Hemostatic resuscitation in postpartum hemorrhage - a supplement to surgery

Thromboelastography versus Standard Coagulation Assays in Patients with Postpartum Hemorrhage

OBJECTIVE

 Thromboelastography (TEG), a point-of-care test that measures blood's dynamic viscoelastic properties, is routinely used to guide resuscitation in surgical specialties with high hemorrhage risk. Patients with ongoing postpartum hemorrhage (PPH) often develop coagulopathy and hypofibrinogenemia. Timely assessment of fibrinogen is crucial because cryoprecipitate for repletion requires thawing time prior to administration. TEG may provide rapid assessment of coagulopathy in ongoing hemorrhage but this has not been thoroughly studied. Our objective was to determine if TEG accurately reflects coagulopathy in ongoing PPH when compared with standard assays.

STUDY DESIGN

 This was a retrospective cohort study of people with ongoing PPH (quantified blood loss >1,000 mL), from January 1, 2016, to December 31, 2019. TEG variables and standard coagulation parameters were compared in patients who had both assays drawn simultaneously. As a secondary analysis, patients who had TEG were compared with those who did not. The Mann-Whitney, Fisher's exact, Kruskal-Wallis, Spearman's rho, and logistic regression tests were used for analysis. Significance was set at p < 0.05.

RESULTS

 A total of 680 patients were included, 69 of whom had TEG and coagulation parameters drawn simultaneously and were included in the primary analysis. The remainder were included in the secondary analysis. TEG variables and coagulation assays correlated significantly-prolonged R with increased PTT (rho 0.25, p = 0.04), prolonged K and decreased α angle with decreased fibrinogen (rho -0.61, p < 0.001; rho 0.24, p < 0.001), and decreased maximum amplitude with decreased platelets (rho 0.62, p < 0.001). Those who had thromboelastographic assays had higher blood loss and need for interventions to manage hemorrhage than those who did not.

CONCLUSION

 TEG correlated significantly with standard laboratory assays in ongoing PPH, including for patients with hypofibrinogenemia. Given the point-of-care nature and rapid turnaround time, TEG should be considered for timely hemorrhage evaluation and directed resuscitation of coagulopathy.

KEY POINTS

· TEG significantly correlates with standard laboratory measures of coagulopathy in postpartum hemorrhage, including in patients with hybofibrinogemia (fibrinogen <200).. · TEG is routinely used in nonobstetric hemorrhage, and should be considered in PPH.. · Due to the point-of-care nature, TEG may allow for rapid guided resuscitation, including fibrinogen..

Comparison of European recommendations about patient blood management in postpartum haemorrhage

Postpartum haemorrhage (PPH) is the leading cause of maternal mortality and morbidity worldwide. Some documents with practical recommendations for the management of PPH do not include the most updated directives. This review offers a quality comparison of the recommendations stated in Europe since 2015. A literature search was conducted to identify the documents published in Europe from 2015 to 2020 containing recommendations about management of PPH. The search returned 10 publications. A narrative synthesis and a summary of the information about PPH definition and its management were performed. Differences in the definition of PPH were identified: some documents considered the delivery procedure, and many publications included severity criteria. The therapeutic goal for red blood cells transfusion ranged from 6 to 9 g/dl. There were divergences in the need for considering haemostatic results before fresh frozen plasma transfusion. The therapeutic goal of platelet transfusion ranged from 50 x 10⁹ to 100 x 10⁹  μ/L. There was a wide consensus about the therapeutic goal of fibrinogen replacement (>2 g/L), but not about its use in an unmonitored or pre-emptive manner. Most publications included therapeutic approaches such as tranexamic acid and recombinant factor VII activated, but not prothrombin complex concentrate or coagulation factor XIII. The recommendations about PPH management offered in European documents are heterogeneous and have changed over time. The standardisation of all them could be useful to make progress in PPH clinical management and research which, in turn, could strongly impact in patient outcomes.

