The effects of fructose diphosphate on routine coagulation tests in vitro

To evaluate the effects of fructose diphosphate (FDP) on routine coagulation tests in vitro, we added FDP into the mixed normal plasma to obtain the final concentration of 0, 1, 2, 3, 4, 5, 6, 10, 15, 20, 25, 30 and 35 mg/mL of drug. Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen (FBG) and thrombin time (TT) of samples were analyzed with blood coagulation analyzers from four different manufacturers(Sysmex, Stago, SEKISUI and Werfen) and their corresponding reagents, respectively. Before the experiment, we also observed whether there were significant differences in coagulation test results of different lots of reagents produced by each manufacturer. At the same time as the four routine clotting tests, the Sysmex blood coagulation analyzer and its proprietary analysis software were used to detect the change of maximum platelet aggregation rate in platelet-rich plasma after adding FDP (0, 1, 2, 3, 4, 5 and 6 mg/mL). The results of PT, aPTT and TT showed a FDP (0–35 mg/mL) concentration-dependent increase and a FBG concentration-dependent decrease. The degree of change (increase or decrease) varied depending on the assay system, with PT and aPTT being more affected by the Sysmex blood coagulation testing instrument reagent system and less affected by CEKISUI, TT less affected by CEKISUI and more affected by Stago, and FBG less affected by Stago and more affected by Sysmex. The results of PT, aPTT and TT were statistically positively correlated with their FDP concentrations, while FBG was negatively correlated. The correlation coefficients between FDP and the coagulation testing systems of Sysmex, Stago, Werfen and SEKISUI were 0.975, 0.988, 0.967, 0.986 for PT, and 0.993, 0.989, 0.990 and 0.962 for aPTT, 0.994, 0.960, 0.977 and 0.982 for TT, − 0.990, − 0.983, − 0.989 and − 0.954 for FBG, respectively. Different concentrations of FDP (0, 1, 2, 3, 4, 5 and 6 mg/mL) had different effects on the maximum aggregation rate of platelet induced by the agonists of adenosine diphosphate (ADP, 5 µmol/L), arachidonic acid (Ara, 1 mmol/L), collagen (Col, 2.5 µg/mL) and epinephrine (Epi,10 µmol/L), but the overall downward trend was consistent, that is, with the increase of FDP concentration, the platelet aggregation rate decreased significantly. Our experimental study demonstrated a possible effect of FDP on the assays of coagulation and Platelet aggregation, which may arise because the drug interferes with the coagulation and platelet aggregation detection system, or it may affect our in vivo coagulation system and Platelet aggregation function, the real mechanism of which remains to be further verified and studied.

Factor XI deficiency and delayed hemorrhages after resection of choroid plexus papilloma: illustrative case

BACKGROUND Factor XI deficiency, also known as hemophilia C, is a rare inherited bleeding disorder that may leave routine coagulation parameters within normal range. Depending on the mutation subtype, prolonged activated partial thromboplastin time may occasionally be found. The disease has an autosomal transmission, with an estimated prevalence in the general population of approximately 1 in 1 million. Heterozygosis accounts for partial deficits, but the tendency to bleed is unrelated to the measured activity of factor XI. Diagnosis usually follows unexpected hemorrhages occurring spontaneously or after trauma or surgical procedures. OBSERVATIONS Few cases have been reported in the neurosurgical literature, all occurring spontaneously or after head trauma. Owing to its subtle features, the true incidence of the disease is probably underestimated. The authors report a case of a patient with previously undiagnosed factor XI deficiency who underwent uncomplicated resection of a fourth-ventricle papilloma and experienced delayed, severe hemorrhagic complications. LESSONS The known association between choroid plexus tumors and intracranial bleeding raised differential diagnosis issues. This report may serve to help to investigate delayed hemorrhages after cranial surgery.

