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Wireless sensor nodes remain vulnerable to malicious attacks in hostile environments. Adversarial attacks capturing a few benevolent nodes and creating multiple duplicate identities make the localization process very tricky. Incorrect position estimations often lead to the wrong decision regarding the monitored event. This paper presents a secure localization scheme mitigating such attacks using fuzzy-based anchor mobility control. All nodes periodically broadcast signals over the network using omnidirectional antennas. The anchor each time forms an individual cluster using some neighboring nodes with an Received Signal Strength (RSS ) exceeding a prescribed threshold. The mobility control algorithm keeps the anchor moving along a path that allows cluster formations at two successive anchor positions containing at least the nodes encountered first in the previous case. The current cluster size and the node location with minimal signal strength are two determining factors for the fuzzy controller to explore a new anchor path. The misbehaving nodes are detected and blocked by observing anomalies in node identities within the subsequent two clusters. The anchor contains an adaptive antenna and remains location-aware with a Global Positioning System (GPS) receiver. The anchor determines the Angle of Arrival (AoA ) information of all the signals intercepted in each cluster using such an antenna. Then, the anchor generates and transmits beacon messages to each legitimate node. Upon receipt of two beacon messages, the nodes localize themselves autonomously and switch to power-saving mode. The simulation results corroborate its competence comparable to existing methods for localization accuracy and intrusion detection precision. [ABSTRACT FROM AUTHOR]

Thrombotic thrombocytopenic purpura (TTP) secondary to dengue fever is a very unusual occurrence. Both conditions are fatal and can result in significant mortality and morbidity if left untreated. In this case, we present a young lady who suffered dengue fever followed by microangiopathic anemia, thrombocytopenic purpura, and altered sensorium. Investigations revealed microangiopathic hemolysis; there was no evidence of disseminated intravascular coagulation. As soon as, we diagnosed the patient as having TTP, we treated her with serial plasma exchange therapy, steroids, and monoclonal antibodies such as rituximab. The patient responded very well to the treatment and completely recovered from neurological symptoms and laboratory parameters also normalized. Hence, timely diagnosis and starting appropriate treatment immediately are key factors for successful outcomes. [ABSTRACT FROM AUTHOR]

Background & Objectives: Hyperthrombocytosis may cause acquired thrombosis-related symptoms and fatal vascular complications. Currently, therapeutic platelet reduction (TPR) with medical therapy remains the mainstay of hyperthrombocytosis management. We encounter patients with high platelet counts with requests for TPR. Here, we share our experience of TPR procedures in patients with symptomatic hyperthrombocytosis due to various underlying etiologies. Methods: The study from January 2013 to October 2020 included 36 patients of hyperthrombocytosis who underwent 82 TPR procedures by apheresis technology. Patient details were obtained from the treatment file and all procedures were performed following recommended instructions and protocol. Statistical analysis was done using the SPSS statistical package. Results: The median age of patients was 53 years with mean hemoglobin, platelet count, plateletcrit, and platelet distribution width of 9.9 g/dL, 1711.3 × 106/mL, 0.57%, and 43.4%, respectively. A total of 26 patients had primary thrombocytosis. The mean TPR procedure time, whole blood volume processed, and anticoagulant used were 162 min, 5070 mL, and 430.3 mL, respectively. The mean reduction of platelets in patients who underwent two and three procedures was 72.4% and 82.7%, respectively (P = 0.003). Conclusion: We conclude that TPR is a useful method in reducing platelet count rapidly in hyperthrombocytosis. It relieves patients of acute symptoms and prevents thrombotic events. The decision to perform TPR should be individualized and based on the clinical scenario, degree of thrombocytosis, and risk factors associated with TPR procedures. [ABSTRACT FROM AUTHOR]

