[Vertebral fractures combined with prolonged activated partial prothrombin time: A case report].

With the development of modern medical standards, autoimmune diseases and their associated successive osteoporosis have received increasing attention in recent years. Patients with autoimmune diseases, due to the characteristics of the disease and the prolonged use of glucocorticoid hormone therapy, may affect the bone formation and bone absorption of the patient, followed by severe successive osteoporosis, thereby increasing the risk of osteoporotic vertebral fractures. Vertebral compression fractures of the spine are common fracture types in patients with osteoporotic fractures. Osteoporosis is a common complication after glucocorticoid therapy in patients with autoimmune diseases. Percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) are minimally invasive operation and are commonly used surgical methods for the treatment of osteoporotic vertebral compression fractures. However, due to the operation of spinal puncture during the operation, there are serious surgical risks such as bone cement leakage, spinal epidural hemorrhage, subdural hemorrhage, and subarachnoid hemorrhage in both PVP and PKP. As a result, it is necessary to evaluate the patient' s body before surgery carefully, especially in the case of blood coagulation. This article reports a case of autoimmune disease patient admitted to Peking University People' s Hospital due to lumbar 4 vertebral compression fracture combined with Sjögren' s syndrome. The patient' s preoperative examination showed that the activated partial thromboplastin time (APTT) was significantly prolonged. After completing the APTT extended screening experiment and lupus anticoagulant factor testing, the multi-disciplinary team (MDT) of Peking University People' s Hospital jointly discussed the conclusion that the patient' s test results were caused by an abnormal self-immunity anti-copulant lupus (LAC). Based on the results of the laboratory examination, the patient was considered to be diagnosed with combined antiphospholipid syndrome (APS). For such patients, compared with the patient' s tendency to bleed, we should pay more attention to the risk of high blood clotting in the lower limbs of the patient, pulmonary clots and so on. With timely anti-coagulation treatment, the patient safely passed the peripheral period and was successfully discharged from the hospital. Therefore, for patients with autoimmune diseases with prolonged APTT in the perioperative period, doctors need to carefully identify the actual cause and carry out targeted treatment in order to minimize the risk of surgical and perioperative complications and bring satisfactory treatment results to the patients.

Clot waveform analysis in acute promyelocytic leukemia.

The aim of this study was to evaluate the activated partial thromboplastin time (APTT) and prothrombin time (PT)-based clot waveform analysis (CWA) in patients diagnosed with acute promyelocytic leukemia (APL). APTT-based and PT-based CWA parameters of patients diagnosed with APL were analyzed and compared with healthy volunteers. Four APTT-CWA parameters were noted, maximum velocity corresponding to the first peak of the first derivative (max1), maximum acceleration corresponding to the first peak of the second derivative (max2) and the corresponding peak times of max1 and max2 (Tmax1, Tmax2). For the PT-CWA, two PT-CWA parameters were noted, maximum velocity (max1') and the corresponding timing (Tmax1'). The results were expressed in medians. Mann-Whitney U test was used to compare the CWA parameters. Correlations were examined using the Spearman correlation test. Tmax1 and Tmax2 were significantly prolonged in patients with APL in comparison with healthy volunteers. Although max1 and max2 were lower in APL patients compared with healthy volunteers, no significant difference was noted. There was a strong and significant correlation between the DIC score and the parameters max1, max2 and max1' and a very strong and significant correlation between fibrinogen levels and max1, max2 and max1'. When comparing DIC patients with hypofibrinogenemia and DIC without hypofibrinogenemia, a significant difference was noted in max1, max2, Tmax1 and Tmax2. The APTT and PT-based CWA analysis is a good tool to evaluate the bleeding tendency in APL, as it offers a novel approach for evaluating global hemostasis, predicting the bleeding risk and delivering improvements to APL patients management.

PDCA cycle management combined with detailed management of postoperative deep vein thrombosis in patients undergoing hip replacement surgery.