Association of circulating proprotein convertase subtilisin/kexin type 9 concentration, prothrombin time and cardiovascular outcomes: a prospective cohort study

Background Proprotein convertase subtilisin/kexin type 9 (PCSK9) is considered to have multiple roles in the development of atherosclerosis, which is recently reported to participate in the thrombotic process. We aimed to examine the relationship between PCSK9 concentration, coagulation indexes and cardiovascular events. Methods A total of 2293 consecutive patients with angina-like chest pain and without lipid-lowering drugs treatment were enrolled and followed up for major adverse cardiovascular events (MACEs). Circulating PCSK9 concentration was determined by ELISA. The routine coagulation tests including activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time were performed. The associations between PCSK9 concentration, routine coagulation indicators and MACEs were analyzed. Results Patients with high PCSK9 levels had lower PT and APTT levels (all p < 0.05). However, PCSK9 concentration was only independently and negatively correlated with PT (β = − 0.115, p < 0.001). During a mean of 38.3 months, 186 (8.1%) MACEs were occurred. Multiple Cox regression analysis indicated high PCSK9 or low PT levels as risk factors related to MACEs. When the prognosis was analyzed by the combination of PCSK9 and PT levels, patients with high PCSK9 and low PT had higher incidence of MACEs compared to those with low PCSK9 and high PT. Conclusions Our study firstly suggested that PCSK9 concentration was negatively correlated with plasma levels of PT. Furthermore, high PCSK9 and low PT were associated with MACEs and the combination of PCSK9 with PT had an addictive effect on predicting cardiovascular outcomes in patients with chest pain, which was useful for further subdivision of cardiovascular risks.

Resolving Interference of Direct Oral Anticoagulants (DOACs) on Routine Coagulation, Thrombophilia, and Lupus Anticoagulant Testing Using Activated Carbon

Background: Direct (anti-IIa and anti-Xa) oral anticoagulants (DOACs) have a significant impact on various coagulation test results. As the correct interpretation of these tests is mandatory to prevent misclassification and subsequent clinical consequences, withholding treatment could be necessary, with the associated risk of thrombosis. Aims: To evaluate the performance of the activated carbon DOAC-Remove (5-Diagnostics, Basel, Switzerland) in extracting DOACs from plasma samples and its effect on various routine and esoteric coagulation test results. Patients, Materials and Methods: Left-over plasmas from patients treated or not with DOAC obtained in the routine laboratory workload were evaluated. Briefly, 0.8 mL of plasma sample was incubated with 1 tablet of the activated carbon for 10 min at room temperature using a rotating shaker. After a 2 min-centrifugation at 2000x g and room temperature, the supernatant was pipetted before being analyzed. Tests were performed before and after such incubation. DOACs were measured using either a specific direct thrombin inhibitor or an anti-Xa assay with specific calibrations. Routine coagulation tests (PT, aPTT, and factor(F)V, FVIII:C, FIX, fibrinogen, and D-dimer) were performed, as well as thrombophilia panel [antithrombin, protein C (PC, chromogenic and clotting assays), PS (free PS antigen and clotting assays)], and lupus anticoagulant (LA) panel [silica clotting time (SCT), and dilute Russell venom clotting time (dRVVT)]. All assays were performed using reagents from Werfen (Bedford, MA, USA) on the ACL TOP 700 analyzer. As the distribution of data was not normal, test results were compared using non-parametric tests. Results: We evaluated a total of 756 plasma samples, obtained from patients treated with dabigatran (n=139, median concentration 129 ng/mL [range:18-905]), rivaroxaban (n=157, median concentration 159 ng/mL [range:19-815]), or apixaban (n=155, median concentration=154 ng/mL (range:11-510), and from 305 patients with various disease states and not on DOAC including 35 patients on coumadin and 32 patients on heparin (UFH: n=18 ; LMWH: n=14). In untreated patients, the DOAC-Remove had no significant impact on test results (n&gt;30 for each parameter), except for D-dimer, free PS and FVIII:C. However, the mean biases, evaluated according to Bland-Altman, were below the accepted limits, and changes would not have had any clinical relevance. In the plasma from patients treated on DOAC, the DOAC-Remove eliminated all the three DOACs, with levels far below the detection limit of the techniques after a 10 min-incubation, leading to a dramatic correction of the DOAC-induced prolongations of PT and APTT, as well as of their lowering effect on FV, FVIII and FIX activities. The same applied to the DOAC-induced elevation of PC and PS anticoagulant activities (clotting assays), and antithrombin activity in the plasma from patients on rivaroxaban and apixaban. DRVVT screen/confirm ratios, which were above the normal ranges in 45% of the patients on dabigatran (n=31), and 78% of the patients on rivaroxaban (n=32), were normalized in most samples after a 10 min-incubation with the carbon and remained positive in only 10% of the patients on dabigatran and 12% of the patients on rivaroxaban. The impact of the DOACs on the SCT screen/confirm ratio was less noticeable with baseline positive test results in only one of the samples from patients on dabigatran (n=31), and in 2 patients on rivaroxaban (n=32). Treatment with the carbon leaded to a correction in the positive sample from patient on dabigatran and in one of the two positive samples from patients on rivaroxaban. Both dRVVT and SCT test results were within the normal range in the plasma from 32 patients on apixaban before and after treatment with the activated carbon. As expected, fibrinogen, PC activity evaluated using a chromogenic assay, free PS antigen concentration, VWF:RCo and VWF:Ag were not affected by any of the 3 DOACs, and test results were not significantly different before and after incubation with the activated carbon. Conclusion: The DOAC-Remove had no effect on test results obtained in the plasma from untreated patients and from patients on traditional anticoagulants. It effectively removed all 3 tested DOACs from the plasma of treated patients, allowing an accurate measurement of routine and esoteric coagulation tests in DOAC treated patients without withholding the treatment. Disclosures No relevant conflicts of interest to declare.

