Intravenous lipid emulsion interference in coagulation testing: an ex vivo analysis.

INTRODUCTION: Intravenous lipid emulsion is used in the rescue treatment of certain poisonings. A complication is interference with laboratory analyses. The aim of this study was to determine the impact of intravenous lipid emulsion on routine laboratory analysis of coagulation parameters ex vivo and determine if any of the analytical techniques remain reliable. METHODS: Samples were obtained from 19 healthy volunteers and divided in triplicate. One sample served as a control, and the other two were diluted to simulate the treatment of an average adult with Intralipid® 20 per cent Fresenius Kabi 100 mL (dilution-1) or 500 mL (dilution-2). Coagulation tests performed were prothrombin time, activated prothrombin time, D-dimer concentration and fibrinogen. Coagulation testing was performed by three techniques. Test-1 was performed on a Sysmex CN6000 analyzer. Test-2 was performed with a manual mechanical endpoint method using the semi-automated Stago KC4 Delta. Test-3 involved high-speed centrifugation before repeat testing on the Sysmex CN6000 analyzer. RESULTS: For test-1, only nine (47 per cent) samples in dilution-1 could be analyzed for coagulation tests, and no coagulation tests could be analyzed for dilution-2 because of lipaemia. For test-2 and test-3, all samples could be analyzed, and all results of both testing methods fell within the limits of the laboratory reference range. DISCUSSION: Difficulties in laboratory analysis of patients having received intravenous lipid emulsion are due to multiple factors. Most automated coagulation analyzers use optical measurements, which can be unreliable in the presence of a high intravenous lipid concentration. By altering the lipaemia in the testing solution using high-speed centrifugation or by using manual mechanical endpoint detection, we were able to obtain reliable results. These findings are limited by the use of an ex vivo method and healthy volunteers. CONCLUSIONS: This ex vivo model confirms that Intralipid® interferes with routine coagulation studies. It is important that clinicians are aware and inform their laboratories of its administration.

Quantification of the contribution of individual coagulation factors to haemostasis using a microchip flow chamber system and reconstituted blood from deficient plasma.

BACKGROUND AND OBJECTIVES: Quantifying the contribution of individual coagulation factors to haemostasis may aid our understanding of the haemostatic function in patients with rare coagulation deficiencies (RCDs) and the exploration of suitable treatments. MATERIALS AND METHODS: Reconstituted blood prepared from specific coagulation factor-deficient plasma (factor [F]II; prothrombin, FV, FVII, FVIII, FIX, FX, FXI or FXII) and red blood cell/platelet products were used to simulate the whole blood of patients with RCD. We prepared in vitro treatment models for patients with prothrombin deficiency using coagulation factor agents and fresh frozen plasma. Haemostatic function was measured using a microchip flow chamber system at 600 s-1. RESULTS: The haemostatic function was low, especially in blood samples reconstituted with prothrombin- and FX-deficient plasma. In a plasma transfusion model of prothrombin deficiency, haemostatic function recovered after 10% replacement with normal plasma and reached a plateau at ≧60% replacement. A treatment model of prothrombin deficiency with prothrombin complex concentrates revealed dose-dependent therapeutic effects in the range of 0-50 IU/kg. CONCLUSION: Microchip flow chamber system-based quantification of haemostatic function using reconstituted blood could predict haemostasis and therapeutic effects of treatments in patients with prothrombin deficiency.

The use of Arista AH as a local haemostatic agent in distal splenopancreatectomy: report of two cases.

Bleeding is still one of the most feared intraoperative and postoperative complications that can lead to an increase in morbidity, mortality, length of hospital stay and costs. Nowadays, in addition to accurate surgical techniques, several local haemostatic agents are available and can be used in case of oozing bleeding. Herein, we report our experience with a ready-to-use polysaccharide powder in two patients undergoing distal splenopancreatectomy. Bleeding control was achieved in both cases. No patient showed postoperative bleeding, and no other complications were reported.

Laser-Assisted Lingual Frenectomy: A Case Report.

