Management of severe peri-operative bleeding: Guidelines from the European Society of Anaesthesiology and Intensive Care: Second update 2022

Real-time global coagulation assay via ordered porous layer interferometry using silica colloidal crystal film

BACKGROUND

The coagulation process is inherently complex, and conventional diagnostic techniques are typically only capable of detecting single coagulation factors, lacking capacity to assess the overall coagulation function of the patient. Therefore, it is thus imperative to develop a novel, global coagulation assay for the diagnosis of hemorrhagic and thrombotic disorders and to evaluate the therapeutic efficacy of anticoagulant drugs. The ordered porous layer interferometry technology, developed using silica colloidal crystal (SCC) film as sensing substrate, is characterized by low cost, real-time, and convenient operation. Furthermore, entire biological events process can be detected by migration of the SCC film interference spectra.

RESULTS

In this study, we developed a global coagulation assay with ordered porous layer interferometry by SCC film, a model of coagulation was created using fibrinogen and thrombin. The results demonstrated that this method could analyze the effect of different thrombin activities and different fibrinogen concentrations on the coagulation process. The performance of the coagulation assay was further validated using real blood samples and the method was found to have excellent detection capacity for different concentrations of CaCl2, which could trigger coagulation process. Hypercoagulable and hypocoagulable samples were tested by setting different biochemical conditions, and it could distinguish blood samples from different states significantly. Clinical samples were collected and the approach was compared with standard coagulation assays with satisfactory clinical correlation.

SIGNIFICANCE

This global coagulation assay is simple, rapid and real-time, and does not require various biochemical reagents. The whole process of coagulation reaction can be recorded, and multiple coagulation indicators can be obtained in one test. It is anticipated to provide a novel low-cost and powerful method for clinical coagulation testing.

Electronic health records reveal variations in the use of blood units by hour and medical specialty

BACKGROUND AND OBJECTIVES

Efficient blood supply chain requires accurate demand estimates. Blood demand is created by clinicians making transfusion decisions based on patient status. To better understand the use of blood units, we tracked their use hourly and across a large hospital organization.

MATERIALS AND METHODS

We analysed blood use in adult patients over 2021-2022 at HUS Helsinki University Hospital, serving a population of 1.7 million and consuming a third of blood units used in Finland. We utilized electronic health records (EHR) to map transfusions to patient demographics, diagnoses, medical specialties, treatment events, surgical procedures and laboratory values. Data were matched to transfusions of red blood cells, platelets and plasma using timestamps and treatment episodes.

RESULTS

In total, 107,331 units were transfused to 19,637 unique patients in 50,978 transfusion episodes. Most transfusions occurred in emergency settings, with 61.5% of use driven by emergency department admissions. The most common diagnoses were malignant neoplasms, anaemia and cardiovascular diseases. In total, 47.9% of transfusions were associated with a surgical procedure. Of these, 72.9% were for urgent surgery. Blood use peaked in the early evening and was lowest during morning office hours.

CONCLUSION

The study offers a comprehensive picture of blood use in one of the largest European hospital organizations. In addition to elective use, a significant portion of blood demand is driven by urgent and emergency needs, which introduce some uncertainty in predicting blood use. Future studies should aim to understand both elective and emergency blood use to help improve demand estimates.

Updates in perioperative hemostasis in the pediatric surgical patient

PURPOSE OF REVIEW

Maintaining hemostasis in pediatric patients undergoing major surgery presents unique challenges for the anesthesiologist. This review presents the most recent updates on pediatric perioperative bleeding and hemostasis management.

RECENT FINDINGS

Patient blood management (PBM) programs remain scarcely implemented, but recent evidence for restrictive transfusion thresholds and reduction in allogeneic blood products in the pediatric population is growing. Notable updates include support for pediatric PBM programs, restrictive transfusion thresholds, increased use of viscoelastic testing, safety and efficacy of whole blood, and management of coagulopathy in trauma.

SUMMARY

PBM programs and their key components have gained traction in the pediatric population in recent years: treating preoperative anemia, optimizing coagulation, and tolerating physiologic anemia through restrictive transfusion thresholds. Further evidence in the pediatric population is needed to guide the anesthesiologist.

Perioperative Management During Liver Transplantation: A National Survey From the French Special Interest Group in "Liver Anesthesiology and Intensive Care"

BACKGROUND

Perioperative management practices in liver transplantation (LT) evolve very quickly. There are few specific recommendations, often based on a low level of evidence, resulting in wide heterogeneity of practices.

METHODS

We performed a survey in all 16 French centers in 2021 by focusing on center organization, preoperative cardiovascular assessment, antimicrobial prophylaxis, hemostasis management, intraoperative use of hemodynamic monitoring and renal replacement therapy, immunosuppression, and postoperative prevention of arterial complications and compared it with current recommendations.

RESULTS

The organization of perioperative LT care involved 1 single team throughout the perioperative LT process in 7 centers (43.7%). The coronary evaluation was systematic in one-third of the centers and guided by risk factors in the other centers. Antibiotic prophylaxis was strictly intraoperative in only 7 centers (44%). Antifungal prophylaxis targeting high-risk LT recipients was administered in 15 centers (93%). Intraoperative coagulation assessment was based on standard coagulation tests in 8 centers (50%), on viscoelastic assays in 4 centers (25%), and both methods in 4 centers (25%). Hemodynamic monitoring practices greatly varied between centers.Concerning immunosuppression, molecules and dosages were heterogeneous. Aspirin was systematically administered in one-third of cases (6 centers; 37.5%). Of the 21 recommendations tested, the concordance rate was 100% for 3 recommendations and <50% for 7 recommendations.

CONCLUSIONS

Our study precisely describes French practices regarding LT in perioperative care and highlights the paucity of data in this setting, leading to very weak recommendations that are poorly followed in LT centers.

Outcomes, cost-effectiveness, and ethics in patient blood management

PURPOSE OF THE REVIEW

In this narrative review, we evaluate the recent evidence for benefits, cost-effectiveness, and ethical considerations of patient blood management (PBM) programs.

RECENT FINDINGS

PBM programs are able to reduce the amount of red blood cell transfusion by 20-40% and the risk of reoperation. Lower morbidity and mortality due to PBM implementation were only shown in retrospective studies with a before-and-after design but not in randomized controlled trials. PBM is very likely to be cost-effective when reduced blood transfusion can be accomplished through low-cost interventions, such as administration of oral iron or antifibrinolytics. Further, cost-efficacy can also be achieved by reducing postoperative morbidity and length of hospital stay. Of note, cost-efficacy of PBM interventions might be better in patients at high bleeding risk. Finally, aiming to improve patient's outcome while minimizing transfusion-induced complications, PBM seems highly ethical.

SUMMARY

PBM is an important concept as it promotes the rational use of allogeneic blood products and reduces transfusion and wastage of precious and limited blood products.

Restoring hemostasis with prothrombin complex concentrate: benefits and risks in trauma-induced coagulopathy

PURPOSE OF THIS REVIEW

To provide evidence for the use of prothrombin complex concentrate (PCC) as a potential hemostatic treatment for trauma-induced coagulopathy with and without anticoagulants.

RECENT FINDINGS

PCC is effective in enhancing thrombin generation and achieving hemostasis in traumatized patients under anticoagulants. For vitamin K antagonist (VKA) reversal, it shows superior efficacy over fresh frozen plasma, achieving rapid normalization of the international normalized ratio normalization and reduced transfusion needs. In direct oral anticoagulant (DOAC)-associated bleeding, PCC offers an alternative when specific antidotes are unavailable. However, evidence from randomized trials in the field of trauma and coagulopathy is limited, and the results have shown conflicting outcomes in terms of mortality reduction. Further, following PCC application, thromboembolic risks remain a particular concern. Monitoring tools such as thrombin generation assays and point-of-care tests show promise but are not universally available.

SUMMARY

PCC is a valuable option for managing coagulopathy in specific settings, especially VKA and DOAC reversal. Based on current evidence, we caution against the use of PCC as a versatile hemostatic agent suitable for indications involving multiple clotting factor deficiencies for uncontrolled coagulopathic bleeding in trauma or other clinical settings outside anticoagulation reversal. The risk vs. benefit profile should be carefully examined, similar to any other agent.