Characteristics of routine coagulationtesting and thromboelastometry in polytrauma patients at admission

Background: polytrauma is one of the emergency surgeries with a high mortality rate. One of the leading causes of death is coagulopathy that is not detected early and treated promptly. Thromboelastometry (ROTEM) is a whole blood assay that evaluates the viscoelastic properties during clot formation and clot lysis. This method can detect coagulopathy rapidly and accurately, thereby improving the management of bleeding after trauma. Objectives: describing and evaluating the correlation between ROTEM parameters and routine coagulation tests in polytrauma patients at admission. Method: 110 patients admitted to the Emergency Department, Viet Duc University Hospital from May 2021 to July 2021 were diagnosed with polytrauma. All patients underwent routine coagulation testing and ROTEM parameters at admission. Result: the average age of patients is 41.4±14.7 years old, men accounts for 77.3%, average ISS score is 24.5±6.3. The proportion of the polytrauma patients with coagulopathy by routine coagulation testing was 50.9%. A significant correlation was found between routine coagulation parameters and ROTEM: between APTT with CFT-INTEM (r=0.65; p<0.01); between PT and CFT-EXTEM (r=0.64; p<0.01); between platelet count and MCF-INTEM (r=0.56; p=0.00) and MCF-EXTEM (r=0.57; p=0.00); between fibrinogen level and MCF-INTEM (r=0.71; p=0.00), MCF-EXTEM (r=0.71; p=0.00), and MCF-FIBTEM (r=0.91; p=0.00). Conclusion: proportion of the polytrauma patients with coagulopathy by routine coagulation testing was 50.9%. A significant correlation was found between routine coagulation parameters and ROTEM

Application of thromboelastography in comparing coagulation difference of rivaroxaban and enoxaparin for thromboprophylaxis after total hip arthroplasty