A lingual frenectomy is a surgical procedure aimed at addressing "tongue-tie" or ankyloglossia, where a strip of tissue restricting tongue movement is removed. Typically, this strip extends from the bottom of the mouth to the underside of the tongue. The procedure, often performed using a diode laser, offers several advantages including simplicity and safety for patients. It can significantly improve speech articulation and eating for individuals with ankyloglossia. This case report highlights the successful treatment of a female patient experiencing speech difficulties with diode laser therapy for tongue-tie.

In vitro analysis of tantalum-containing mesoporous bioactive glass fibres for haemostasis.

Haemorrhage is the leading cause of battlefield deaths and second most common cause for civilian mortality worldwide. Biomaterials-based haemostatic agents are used to aid in bleeding stoppage; mesoporous bioactive glasses (MBGs) are candidates for haemostasis. Previously made Tantalum-containing MBG (Ta-MBG) powders' compositions were fabricated as electrospun fibres for haemostatic applications in the present study. The fibres were fabricated to address the challenges associated with the powder form: difficult to compress without gauze, getting washed away in profuse bleeding, generating dust in the surgical environment, and forming thick callus-difficult to remove for surgeons and painful for patients. Ta-MBGs were based on (80-x)SiO2-15CaO-5P2O5-xTa2O5 mol% compositions with x = 0 (0Ta), 0.5 (0.5Ta), 1 (1Ta), and 5 (5Ta) mol%. The present study details the fibres' in vitro analyses, elucidating their cytotoxic effects, and haemostatic capabilities and relating these observations to fibre chemistry and previously fabricated powders of the same glasses. As expected, when Ta addition is increased at the expense of silica, a new FTIR peak (non-bridging oxygen-silicon, Si-NBO) develops and Si-O-Si peaks become wider. Compared to 0Ta and 1Ta fibres, 0.5Ta show Si-O peaks with reduced intensity. The fibres had a weaker intensity of Si-NBO peaks and release fewer ions than powders. A reduced ion profile provides fibres with a stable matrix for clot formation. The ion release profile for 1Ta and 5Ta fibres was significantly lower than 0Ta and 0.5Ta fibres. Ta-MBGs were not found to be cytotoxic to primary rat fibroblasts using a methyl thiazolyl tetrazolium (MTT) assay. Furthermore, a modified activated partial thromboplastin time assay analysing the fibrin absorbance showed that the absorption increases from physiological clotting < 0Ta < 0.5Ta < 5Ta < commercial haemostat, Surgical SNoWTM, Ethicon, USA < 1Ta. Higher absorption signifies a stronger clot. It is concluded that Ta-MBG fibres can provide stable matrix for clot formation and 1Ta can potentially enhance clotting best among other Ta-MBGs.

EXAMINING VARIABILITY IN THE DIAGNOSIS AND MANAGEMENT OF PEOPLE WITH BLEEDING DISORDERS OF UNKNOWN CAUSE: COMMUNICATION FROM THE ISTH SSC SUBCOMMITTEE ON VON WILLEBRAND FACTOR.

BACKGROUND: Bleeding disorder of unknown cause (BDUC) is characterised by a bleeding phenotype in the setting of normal haemostatic testing. No standardised diagnostic criteria or treatment algorithms exist for people with BDUC. To address the unmet need, the International Society on Thrombosis and Haemostasis von Willebrand Factor Scientific Subcommittee (ISTH VWF SCC) performed a real-world survey, aimed at addressing knowledge gaps, developing consensus pathways and ultimately improving care. OBJECTIVES AND METHODS: We sought to determine current international clinical practices in the investigation, registration, and treatment of people with BDUC through an online structured survey of health care providers (HCPs) who managed patient with bleeding disorders. RESULTS: Two hundred and sixteen respondents from 39 countries were included in the final analysis. The clinical assessment of those with a possible bleeding disorder varied, with only 55% excluding hypermobility but high levels (80%) of bleeding assessment tools (BAT) usage. In haemostatic testing only the prothrombin time (PT) and activated partial thromboplastin time (APTT) tests gained universal support. Tranexamic acid (TXA) was favoured for prophylaxis for minor (71%)/major (59%) surgeries and pregnancy (58%) but advice on the treatment advised if bleeding occurred was heterogeneous. The management of heavy menstrual bleeding (HMB) in women despite combined oral contraceptive pill (COCP) use also proved challenging with HCPs selecting multiple alternative strategies. CONCLUSION: Significant variation exists in the recognition, registration and management of people with BDUC worldwide. This survey emphasises the need for consensus pathways to diagnose and treat BDUC to standardise and improve care for patients internationally.