OBJECTIVE: This study aimed to analyze and explore the effect of Plan-Do-Check-Act (PDCA) cycle management combined with detailed management on postoperative deep venous thrombosis in patients undergoing hip replacement surgery. PATIENTS AND METHODS: Patients who underwent hip replacement surgery in our hospital between November 2021 and April 2023 were recruited for the study. After screening, patients who met all the inclusion criteria were assessed for eligibility. Finally, 80 adults were enrolled. All patients were assigned into observation and control groups (1:1) according to the sequence of admission, i.e., patients admitted between November 2021 and August 2022 were the control group, and patients admitted between September 2022 and April 2023 were the observation group. RESULTS: The intraoperative blood loss and hospital stay in the observation group were significantly less than those in the control group (p<0.05). After the intervention, the levels of plasma prothrombin time (PT), thrombin time (TT), and thromboplastin time (APTT) in the observation group were higher than those in the control group, and the DD level was lower than that in the control group (p<0.05). There was one patient in the observation group who developed deep venous thrombosis after the operation, and the incidence was 2.50%. The rate was significantly lower than that of the control group (p<0.05). The hip joint function score of the observation group was higher than that of the control group, and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale score was lower than that of the control group (p<0.05). The incidence of adverse reactions in the observation group was significantly lower than that in the control group (p<0.05). CONCLUSIONS: PDCA cycle management plus detailed management in patients with hip replacement surgery yields a favorable clinical outcome, which can effectively prevent postoperative deep vein thrombosis, and improve surgical indicators and postoperative coagulation function. Also, it reduces the incidence of adverse reactions in patients and facilitates recovery. It has a beneficial impact on the prognosis of patients and deserves promotion.

A Comparison between Thromboelastography and Conventional Clotting Tests in Pediatric Patients After Cardiopulmonary Bypass Procedure.

BACKGROUND: The coagulation system is more complicated in younger infants because the hemostatic system is not completely mature before 6 months. There is confusion among pediatricians to choose conventional coagulation tests and thromboelastography (TEG) to evaluate coagulation function for infants in major surgery. This study was undertaken to perform a comparison between the two methods for pediatric patients who underwent cardio-pulmonary bypass (CPB) surgery. METHODS: Infant patients who underwent CPB surgery were divided into two groups - younger group (age < 6 months old, n = 72) and older group (age from 6 months old to 12 years old, n = 76). Prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), and fibrinogen (Fib) of conventional coagulation tests and reaction time (R-time), speed of fibrin building up (ɑ-Angle), clot conformation time (K-time), maximum colt amplitude (MA) of TEG results before and after CPB, as well as increasing or decreasing rate of all the values after CPB, were compared between the two groups. Postoperative transfusion details were summarized. RESULTS: PT, APTT, R-time, and K-time markedly increased (p < 0.05) and Fib, ɑ-Angle, and MA decreased (p < 0.05) after CPB in both groups. The younger group had a much higher rate of postoperative transfusion with suspended red cells (54.17% vs. 17.11%), fresh frozen plasma (29.17% vs. 9.21%), cryoprecipitate (9.72% vs. 1.32%), and apheresis platelet (5.56% vs. 0) than the older group. Increasing rate of R-time and K-time and decreasing rate of ɑ-Angle and MA after CPB in the younger group were significantly higher than that in the older group (p < 0.01), whereas no significant differences were observed in conventional coagulation tests (p > 0.2). CONCLUSIONS: TEG was more sensitive than conventional coagulation tests in response to variation of coagulation function for younger infants after major surgery.

Proper position of single and large (≥5 cm) hepatocellular carcinoma in Barcelona Clinic Liver Cancer classification.