DIC in Pregnancy - Pathophysiology, Clinical Characteristics, Diagnostic Scores, and Treatments

Obstetrical hemorrhage and especially DIC (disseminated intravascular coagulation) is a leading cause for maternal mortality across the globe, often secondary to underlying maternal and/or fetal complications including placental abruption, amniotic fluid embolism, HELLP syndrome (hemolysis, elevated liver enzymes and low platelets), retained stillbirth and acute fatty liver of pregnancy. Various obstetrical disorders can present with DIC as a complication; thus, increased awareness is key to diagnosing the condition. DIC patients can present to clinicians who may not be experienced in a variety of aspects of thrombosis and hemostasis. Hence, DIC diagnosis is often only entertained when the patient already developed uncontrollable bleeding or multi-organ failure, all of which represent unsalvageable scenarios. Beyond the clinical presentations, the main issue with DIC diagnosis is in relation to coagulation test abnormalities. It is widely believed that in DIC, patients will have prolonged prothrombin time (PT) and partial thromboplastin time (PTT), thrombocytopenia, low fibrinogen, and raised D-dimers. Diagnosis of DIC can be elusive during pregnancy and requires vigilance and knowledge of the physiologic changes during pregnancy. It can be facilitated by using a pregnancy specific DIC score including three components: 1) fibrinogen concentrations; 2) the PT difference - relating to the difference in PT result between the patient's plasma and the laboratory control; and 3) platelet count. At a cutoff of ≥26 points, the pregnancy specific DIC score has 88% sensitivity, 96% specificity, a positive likelihood ratio (LR) of 22, and a negative LR of 0.125. Management of DIC during pregnancy requires a prompt attention to the underlying condition leading to this complication, including the delivery of the patient, and correction of the hemostatic problem that can be guided by point of care testing adjusted for pregnancy.

Viscoelastic Hemostatic Assays for Postpartum Hemorrhage

This article discusses the importance and effectiveness of viscoelastic hemostatic assays (VHAs) in assessing hemostatic competence and guiding blood component therapy (BCT) in patients with postpartum hemorrhage (PPH). In recent years, VHAs such as thromboelastography and rotational thromboelastometry have increasingly been used to guide BCT, hemostatic adjunctive therapy and prohemostatic agents in PPH. The three pillars of identifying hemostatic competence include clinical observation, common coagulation tests, and VHAs. VHAs are advantageous because they assess the cumulative contribution of all components of the blood throughout the entire formation of a clot, have fast turnaround times, and are point-of-care tests that can be followed serially. Despite these advantages, VHAs are underused due to poor understanding of correct technique and result interpretation, a paucity of widespread standardization, and a lack of large clinical trials. These VHAs can also be used in cases of uterine atony, preeclampsia, acute fatty liver of pregnancy, amniotic fluid embolism, placental abruption, genital tract trauma, surgical trauma, and inherited and prepartum acquired coagulopathies. There exists an immediate need for a point-of-care test that can equip obstetricians with rapid results on developing coagulopathic states. The use of VHAs in predicting and treating PPH, although in an incipient state, can fulfill this need.

Restrictive versus liberal fluid resuscitation strategy, influence on blood loss and hemostatic parameters in mild obstetric hemorrhage: An open-label randomized controlled trial. (REFILL study)

Background

Evidence for optimal hemostatic resuscitation in postpartum hemorrhage (PPH) is lacking. Liberal fluid administration may result in acidosis, hypothermia and coagulopathy.

Objective

We hypothesize that in early PPH a restrictive fluid administration results in less progression to moderate PPH.

Study design

In four Dutch hospitals we recruited women of 18 years and over, and more than 24 weeks pregnant. Exclusion criteria were: anticoagulant therapy, known coagulation disorders, pre-eclampsia, antenatal diagnosis of abnormally adhesive placenta, and a contraindication for liberal fluid therapy. We blindly randomized participants at 500 mL and ongoing blood loss in the third stage of labor between restrictive fluid administration (clear fluids 0.75–1.0 times the volume of blood lost) and liberal fluid administration (clear fluids 1.5–2.0 times the volume of blood lost). The primary outcome was progression to more than 1000 mL blood loss. Analyses were according to the intention-to-treat principle.