Ultra-Hydrophobic Gauze Driving Super-Haemostasis.

Controlling bleeding by applying pressing cotton gauze is the most facile treatment in prehospital emergencies. However, the wettable nature of cotton fibers leads to unnecessary blood loss due to excessive blood absorption, inseparable adhesion-induced pain, and pliable to infection. Here, a kind of ultra-hydrophobic haemostatic anti-adhesive gauze whose surface is loaded with polydimethylsiloxane (PDMS) and hydrophobic-modified cellulose nanocrystals (CNCs), achieving a water contact angle of ≈160° is developed. It is demonstrated that the mechanism by which hydrophobic CNCs promote blood clotting is associated with their ability to activate coagulation factors, contributing to fibrin formation, and promoting platelet activation. The blood-restricting effect results from the low surface energy layer formed by PDMS and then the alkyl chains of hydrophobic CNCs are combined. The produced ultra-hydrophobic gauze resists blood flow and diffusion, decreases blood loss, is effortlessly peelable, and minimizes pathogen adhesion. Compared to the commercial cotton gauze, this gauze achieved effective haemostasis and antiadhesion by reducing blood loss by more than 90%, shortening haemostasis time by more than 75%, lowering peeling force by more than 90% and minifying bacterium attachment by more than 95%. This work presents promising applications in terms of prehospital first aid.

Limited value of testing for factor XIII and α2-antiplasmin deficiency in patients with a bleeding disorder of unknown cause.

INTRODUCTION: In patients with an increased bleeding tendency, extensive diagnostic blood testing is often performed. When results of tier 1 assays of primary haemostasis are normal, protocols recommend additional testing to rule out rare disorders including coagulation factor XIII (FXIII) and α2-antiplasmin (α2AP) deficiency. AIM: To evaluate the added diagnostic value of FXIII and α2AP levels in patients with a bleeding disorder of unknown cause (BDUC). METHODS: A retrospective monocentre cohort study between August 2011 and August 2023 was conducted. In all patients with bleeding tendencies and normal diagnostic tests for von Willebrand disease and platelet function, FXIII and α2AP were measured. RESULTS: We included 158 consecutive patients; mean ISTH-BAT scores were 8.2 (SD ± 3.7) in children, 6.2 (SD ± 2.1) in men and 10.6 (SD ± 3.3) in women. Median age was 37 (range 5-79) years, 88.6% of patients were female. Patients displayed median FXIII activity of 111% (IQR = 97-131) and median α2AP activity of 112% (IQR = 103-119). Three (1.9%) patients had FXIII levels < 50%, respectively 43%, 45% and 46%. Corresponding ISTH-BAT scores were 7, 12 and 14. No α2AP levels < 60% was observed. No significant association was found between FXIII levels and ISTH-BAT scores. CONCLUSION: In our cohort of BDUC patients, no clinical relevant FXIII deficiencies were detected; absolute values were well above the 30% cutoff considered adequate for normal haemostasis. No α2AP deficiencies were detected. These data suggest that in BDUC patients, measuring FXIII or AP activity is of limited value.

Effects of PCSK9 on thrombosis and haemostasis in a variety of metabolic states: Lipids and beyond (Review).

Proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors are widely recognised as being able to induce a potent reduction in low­density lipoprotein­cholesterol. An increasing number of studies have suggested that PCSK9 also influences the haemostatic system by altering platelet function and the coagulation cascade. These findings have significant implications for anti­PCSK9 therapy in patients with specific coagulation conditions, including expanded indications, dose adjustments and drug interactions. The present review summarises the changes in PCSK9 levels in individuals with liver diseases, chronic kidney diseases, diabetes mellitus, cancer and other disease states, and discusses their impact on thrombosis and haemostasis. Furthermore, the structure, effects and regulatory mechanisms of PCSK9 on platelets, coagulation factors, inflammatory cells and endothelial cells during coagulation and haemostasis are described.

A novel haemodilution chip mounted on the total thrombus-formation analysis system, a flow chamber system, enables stable analysis of platelet products under low platelet concentration/high shear conditions.