The purpose of this study was to evaluate the proper position of single large hepatocellular carcinoma (HCC) in the Barcelona Clinic Liver Cancer (BCLC) staging system. The data were collected from the nationwide multicentre database of the Korean Liver Cancer Association. Patients with single large (≥5 cm) HCC were separated from BCLC stage A patients and designated as Group X. The remaining BCLC stage A and stage B patients were classified as Group A and Group B, respectively. The survival outcomes of propensity score-matched groups were compared. Among the 3965 randomly selected patients, the number of patients in Group X, Group A, and Group B was 414, 2787, and 760, respectively. TriMatch analysis allowed us to obtain 116 well-balanced triplets. The 1-, 3-, and 5-year overall survival rates in Group X were worse than in Group A (91%, 71%, and 48% vs 90%, 78%, and 64%, respectively; P < .000). However, the rates were not different compared with those in Group B (91%, 71%, and 48% vs 90%, 69%, and 48%, respectively; P < .09). In multivariate analysis, Group X, Group B, age over 60 years, prothrombin time-international normalized ratio, and creatinine level were independent predictors of worse overall survival. Our findings suggest that Group X should be relocated to BCLC stage B rather than BCLC stage A.

Development of a machine learning model to predict intraoperative transfusion and guide type and screen ordering.

STUDY OBJECTIVE: To develop an algorithm to predict intraoperative Red Blood Cell (RBC) transfusion from preoperative variables contained in the electronic medical record of our institution, with the goal of guiding type and screen ordering. DESIGN: Machine Learning model development on retrospective single-center hospital data. SETTING: Preoperative period and operating room. PATIENTS: The study included patients ≥18 years old who underwent surgery during 2019-2022 and excluded those who refused transfusion, underwent emergency surgery, or surgery for organ donation after cardiac or brain death. INTERVENTION: Prediction of intraoperative transfusion vs. no intraoperative transfusion. MEASUREMENTS: The outcome variable was intraoperative transfusion of RBCs. Predictive variables were surgery, surgeon, anesthesiologist, age, sex, body mass index, race or ethnicity, preoperative hemoglobin (g/dL), partial thromboplastin time (s), platelet count x 109 per liter, and prothrombin time. We compared the performances of seven machine learning algorithms. After training and optimization on the 2019-2021 dataset, model thresholds were set to the current institutional performance level of sensitivity (93%). To qualify for comparison, models had to maintain clinically relevant sensitivity (>90%) when predicting on 2022 data; overall accuracy was the comparative metric. MAIN RESULTS: Out of 100,813 cases that met study criteria from 2019 to 2021, intraoperative transfusion occurred in 5488 (5.4%) of cases. The LightGBM model was the highest performing algorithm in external temporal validity experiments, with overall accuracy of (76.1%) [95% confidence interval (CI), 75.6-76.5], while maintaining clinically relevant sensitivity of (91.2%) [95% CI, 89.8-92.5]. If type and screens were ordered based upon the LightGBM model, the predicted type and screen to transfusion ratio would improve from 8.4 to 5.1. CONCLUSIONS: Machine learning approaches are feasible in predicting intraoperative transfusion from preoperative variables and may improve preoperative type and screen ordering practices when incorporated into the electronic health record.

Isolated Prolongation of Activated Partial Thromboplastin Time: Not Just Bleeding Risk!

Activated partial thromboplastin time (aPTT) is a fundamental screening test for coagulation disturbances. An increased aPTT ratio is quite common in clinical practice. How the detection of prolonged activated aPTT with a normal prothrombin time is interpreted is therefore very important. In daily practice, the detection of this abnormality often leads to delayed surgery and emotional stress for patients and their families and may be associated with increased costs due to re-testing and coagulation factor assessment. An isolated, prolonged aPTT is seen in (a) patients with congenital or acquired deficiencies of specific coagulation factors, (b) patients receiving treatment with anticoagulants, mainly heparin, and (c) individuals/patients with circulating anticoagulants. We summarize here what may cause an isolated prolonged aPTT and evaluate the preanalytical interferences. The identification of the cause of an isolated prolonged aPTT is of the utmost importance in ensuring the correct diagnostic workup and therapeutic choices.

Clot Waveform Analysis for Hemostatic Abnormalities.