Background and Objectives: Passive transfusion of convalescent plasma (CCP) in coronavirus disease 2019 (COVID-19) has proven to be a winning and logistically feasible therapeutic strategy. The efficacy of plasma depends on appropriate donor screening and selection. Ours being a tertiary care hospital with dedicated COVID facility, we obtained prescriptions of CCP from clinicians for the treatment of COVID-19. Here, we discuss the clinical and serological characters of the voluntary donors who altruistically visited the blood center for plasma donation. Methods: The study included 683 voluntary donors who visited the blood center for mandatory eligibility screening to donate plasma. Donor eligibility criteria were applied following established guidelines. Donor details were obtained from blood center records and software. Detailed investigations on blood samples were performed as mandated and discussed. Results: Among 683 donors initially registered 166 (24.3%) were deferred due to various causes The median age of eligible donors was 44 years with a male preponderance. The mean anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG (S/Co) was calculated to be 12.9. An upward trend in anti-SARS-CoV-2 IgG level was observed with increase in fever temperature, disease severity, and symptom-free days (P < 0.05). Conclusion: Donor screening and selection in CCP donation should be performed meticulously to obtain safe and potent plasma products. Based on our findings, we suggest that in addition to optimum anti-SARS-CoV-2 IgG levels, factors such as the severity of disease, fever temperature, and symptom-free days which determine antibody adequacy may be considered while selecting CCP donors. [ABSTRACT FROM AUTHOR]

Background and Objectives: The risk of red blood cell (RBC) alloimmunization is always a concern for multi-transfused patients. Various factors have been found to be associated with alloimmunization. Alloimmunization rates were reported from 4% to 50%, 1.9% to 13% and 1.27% to 13.1% in thalassemic, onco-hematology and renal patients respectively. Transfusion of extended phenotype-matched blood was found to reduce rate of alloimmunization. This study investigated the various risk factors associated with RBC alloimmunization and the impact of transfusing phenotype-matched PRBC to multi-transfused patients. Methods: The retrospective observational study included 4350 multi-transfused patients of hemoglobinopathies, onco-hematological diseases and chronic renal failure (CRF). Pre-transfusion testing that included ABO and Rh(D) typing, antibody screening and crossmatching were performed following departmental standard operating procedure (SOP). Rh (C, c, E, e) and Kell (K) antigen phenotyping of blood donors as well as patients were performed by recommended techniques. Statistical analysis was done using the SPSS statistical package. Results: The mean age of multi-transfused patients was 41.4 years with a female preponderance. A total of 122 alloantibodies with various specificities were found in the 4350 patients (2.8%). Anti-E was the most frequent alloantibody (27.87%) followed by anti-c (11.48%). Frequency of alloimmunization in patients with hemoglobinopathies receiving phenotype-matched blood was 1.89% which was significantly lower than those receiving phenotype-unmatched blood (p=0.0019). Gender, age, splenomegaly status, number of PRBC unit transfused, phenotypematched status, and transfusion duration in years were independent risk factors of alloimmunization. Conclusion: Alloimmunization to red blood antigens challenge the proper management of multi-transfused patients. Based on the present results we suggest considering antibody screening as an important tool of pre-transfusion testing to ensure safe blood transfusion. It will be prudent to adopt a transfusion policy that provides at least the Rh-Kell phenotype-matched blood to minimize red cell alloimmunization among multi-transfused patients. [ABSTRACT FROM AUTHOR]

BACKGROUND: Significant blood loss and requirement of allogenic blood transfusion during or after total knee replacement (TKR) have been reported. Incidence of blood transfusion in TKR is highly variable and depends on several factors. We investigated the blood utilization in patients undergoing TKR in our hospital and depicted the important risk factors that determine the need of allogenic blood transfusion in primary unilateral TKR. MATERIALS AND METHODS: The study included 1241 consecutive patients undergoing primary unilateral total knee arthroplasty. All the surgeries were performed by a single surgical team of orthopedists following standard procedure. Patient and disease details were obtained from patient file and hospital information system. Compatibility test was performed in blood bank before blood reservation following mandatory guidelines. Details of test, blood issue, and blood transfusion were documented in the blood bank. RESULTS: Of 1241 enrolled patients, 1069 (86.2%) were female. The median age of patients was 66 years with mean preoperative hemoglobin of 9.9 g/dL. Allogenic blood transfused was needed in 223 (17.9%) patients. Diabetes mellitus, hypertension, thyroid disorders, and chronic heart diseases were the major comorbid conditions. Risk factors such as gender, American Society of Anesthesiologists score, preoperative hemoglobin, and intraoperative and postoperative blood losses were significantly associated with blood transfusion. CONCLUSION: The risk factors determining blood transfusion in TKR vary between studies, however, all centers should establish standard operating procedures describing the surgical procedure and transfusion support in TKR. In addition, each center may develop specific blood management strategy to rationalize blood transfusion in TKR and overall successful care in TKR. [ABSTRACT FROM AUTHOR]