[Diagnostics and management of perioperative bleeding disorders]

Perioperative bleeding is and remains a major complication during and after surgical interventions, resulting in increased morbidity and mortality. The main causes of a non-primary vascular-related bleeding are congenital or multifactorial pre-existing hemostatic disorders that have not yet been diagnosed, the operating procedure itself and acquired hemostatic abnormalities as a secondary phenomenon, e.g., after excessive volume depletion in hypothermia, trauma or extracorporeal circulation, concomitant hypothermia and loss or consumption of coagulation factors and thrombocytes. Beginning with the preoperative preparation, including an extensive medical history, the detection of potential risk factors for increased bleeding including the precise description of current medication is required and prophylactic strategies and procedures should be initiated. In cases of excessive bleeding it is essential to implement adequate diagnostic and therapeutic algorithms, which are suitable for the partly complex and variable alterations of the hemostasis (e.g., in interventions after trauma or with extracorporeal circulation). A multimodal management is necessary to improve the patient's outcome, to limit the administration of blood products to that which is absolutely necessary and to minimize the risks associated with transfusion.

Towards optimization in the use of hemostatic agents and blood products in the early treatment of patients with traumatic brain injury (TBI)

PURPOSE OF THE REVIEW

The treatment of patients with traumatic brain injury (TBI) with subsequently evolving hemostatic failure and hemorrhagic lesion progression remains challenging. New studies highlight windows of opportunity for treatment optimization.

RECENT FINDINGS

Results from recent randomized studies suggest an earlier treatment with antifibrinolytic tranexamic acid at a higher initial bolus dose. There seems to be a new window of opportunity for the early prehospital use of thawed plasma. Viscoelastic-based goal-directed treatment strategies are still not delivered timely in most patients although a recent meta-analysis has confirmed a survival benefit with this approach.

SUMMARY

Mortality in TBI with subsequent evolving hemostatic failure can be reduced through treatment optimization delivering early prehospital high-dose tranexamic acid and in-hospital goal-directed treatment algorithms to timely correct coagulopathy and restore hemostasis.

Patient Blood Management: A conceptual and analytical vision from the leadership in Spain

The evolution of blood saving programs to Patient Blood Management (PBM) represents a broader and more comprehensive approach to optimize the use of the patient's own blood, thus improving clinical outcomes and minimizing the risks associated with allogeneic blood transfusion with a holistic view of socio-economic sustainability. Implementing the strategies of the three PBM pillars in any hospital center involves a transversal change throughout the organization in which it can be very useful to apply the strategy defined by Kotter at the business level for change management. The support of renowned institutions such as the World Health Organization and the European Commission demonstrates the importance and urgency of implementing PBM programs, setting guidelines at an international level and supporting the adoption of effective strategies in the management of blood transfusion at a national and institutional level. In Spain, we need to have health managers at both the Hospital Management level and the Regional Health Services and/or Ministry of Health that provide the necessary resources for its proper implementation in the health system from primary care to hospital care and also the resources for the timely evaluation of the results.

Perioperative transfusion management in craniotomies: A national survey, a starting point for the evaluation of improvements in health care

OBJECTIVE

To assess the perioperative management of haemostasis and transfusion practices in adult patients undergoing craniotomies.

METHOD

Online questionnaire addressed to Spanish anaesthesiologists and promoted by the Neurosciences and Haemostasis, Transfusion Medicine and Fluid Therapy Sections of SEDAR. The questionnaire was sent by email and social media, and was active between June and October 2022.

RESULTS

We obtained 155 responses from 67 centres; 59.4% perform >100 craniotomies per year. 61.7% were regularly involved in neuroanaesthesiology. Only 21.9% of respondents had pre-anaesthesia assessment performed by a member of that section, and in most of them (83.0%) the assessment was performed ≤3 weeks in advance. Of the respondents with Patient Blood Management programmes, 58.2% had no specific protocols for craniotomies. 90.3% reported that haemoconcentrates are systematically reserved. A lower platelet limit of 100,000/µL is considered acceptable by 76.8%. 99.4% of respondents discontinued antiplatelet medication based on half-life. Only 23.9% respondents routinely discontinued non-steroidal anti-inflammatory drugs. The transfusion threshold for haemoglobin during surgical bleeding was <10 g/dL in 18.7%, <9 g/dL in 38.1%, <8 g/dL in 38.7% and <7 g/dL in 4.5%.

CONCLUSIONS

Preoperative anaemia screening and treatment programmes are not implemented and blood product reserves are systematised in patients scheduled for craniotomy. Anti-aggregation therapy is discontinued according to the half-life of the drug without checking platelet functionality.

Central/mixed venous oxygen saturation and lactate levels might be of limited use as physiologic transfusion triggers in cardiac surgery: Results of a retrospective analysis

BACKGROUND

Current guidelines differ in their recommendations regarding the use of physiologic transfusion triggers to guide transfusion practice. Data on the interaction between haemoglobin (Hb) and physiologic transfusion triggers, or their response to packed red blood cell (pRBC) transfusions are limited.

OBJECTIVES

This study aimed to evaluate the interactions between Hb, mixed/central venous oxygen saturation (SvO2) and lactate levels as well as their changes (ΔSvO2, Δlactate) in response to pRBC transfusion in cardiac surgery patients.

DESIGN

Retrospective exploratory data analysis.

SETTING

A 22-bed intensive care unit (ICU) at a single tertiary academic centre and university hospital in Austria.

PATIENTS

Adult (age ≥ 18 years) patients who underwent cardiac surgery.

MAIN OUTCOME MEASURES

Pearson correlation coefficients (r) and coefficients of determination (r2) between Hb, mixed/central venous oxygen saturation (SvO2), and lactate levels. Pearson correlation coefficients (r) and coefficients of determination (r2) between ΔSvO2, Δlactate and pretransfusion Hb.

RESULTS

A total of 5025 cardiac surgery patients, in whom 20 542 blood gas analyses were performed, were included in the final analysis. Correlations between Hb levels and SvO2 (r2 = 0.026, P < 0.001) and between Hb and lactate levels (r2 = 0.001, P < 0.001) were statistically significant but weak overall. No correlations were found between ΔSvO2 (r2 = 0.002, P = 0.13) or Δlactate (r2 = 0.003, P = 0.087) and pretransfusion Hb levels.

CONCLUSIONS

Hb, SvO2 and lactate levels were only weakly correlated with each other, and changes in SvO2 and lactate levels in response to pRBC transfusion did not correlate with pretransfusion Hb. Our findings question the usefulness of SvO2 and lactate levels as physiologic transfusion triggers to guide transfusion practice in cardiac surgery patients.

TRIAL REGISTRATION

Johannes Kepler University Ethics Committee Study Reference Number 1063/2023.

Perioperative assessment and management of frailty in elderly patients: a national survey of Italian anesthesiologists

BACKGROUND

The prevalence of frailty is increasing as the global population continues to age. Frailty is associated with poor perioperative outcomes including increased morbidity and mortality. The purpose of this study is to examine current practices and perspectives of anesthesiogists in Italy on the provision of care for elderly surgical patients with frailty.

METHODS

We conducted a national survey. Data were collected via an online questionnaire distributed by the Italian Society of Anaesthesia, Analgesia, Resuscitation and Intensive Care (SIAARTI). Responses were collected over 24 weeks between October 2022 and March 2023.

RESULTS

Seven-hundred thirteen anesthetists completed the survey. A total of 39.8% (277) of respondents were working in university hospitals. Frailty scoring was routinely performed in 51.8% of care settings. Only 26.3% of organizations surveyed had a dedicated pathway for perioperative management of frail elderly patients. The most common method for frailty assessment was the subjective assessment by the anesthesiologist (58.3%). More than half of the participants reported the use of ERAS items in most cases. Almost half of respondents reported the use of postoperative screening tools for delirium (45% of respondents).

DISCUSSION

While these results point to the resistance to clinical implementation of frailty assessment, they also highlight the perceived need for careful management. This can help in identifying elderly patients who may require targeted perioperative management and in ensuring the preservation of cognitive and functional status.