Clot waveform analysis (CWA) observes changes in transparency in a plasma sample based on clotting tests such as activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). Evidence indicates that not only an abnormal waveform but also peak times and heights in derivative curves of CWA are useful for the evaluation of hemostatic abnormalities. Modified CWA, including the PT with APTT reagent, dilute PT (small amount of tissue factor [TF]-induced clotting factor IX [FIX] activation; sTF/FIXa), and dilute TT, has been proposed to evaluate physiological or pathological hemostasis. We review routine and modified CWA and their clinical applications. In CWA-sTF/FIXa, elevated peak heights indicate hypercoagulability in patients with cancer or thrombosis, whereas prolonged peak times indicate hypocoagulability in several conditions, including clotting factor deficiency and thrombocytopenia. CWA-dilute TT reflects the thrombin burst, whereas clot-fibrinolysis waveform analysis reflects both hemostasis and fibrinolysis. The relevance and usefulness of CWA-APTT and modified CWA should be further investigated in various diseases.

Prothrombin Time and International Normalized Ratio as Predictors of Factor VII Coagulation Activity in Pediatric Patients.

BACKGROUND: Factor VII (FVII) deficiency is characterized by normal activated partial thromboplastin time (aPTT) and prolonged prothrombin time (PT) values. It is diagnosed by determining protein level and coagulation activity (FVII:C). FVII:C measurements are expensive and time consuming. OBJECTIVES: To analyze correlations between PT, international normalized ratio (INR), and FVII:C in pediatric patients before otolaryngology surgery and to establish alternative methods for identifying FVII deficiency. METHODS: FVII:C data were collected from 96 patients with normal aPTT and prolonged PT values during preoperative otolaryngology surgery coagulation workup between 2016 and 2020. We compared demographic and clinical parameters using Spearman correlation coefficient and receiver operating characteristic (ROC) curve analysis to determine the accuracy of PT and INR values to predict FVII deficiency. RESULTS: The median values of PT, INR and FVII:C were 13.5 seconds, 1.14, and 67.5%, respectively. In total, 65 participants (67.7%) displayed normal FVII:C compared to 31 (32.3%) with decreased FVII:C. A statistically significant negative correlation was observed between FVII:C and PT values and between FVII:C and INR. Despite statistically significant ROC of 0.653 for PT (P-value = 0.017, 95% confidence interval [95%CI] 0.529-0.776) and 0.669 for INR (P-value = 0.08, 95%CI 0.551-0.788), we were unable to determine an optimal cutoff point to predict FVII:C deficiency with high sensitivity and high specificity. CONCLUSIONS: We could not identify a PT or INR threshold to best predict clinically relevant FVII:C levels. When PT is abnormal, determining FVII:C protein levels is needed for diagnosing FVII deficiency and considering surgical prophylactic treatment.

Patient with End-Stage Liver Disease and Prolonged Prothrombin Time Presents for Placement of a New Dental Implant.

Dentists should consult with the patient's hepatologist to obtain the most recent medical records with liver function tests and a coagulation panel. In the absence of severe liver dysfunction and with good medical management, dentists may proceed with treatment. Isolated prolongation of prothrombin time does not reflect a risk of bleeding and other coagulation parameters should be assessed. Amide local anesthesia can be safely administered and bleeding is controlled by local hemostatic measures and minimizing trauma. Other aspects of dental treatment that may require modification include the adjustment of doses of certain drugs metabolized by the liver.

Association between PT, PT-INR, and in-hospital mortality in critically ill patients with tumors: A retrospective cohort study.

