukin 18 levels were remarkably reduced in HG-cultured HUVECs after PAR-1 knockdown. Interestingly, Sar co-treatment could suppress thrombin/PAR-1 pathway, NLRP1 inflammasome, and AGEs/RAGE axis. Together, endothelial damages in GDM were likely due to enhanced interaction between AGEs/RAGE axis and thrombin/PAR-1 pathway, followed by NLRP1 inflammasome activation. Moreover, Sar may act as a protective agent against endothelial injury in chronic HG condition.

Patient blood management (PBM) in pregnancy and childbirth: literature review and expert opinion

PURPOSE

Patient blood management [PBM] has been acknowledged and successfully introduced in a wide range of medical specialities, where blood transfusions are an important issue, including anaesthesiology, orthopaedic surgery, cardiac surgery, or traumatology. Although pregnancy and obstetrics have been recognized as a major field of potential haemorrhage and necessity of blood transfusions, there is still little awareness among obstetricians regarding the importance of PBM in this area. This review, therefore, summarizes the importance of PBM in obstetrics and the current evidence on this topic.

METHOD

We review the current literature and summarize the current evidence of PBM in pregnant women and postpartum with a focus on postpartum haemorrhage (PPH) using PubMed as literature source. The literature was reviewed and analysed and conclusions were made by the Swiss PBM in obstetrics working group of experts in a consensus meeting.

RESULTS

PBM comprises a series of measures to maintain an adequate haemoglobin level, improve haemostasis and reduce bleeding, aiming to improve patient outcomes. Despite the fact that the WHO has recommended PBM early 2010, the majority of hospitals are in need of guidelines to apply PBM in daily practice. PBM demonstrated a reduction in morbidity, mortality, and costs for patients undergoing surgery or medical interventions with a high bleeding potential. All pregnant women have a significant risk for PPH. Risk factors do exist; however, 60% of women who experience PPH do not have a pre-existing risk factor. Patient blood management in obstetrics must, therefore, not only be focused on women with identified risk factor for PPH, but on all pregnant women. Due to the risk of PPH, which is inherent to every pregnancy, PBM is of particular importance in obstetrics. Although so far, there is no clear guideline how to implement PBM in obstetrics, there are some simple, effective measures to reduce anaemia and the necessity of transfusions in women giving birth and thereby improving clinical outcome and avoiding complications.

CONCLUSION

PBM in obstetrics is based on three main pillars: diagnostic and/or therapeutic interventions during pregnancy, during delivery and in the postpartum phase. These three main pillars should be kept in mind by all professionals taking care of pregnant women, including obstetricians, general practitioners, midwifes, and anaesthesiologists, to improve pregnancy outcome and optimize resources.

Coagulation abnormalities and bleeding in pregnancy: an anesthesiologist's perspective

During pregnancy, the procoagulant activity increases (manifested by elevation in factor VII, factor VIII, factor X, and fibrinogen levels), while the anticoagulant activity decreases (characterized by reduction in fibrinolysis and protein S activity), resulting in hypercoagulation. Standard coagulation tests, such as prothrombin time or activated partial thromboplastin time, are still used despite the lack of evidence supporting its accuracy in evaluating the coagulation status of pregnant women. Thromboelastography and rotational thromboelastometry, which are used to assess the function of platelets, soluble coagulation factors, fibrinogen, and fibrinolysis, can replace standard coagulation tests. Platelet count and function and the effect of anticoagulant treatment should be assessed to determine the risk of hematoma associated with regional anesthesia. Moreover, anesthesiologists should monitor patients for postpartum hemorrhage (PPH), and attention should be paid when performing rapid coagulation tests, transfusions, and prohemostatic pharmacotherapy. Transfusion of a high ratio of plasma and platelets to red blood cells (RBCs) showed high hemostasis success and low bleeding-related mortality rates in patients with severe trauma. However, the effects of high ratios of plasma and platelets and the ratio of plasma to RBCs and platelets to RBCs in the treatment of massive PPH were not established. Intravenous tranexamic acid should be administered immediately after the onset of postpartum bleeding. Pre-emptive treatment with fibrinogen for PPH is not effective in reducing bleeding. If fibrinogen levels of less than 2 g/L are identified, 2–4 g of fibrinogen or 5–10 ml/kg cryoprecipitate should be administered.

Tranexamic acid as adjuvant treatment for postpartum hemorrhage: a systematic review protocol

OBJECTIVE

The objective of this review is to evaluate the effectiveness of intravenous administration of tranexamic acid (TXA) within three hours of birth in mothers with a diagnosis of postpartum hemorrhage (PPH).