A Modified Viscoelastic Point-of-Care Method for Rapid Quantitative Detection of Enoxaparin: A Single-Centre Observational Study

Background: Laboratory monitoring of the effect of low-molecular-weight heparins (LMWHs) is generally not necessary. However, prompt evaluation of heparin inhibitory effects (i.e., anti-Xa activity) is important in cases of life-threatening bleeding, need for urgent surgery or acute thromboembolism under LMWH treatment. We aimed to establish a simple and reliable point-of-care method for the detection of enoxaparin. Methods: Eighty patients under enoxaparin therapy and ten healthy volunteers without any anticoagulant treatment were enrolled. Simultaneous measurements of anti-Xa activity using the chromogenic method and clotting times in the absence and presence of polybrene using viscoelastometric assays containing Russell's viper venom (RVV-test) were performed on the ClotPro device. Results: Among the measured and derived RVV-test parameters, the ratio of the RVV clotting times (RVV CT) detected in the absence and presence of polybrene showed the best statistically significant correlation with anti-Xa activity (r = 0.774, p < 0.001). Based on ROC analysis, we designated RVV CT ratios of 1.02, 1.23 and 1.6 as the best cut-off values for separating anti-Xa ranges below and above 0.3 and 0.6 IU/mL, respectively. If the RVV CT ratio is below or above 1.23, the anti-Xa activity is suggested to be below 0.6 IU/mL or above 0.3 IU/mL with high certainty, respectively. Further differentiation is possible if the RVV CT ratio is measured below 1.02 or above 1.6. In these cases, the measured anti-Xa values are below 0.3 IU/mL or above 0.6 IU/mL, respectively, with high probability and good predictive values. Conclusions: Our method can provide semiquantitative information on the effect of enoxaparin and the expected anti-Xa activity within 10 min in real clinical situations.

A high HEMSTOP bleeding score is a major independent risk factor for postpartum hemorrhage: a prospective cohort study

BACKGROUND

Postpartum hemorrhage (PPH) is a common yet potentially serious complication of delivery. Recently, the HEMSTOP bleeding score has emerged as a tool for detecting preoperative inherited bleeding disorders. Our objective is to investigate its relevance within the obstetrical context for predicting PPH occurrences among unselected pregnant women.

METHODS

Prospective cohort study conducted in a tertiary maternity hospital between 2014 and 2016 including women without any known bleeding disorder nor antithrombotic therapy who completed the HEMSTOP questionnaire before delivery. Primary outcome was primary PPH ≥ 500 mL following delivery. We studied the bleeding score ranging from zero to seven both as a continuous and an ordinal variable. We used multivariable analysis with adjustment on PPH risk factors. We also estimated the measures of the bleeding score prognostic accuracy.

RESULTS

PPH occurred in 116 of 2536 women (4.6%). Elevated bleeding scores were associated with increased PPH risk (adjusted RR = 1.58; 95% CI, 1.23 to 2.02; P < 0.001 for a continuous score) demonstrating a progressive rise in risk alongside score escalation (adjusted RR = 1.58; 95% CI, 1.01 to 2.46 for a score of one, adjusted RR = 2.11, 95% CI 0.86 to 5.20 for a score of two and adjusted RR = 7.20, 95% CI 2.54 to 20.41 for a score of three compared with a score of zero; P < 0.001). The area under the curve for the bleeding score accuracy in predicting PPH was 0.56 [95% CI 0.52 to 0.61].

CONCLUSIONS

The HEMSTOP bleeding score is weakly predictive of PPH. Women scoring ≥ three are at high risk of PPH.

Resonant acoustic rheometry for assessing plasma coagulation in bleeding patients

Disordered hemostasis associated with life-threatening hemorrhage commonly afflicts patients in the emergency department, critical care unit, and perioperative settings. Rapid and sensitive hemostasis phenotyping is needed to guide administration of blood components and hemostatic adjuncts to reverse aberrant hemostasis. Here, we report the use of resonant acoustic rheometry (RAR), a technique that quantifies the viscoelastic properties of soft biomaterials, for assessing plasma coagulation in a cohort of 38 bleeding patients admitted to the hospital. RAR captured the dynamic characteristics of plasma coagulation that were dependent on coagulation activators or reagent conditions. RAR coagulation parameters correlated with TEG reaction time and TEG functional fibrinogen, especially when stratified by comorbidities. A quadratic classifier trained on selective RAR parameters predicted transfusion of fresh frozen plasma and cryoprecipitate with modest to high overall accuracy. While these results demonstrate the feasibility of RAR for plasma coagulation and utility of a machine learning model, the relative small number of patients, especially the small number of patients who received transfusion, is a limitation of this study. Further studies are need to test a larger number of patients to further validate the capability of RAR as a cost-effective and sensitive hemostasis assay to obtain quantitative data to guide clinical-decision making in managing severely hemorrhaging patients.

Prognostic models for prediction of perioperative allogeneic red blood cell transfusion in adult cardiac surgery: A systematic review and meta-analysis

OBJECTIVES

Identifying cardiac surgical patients at risk of requiring red blood cell (RBC) transfusion is crucial for optimizing their outcome. We critically appraised prognostic models preoperatively predicting perioperative exposure to RBC transfusion in adult cardiac surgery and summarized model performance.

METHODS

Design: Systematic review and meta-analysis.

STUDY ELIGIBILITY CRITERIA

Studies developing and/or externally validating models preoperatively predicting perioperative RBC transfusion in adult cardiac surgery. Information sources MEDLINE, CENTRAL & CDSR, Embase, Transfusion Evidence Library, Web of Science, Scopus, ClinicalTrials.gov, and WHO ICTRP. Risk of bias and applicability: Quality of reporting was assessed with the Transparent Reporting of studies on prediction models for Individual Prognosis or Diagnosis adherence form, and risk of bias and applicability with the Prediction model Risk of Bias ASsessment Tool.

SYNTHESIS METHODS

Random-effects meta-analyses of concordance-statistics and total observed:expected ratios for models externally validated ≥5 times.

RESULTS

Nine model development, and 27 external validation studies were included. The average TRIPOD adherence score was 66.4% (range 44.1%-85.2%). All studies but 1 were rated high risk of bias. For TRUST and TRACK, the only models externally validated ≥5 times, summary c-statistics were 0.74 (95% CI: 0.65-0.84; 6 contributing studies) and 0.72 (95% CI: 0.68-0.75; 5 contributing studies) respectively, and summary total observed:expected ratios were 0.86 (95% CI: 0.71-1.05; 5 contributing studies) and 0.94 (95% CI: 0.74-1.19; 5 contributing studies), respectively. Considerable heterogeneity was observed in all meta-analyses.

DISCUSSION

Future high quality external validation and model updating studies which strictly adhere to reporting guidelines, are warranted.

Guidance-Based Appropriateness of Hemostasis Testing in the Acute Setting

In this review, we aim to highlight the extent of inappropriate hemostasis testing and provide practical guidance on how to prevent it. We will focus on the acute setting, including but not limited to the emergency department and intensive care unit. To this end, we will first discuss the significance of inappropriateness, in the general context of laboratory medicine. This includes acknowledging the importance of the phenomenon and attempting to define it. Next, we describe the harmful consequences of inappropriate testing. Finally, we focus on the inappropriate use of hemostasis testing in the acute setting. The second section describes how interventions-in particular, the implementation of guidance for testing-can efficiently reduce inappropriateness. In the third section, we summarize the available recommendations for rational use of hemostasis testing (platelet count, activated partial thromboplastin time, prothrombin time/international normalized ratio, fibrinogen, thrombin time, D-dimer, anti-Xa assay, antithrombin, ADAMTS13 activity, antiheparin-PF4 antibodies, viscoelastometric tests, coagulation factors, and platelet function testing), as supported by guidelines, recommendations, and/or expert opinions. Overall, this review is intended to be a toolkit in the effort to promote the appropriate use of hemostasis testing. Hopefully, the new In Vitro Diagnostic Medical Device Regulation (EU) 2017/746 (IVDR) should help in improving the availability of evidence regarding clinical performance of hemostasis assays.

Hypovolaemic phlebotomy in patients undergoing hepatic resection at higher risk of blood loss (PRICE-2): a randomised controlled trial

BACKGROUND

Blood loss and subsequent red blood cell transfusions are common in liver surgery. Hypovolaemic phlebotomy is associated with decreased red blood cell transfusion in observational studies. This trial aimed to investigate whether hypovolaemic phlebotomy is superior to usual care in reducing red blood cell transfusions in patients undergoing liver resection.

METHODS

PRICE-2 was a multicentre, single-blind, superiority randomised controlled trial. Patients at a higher risk of blood loss undergoing liver resection for any indication at four Canadian academic tertiary-care hospitals were randomised to receive hypovolaemic phlebotomy or usual care. Hypovolaemic phlebotomy consisted of the removal of 7-10 mL/kg of whole blood, without volume replacement, before liver transection. Patients were randomised centrally using permuted blocks of randomly variable length, stratified by centre. The randomisation sequence was computer-generated by an independent statistician. Surgeons, patients, and outcome assessors were masked to treatment allocation. The primary outcome was perioperative red blood cell transfusion to 30 days post-randomisation, analysed in all randomly assigned patients who underwent liver resection. PRICE-2 trial was registered with ClinicalTrials.gov (NCT03651154) and is completed.