Objectives: Prothrombin time (PT) and PT-INR are independent predictors of mortality in patients with cancer. The PT and PT-INR of cancer patients are independent predictive variables of mortality. However, whether the PT or PT-INR is related to in-hospital mortality in severely ill patients with tumors remains unknown. Design: This was a case-control study based on a multicenter public database. Settings: This study is a secondary analysis of data extracted from 2014 to 2015 from the Electronic Intensive Care Unit Collaborative Research Database. Participants: The data relevant to seriously ill patients with tumors were obtained from 208 hospitals spread throughout the USA. This research included a total of 200,859 participants. After the samples were screened for patients with combination malignancies and prolonged PT-INR or PT, the remaining 1745 and 1764 participants, respectively, were included in the final data analysis. Primary and secondary outcome measures: The key evaluation methodology was the PT count and PT-INR, and the main outcome was the in-hospital mortality rate. Results: After controlling for confounding variables, we found a curvilinear connection between PT-INR and in-hospital mortality (p < 0.001), and the inflection point was 2.5. When PT-INR was less than 2.5, an increase in PT-INR was positively associated with in-hospital mortality (OR 1.62, 95% CI 1.24 to 2.13), whereas when PT-INR was greater than 2.5, in-hospital mortality was relatively stable and higher than the baseline before the inflection point. Similarly, our study indicated that the PT exhibited a curvilinear connection with in-hospital mortality. On the left side of the inflection point (PT <22), a rise in the PT was positively linked with in-hospital mortality (OR 1.08, 95% CI 1.04 to 1.13, p < 0.001). On the right side of the inflection point, the baseline PT was above 22, and the in-hospital mortality was stable and higher than the PT count in the prior range (OR 1.01, 95% CI 0.97 to 1.04, 0.7056). Conclusion: Our findings revealed that there is a curved rather than a linear link between the PT or PT-INR and in-hospital mortality in critically ill cancer patients. When these two laboratory results are below the inflection point, comprehensive therapy should be employed to reduce the count; when these two laboratory results are above the inflection point, every effort should be made to reduce the numerical value to a value below the inflection point.

Coagulation Tests and Bleeding Classification After Cardiopulmonary Bypass: A Prospective Study.

OBJECTIVE: No recent prospective studies have analyzed the accuracy of standard coagulation tests and thromboelastography (TEG) to identify patients with excessive microvascular bleeding following cardiopulmonary bypass (CPB). The aim of this study was to assess the value of coagulation profile tests, as well as TEG, for the classification of microvascular bleeding after CPB. DESIGN: A prospective observational study. SETTING: At a single-center academic hospital. PARTICIPANTS: Patients ≥18 years of age undergoing elective cardiac surgery. INTERVENTIONS: Qualitative assessment of microvascular bleeding post-CPB (surgeon and anesthesiologist consensus) and the association with coagulation profile tests and TEG values. MEASUREMENTS AND MAIN RESULTS: A total of 816 patients were included in the study-358 (44%) bleeders and 458 (56%) nonbleeders. Accuracy, sensitivity, and specificity for the coagulation profile tests and TEG values ranged from 45% to 72%. The predictive utility was similar across tests, with prothrombin time (PT) (62% accuracy, 51% sensitivity, 70% specificity), international normalized ratio (INR) (62% accuracy, 48% sensitivity, 72% specificity), and platelet count (62% accuracy, 62% sensitivity, 61% specificity) displaying the highest performance. Secondary outcomes were worse in bleeders versus nonbleeders, including higher chest tube drainage, total blood loss, transfusion of red blood cells, reoperation rates (p < 0.001, respectively), readmission within 30 days (p = 0.007), and hospital mortality (p = 0.021). CONCLUSIONS: Standard coagulation tests and individual components of TEG in isolation agree poorly with the visual classification of microvascular bleeding after CPB. The PT-INR and platelet count performed best but had low accuracy. Further work is warranted to identify better testing strategies to guide perioperative transfusion decisions in cardiac surgical patients.

Evaluation of Prothrombin Time and Activated Partial Thromboplastin Time in Native and Citrated Whole Blood in Hispaniolan Amazon Parrots (Amazona ventralis) With a Handheld Point-of-Care Analyzer.

Objective assessment of coagulation in birds is difficult, and traditional methods of measuring prothrombin time (PT) and activated partial thromboplastin time (aPTT) with the use of mammalian reagents have not been validated in birds. Avian-specific reagents must be prepared from brain extract and are not practical for clinical use. The objective of this investigation was to determine whether the InSight qLabs point-of-care analyzer (Micropoint Biotechnologies Inc, Guangdong, China) could measure PT and aPTT in Hispaniolan Amazon parrots (Amazona ventralis) in native and citrated whole blood, and whether the values obtained correlated with clinical appearance and basic hematologic and biochemical parameters from the bird. The qLabs analyzer was able to measure aPTT reliably, but not PT. Activated partial thromboplastin time of citrated blood was significantly different from the aPTT measured from native whole blood (P < 0.001). On the basis of this study, the qLabs machine may be used to measure aPTT, but clinical application between avian species requires further research.