BACKGROUND AND OBJECTIVES: The total thrombus-formation analysis system (T-TAS) can quantitatively analyse the contribution of platelets to haemostasis using reconstituted blood samples. However, it is unsuitable in cases with low platelet counts. We introduced a haemodilution (HD) chip with a shallow chamber depth, adapted to low platelet counts and high shear conditions (1500 s-1). MATERIALS AND METHODS: Blood samples were prepared by mixing red blood cell products, standard human plasma and platelet products; the final platelet count was 50 × 103/µL. Aggregation tests were performed by using the aggregation inducers collagen, adenosine diphosphate (ADP) and ristocetin. Samples with 2-, 4- and 9-day-old platelet products (N = 10) were evaluated. RESULTS: The HD chip enabled the stable analysis of the haemostatic function of all samples at a platelet count of 50 × 103/µL. Haemostatic function was correlated with ADP aggregation (time to 10 kPa [T10]: r = -0.53; area under the curve for 30 min: r = 0.40) and storage period (T10: r = 0.44). CONCLUSION: The HD chip-mounted T-TAS can stably analyse haemostatic function under low platelet counts and high shear conditions; this approach is expected to serve as a bridge to in vivo haemostatic tests with experimental animals.

Protein-based tissue adhesive reduces time to haemostasis in peripheral vascular surgery.

OBJECTIVES: The aim of this study was to evaluate the effectiveness of protein-based tissue adhesive (Bioglue®) in reducing time to haemostasis in patients undergoing peripheral vascular surgery. METHODS: From January to December 2021, 100 consecutive patients from 4 centres have been treated with open peripheral vascular surgery including upper and lower limb interventions. Patients have been allocated in each centre into control with no use of Bioglue® (Group no-Bio, 50 patients) or use of Bioglue® (Group Bio, 50 patients) by a block randomization method 10:10 until the required sample size was reached. Perioperative parameters including time to haemostasis, number of adjunctive stitches, and in-hospital bleeding have been analysed and compared in the two groups by means of mean independent-samples tT -test and Gehan-Breslow-Wilcoxon test. RESULTS: Both groups were homogeneous in terms of demographic data, preoperative risk factors, and preoperative medical therapy except for a higher percentage of active smokers in Group Bio (52% vs. 24%, p = 0.004). Femoral endarterectomy was most common in Group Bio (44% vs. 24%, p = 0.03), whilst the percentage of lower limb vein bypasses was higher in Group no-Bio (50% vs. 36%, p = 0.03). Bovine pericardium was the preferred material in Group Bio (20 cases, 40%), whilst autologous vein is mostly used in Group no-Bio (26 cases, 52%) (p = 0.01). Time to haemostasis was faster in Group Bio (4.4 vs. 9.6 minutes, p < 0.001). The need for adjunctive stitches was higher in Group no-Bio (8 cases, 16%, Group Bio vs. 25 cases, 50%, Group no-Bio; p < 0.001). The overall rate of in-hospital bleeding, including those requiring reintervention, was not different between the two groups (9 cases, 18%, Group Bio vs. 7 cases, 14%, Group no-Bio; p = 0.39). CONCLUSIONS: The protein-based tissue adhesive Bioglue® reduced time to haemostasis and need for adjunctive stitches in peripheral vascular surgery. However, it did not affect the overall rate of perioperative bleedings. Further studies with larger sample sizes are needed to validate these outcomes.

Extracellular vesicles in disorders of hemostasis following traumatic brain injury.

Traumatic brain injury (TBI) is a global health priority. In addition to being the leading cause of trauma related death, TBI can result in long-term disability and loss of health. Disorders of haemostasis are common despite the absence of some of the traditional risk factors for coagulopathy following trauma. Similar to trauma induced coagulopathy, this manifests with a biphasic response consisting of an early hypocoagulable phase and delayed hypercoagulable state. This coagulopathy is clinically significant and associated with increased rates of haemorrhagic expansion, disability and death. The pathophysiology of TBI-induced coagulopathy is complex but there is biologic plausibility and emerging evidence to suggest that extracellular vesicles (EVs) have a role to play. TBI and damage to the blood brain barrier result in release of brain-derived EVs that contain tissue factor and phosphatidylserine on their surface. This provides a platform on which coagulation can occur. Preclinical animal models have shown that an early rapid release of EVs results in overwhelming activation of coagulation resulting in a consumptive coagulopathy. This phenomenon can be attenuated with administration of substances to promote EV clearance and block their effects. Small clinical studies have demonstrated elevated levels of procoagulant EVs in patients with TBI correlating with clinical outcome. EVs represent a promising opportunity for use as minimally invasive biomarkers and potential therapeutic targets for TBI patients. However, additional research is necessary to bridge the gap between their potential and practical application in clinical settings.