FINDINGS

Between Oct 1, 2018, and Jan 13, 2023, 486 individuals were randomly assigned to receive hypovolaemic phlebotomy (n=245) or usual care (n=241). 22 individuals in the hypovolaemic phlebotomy group and 18 in the usual care group did not undergo liver resection and were thus excluded from the primary analysis population. 223 patients were included in the hypovolaemic phlebotomy group (mean age 61·4 years [SD 13·0]; 137 [61%] men) and 223 in the control group (62·1 years [12·1]; 114 [51%]). 17 (8%) of 223 patients allocated to hypovolaemic phlebotomy and 36 (16%) of 223 patients allocated to usual care had a perioperative red blood cell transfusion by 30 days (difference -8·8 percentage points [95% CI -14·8 to -2·8]; adjusted risk ratio [aRR] 0·47 [95% CI 0·27 to 0·82]). Severe complications to 30 days occurred in 37 (17%) patients allocated to hypovolaemic phlebotomy and 36 (16%) allocated to usual care (aRR 1·06 [95% CI 0·70-1·61]). Overall complications to 30 days occurred in 135 (61%) of 223 patients allocated to hypovolaemic phlebotomy and 116 (52%) of 223 patients allocated to usual care (1·08 [0·92-1·25]). There was no postoperative mortality to 90 days.

INTERPRETATION

In patients undergoing liver resection, hypovolaemic phlebotomy reduced perioperative red blood cell transfusion and improved operative conditions, with no statistically significant increase in the incidence of complications compared with usual care. Hypovolaemic phlebotomy should be considered for routine use in patients undergoing liver resection at higher risk of bleeding.

FUNDING

Canadian Institutes of Health Research (PJT-156108).

Major Bleeding in the Emergency Department: A Practical Guide for Optimal Management

Major bleeding is a life-threatening condition with high morbidity and mortality. Trauma, gastrointestinal bleeding, haemoptysis, intracranial haemorrhage or other causes of bleeding represent major concerns in the Emergency Department (ED), especially when complicated by haemodynamic instability. Severity and source of bleeding, comorbidities, and prior use of anticoagulants are pivotal factors affecting both the clinical status and the patients' differential response to haemorrhage. Thus, risk stratification is fundamental in the initial assessment of patients with bleeding. Aggressive resuscitation is the principal step for achieving haemodynamic stabilization of the patient, which will further allow appropriate interventions to be made for the definite control of bleeding. Overall management of major bleeding in the ED should follow a holistic individualized approach which includes haemodynamic stabilization, repletion of volume and blood loss, and reversal of coagulopathy and identification of the source of bleeding. The aim of the present practical guide is to provide an update on recent epidemiological data about the most common etiologies of bleeding and summarize the latest evidence regarding the bundles of care for the management of patients with major bleeding of traumatic or non-traumatic etiology in the ED.

Quantra analyzer with the QStat® Cartridge compared with conventional laboratory tests during postpartum hemorrhage: a retrospective cohort study (2021-2023)

BACKGROUND

Point-of-care viscoelastic testing devices are of interest for rapid detection of obstetric coagulopathy in postpartum hemorrhage (PPH). However, there is a lack of data on the assessment of coagulation during PPH with the new Quantra device based on sonic estimation of elasticity via resonance.

METHODS

We conducted a retrospective observational cohort study of 130 obstetric patients with PPH with Quantra QStat assessment. Quantra QStat measurements of clotting time (CT), fibrinogen contribution to clot stiffness (FCS) and platelet contribution to clot stiffness (PCS) were compared with the following paired laboratory tests: aPTT, Clauss fibrinogen (CF), and platelet count. The primary aim was to assess correlations between Quantra-QStat measurements and standard laboratory test during PPH. Secondary aims were to investigate the ability of Quantra QStat to diagnose hypofibrinogenemia, thrombocytopenia or coagulation factor deficiencies.

RESULTS

We analyzed 160 paired Quantra QStat and standard laboratory tests. Quantra-QStat tests correlated with laboratory tests as follows: CT with aPTT ratio (rs = 0.61; P <0.001), PCS with platelet count (rs = 0.75; P <0.001), and FCS with CF (rs = 0.84; P <0.001). FCS predicted a CF ≤2 g/L with an AUC of 0.96 (P <0.0001). The optimal cut-off value was 2 hPa. PCS predicted a platelet count < 80,000/μL with an AUC of 0.94 (P <0.0001). The optimal cut-off value was 11.5 hPa, with a sensitivity of 0.89 and a specificity of 0.88. CT predicted an aPTT ratio >1.2 or >1.5 with an AUC of 0.94 (P <0.001) and 0.92 (P <0.0001). The optimal cut-off values were 127 and 133 seconds.

CONCLUSION

Quantra parameters during PPH provide rapid and reliable detection of blood clotting disorders.

Direct-acting oral anticoagulant removal by intraoperative hemoadsorption in CABG and/or single valve surgery: interim analysis of the International Safe and Timely Antithrombotic Removal (STAR) registry

OBJECTIVE

Patients on direct-acting oral anticoagulants (DOACs) are at high risk of perioperative bleeding complications. Intraoperative hemoadsorption is a novel strategy to reduce perioperative bleeding in patients on DOACs undergoing non-deferable cardiac surgery. The international STAR-registry reports real-world clinical outcomes associated with this application.

METHODS

The hemoadsorption device was incorporated into the cardiopulmonary bypass (CPB) circuit and active for the duration of the pump run. Patients on DOACs undergoing CABG and/or single valve surgery before completing the recommended washout were included. Outcome measurements included bleeding events according to standardized definitions and 24-hour chest-tube-drainage (CTD).

RESULTS

A total of 62 patients were included from 7 institutions in Austria, Germany, Sweden, and the UK (mean age 69.9 ± 7.5years, 71% male). Approximately half were on apixaban and the other half was split between rivaroxaban and edoxaban with 21% of patients also on aspirin. Surgery occurred at a median time of 28.9 h since the last DOAC dose with single valve surgery accounting for 2/3 of cases. Mean CPB duration was 118.6 ± 46.4 min. Severe bleeding (UDPB ≥ 3) occurred in 4.8%, and BARC-4 bleeding occurred in 3.2% of the patients. Only one patient (1.6%) required reoperation for bleeding control. The mean 24-hour CTD was 771.3 ± 482.79mL. No device-related adverse events were reported.

CONCLUSIONS

This interim report of the ongoing STAR-registry shows that, in patients on DOAC undergoing non-deferable CABG and/or single valve surgery, the use of intraoperative hemoadsorption is associated with low rates of severe perioperative bleeding complications. Further prospective studies in larger cohorts are needed to validate the efficacy of this method.

CLINICAL REGISTRATION NUMBER

ClinicalTrials.gov identifier: NCT05077124.

Viscoelastic haemostatic assays to guide therapy in elective surgery: an updated systematic review and meta-analysis

BACKGROUND

Patients undergoing major surgery frequently experience major uncontrolled bleeding. The aim of this systematic review and meta-analysis was to evaluate the clinical efficacy of using viscoelastic haemostatic assays to manage peri-operative bleeding in elective surgery.

METHODS

We searched PubMed/MEDLINE and Embase databases for randomised controlled trials according to pre-determined criteria. The primary outcomes were blood product requirements; duration of stay in the operating theatre or ICU; and surgical reintervention rate.

RESULTS

We included 20 randomised controlled trials. The overall risk of bias was low to moderate. Twelve studies used thromboelastography-based transfusion algorithms, while eight used thromboelastometry. Viscoelastic haemostatic assay-guided therapy was associated with a statistically significant reduction in transfusion of red blood cells (standardised mean difference (95%CI) 0.16 (-0.29 to 0.02)), platelets (standardised mean difference (95%CI) -0.33 (-0.56 to -0.10)) and fresh frozen plasma (standardised mean difference (95%CI) -0.64 (-1.01 to -0.28)). There was no evidence of an effect of viscoelastic haemostatic assay-guided therapy on surgical reintervention (relative risk (95%CI) 1.09 (0.70-1.69)). Viscoelastic haemostatic assay-guided therapy was associated with lower blood loss and shorter ICU duration of stay. There was no evidence of any effect on total duration of stay and all-cause mortality.

CONCLUSIONS

Viscoelastic haemostatic assay-guided therapy may reduce peri-operative blood product transfusion requirements and blood loss during major elective surgery, with no discernible effect on patient-centred outcomes. The overall quality of evidence was modest.