Prolonged prothrombin time does not correlate with clinical bleeding symptoms in newly diagnosed paediatric leukaemia patients.

Prolonged prothrombin time (PT) and/or activated partial thromboplastin time (aPTT) are frequently seen in newly diagnosed paediatric leukaemia patients (NDPLP), which can lead to delayed diagnostic and therapeutic procedures due to concern for bleeding. A single-centre retrospective chart review of NDPLP between 2015 and 2018 aged 1-21 years. We analysed 93 NDPLP of whom 33.3% had bleeding symptoms within 30 days of presentation, predominantly mucosal bleeding (80.6%) and petechiae (64.5%). Median laboratory values: white blood cell count 15.7, haemoglobin 8.1, platelets 64, PT 13.2 and a PTT 31. Red blood cells were administered in 41.2%, platelets in 52.9%, fresh frozen plasma in 7.8% and vitamin K in 21.6% of patients. Prolonged PT was found in 54.8% of patients, while aPTT was prolonged in 5.4%. Anaemia and thrombocytopenia did not correlate with prolonged PT ( P  = 0.73 and P  = 0.18, respectively), or prolonged aPTT ( P  = 0.52 and 0.42). Leukocytosis showed significant correlation with elevated PT ( P  < 0.001), but not aPTT ( P  = 0.3). Bleeding symptoms upon presentation did not correlate with prolonged PT ( P  = 0.83), prolonged aPTT ( P  = 1) or anaemia ( P  = 0.06) but had a significant correlation with thrombocytopenia ( P  ≤ 0.0001). Therefore, a prolonged PT in NDPLP may not necessitate the reflexive use of blood product replacement, in the absence of significant bleeding, which is likely related to leukocytosis than to a true coagulopathy.

Efficacy and safety of salvianolate and enoxaparin in the prevention of perioperative deep venous thrombosis in gastrointestinal surgery.

OBJECTIVE: In this study, the efficacy and safety of salvianolate were compared with enoxaparin in the prevention of perioperative deep vein thrombosis in gastrointestinal surgery. METHODS: From October 2017 to September 2019, 563 patients who underwent gastrointestinal surgery were collected. Based on the inclusion and exclusion criteria, 119 patients were divided into two groups: enoxaparin group (n = 65) and salvianolate group (n = 54). Comparisons were made regarding the outcomes: prothrombin time (PT), prothrombin activity (PTA), international normalized ratio (INR), activated partial thromboplastin time (APTT), fibrinogen (FIB), thrombin time (TT), D-dimer level (D-D), platelet count (PLT), hematokrit (HCT), and incidence of deep vein thrombosis (DVT). RESULTS: The main outcomes showed no significance between enoxaparin group and salvianolate group (p > .05). The incidence of DVT in salvianolate group was 1.85%, significantly lower than that in enoxaparin group (12.3%) (p < .05). No serious adverse reactions occurred in the two groups during treatment. CONCLUSION: Compared with enoxaparin, salvianolate has an advantage in the prevention of perioperative thrombosis in gastrointestinal surgery with a lower incidence of DVT.

Preoperative coagulation screening tests in pediatric patients: Clinical relevance and hemorrhagic outcomes of abnormal results.