INTRODUCTION

Postpartum hemorrhage, that is, blood loss exceeding 500 mL for vaginal births or 1000 mL for cesarean sections within 24 hours of delivery, is the leading cause of maternal deaths worldwide. The World Health Organization recommends intravenous TXA as an adjuvant therapy for the treatment of PPH, in addition to standard recommended treatments, within three hours of birth. This review will determine whether TXA administration to patients experiencing PPH leads to a reduction in blood loss, the requirement for transfusion of packed red blood cells and the need for emergency hysterectomies, in both developed and developing nations.

INCLUSION CRITERIA

This review will consider studies that include women under 40 with a diagnosis of postpartum hemorrhage. Studies that evaluate intravenous administration of TXA within three hours of birth as adjuvant treatment of postpartum hemorrhage will be considered. The comparator will be groups that have not received TXA as part of the treatment for postpartum hemorrhage, with or without placebo.

METHODS

MEDLINE, Embase, CINAHL, CENTRAL, Scopus, Web of Science and ProQuest Nursing and Allied Health will be searched for eligible studies. The search for unpublished studies will include: ProQuest Dissertations and Theses (PQDT), ClinicalTrials.gov and New York Academy of Medicine Grey Literature Report. Retrieval of full-text studies, assessment of methodological quality and data extraction will be performed independently by two reviewers. Meta-analysis will be performed, if possible.

Management of post-partum hemorrhage and the role of the obstetric anesthesiologist

PURPOSE OF REVIEW

The landscape of post-partum hemorrhage management is rapidly changing. Modifications to definitions, bundles, and care plans occur frequently with management strategies becoming more complex. It has become apparent that the management of these patients requires a multidisciplinary approach with the involvement of obstetricians, anesthesiologists, gynecologist/oncologists, nursing, and care associates. This review article is meant to be an evidence-based review of post-partum hemorrhage with practical recommendations and a look at future directions of the management of post-partum hemorrhage from the vantage point of the obstetric anesthesiologist in an effort to enhance the collaborative treatment of this at risk population.

Case Report: Anesthetic management for Cesarean section in a parturient with unspecified inherited bleeding disorder

Neuraxial anesthesia, as the standard of care for Cesarean deliveries, is associated with decreased blood loss. However, parturients with inherited bleeding disorders are at increased risk for epidural hematomas. A small retrospective study has shown that parturients with known factor deficiencies can safely undergo neuraxial anesthesia once the specific factors are replenished. We present a patient who had a considerably increased risk of peripartum bleeding from an unspecified inherited bleeding disorder and was provided a successful neuraxial anesthetic without complications. We discuss the multidisciplinary approach among the surgeons, anesthesiologists, hematologist, and nursing staff to maximize patient safety and comfort.

Perioperative management of the bleeding patient

Perioperative bleeding remains a major complication during and after surgery, resulting in increased morbidity and mortality. The principal causes of non-vascular sources of haemostatic perioperative bleeding are a preexisting undetected bleeding disorder, the nature of the operation itself, or acquired coagulation abnormalities secondary to haemorrhage, haemodilution, or haemostatic factor consumption. In the bleeding patient, standard therapeutic approaches include allogeneic blood product administration, concomitant pharmacologic agents, and increasing application of purified and recombinant haemostatic factors. Multiple haemostatic changes occur perioperatively after trauma and complex surgical procedures including cardiac surgery and liver transplantation. Novel strategies for both prophylaxis and therapy of perioperative bleeding include tranexamic acid, desmopressin, fibrinogen and prothrombin complex concentrates. Point-of-care patient testing using thromboelastography, rotational thromboelastometry, and platelet function assays has allowed for more detailed assessment of specific targeted therapy for haemostasis. Strategic multimodal management is needed to improve management, reduce allogeneic blood product administration, and minimize associated risks related to transfusion.

Extracellular Vesicles in Human Reproduction in Health and Disease

Extensive evidence suggests that the release of membrane-enclosed compartments, more commonly known as extracellular vesicles (EVs), is a potent newly identified mechanism of cell-to-cell communication both in normal physiology and in pathological conditions. This review presents evidence about the formation and release of different EVs, their definitive markers and cargo content in reproductive physiological processes, and their capacity to convey information between cells through the transfer of functional protein and genetic information to alter phenotype and function of recipient cells associated with reproductive biology. In the male reproductive tract, epididymosomes and prostasomes participate in regulating sperm motility activation, capacitation, and acrosome reaction. In the female reproductive tract, follicular fluid, oviduct/tube, and uterine cavity EVs are considered as vehicles to carry information during oocyte maturation, fertilization, and embryo-maternal crosstalk. EVs via their cargo might be also involved in the triggering, maintenance, and progression of reproductive- and obstetric-related pathologies such as endometriosis, polycystic ovarian syndrome, preeclampsia, gestational diabetes, and erectile dysfunction. In this review, we provide current knowledge on the present and future use of EVs not only as biomarkers, but also as therapeutic targeting agents, mainly as vectors for drug or compound delivery into target cells and tissues.