Constructing a predictive model for high intraoperative excessive bleeding in patients undergoing posterior lumbar decompression and fusion internal fixation surgery during outpatient visits

OBJECTIVE

1. Construct a risk prediction model to predict the factors of high intraoperative bleeding in patients undergoing posterior lumbar decompression and fusion internal fixation surgery during outpatient visits. 2. Implement pre-hospital blood management for surgery patients, to improve clinical outcomes.

DESIGN & METHODS

We collected patients who underwent two-segment and three-segment posterior lumbar decompression and fusion internal fixation surgery in our hospital from 2016 to 2021. A total of 24 preoperative indicators were analyzed, covering medical history, demographic characteristics, segment, operator and laboratory test results. We used a logistic regression model to optimize the model's feature selection. The predictive model was constructed using the multivariable logistic regression method with all included methods, and a nomogram was created to display the model. Activated partial thromboplastin time, surgeon volume, American Society of Anesthesiologists classification, body mass index, and the number of fusion and fixation lumbar segments were used to construct the predictive model. The predictive model's discrimination, calibration, clinical applicability, and rationality were evaluated.

RESULTS

The predictive model's area under the receiver operating characteristic curve is 0.723, with a 95% confidence interval of (0.685-0.760). The training set's decision curve analysis demonstrates that applying this diagnostic curve will increase the net benefit when the threshold probability is between 5% and 40%.

CONCLUSION

This study developed a novel nomogram with relatively good accuracy to assist clinical doctors in assessing the high intraoperative bleeding risk in patients undergoing posterior lumbar decompression and fusion internal fixation surgery during outpatient visits. By evaluating individual risk, surgeons can develop an individualized treatment plan to reduce the risk of intraoperative bleeding for each patient.

Long-Term Safety of a Four-Factor Prothrombin Complex Concentrate (Kcentra®/Beriplex® P/N): An Updated Pharmacovigilance Review

INTRODUCTION

 Four-factor prothrombin complex concentrate (4F-PCC) is recommended for vitamin K antagonist reversal in patients with major bleeding or in need of surgery. The most important risk associated with the use of 4F-PCC is the occurrence of thromboembolic events (TEEs). In this review, we aim to evaluate the safety profile of a 4F-PCC (Kcentra®/Beriplex® P/N; CSL Behring, Marburg, Germany) by reviewing pharmacovigilance data.

METHODS

 A retrospective analysis of postmarketing pharmacovigilance data of Kcentra®/Beriplex® P/N from February 1996 to April 2022 was performed and complemented by a review of clinical studies published between January 2012 and April 2022.

RESULTS

 A total of 2,321,443 standard infusions of Kcentra®/Beriplex® P/N were administered during the evaluation period. Adverse drug reactions (ADRs) were reported in 614 cases (∼1 per 3,781 standard infusions) and 233 of these cases (37.9%) experienced suspected TEEs related to 4F-PCC (∼1 per 9,963 standard infusions); most of these cases had pre-existing or concomitant conditions likely to be significant risk factors for thrombosis. TEE rates were similar when 4F-PCC was used on-label or off-label for direct oral anticoagulant-associated bleeding. Thirty-six cases (5.9%) reported hypersensitivity type reactions (∼1 per 64,485 standard infusions). No confirmed case of viral transmission related to 4F-PCC use was reported. The published literature also revealed a favorable safety profile of 4F-PCC.

CONCLUSION

 Analysis of postmarketing pharmacovigilance safety reports demonstrated that treatment with 4F-PCC was associated with few ADRs and a low rate of TEEs across multiple indications and settings, thus confirming a positive safety profile of 4F-PCC.

[Transfusion of Fresh Frozen Plasma and Coagulation Factors - Indications, Practice and Complications]

After severe trauma, but also perioperatively, massive bleeding is associated with increased morbidity and mortality. In severely injured patients, hemorrhagic shock remains to be the main cause of death in addition to traumatic brain hemorrhage. In non-cardiac surgery, a surgical bleeding complication increases perioperative morbidity (intensive care length of stay, acute renal failure, infections, thromboembolic complications) by a factor of three to four and mortality by a factor of six. In cardiac surgery, postoperative bleeding requiring surgical revision is associated with a 50% increase in mortality. One possible therapeutic approach is the transfusion of erythrocytes to plasma in a fixed ratio. This practice of untargeted coagulation therapy is mainly used in the USA and some Scandinavian countries. Mortality is significantly worse in the USA than in central Europe, particularly in the case of severe injuries. There is increasing evidence that targeted coagulation therapy with coagulation factor concentrates based on the results of point-of-care coagulation diagnostics is more effective and associated with fewer transfusion- and bleeding-related complications.

Platelet-sparing properties of aprotinin: A scoping review on mechanisms and clinical effects

BACKGROUND

Cardiac surgery involving cardiopulmonary bypass (CPB) is associated with the risk of acquired coagulopathy, including dysregulated fibrinolysis, which can result in life-threatening bleeding complications. Aprotinin, an antifibrinolytic agent, has been recommended for the prevention of these complications. Its effectiveness has been attributed to its ability to nonspecifically inhibit various serine proteases involved in the coagulation and fibrinolysis cascade. Additionally, aprotinin may protect platelets from CPB-induced dysfunction through a platelet-sparing effect, further enhancing its efficacy.

OBJECTIVES

The biochemical pathways underlying aprotinin's platelet-sparing effect remain unclear. Furthermore, it is uncertain to what extent this effect contributes to reducing blood loss and need for transfusion.

DESIGN

A scoping review.

DATA SOURCES

MEDLINE, Embase and Cochrane were searched from inception until 21 December 2023.

ELIGIBILITY CRITERIA

Studies in which a platelet-sparing effect of aprotinin was investigated. These included systematic reviews; experimental, and observational studies describing healthy humans, patients, or animals undergoing any type of surgery; studies in which donated blood was used for in-vitro studies.

RESULTS

Sixty-four studies were deemed eligible, the majority of which observed a platelet-sparing effect, attributing it to the inhibition of platelet aggregation (via protection of glycoprotein (GP) IIb/IIIa receptors), platelet adhesion (by protection of GP Ib receptors), both aggregation and adhesion receptors, proteolysis of protease-activated receptor 1 receptors, platelet activation (by inhibition of plasmin) and platelet activation (by inhibition of thrombin). A dose-dependency of the platelet-sparing effect was investigated in both in-vitro studies and randomised controlled trials, yielding mixed results. No studies have explored the relative contribution of aprotinin's platelet-sparing effect and its antifibrinolytic effect in reducing blood loss and need for transfusion.

CONCLUSIONS

This review elucidated current knowledge on how aprotinin influences platelets and exerts its platelet-sparing effect, while highlighting gaps in the existing literature.

Perioperative paediatric patient blood management: a narrative review

Patient blood management (PBM) encompasses implementing multimodal evidence-based strategies to screen, diagnose, and properly treat anaemia and coagulopathies using goal-directed therapy while minimising bleeding. The aim of PBM is to improve clinical care and patient outcomes while managing patients with potential or ongoing critical anaemia, clinically significant bleeding, and coagulopathies. The focus of PBM is patient-centred rather than transfusion-centred. Multimodal PBM strategies are now recommended by international organisations, including the World Health Organization, as a new standard of care and a proven means to safely and effectively manage anaemia and blood loss while minimising unnecessary blood transfusion. Compared with adult PBM, paediatric PBM is currently not routinely accepted as a standard of care. This is partly because of the paucity of robust data on paediatric patient PBM. Managing paediatric bleeding and blood product transfusion presents unique challenges. Neonates, infants, children, and adolescents each have specific considerations based on age, weight, physiology, and pharmacology. This narrative review covers the latest updates for PBM in paediatric surgical populations including the benefits and principles of paediatric PBM, current expert consensus guidelines, and important universal multimodal therapeutic strategies emphasising clinical management of the anaemic, bleeding, or coagulopathic paediatric patient in the perioperative period. Practical paediatric rules for PBM in the perioperative period are highlighted, with review of specific PBM strategies including treatment of preoperative anaemia, restrictive transfusion thresholds, antifibrinolytic agents, cell salvage, standardised transfusion algorithms, and goal-directed therapy based on point-of-care and viscoelastic testing.