PURPOSE: Coagulation screening tests in children are still frequently performed in many countries to evaluate bleeding risk. The aim of this study was to assess the management of unexpected prolongations of the activated partial thromboplastin time (APTT) and prothrombine time (PT) in children prior to elective surgery, and the perioperative hemorrhagic outcomes. METHODS: Children with prolonged APTT and/or PT who attended a preoperative anesthesia consultation from January 2013 to December 2018 were included. Patients were grouped according to whether they were referred to a Hematologist or were scheduled to undergo surgery without further investigation. The primary endpoint was to compare perioperative bleeding complications. RESULTS: 1835 children were screened for eligibility. 102 presented abnormal results (5.6%). Of them, 45% were referred to a Hematologist. Significant bleeding disorders were associated with a positive bleeding history, odds ratio of 51 (95% CI 4.8-538.5, P=.0011). No difference in perioperative hemorrhagic outcomes were found between the groups. An additional cost of 181 euros per patient and a preoperative median delay of 43 days was observed in patients referred to Hematology. CONCLUSIONS: Our results suggest that hematology referral has limited value in asymptomatic children with a prolonged APTT and/or PT. Hemorrhagic complications were similar among patients referred and not referred to Hematology. A positive personal or family bleeding history can help identify patients with a higher bleeding risk, thus it should guide the need for coagulation testing and hematology referral. Further efforts should be made to standardize preoperative bleeding assessments tools in children.

Estimating the measurement uncertainties of the international sensitivity index of 12 thromboplastins through Monte Carlo simulation.

BACKGROUND: Measurement uncertainty (MU) estimation has become an important process in clinical laboratories; however, calculating the MUs of the international sensitivity index (ISI) of thromboplastins is difficult because of the complex mathematical calculations required in calibration. Therefore, this study quantifies the MUs of ISIs through the Monte Carlo simulation (MCS), which involves random sampling of numerical values to solve a complex mathematical calculation. METHODS: Eighty blood plasmas and commercially available certified plasmas (ISI Calibrate) were used to assign the ISIs of each thromboplastin. Prothrombin times were measured using reference thromboplastin and 12 commercially available thromboplastins (Coagpia PT-N, PT Rec, ReadiPlasTin, RecombiPlasTin 2G, PT-Fibrinogen, PT-Fibrinogen HS PLUS, Prothrombin Time Assay, Thromboplastin D, Thromborel S, STA-Neoplastine CI Plus, STA-Neoplastine R 15, and STA-NeoPTimal) with two automated coagulation instruments: ACL TOP 750 CTS (ACL TOP; Instrumentation Laboratory, Bedford, MA, USA) and STA Compact (Diagnostica Stago, Asnières-sur-Seine, France). Then, the MUs of each ISI were simulated through MCS. RESULTS: The MUs of ISIs ranged from 9.7 % to 12.1 % and 11.6 % to 12.0 % when blood plasma and ISI Calibrate were used, respectively. For some thromboplastins, the ISI claimed by manufacturers significantly differed from the estimated results. CONCLUSIONS: MCS is adequate to estimate the MUs of ISI. These results would be clinically useful for estimating the MUs of the international normalized ratio in clinical laboratories. However, the claimed ISI significantly differed from the estimated ISI of some thromboplastins. Therefore, manufacturers should provide more accurate information about the ISI value of thromboplastins.

Preoperative Predictive Nomogram Based on Alanine Aminotransferase, Prothrombin Time Activity, and Remnant Liver Proportion (APART Score) to Predict Post-Hepatectomy Liver Failure after Major Hepatectomy.

INTRODUCTION: Post-hepatectomy liver failure (PHLF) is a serious complication associated with major hepatectomies. An accurate prediction of PHLF is necessary to determine the feasibility of major hepatectomy. This study aimed to assess the association between PHLF and preoperative laboratory and computed tomography (CT) findings. METHODS: Medical records of 65 patients who underwent major hepatectomy and preoperative CT were retrospectively reviewed. We evaluated future remnant liver volume evaluation models and remnant liver hemodynamics, which were assessed by arterial enhancement fraction (AEF) by using preoperative CT. Variables, including CT findings, were compared between patients with and without PHLF after major hepatectomy, and the preoperative PHLF-predicting nomogram was constructed using multivariate logistic regression. RESULTS: The PHLF group included 21 patients (32.3%). The AEF was not significantly different between the two groups. In the future remnant liver volume evaluation models, future remnant liver proportion (fRLP) had the highest concordance index (C-index) in the receiver operating characteristic curve analysis (C-index, 0.755). Multivariate analysis of preoperative evaluable factors revealed that alanine aminotransferase levels (p = 0.034), prothrombin time activity (p = 0.021), and fRLP (p = 0.012) were independent predictive factors of PHLF. A nomogram (APART score) was constructed using these three factors, with a receiver operating curve showing a C-index of 0.894. According to the APART score, scores of 51-60 indicated moderate risk (40.0%), and scores over 60 indicated a high risk of PHLF (83.3%) (p < 0.001). DISCUSSION: The APART score may help predict PHLF in patients indicated for major hepatectomies.