[New anticoagulants in 2024: Development of factor XI and XIa inhibitors]. / Les nouveaux anticoagulants en 2024 : développement des inhibiteurs du facteur XI et du XIa.

Thrombosis remains one of the leading causes of death in the world. The history of anticoagulation has evolved considerably from non-specific drugs (i.e., heparins and vitamin K antagonists, VKA) to agents that directly target specific coagulation factors (i.e., argatroban, fondaparinux and direct oral anticoagulants, DOAC). Since the last decade, DOAC are widely used in clinical practice because of their ease to use, their favorable pharmacological profile and the fact that they do not require monitoring. However, despite having a better safety profile than vitamin K antagonist, their bleeding risk is not negligible. New anticoagulants targeting the contact phase of coagulation are currently being developed and could make it possible to prevent the risk of thrombosis without impairing hemostasis. Epidemiological and preclinical data on FXI deficiency make FXI a promising therapeutic target. The aim of this review is to summarize the results of the various clinical trials available that focus on FXI/FXIa inhibition, and to highlight the challenges that this new therapeutic class of anticoagulants will face.

Dental management of people with complex or rare inherited bleeding disorders.

Advances in haematological therapies for people with complex or rare inherited bleeding disorders (IBD) have resulted in them living longer, retaining their natural teeth with greater expectations of function and aesthetics. Dental management strategies need to evolve to meet these challenges. Utilising low level laser diode therapy to reduce pre-operative inflammation to reduce the intraoperative and postoperative burden on haemostasis is described in a case series of 12 patients. For these individuals who previously required further medical management to support haemostasis or experienced such prolonged haemorrhage sufficient to warrant hospital admission, haemostasis was achieved in the dental surgery such that they were able to return home with no further medical intervention or overnight stays. Global inequities in accessing novel treatments for complex or rare IBD necessitates a comprehensive understanding of the local haemostatic agents available to dentists and the most commonly used agents and techniques are described including the use of single tooth anaesthesia (STA). STA is a computerised delivery mechanism that allows routine dental procedures that would previously have required block injections needing factor replacement therapy to be undertaken safely and effectively with no additional haemostatic intervention. The challenges of inhibitors in oral surgery are explained and discussed although more research and evidence is required to establish new treatment protocols. The importance of establishing good dental health in the quality of life of people with complex or rare IBD is highlighted with respect to the dental specific impact that more novel therapies may have on people with IBD.

Efficacy and feasibility of the RADA16 self-assembling peptide, PuraStat® for haemostasis in laparoscopic gynaecological surgery: A pilot study.

Bleeding after laparoscopic gynaecological surgery remains a potential complication. We assessed RADA16 (PuraStat®), a topical self-assembling peptide haemostatic agent, in a pilot study of 46 women undergoing laparoscopic gynaecological surgery. The primary outcome was intraoperative haemostatic efficacy for resection site bleeding. Haemostasis was achieved in all intraoperative bleeding situations (40/40 participants: 100%) with no clinically significant surgical bed bleeding or complications. Mean volume and time required to achieve haemostasis were 6 mL and 14 sec, respectively. This study suggests that PuraStat® is a safe, effective haemostatic agent in laparoscopic gynaecological surgery. Randomised controlled trials are warranted to confirm these findings.

Review article: Upper gastrointestinal bleeding - review of current evidence and implications for management.