Hemadsorption with CytoSorb®: focus on the latest experiences in cardiac surgery patients

Cardiac surgery patients are potentially exposed to an acute inflammatory host response with a huge release of both pro- and anti-inflammatory cytokines both through intrinsic (e.g., tissue damage, endothelial injury) and extrinsic (e.g., anesthesia, extracorporeal circuits) mechanisms. Current standard of care therapy includes several invasive supportive treatments such as mechanical ventilation, continuous renal replacement therapy, ECMO, and/or cardiopulmonary bypass which may be responsible for an important inflammatory response. The inflammatory cytokine levels and hemodynamic status following these artificial treatments along with the current standard therapy are not always well controlled and may lead to worsened acute clinical conditions with prolonged in-hospital length of stay and increased mortality. In these settings, the administration of hemadsorption therapy with CytoSorb® has been supported by the successful results in several clinical studies as it has shown improvement of both the inflammatory profile and the hemodynamic vascular status of the patients. Therefore, in this narrative review, we summarized and discussed the current scientific literature on the role of CytoSorb® treatment in case of cardiac surgery. According to the current evidences, the raised inflammatory levels and both inotropic and vasopressor requests in cardiac surgery patients need more tailored therapies and, in this contest, the hemadsorption with CytoSorb® could play a pivotal role, especially on heart transplant patients. Furthermore, CytoSorb is currently the only hemadsorption sorbent authorized and efficiently applied for removing anticoagulant agents such as ticagrelor or rivaroxaban in patients undergoing cardiac surgery, to reduce perioperative bleeding complications and should be considered in high-risk patients.

Impact of zero-positive end-expiratory pressure on blood transfusion rates in off-pump coronary artery bypass surgery: a retrospective cohort study

BACKGROUND

Bleeding are common in cardiac surgery, with significant impacts on transfusion-related complications and patient prognosis. This study aimed to determine the differences in perioperative blood loss, transfusion rates, and the incidence of postoperative pulmonary complications (PPCs) with and without the use of positive end-expiratory pressure (PEEP) in patients undergoing off-pump coronary artery bypass graft surgery (OPCAB).

METHODS

This single-center, retrospective study included 106 adult patients undergoing coronary artery bypass surgery without cardiopulmonary bypass from January 2018 to March 2022. The patients were divided into two groups based on intraoperative ventilator settings: the zero-PEEP (ZEEP) group and the PEEP group. The primary outcome was the perioperative transfusion rate from the intraoperative period to postoperative 7 day. The incidence of PPCs was recorded for 1 week post-operatively. Logistic regression analysis was performed for statistical analysis.

RESULTS

The average PEEP in the PEEP group was 4.92 ± 0.42 cmH2O. Multiple regression analysis indicated that lower mean airway pressure during surgery tend to associate with intraoperative lower blood loss. The intraoperative transfusion rates in the ZEEP group were significantly lower than those in the PEEP group (ZEEP:14%, PEEP 38.4%, P = 0.02). Logistic regression analysis revealed that ZEEP (adjusted odds ratio [OR] 0.13, 95% confidence interval [CI] 0.04-0.78) and Society of Thoracic Surgeons(STS) scores (adjusted OR 2.31, 95% CI 1.53-3.49) were significantly associated with a reduced requirement for perioperative transfusions. No significant difference was observed between the two groups in terms of PPCs (p = 0.824). Atelectasis was the most common complication in both groups (ZEEP: 35.7%, PEEP: 40%, P = 0.832).

CONCLUSIONS

ZEEP and STS scores were associated with significantly reduced requirement for perioperative transfusion rates during elective OPCAB surgery. However, ZEEP did not significantly affect the incidence of PPCs.

Cancer-Related Coagulopathy and Perioperative Considerations

Cancer-related coagulation abnormalities are characterized by complex dysregulation of the hemostatic system, predisposing patients to increased risk of thrombotic and hemorrhagic complications and associated increased morbidity and mortality. Advances in anticancer therapies with improved outcomes have led to better survival and older age of patients living with or having survived cancer. There is also a significant increase in the number of patients diagnosed with cancer. All these factors will increase the number of patients presenting for surgical procedures, both cancer-related and noncancer related. It is important for the anesthesiologist to understand the magnitude of cancer-related coagulation derangement, its types, pathophysiology, and clinical presentation, to optimize the perioperative management of this high-risk rapidly growing patient population.

Perioperative considerations in the paediatric patient with congenital and acquired coagulopathy

Neonates, infants, and children undergoing major surgery or with trauma can develop severe coagulopathy perioperatively. Neonates and infants are at highest risk because their haemostatic system is not fully developed and underlying inherited bleeding disorders may not have been diagnosed before surgery. Historically, laboratory coagulation measurements have been used to diagnose and monitor coagulopathies. Contemporary dynamic monitoring strategies are evolving. Viscoelastic testing is increasingly being used to monitor coagulopathy, particularly in procedures with a high risk of bleeding. However, there is a lack of valid age-specific reference values for diagnosis and trigger or target values for appropriate therapeutic management. A promising screening tool of primary haemostasis that may be used to diagnose quantitative and qualitative platelet abnormalities is the in vitro closure time by platelet function analyser. Targeted individualised treatment strategies for haemostatic bleeding arising from inherited or acquired bleeding disorders may include measures such as tranexamic acid, administration of plasma, derived or recombinant factors such as fibrinogen concentrate, or allogeneic blood component transfusions (plasma, platelets, or cryoprecipitate). Herein we review current recommended perioperative guidelines, monitoring strategies, and treatment modalities for the paediatric patient with a coagulopathy. In the absence of data from adequately powered prospective studies, it is recommended that expert consensus be considered until additional research and validation of goal-directed perioperative bleeding management in paediatric patients is available.

Factor Eight Inhibitor Bypass Activity Use in Cardiac Surgery: A Propensity-matched Analysis of Safety Outcomes

BACKGROUND

Bleeding during cardiac surgery may be refractory to standard interventions. Off-label use of factor eight inhibitor bypass activity (FEIBA) has been described to treat such bleeding. However, reports of safety, particularly thromboembolic outcomes, show mixed results, and reported cohorts have been small.

METHODS

Adult patients undergoing cardiac surgery on cardiopulmonary bypass between July 1, 2018, and June 30, 2023, at Stanford Hospital (Stanford, California) were reviewed (n = 3,335). Patients who received FEIBA to treat postcardiopulmonary bypass bleeding were matched with those who did not by propensity scores in a 1:1 ratio using nearest neighbor matching (n = 352 per group). The primary outcome was a composite outcome of thromboembolic complications including any one of deep vein thrombosis, pulmonary embolism, unplanned coronary artery intervention, ischemic stroke, and acute limb ischemia, in the postoperative period. Secondary outcomes included renal failure, reoperation, postoperative transfusion, intensive care unit length of stay, and 30-day mortality.

RESULTS

A total of 704 encounters was included in this propensity-matched analysis. The mean dose of FEIBA administered was 7.3 ± 5.5 U/kg. In propensity-matched multivariate logistic regression models, there was no statistically significant difference in odds ratios for thromboembolic outcomes, intensive care unit length of stay, or mortality. Patients who received more than 750 U FEIBA had an increased odds ratio for acute renal failure (odds ratio, 4.14; 95% CI, 1.61 to 10.36; P < 0.001). In multivariate linear regression, patients receiving FEIBA were transfused more plasma and cryoprecipitate postoperatively. However, only the dose range of 501 to 750 U was associated with an increase in transfusion of erythrocytes (β, 2.73; 95% CI, 0.68 to 4.78; P = 0.009) and platelets (β, 1.74; 95% CI, 0.85 to 2.63; P < 0.001).

CONCLUSIONS

Low-dose FEIBA administration during cardiac surgery does not increase risk of thromboembolic events, intensive care unit length of stay, or mortality in a propensity-matched cohort. Higher doses were associated with increased acute renal failure and postoperative transfusion. Further studies are required to establish the efficacy of activated factor concentrates to treat refractory bleeding during cardiac surgery.

EDITOR’S PERSPECTIVE

Advanced strategies for intensive care management of acute liver failure

Acute liver failure (ALF) is defined as the loss of hepatic function in conjunction with hepatic encephalopathy and coagulopathy. There is histological evidence of profound hepatocyte damage. If it is not aggressively managed, ALF can be fatal within a few days. It is a rare disease, often occurring in patients without prior liver disease. Despite numerous causes, ALF usually presents as acute liver necrosis with a clinical picture that includes cognitive dysfunction, increased aminotransferases, and severe coagulopathy. It is essential to distinguish between ALF and acute-on-chronic liver failure (ACLF). Causes for ALF include paracetamol Acute liver failure (ALF) is characterized by acute liver dysfunction associated with overdose, right heart failure (ischemic liver injury), viral hepatitis (A, B, D and E), autoimmune hepatitis and drug-induced liver injury (including some herbal and nutritional supplements). In developed countries, the prevalence of ALF is 1:1,000,000. Survival rates have increased due to improved ICU management.