Associations among Plasma Concentrations of Edoxaban and M-4, Prothrombin Time, and the SLCO1B1*15 Haplotype in Patients With Nonvalvular Atrial Fibrillation.

INTRODUCTION: The authors aimed to examine the impact of single nucleotide polymorphisms in P-glycoprotein, the hepatic uptake transporter organic anion transporter protein 1B1, cytochrome P450 ( CYP ) 3A5, and carboxylesterase-1 ( CES1 ) on the steady-state dose-adjusted trough concentrations of edoxaban (C Edo /D) and M-4 (C M-4 /D). They also investigated whether C M-4 and C Edo affect prothrombin time (PT). METHODS: The analyses included 152 patients with nonvalvular atrial fibrillation (NVAF) undergoing AF catheter ablation. The CYP3A5*3 ; CES1 c.1168-33A>C, c.257+885T>C; SLCO1B1 c.388A>G, c.521T>C; and ABCB1 c.3435C>T, c.2677G>A/T, c.1236C>T genotypes were determined. RESULTS: Stepwise selection multiple linear regression analyses demonstrated that creatinine clearance (Ccr), concomitant use of amiodarone, and SLCO1B1*15 haplotype status were independent factors influencing C M-4 /D (partial R2 = 0.189, 0.098, 0.067, respectively, all P values < 0.005). Ccr and concomitant use of amiodarone were independent factors influencing C Edo /D (partial R2 = 0.260, 0.117, respectively, both P value < 0.001). C Edo and C M-4 showed a weak correlation with PT (ρ = 0.369 and 0.315, both P values < 0.001). CONCLUSIONS: Although information concerning Ccr, concomitant use of amiodarone, and SLCO1B1*15 haplotype may be useful in assessing the pharmacokinetics of edoxaban, further studies are needed to clarify the requirement of PT monitoring at the trough level for dose adjustment of edoxaban in patients with NVAF.

Comparing modified Lee and White method against 20-minute whole blood clotting test as bedside coagulation screening test in snake envenomation victims

Abstract Background: Twenty-minute whole blood clotting test (20WBCT) and Modified Lee and White (MLW) method are the most routinely employed bedside tests for detecting coagulopathic snake envenomation. Our study compared the diagnostic utility of MLW and 20WBCT for snakebite victims at a tertiary care hospital in Central Kerala, South India. Methods: This single-center study recruited 267 patients admitted with snake bites. 20WBCT and MLW were performed simultaneously at admission along with the measurement of Prothrombin Time (PT). The diagnostic utility of 20WBCT and MLW was determined by comparing the sensitivity (Sn), specificity (Sp), positive and negative predictive values, likelihood ratios, and accuracy at admission with an INR value > 1.4. Results: Out of 267 patients, 20 (7.5%) patients had VICC. Amongst those who had venom-induced consumption coagulopathy (VICC), MLW was prolonged for 17 patients, (Sn 85% 95% confidence interval [CI]: 61.1-96.0) whereas 20WBCT was abnormal for 11 patients (Sn 55%, 95% CI: 32.04-76.17). MLW and 20WBCT were falsely positive for the same patient (Sp 99.6%, 95% CI: 97.4-99.9%). Conclusion: MLW is more sensitive than 20WBCT to detect coagulopathy at the bedside amongst snakebite victims. However, further studies are necessary for standardizing bedside coagulation tests in snakebite cases.