Five years' experience in an anesthesiology antenatal clinic for high-risk patients

INTRODUCTION

The aim, of this study is to describe our approach and outcomes in an outpatient anesthesia/analgesia antepartum clinic among ambulatory high-risk obstetric patients.

METHODS

This was a retrospective evaluation of the activity of the anesthesiology antenatal clinic from its inception in 2010 until 2016 (a 5-year period). The clinic works in collaboration with the Department of Obstetrics and Gynecology. The catchment area of the study University Affiliated Hospital attends a multiethnic population characterized by high parity.

RESULTS

There were 241 referrals over the 5 years, each of whom was discharged with a consult and a delivery management plan and 228 (95%) of which were performed as planned. Mean gestational age at consultation was 34.4 weeks (range: 20-37). There were no preconceptional consultation. No limitations regarding mode of anesthesia/analgesia was considered for 47% of the referrals. Nulliparous women accounted for 50% of the referrals and 17% were in their second pregnancy. The greatest number of referrals (30%) was for musculoskeletal conditions. No maternal death encountered. The mode of delivery was vaginal in 139 (65%) women; elective cesarean section in 44 (21%) women; and emergent cesarean section in 30 (14%) women. The neonatal outcomes were unremarkable; 210 (87%) in hospital births, 97.1% had an a 5' Apgar score of 9.

CONCLUSION

Our findings reveal the need for high-risk obstetric patients consult with a dedicated obstetric anesthesiologist to devise a management plan for labor and delivery that is tailored to their comorbidity and obstetric status, to ensure an optimum outcome for mother and child.

Critical Care in Obstetrics: Where are We

Maternal mortality is disastrous news for the society, family, newborn, and the obstetrician. Yet, we all who are care providers to these apparently healthy women carrying another life within them are dumbfounded by the clinical conditions arising due to the pregnancy or the effects of the pregnancy, that it becomes difficult to provide an ideal care to them. The rapid uprising of a condition and the worsening of commonly occurring benign conditions-preeclampsia, hemorrhage, etc., necessitates that all obstetricians are well versed with the physiological changes and should be able to not only provide the best of obstetric care to the mother and the newborn but also perform or assist in performance of life-saving procedures.

Intravenous Remifentanil Analgaesia for an Obstetric Patient with Type I Neurofibromatosis and a Factor V Leiden Mutation

Type I neurofibromatosis is characterised by altered skin pigmentation and the growth of benign tumours, particularly along the peripheral nerves and central nervous system. We report a 36-year-old primigravida woman in labour who was admitted to the obstetric suite of the Hospital Sant Joan de Déu, Barcelona, Spain, in 2007 with hypothyroidism, type I neurofibromatosis and a factor V Leiden mutation. Due to a lack of cranial and spinal imaging data, an epidural was not indicated; instead, continuous intravenous remifentanil analgaesia was administered. The remifentanil infusion was self-titrated by the patient using a visual analogue scale, with the dosage ranging from 0.01 to 0.25 μg/kg/minute. Due to rotational dystocia, Kjelland-type forceps were used during the delivery. After birth, the infant was found to have Apgar scores of 9 and 10, with no maternal or neonatal adverse effects observed. Although still controversial, remifentanil may be a successful alternative for analgaesia in similar cases; however, the specific risks and benefits for each patient should be considered prior to administration.

Association of antenatal antithrombin activity with perinatal liver dysfunction: A prospective multicenter study

BACKGROUND AND AIM

Liver dysfunction with decreased antithrombin (AT) activity and/or thrombocytopenia is life threatening in pregnant women. Whether AT is clinically useful for prediction of liver dysfunction remains unclear.

METHODS

A total of 541 women were registered prospectively at gestational week 34.7 (20.0-41.4) with available data on antenatal AT and platelet count (PLC).

RESULTS

Liver dysfunction defined as serum aspartate aminotransferase > 45 IU/L concomitant with lactate dehydrogenase > 400 IU/L occurred in five women antenatally (≤ 2 weeks before delivery) and in 17 women post-partum (within 1 week post-partum). Median (5th-95th) antenatal value was 85 (62-110)% for AT and 202 (118-315) × 10⁹ /L for PLC in the 541 women and was significantly lower in women with than without perinatal liver dysfunction; 75 (51-108) versus 86 (62-110)% and 179 (56-244) versus 203 (121-316) × 10⁹ /L, respectively. Nineteen (86%) women with liver dysfunction showed AT ≤ 62% or thrombocytopenia (PLC ≤ 118 × 10⁹ /L) perinatally, but five lacked thrombocytopenia throughout the perinatal period. The best cut-off (AT, 77%; PLC, 139 × 10⁹ /L) suggested by receiver operating characteristic curve gave antenatal AT and PLC sensitivity of 59% and 41% with positive predictive value of 8.6% and 14%, respectively, and combined use of AT and PLC improved sensitivity to 73% (16/22) with positive predictive value of 9.2% for prediction of perinatal liver dysfunction.