The impact of perioperative transfusions on the oncologic outcomes of patients with ovarian cancer: A population-based study

Perioperative blood transfusion in ovarian cancer patients was associated with a 28% increase in all-cause mortality. The negative impact of perioperative blood transfusion extends beyond the immediate postoperative period.

OBJECTIVES

The effect of perioperative blood transfusions on long-term oncologic outcomes of patients with advanced ovarian cancer undergoing cytoreductive surgery remains uncertain. Our study aims to determine the association between perioperative blood transfusion and all-cause mortality in this population.

METHODS

Using province-wide administrative databases, patients with advanced ovarian cancer who underwent surgery between 2007 and 2021 as part of first-line treatment were identified. Perioperative transfusion was defined as any transfusion from date of surgery to discharge from hospital. Multivariable Cox proportional hazards regression models were used to determine if there was an independent association of transfusion with all-cause mortality, accounting significant confounders.

RESULTS

A total of 5891 patients had cytoreductive surgery for advanced ovarian cancer between 2007 and 2021, of which 2898 (49.2%) had interval cytoreductive surgery (ICS) and 2993 (50.8%) had primary cytoreductive surgery (PCS). Perioperative blood transfusion was given to 37.3% of patients (40.5% ICS and 34.2% PCS). On multivariable analysis, there was an increased hazard of all-cause mortality for patients receiving perioperative transfusion compared to those who did not (hazard ratio: 1.28; 95% CI: 1.20-1.37). The association of increased all-cause mortality was observed starting 1 year after surgery, was sustained thereafter, and seen in both ICS and PCS groups.

CONCLUSION

Perioperative blood transfusion after cytoreductive surgery for ovarian cancer is common in Ontario, Canada and was significantly associated with an increase in all-cause mortality. Blood transfusion is a poor prognostic factor, and the negative impact of blood transfusion persists beyond the immediate postoperative period.

The acute phase management of traumatic spinal cord injury (tSCI) with polytrauma: A narrative review

Introduction

Traumatic spinal cord injury (tSCI) is frequently observed in polytrauma patients.

Research question

What is the optimal strategy to manage tSCI in the setting of polytrauma?

Material and methods

This narrative review focuses on: 1) extraspinal damage control surgery and resuscitation, 2) the perioperative protection of the injured spine during emergency surgery, 3) imaging and timing of spinal surgery in polytrauma, 4) early interventions for skin, bowel and bladder, and 5) the multidisciplinary approach to tSCI polytrauma patients.

Results

Damage control resuscitation (DCR) and damage control surgery (DCS), aim to prevent/correct post-traumatic physiological derangements to minimize bleeding until definitive hemostasis is achieved. Spinal protection during emergency surgery is of paramount importance to reduce secondary insults to the injured spine. Imaging, especially magnetic resonance imaging (MRI), is useful for decision-making regarding surgical management of the injured spine. Early decompressive surgery (within 24 h from trauma) is associated with better neurological outcomes. Early consultation with a physical medicine and rehabilitation physician is beneficial to optimize recovery. A close collaboration between different medical specialties involved in the early management of tSCI patients with polytrauma is advisable to improve outcome.

Discussion and conclusion

This narrative review aims to collate basic knowledge regarding acute phase management of tSCI patients in the context of polytrauma. More evidence and data form well-powered studies are necessary in this setting.

Detection of enoxaparin and argatroban by use of the novel viscoelastic coagulometer ClotPro

Owing to the simultaneous increase in the risk of thrombosis and bleeding in critically ill patients, point-of-care-available diagnostic tests to guide parenteral anticoagulation are warranted. We evaluated the detection of enoxaparin and argatroban, two commonly used parenteral anticoagulants, using the novel ClotPro viscoelastic coagulometer. For this experimental in vitro study at a tertiary care academic center, blood samples were drawn from twelve (six female, six male) healthy volunteers without intake of antithrombotic medication and no history of hemostatic disorders. Blood samples were spiked with enoxaparin (IU.ml- 1) and argatroban (µg.ml- 1) at increasing concentrations ranging from 0 to 1. The ClotPro Russell's viper venom (RVV)-test and the ClotPro ecarin (ECA)-test clotting time were performed in parallel with conventional coagulation tests (anti-Xa activity, activated partial thromboplastin time, and diluted thrombin time). We observed a strong correlation between anti-Xa activity and the RVV-test clotting time (r = 0.88 (95% confidence interval (CI) 0.8-0.92; p < 0.001)). Although clotting time cutoff values of 71 and 145 s provided high sensitivity and specificity for detecting anti-Xa activity of ≤ 0.1 and ≥0.6 IU.ml- 1, we found a poor performance at both high and low concentrations. The ECA-test clotting time revealed a very strong correlation with activated partial thromboplastin time (r = 0.96 (95% CI 0.93-0.97; p < 0.001)) and diluted thrombin time (r = 0.97 (95% CI 0.96-0.98; p < 0.001)). The clotting time cutoff values of 86 and 298-431 s provided high sensitivity and specificity for detecting diluted thrombin time values ≤ 0.1 and 0.5-1 µg.ml- 1. Our results suggest that the RVV test is an unreliable method for monitoring enoxaparin treatment, whereas the ECA-test might be an accurate point-of-care alternative for detecting argatroban concentration with potential advantages over standard coagulation tests in terms of point-of-care applicability and turnaround time.

Urgent Reversal of Direct Oral Anticoagulants in Critical and Life-Threatening Bleeding: A Multidisciplinary Expert Consensus

Direct oral anticoagulants (DOACs) are increasingly being used due to their improved efficacy/safety ratio and lower clinical and economic burden when compared to vitamin K antagonists. However, bleeding is still the most frequent complication associated with DOACs, and although rare, bleeding episodes can be life-threatening or critical. The impact of DOAC anticoagulation activity during a bleeding event must be evaluated according to patient clinical assessment, dosage and time from last intake, the presence of comorbidities (especially kidney and liver dysfunction), and, whenever possible, coagulation tests. Unfortunately, DOACs' anticoagulation activity is not easily or usually detectable in routine common coagulation testing. Specific DOAC tests allow for specific drug monitoring, but they are too time consuming, and are usually unavailable in routine emergency practice. If a clinically relevant DOAC plasma concentration is assumed or proven in a severe bleeding scenario, DOAC reversal is needed to restore hemostasis. This experts' consensus provides a narrative review about DOAC reversal and practical life-threatening bleeding management in several scenarios (trauma, intracranial hemorrhage and gastrointestinal bleeding), focusing on the selection of patients to whom specific reversal agents should be given.

Methodological Considerations for Studies Evaluating Bleeding Prediction Using Hemostatic Point-of-Care Tests in Cardiac Surgery

A certain proportion of patients undergoing cardiac surgery may experience bleeding complications that worsen outcomes. Numerous studies have investigated bleeding in cardiac surgery and some evaluate the role of hemostatic point-of-care tests in cardiac surgery patients. The prevalence of excessive bleeding varies in the literature, and such variability stems from the lack of a standardized definition of excessive bleeding. Herein, we report numerous definitions of excessive bleeding and methodological considerations for studies evaluating bleeding using hemostatic point-of-care tests in cardiac surgery patients. We evaluated the role of hemostatic point-of-care devices in contemporary research on bleeding complications and hemostatic management in cardiac surgery. The type of studies (prospective vs. retrospective, interventional vs. observational), patient selection (less complex vs. complex cases), as well as data analysis with comprehensive statistical considerations have also been provided. This article provides a comprehensive insight into the research field of bleeding complications in cardiac surgery and may help readers to better understand methodological flaws and how they influence current evidence.

Return on Investment of Preoperative Anemia Management Programs in Cardiac Surgery: An Advisory From the Society of Cardiovascular Anesthesiologists Clinical Practice Improvement Committee With Endorsement by the Society for the Advancement of Patient Blood Management

Despite multiple recent guidelines recommending the diagnosis and treatment of anemia before elective cardiac surgery, few institutions have formal programs or methods in place to accomplish this. A major limitation is the perceived financial shortfall and the leadership buy-in required to undertake such an initiative. The purpose of this advisory from the Society of Cardiovascular Anesthesiologists (SCA) Clinical Practice Improvement Committee with endorsement by the Society for the Advancement of Patient Blood Management (SABM) is to provide an overview of preoperative anemia management programs with an emphasis on the associated financial implications. This advisory reviews the evidence for preoperative anemia management programs in both cardiac and noncardiac surgery, discusses options for managing preoperative anemia, provides novel financial modeling regarding the implementation of preoperative anemia management programs, and describes implementation challenges, potential solutions, and opportunities for improvement.