Results

From August 2014 till September 2019, 5190 women were informed of whom 1622 agreed to participate. A total of 252 women were randomized of which 130 were assigned to the restrictive group and 122 to the liberal group. In the restrictive management group 51 of the 130 patients (39.2%) progressed to more than 1000 mL blood loss versus 61 of the 119 patients (51.3%) in the liberal management group (difference, -12.0% [95%-CI -24.3% to 0.3%], p = 0.057). There was no difference in the need for blood transfusion, coagulation parameters, or in adverse events between the groups.

Conclusions

Although a restrictive fluid resuscitation in women with mild PPH could not been proven to be superior, it does not increase the need for blood transfusion, alter coagulation parameters, or cause a rise in adverse events. It can be considered as an alternative treatment option to liberal fluid resuscitation.

Trial registration

NTR3789.

Endogenous Heparin-Like Substances May Cause Coagulopathy in a Patient with Severe Postpartum Hemorrhage

Introduction

Postpartum hemorrhage (PPH) is associated with maternal morbidity and mortality. Accurate diagnosis of the cause of puerperal hemorrhage is as important as treatment strategies for resuscitation. We report a case of coagulation disorder caused by endogenous heparin-like substances in a PPH patient.

Case Presentation

A 30-year-old woman with no medical history of bleeding disorders suffered intractable hemorrhage following spontaneous delivery in a local hospital. The patient was transferred to the department of obstetrics of a superior hospital. On arrival, the patient was found to have severe hemorrhagic anemia, hemorrhagic shock, and disseminated intravascular coagulation. Active treatments were performed, but the patient continued bleeding. Laboratory testing, performed during early treatment, revealed that all coagulation factors were below normal. The differences between CK-TEG R-time (reaction time in citrated kaolin thromboelastography assay) and CKH-TEG R-time (reaction time in citrated kaolin with heparinase thromboelastography assay) suggested the presence of heparin activity. However, the patient's family denied heparin use prior to presentation. Thus, we deduced that endogenous heparin-like substances were the main cause of the coagulopathy. After receiving treatment with protamine, the patient stopped bleeding. Meanwhile, all coagulation parameters and the TEG assay results improved.

Conclusions

In this case report, TEG assay suggested the presence of heparin activity in a PPH patient, and treatment also highlighted the importance of analyzing different parameters in TEG.

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.

Thromboelastography Values Remain Hypercoagulative 6 Months After Obesity Surgery: a Pilot Study

PURPOSE

Obesity causes a prothrombotic state and is known as a predisposing factor for thromboembolic events. In this pilot study, we assessed the impact of surgery for obesity and the subsequent weight loss on blood coagulation using traditional coagulation tests and thromboelastography (TEG).

MATERIAL AND METHODS

We studied blood samples from 18 patients receiving bariatric surgery. Besides traditional blood coagulation tests and high-sensitivity C-reactive protein (hsCRP) as a marker of inflammation, the TEG parameters reaction time (R), kinetics time (K), angle (α), maximum amplitude (MA), clot strength (G), and lysis percent at 60 min (LY60) were determined preoperatively and on the first postoperative day and 6 months after surgery.

RESULTS

Altogether, 54 samples were analyzed. The median MA (71.3 mm), G (12,403.3 d/sc), and hsCRP (3.5 mg/l) were elevated preoperatively. The median hsCRP further increased on the first day postoperatively, but declined to the normal range 6 months after surgery, while MA and G remained elevated. In traditional coagulation tests, there was an increase in median fibrinogen and D-dimer postoperatively. D-dimer normalized (0.4 mg/l) during the study period, while the fibrinogen level (4.1 g/l) remained above the upper limit of normal.

CONCLUSIONS

Measured by TEG, patients receiving bariatric surgery have hemostatic abnormalities indicating hypercoagulation at the 6-month follow-up visit, suggesting an elevated risk for thromboembolic events for at least 6 months after surgery.