CONCLUSIONS

Reduced AT not accompanied by thrombocytopenia can precede liver dysfunction. Clinical introduction of AT may enhance the safety of pregnant women.

How I treat recurrent venous thromboembolism in patients receiving anticoagulant therapy

Oral anticoagulant therapy for venous thromboembolism is very effective. When oral anticoagulants are managed well, the risk of recurrence is approximately 2 per 100 patient-years. The main reasons for a breakthrough event are underlying disease and subtherapeutic drug levels. The most common underlying disease that results in recurrence on treatment is cancer. Subtherapeutic drug levels can be caused by poor adherence to the drug regimen, interactions with other drugs or food, or inappropriate dosing. It is important to investigate and understand the cause whenever such an event occurs and to improve management of anticoagulants thereby avoiding further recurrences. Here we present 4 illustrative cases together with a discussion of the underlying pathology. Whereas the mechanisms are usually quite well understood, the management of further anticoagulation after a breakthrough event is based on minimal or no clinical trial evidence.

Hemostatic issues in pregnancy-induced liver disease

Liver diseases may be accompanied by profound changes in the hemostatic system including thrombocytopenia, decreased plasma levels of pro- and anticoagulants, and alterations in plasma levels of fibrinolysis. The net effect of the hemostatic changes in chronic and acute liver diseases is a hemostatic system that is in relative balance due to the simultaneous decline in pro- and antihemostatic drivers. A unique category of liver diseases are those induced by pregnancy. In acute fatty liver of pregnancy, profound hemostatic changes occur, which may be caused by a combination of liver failure and disseminated intravascular coagulation. Hemostatic changes in preeclampsia and HELLP syndrome are dominated by thrombocytopenia, although alterations in plasmatic coagulation may also occur. Post-partum bleeds, bleeding from cesarean section wounds, and hepatobiliary bleeds may occur in both patient groups. Patients with intrahepatic cholestasis of pregnancy do not show clinically relevant hemostatic alterations, despite biochemical evidence of liver injury.

Sheehan syndrome

Sheehan syndrome or postpartum hypopituitarism is a condition characterized by hypopituitarism due to necrosis of the pituitary gland. The initial insult is caused by massive postpartum haemorrhage (PPH), leading to impaired blood supply to the pituitary gland, which has become enlarged during pregnancy. Small sella turcica size, vasospasms (caused by PPH) and/or thrombosis (associated with pregnancy or coagulation disorders) are predisposing factors; autoimmunity might be involved in the progressive worsening of pituitary functions. Symptoms are caused by a decrease or absence of one or more of the pituitary hormones, and vary, among others, from failure to lactate and nonspecific symptoms (such as fatigue) to severe adrenal crisis. In accordance with the location of hormone-secreting cells relative to the vasculature, the secretion of growth hormone and prolactin is most commonly affected, followed by follicle-stimulating hormone and luteinizing hormone; severe necrosis of the pituitary gland also affects the secretion of thyroid-stimulating hormone and adrenocorticotropic hormone. Symptoms usually become evident years after delivery, but can, in rare cases, develop acutely. The incidence of Sheehan syndrome depends, to a large extent, on the occurrence and management of PPH. Sheehan syndrome is an important cause of hypopituitarism in developing countries, but has become rare in developed countries. Diagnosis is based on clinical manifestations combined with a history of severe PPH; hormone levels and/or stimulation tests can confirm clinical suspicion. Hormone replacement therapy is the only available management option so far.

Findings and differential diagnosis of fetal intracranial haemorrhage and fetal ischaemic brain injury: what is the role of fetal MRI?

Ventriculomegaly (VM) is a non-specific finding on fetal imaging. Identification of the specific aetiology is important, as it affects prognosis and may even change the course of current or future pregnancies. In this review, we will focus on the application of fetal MRI to demonstrate intracranial haemorrhage and ischaemic brain injury as opposed to other causes of VM. MRI is able to identify the specific aetiology of VM with much more sensitivity and specificity than ultrasound and should be considered whenever VM is identified on obstetric ultrasound. Advances in both fetal and neonatal MRI have the potential to shed further light on mechanisms of brain injury and the impact of chronic hypoxia; such information may guide future interventions.