Association Between Laboratory Coagulation Parameters and Postpartum Hemorrhage in Preterm and Term Caesarean Section: A Retrospective Analysis

Background: Deranged antepartum laboratory parameters may be risk factors for postpartum hemorrhage (PPH). However, whether this is also valid in women who give birth prematurely is currently unknown. Methods: We performed a retrospective single-center study to assess the role of antepartum hemoglobin, platelet count, fibrinogen, activated partial thromboplastin time, and prothrombin time as risk factors for PPH following caesarean section. We defined PPH as documented blood loss of at least 1 L and/or transfusion of red blood cell concentrates. We stratified the included patients according to gestational age: extremely preterm (gestational age < 28 weeks), very preterm (gestational age between 28 and 32 weeks), late and moderate preterm (gestational age between 32 and 37 weeks), and term (gestational age ≥ 37 weeks). Results: We included 1734 patients, 112 (6%) of whom had PPH. In total, 19 patients (10%) were in the extremely preterm group, 13 patients (10%) were in the very preterm group, 44 patients (9%) were in the late and moderate preterm group, and 36 patients (4%) were in the term group. Hemoglobin predicted PPH in all gestational age groups. Platelet count was associated with PPH in term, but not in preterm patients. Fibrinogen was associated with PPH in late prematurity but not in term patients and not in patients with early or extreme prematurity. Conclusions: Antepartum hemoglobin was the only factor predicting PPH in preterm and term caesarean sections. Platelet count and fibrinogen concentration were associated with PPH in term and late prematurity, respectively, but not in earlier stages of prematurity.

Impact of elevated direct factor Xa inhibitor plasma levels on perioperative blood loss in patients undergoing urgent surgery

INTRODUCTION

Data on the perioperative bleeding risk associated with elevated plasma levels of direct factor Xa inhibitors (FXa inhibitors) are limited. This study examines perioperative red blood cell (RBC) loss in patients undergoing urgent surgery with a residual FXa inhibitor level exceeding 100 mcg/L and without preoperative FXa inhibitor reversal.

METHODS

This retrospective analysis includes data from 32 patients who underwent urgent noncardiac surgery between 2018 and 2022. This study aims to analyze perioperative RBC loss in patients undergoing urgent surgery with a residual FXa inhibitor level exceeding 100 mcg/L and without preoperative FXa inhibitor antidote-based reversal or unspecific treatment with 4-factor prothrombin complex concentrate (PCC). All patients were managed using a watch-and-wait strategy.

RESULTS

The last determination of FXa inhibitor plasma concentration prior to surgery showed a median of 245 mcg/L (IQR 144-345), with a median time interval of 3.8 h (IQR 2.4-7.2) before incision. Median RBC loss during surgery was 49 mL (IQR 0-253), 189 mL (IQR 104-217) until POD1 and 254 mL (IQR 58-265) until POD3. Only one patient required intraoperative treatment with 4-factor-PCC and none required reversal with andexanet alfa. Linear regression models found no significant influence of FXa inhibitor plasma levels on intraoperative RBC loss. Rivaroxaban was associated with higher RBC loss until postoperative Day 1 compared with apixaban. No thromboembolic events were observed.

CONCLUSION

Despite markedly elevated plasma concentrations of residual direct FXa inhibitors, perioperative RBC loss was limited in patients undergoing urgent noncardiac surgery. The intraoperative watch-and-wait strategy with selective intraoperative FXa inhibitor reversal or treatment only when required appears to be an appropriate approach.

Sensitivity and specificity of strategies to identify patients with hemostasis abnormalities leading to an increased risk of bleeding before scheduled intervention: the Hemorisk study

BACKGROUND

Preoperative identification of patients with hemostasis abnormalities leading to an increased bleeding risk is based on routine hemostasis tests: prothrombin time (PT), activated partial thromboplastin time (APTT), and platelet count. Because of their low predictive performance, guidelines recommend replacing them with structured bleeding risk questionnaires, but none is validated in this population.

OBJECTIVES

To assess the diagnostic accuracy of 3 strategies, performed at the preanesthesia visit before scheduled interventions, and to identify patients with hemostasis abnormalities leading to an increased bleeding risk METHODS: A multicenter study was performed in 7 French academic hospitals, involving patients scheduled for surgical intervention, without antiplatelet/anticoagulant treatment. The 3 strategies consisted of 1-a structured screening questionnaire; 2-PT, APTT, and platelet count ordered in selected patients; and 3-systematic PT, APTT, and platelet count. The reference standard comprised von Willebrand factor activity/antigen, factor (F)VIII, FIX, FXI, platelet function analyzer, and, when required, FII, FV, FX, and FVII and hemostasis consultation.

RESULTS

Eighteen (1.2%) of 1484 patients had a hemostasis abnormality leading to an increased bleeding risk according to reference standard. In the overall cohort, sensitivity of the questionnaire-based strategy was 50% (95% CI, 26%-74%; specificity, 87% [95% CI, 85%-88%]); sensitivity was 0% (95% CI, 0%-41%) in men vs 82% (95% CI, 48%-98%) in women. For selective routine tests, sensitivity was 33% (95% CI, 13%-59%) and specificity 97% (95% CI, 96%-98%). Corresponding values for systematic routine tests were 44% (95% CI, 22%-69%) and 93% (95% CI, 91%-94%).

CONCLUSION

Sensitivity was low for all 3 strategies investigated. The structured screening questionnaire had clinically acceptable diagnostic accuracy only in women.

A New Shear-Stress-Based Point-of-Care Technology for Evaluation of the Hemostatic Pattern in Whole Blood

The currently available point-of-care hemostasis tests are burdened by criticisms concerning the use of different activators and inhibitors and the lack of dynamic flow. These operating conditions may constitute an impediment to the determination of the patient's hemostatic condition. Hence, the diffusion of these tests in clinical practice is still limited to specific scenarios. In this work, we present a new method for analyzing the patient's global hemostasis based on the visualization of the main components of the coagulation process and its computerized quantitative image analysis. The automated "Smart Clot" point-of-care system presents a micro-fluidic chamber in which whole blood flows, without the addition of any activator or inhibitor. In this micro-channel, platelet adhesion, activation and aggregation to the type I collagen-coated surface take place (primary hemostasis), leading to the production of endogenous thrombin on the surface of platelet aggregates and the consequent fibrin mesh and thrombus formation (secondary hemostasis). These observations are verified by inhibiting primary hemostasis with the antiplatelet drugs Indomethacin (-70% on platelet aggregation, -60% on fibrin(ogen) formation) and Tirofiban (complete inhibition of platelet aggregation and fibrin(ogen) formation) and secondary hemostasis with the antithrombin drugs Heparin (-70% on platelet aggregation, -80% on fibrin(ogen) formation) and Lepirudin (-80% on platelet aggregation, -90% on fibrin(ogen) formation). Smart Clot, through a single test, provides quantitative results concerning platelet aggregation and fibrin formation and is suitable for undergoing comparative studies with other coagulation point-of-care devices.

Resonant Acoustic Rheometry for Real Time Assessment of Plasma Coagulation in Bleeding Patients

Disordered hemostasis associated with life-threatening hemorrhage commonly afflicts patients in the emergency room, critical care unit, and perioperative settings. Rapid and sensitive hemostasis phenotyping is needed to guide administration of blood components and hemostatic adjuncts to reverse aberrant coagulofibrinolysis. Here, resonant acoustic rheometry (RAR), a technique that quantifies the viscoelastic properties of soft biomaterials, was applied to assess plasma coagulation in a cohort of bleeding patients with concomitant clinical coagulation assays and whole blood thromboelastography (TEG) as part of their routine care. RAR captured the dynamic characteristics of plasma coagulation that were coagulation activators-dependent. RAR coagulation parameters correlated with TEG reaction time and TEG functional fibrinogen, especially when stratified by comorbidities. A quadratic classifier trained on RAR parameters predicted transfusion of fresh frozen plasma and cryoprecipitate with high overall accuracy. These results demonstrate the potential of RAR as a bedside hemostasis assessment to guide transfusion in bleeding patients.