Patient blood management in obstetrics - Review

Patient blood management (PBM) aims to reduce red blood cell transfusion, minimize preoperative anemia, reduce intraoperative blood loss as well as optimize hemostasis, and individually manage postoperative anemia. Benefits include improved clinical outcome with a reduction in patient morbidity and mortality, but also lower hospital costs and shorter hospital length of stay. To date, it has been successfully implemented in several medical specialties, such as cardiac, trauma and orthopedic surgery. In obstetrics, postpartum hemorrhage (PPH) is one of the leading causes of maternal mortality. PBM has the potential to improve outcome of mother and child. However, pregnancy and childbirth pose a special challenge to PBM, and several adaptations compared to PBM in elective surgery are necessary. To date, awareness of the clinical advantages of PBM among obstetricians and midwifes regarding PBM and its concept in PPH is limited. In the following review, we therefore aim to present the current status quo in PBM in obstetrics and its challenges in the clinical routine.

Restrictive Versus Massive Fluid Resuscitation Strategy (REFILL study), influence on blood loss and hemostatic parameters in obstetric hemorrhage: study protocol for a randomized controlled trial

BACKGROUND

Postpartum hemorrhage (PPH) is associated with maternal morbidity and mortality and has an increasing incidence in high-resource countries, despite dissemination of guidelines, introduction of skills training, and correction for risk factors. Current guidelines advise the administration, as fluid resuscitation, of almost twice the amount of blood lost. This advice is not evidence-based and could potentially harm patients.

METHODS

All women attending the outpatient clinic who are eligible will be informed of the study; oral and written informed consent will be obtained. Where there is more than 500 ml blood loss and ongoing bleeding, patients will be randomized to care as usual, fluid resuscitation with 1.5-2 times the amount of blood loss or fluid resuscitation with 0.75-1.0 times the blood loss. Blood loss will be assessed by weighing all draping. A blood sample, for determining hemoglobin concentration, hematocrit, thrombocyte concentration, and conventional coagulation parameters will be taken at the start of the study, after 60 min, and 12-18 h after delivery. In a subgroup of women, additional thromboelastometric parameters will be obtained.

DISCUSSION

Our hypothesis is that massive fluid administration might lead to a progression of bleeding due to secondary coagulation disorders. In non-pregnant individuals with massive blood loss, restrictive fluid management has been shown to prevent a progression to dilution coagulopathy. These data, however, cannot be extrapolated to women in labor. Our objective is to compare both resuscitation protocols in women with early, mild PPH (blood loss 500-750 ml) and ongoing bleeding, taking as primary outcome measure the progression to severe PPH (blood loss > 1000 ml).

TRIAL REGISTRATION

Netherlands Trial Register, NTR 3789 . Registered on 11 January 2013.

Peripartum Haemorrhage: Haemostatic Aspects of the New German PPH Guideline

Summary Peripartum haemorrhage remains one of the main causes of maternal mortality world-wide. The German, Austrian and Swiss Societies of Gynaecology and Obstetrics have updated the current guidelines for the treatment of peripartum haemorrhage together with the German Society of Anaesthesiology and Intensive Care Medicine and the Society of Thrombosis and Haemostasis Research. The recommendations have been the result of a thorough review of the available scientific literature and a consensus process involving all members of the guideline group. A key element of the anaesthesiological and haemostatic management is the development of a multidisciplinary standard operating procedure combining surgical as well as medical and haemostatic treatments depending on the severity of bleeding. The guideline underscores the value of clinical and laboratory diagnostics of peripartum haemorrhage as early as possible, even pre-emptively. This allows for an early identification of causes of bleeding and a specific treatment. The guideline comprises evidence-based recommendations for the use of uterotonics, tranexamic acid and blood products such as factor concentrates, fresh frozen plasma, platelet concentrates, packed red blood cells, recombinant activated factor VII and desmopressin. In addition, recommendations for blood conservation strategies involving the use of cell salvage, permissive hypotension and transfusion triggers are given.

Massive transfusion: An update for the anesthesiologist

Exsanguination from trauma, gastrointestinal bleeding, and obstetric hemorrhage remains a major source of mortality across the planet. Continued research into resuscitation strategies and evolving technology and blood product storage has allowed for patient to undergo very large volume transfusions, even to the point of replacing a patient’s blood volume several times over. As massive transfusions have become more common, more studies have been performed delineating the exact patient population that would benefit, start- and stop-points of transfusions, complications and avoidance of the same. We discuss these points and provide information and strategies for massive transfusion.