Background and Objectives: Transfusion of COVID convalescent plasma (CCP) has been found to be a useful and logistically feasible therapeutic strategy in COVID-19. Appropriate guidelines describing donor eligibility criteria, CCP collection and storage, and clinical transfusion of CCP have been described. In this study, we discussed the collection of CCP by plasmapheresis, quality of product obtained, and donor adverse reactions associated with CCP collection. Methods: This observational study included 209 screened eligible donors and 186 procedures of plasmapheresis for the collection of CCP. Donor selection and CCP collection were done as per the guidelines described by regulatory bodies. Statistical analysis was done using the SPSS statistical package. Results: The median age of the eligible donors was 42 years, with a male preponderance. The mean anti-severe acute respiratory syndrome coronavirus 2 immunoglobulin G value (S/Co) was 11.8 in eligible donors. The total mean whole blood volume processed to collect the targeted plasma volume, mean utilization of anticoagulant, and mean time needed to complete the procedure were significantly more in the Spectra Optia cell separator (P < 0.05). Quality of the plasma separated by Trima Accel and Spectra Optia was found to be comparable. A total of 9 (5.1%) donors experienced adverse events during or after plasmapheresis. Conclusion: Plasmapheresis using new-generation automated cell separators has the potential to generate CCP of optimized quality and potency. More emphasis is needed on the quality control of CCP with regard to the establishment of defined quality markers and their allowable limits. Appropriate donor vigilance, donor selection, and equipment management during the procedure may significantly prevent adverse events related to plasmapheresis. [ABSTRACT FROM AUTHOR]

Background and Objectives: Most patients with coronavirus disease-2019 (COVID-19) do not need blood transfusion, and only a subset of critically ill patients requires transfusion. Here, we describe the pattern of blood usage in COVID-19 patients in our hospital with regard to indications, clinical and laboratory evaluations, and blood and blood component transfusions. Methods: This is a retrospective study that included 34 hospitalized transfused patients admitted with clinical features and diagnosis of COVID-19. Demographic, clinical, laboratory, and blood transfusion details were obtained from patient files and blood bank software. Statistical analysis was done using the IBM SPSS statistical package. Results: Among the 419 hospitalized COVID-19 patients, 34 (8.1%) received blood transfusion. Levels of D-dimer, serum ferritin, and interleukin-6 as high as 8545 ng/mL, 8486 ng/mL, and 256 pg/mL, respectively, were observed in few patients. Comorbidity was demonstrated in 91.2% of transfused patients. A total of 6 (17.6%) patients succumbed to disease. Packed red blood cell was the main blood component transfused to COVID-19 patients followed by platelet (PLT) and plasma products. A rise in trend in blood utilization was demonstrated from March to June 2020 with a dip in July 2020. Compared to other months, more patients required PLT concentrates in June 2020. Conclusion: Blood utilization in COVID-19 patients is usually low and does not affect the blood inventory significantly. Most transfused patients have been critically ill, and the trend in blood utilization in COVID-19 patients may be difficult to ascertain. [ABSTRACT FROM AUTHOR]

Lemierre's syndrome is a condition characterised by septic thrombophlebitis of internal jugular vein following an oropharyngeal infection along with septic embolisation to other organs mainly lungs. This report is about a 14-year-old girl who presented with complaint of high-grade fever, progressive shortness of breath and painful swelling of throat for seven days. Chest radiograph showed left hemithorax homogenous opacity with contralateral mediastinal shift. Complete haemogram and other blood investigations revealed neutrophilic leucocytosis and raised C-reactive protein. Gram stain and aerobic culture of sputum, pleural fluid and blood were inconclusive. As there was no relief of symptoms even after empirical treatment with antibiotics, Contrast Enhanced Computed Tomography (CECT) scan of neck and thorax was done, and it showed bilateral ectatic internal jugular veins with intravascular thrombus and consolidation of left lung with ipsilateral pleural effusion. Ultrasonography of neck confirmed the presence of thrombus in internal jugular vein on both sides. She was started on intravenous clindamycin and subcutaneous anticoagulants. Gradually the symptoms of the patient resolved. To conclude with, despite being called a "forgotten disease", Lemierre's syndrome requires strong clinical suspicion and prompt management to prevent mortality. [ABSTRACT FROM AUTHOR]