BACKGROUND: Acute upper gastrointestinal bleeding (UGIB) is a common emergency requiring hospital-based care. Advances in care across pre-endoscopic, endoscopic and post-endoscopic phases have led to improvements in clinical outcomes. AIMS: To provide a detailed, evidence-based update on major aspects of care across pre-endoscopic, endoscopic and post-endoscopic phases. METHODS: We performed a structured bibliographic database search for each topic. If a recent high-quality meta-analysis was not available, we performed a meta-analysis with random effects methods and odds ratios with 95% confidence intervals. RESULTS: Pre-endoscopic management of UGIB includes risk stratification, a restrictive red blood cell transfusion policy unless the patient has cardiovascular disease, and pharmacologic therapy with erythromycin and a proton pump inhibitor. Patients with cirrhosis should be treated with prophylactic antibiotics and vasoactive medications. Tranexamic acid should not be used. Endoscopic management of UGIB depends on the aetiology. For peptic ulcer disease (PUD) with high-risk stigmata, endoscopic therapy, including over-the-scope clips (OTSCs) and TC-325 powder spray, should be performed. For variceal bleeding, treatment should be customised by severity and anatomic location. Post-endoscopic management includes early enteral feeding for all UGIB patients. For high-risk PUD, PPI should be continued for 72 h, and rebleeding should initially be evaluated with a repeat endoscopy. For variceal bleeding, high-risk patients or those with further bleeding, a transjugular intrahepatic portosystemic shunt can be considered. CONCLUSIONS: Management of acute UGIB should include treatment plans for pre-endoscopic, endoscopic and post-endoscopic phases of care, and customise treatment decisions based on aetiology and severity of bleeding.

Cryogel wound dressings based on natural polysaccharides perfectly adhere to irregular wounds for rapid haemostasis and easy disassembly.

Skin injuries can have unexpected surfaces, leading to uneven wound surfaces and inadequate dressing contact with these irregular surfaces. This can decrease the dressing's haemostatic action and increase the healing period. This study recommends the use of sticky and flexible cryogel coverings to promote faster haemostasis and efficiently handle uneven skin wounds. Alginate cryogels have a fast haemostatic effect and shape flexibility due to their macroporous structure. The material demonstrates potent antibacterial characteristics and enhances skin adherence by adding grafted chitosan with gallic acid. In irregular defect wound models, cryogels can cling closely to uneven damage surfaces due to their amorphous nature. Furthermore, their macroporous structure allows for quick haemostasis by quickly absorbing blood and wound exudate. After giving the dressing a thorough rinse, its adhesive strength reduces and it is simple to remove without causing any damage to the wound. Cryogel demonstrated faster haemostasis than gauze in a wound model on a rat tail, indicating that it has considerable potential for use as a wound dressing in the biomedical area.

Reproducibility and stability of the immature platelet fraction using Sysmex XN-10.

BACKGROUND: The Immature Platelet Fraction (IPF) is an indicator of thrombopoiesis which is a useful parameter in thrombocytopenia. It demonstrates compensatory mechanisms in production of platelets, but currently not implemented in routine clinical practice. The aim of this study was to establish the reproducibility and stability of IPF, for both percentage (%-IPF) and absolute (A-IPF) measurements.Material/methods: A total of 71 samples, of which 45 for reproducibility and 26 for stability analysis, were assayed for full blood count using the Sysmex XN-10 analyser at room temperature (RT:19-25 °C). For reproducibility analysis, IPF measurements were analysed 11 times by different appraisers using the same sample, while for stability analysis, IPF was measured over fourteen hourly-intervals up to 24 h (n = 21) and then separately extended beyond the point of stability to 72 h (n = 5). RESULTS: Reproducibility analysis of %-IPF and A-IPF (n = 45) showed very reliable results, with the range of mean CV% values between 1.25-8.90% and 1.70-9.96%, respectively. On the other hand, overall, stability analysis of %-IPF and A-IPF (n = 21) at RT over 24 h showed reliable results, with pooled mean CV% values of 1.32% and 1.43%, respectively, with no significant difference between %-IPF and A-IPF (p = 0.767 and p = 0.821). All %-IPF and A-IPF values had exceeded the set acceptance criterion of stability (CV% ≥ 10.0%) before 72 h. CONCLUSIONS: Overall, %-IPF and A-IPF reproducibility and storage at RT for 24 h predominantly demonstrates the suitability of their usage for testing on the Sysmex XN-series analysers.