Critical Care for the Obstetrician and Gynecologist: Obstetric Hemorrhage and Disseminated Intravascular Coagulopathy

Obstetric hemorrhage accounts for 5% all deliveries in the United States and accounts for high maternal morbidity and mortality. Many hemorrhages are secondary to uterine atony and are quickly ameliorated with appropriate uterotonic use. However, for a subset of cases, severe hemorrhage may require advanced resuscitative techniques, and innovative procedural and surgical techniques. This article guides a provider through such a resuscitation.

Preventing deaths due to haemorrhage

Prevention of deaths from obstetric haemorrhage requires effective health systems including family planning, commodities, personnel, infrastructure and ultimately universal access to comprehensive obstetric care for women giving birth. The main causes of death associated with antepartum haemorrhage are placental abruption, placenta praevia and uterine rupture. Preventive measures include preconceptual folate supplementation, management of hypertensive disorders, early diagnosis of placenta praevia and use of uterine stimulants cautiously, particularly misoprostol. Preventive measures for post-partum haemorrhage include routine active management of the third stage of labour. Treatment involves a cascade of increasingly invasive interventions in rapid sequence until the bleeding is stopped. These interventions include fluid resuscitation, removal of the placenta, bimanual uterine compression, uterotonics, tranexamic acid, suturing of lower genital tract injury, blood product replacement, balloon tamponade, laparotomy, stepwise uterine devascularization, uterine compression sutures and hysterectomy. Emergency temporizing measures include application of the non-pneumatic anti-shock garment, and at laparotomy, aortic compression and uterine tourniquet application. The effectiveness of treatment methods and the optimal dosage of misoprostol are research priorities. Interesting new approaches include transvaginal uterine artery clamping and suction uterine tamponade.

Massive transfusion: red blood cell to plasma and platelet unit ratios for resuscitation of massive hemorrhage

PURPOSE OF REVIEW

The aim of this short study is to review recently published data bearing on how to resuscitate massive uncontrolled hemorrhage.

RECENT FINDINGS

New data inform our understanding of the mechanisms of the acute coagulopathy of trauma, the median time to death of trauma patients with uncontrolled hemorrhage, the effects of blood product composition on the coagulation capacity of infused resuscitation mixtures, the outcomes of patients resuscitated according to common massive transfusion protocols in clinical situations associated with massive hemorrhage, and who might benefit from balanced, blood-product-based resuscitation. Importantly, the trial methods, blood bank methods, and primary outcomes of the Pragmatic Randomized Optimal Plasma and Platelet Ratios (PROPPR) trial were recently published. Resuscitation with a 1 : 1 : 1 ratio of units of plasma and platelets to red blood cells was well tolerated and reduced hemorrhagic mortality during resuscitation in the PROPPR trial.

SUMMARY

The bulk of currently available data support the use of a 1 : 1 : 1 ratio for the resuscitation of patients with severe injury, shock, and uncontrolled hemorrhage. The application of this formulaic approach to massive blood product-based resuscitation in other clinical situations is less well supported in the literature.

Massive obstetric hemorrhage: Current approach to management

Massive obstetric hemorrhage is a major cause of maternal mortality and morbidity worldwide. It is defined (among others) as the loss of>2,500ml of blood, and is associated to a need for admission to critical care and/or hysterectomy. The relative hemodilution and high cardiac output found in normal pregnancy allows substantial bleeding before a drop in hemoglobin and/or hematocrit can be identified. Some comorbidities associated with pregnancy can contribute to the occurrence of catastrophic bleeding with consumption coagulopathy, which makes the situation even worse. Optimization, preparation, rational use of resources and protocolization of actions are often useful to improve outcomes in patients with postpartum hemorrhage. Using massive obstetric hemorrhage protocols is useful for facilitating rapid transfusion if needed, and can also be cost-effective. If hypofibrinogenemia during the bleeding episode is identified, early fibrinogen administration can be very useful. Other coagulation factors in addition to fibrinogen may be necessary during postpartum hemorrhage replacement measures in order to effectively correct coagulopathy. A hysterectomy is recommended if the medical and surgical measures prove ineffective.