Purpose: The purpose of this study was to compare the coagulation difference in patients with either rivaroxaban or enoxaparin as thromboprophylaxis after total hip arthroplasty (THA) regarding thromboelastography (TEG) and routine coagulation tests. Patients and methods: Two hundred and twenty-eight patients undergoing primary THA were recruited in this study. They were divided into two groups according to a computer-generated random sequence. Patients in the rivaroxaban group received 10 mg of rivaroxaban orally once daily. Patients in the enoxaparin group received 4000 AxaIU (0.4 mL) of enoxaparin subcutaneously once daily. Rivaroxaban and enoxaparin were started 6–8 h after surgery. The administration of the anticoagulant prophylaxis was lasted for a minimum of 14 days. TEG and routine coagulation tests were performed on the day before the operation and 1 day and 7 days after the operation. Results: No difference was observed in the incidence of deep vein thrombosis (DVT) or pulmonary embolism (PE) between the two groups. There was no significant difference with regard to prothrombin time (PT), activated partial thromboplastin time (PTT), international normalized ratio (INR), and thrombin time (TT) between the two groups. However, while considering TEG, R time of the rivaroxaban group was significantly higher than that of the enoxaparin group ( p = 0.003), whereas the maximum amplitude (MA) ( p = 0.036) value and coagulation index (CI) ( p = 0.002) value were significantly lower than those of the enoxaparin group. Conclusion: With regard to TEG analysis, there was coagulation difference in patients with rivaroxaban and those with enoxaparin as thromboprophylaxis after THA. Under recommended dose of rivaroxaban and enoxaparin, patients undergoing THA were in hypercoagulability on 7days postoperative.

Association between short-term heart rate variability and blood coagulation in patients with breast cancer

The purpose of this study was to investigate the relationship between heart rate variability (HRV), a non-invasive tool for evaluating autonomic function, and routine coagulation indices (RCIs) in patients with breast cancer (BC). Forty-six BC patients were enrolled in this study. Blood biochemistry tests were performed to extract RCIs, including prothrombin time (PT), activated partial thromboplastin time (APTT), and thrombin time (TT). Five-minute electrocardiograms were collected for analysis of HRV parameters (SDNN, RMSSD, LF, HF, LF n.u., HF n.u., LF/HF). Multiple linear regression models examined the relationship of HRV parameters with RCIs. RMSSD, LF n.u., HF n.u., LF/HF were significantly associated with PT. Specifically, the value of PT increased by 0.192 ± 0.091 or 0.231 ± 0.088 s, respectively for each 1 standard deviation (SD) increase in RMSSD or HF n.u.; it increased by 0.230 ± 0.088 or 0.215 ± 0.088 s, respectively for each 1 − SD decrease in LF n.u. or ln (LF/HF) (all P < 0.05). RMSSD was significantly associated with APTT, i.e., the value of APTT increased by 1.032 ± 0.470 s for each 1 − SD increase in RMSSD (P < 0.05). HRV parameters were associated with RCIs in patients with BC. These observations suggest that the autonomic nervous system and coagulation indices in BC patients are linked, potentially explaining the reason that they are both associated with the prognosis.

291 Pre-Operative Venepuncture: An Audit of The Trauma and Orthopaedic Department at The Royal Sussex County Hospital, Brighton

Background NICE recommends that patients undergoing intermediate or minor elective surgery do not need routine coagulation or transfusion blood testing unless they are ASA 3+ or taking anticoagulation mediation, where testing may be considered. Currently there is no guidance for trauma patients. Method We identified all patients that underwent intermediate or minor trauma and orthopaedic surgery within a three-month period from December 2019- February 2020 at the RSCH. We excluded major trauma patients, patients taking anticoagulants and patients with complex admission or past medical history. Computer records were used to identify pre-operative investigations and admission history. Results 843 patients met our inclusion criteria. In total, 92 clotting studies and 200 transfusion samples were taken preoperatively. The majority of tests were for patients undergoing ankle 130/292 (45%) or Tibia/Fibula 54/292 (18%) procedures. This equates to approximately 1168 blood tests per year. Based on the lab cost of £15.97 for a transfusion sample and £18 for a coagulation sample, this is a cost of approximately £19,616 each year on blood testing that is not indicated. Discussion We hope that by presenting these results we will help reduce the unnecessary time and financial burden of routine venipuncture in departments undertaking intermediate and minor surgery.