Sudden gamer death: non-violent death cases linked to playing video games.

BACKGROUND AND AIMS: Internet gaming disorder (IGD) is an emerging problem. Rarely, media reports about people, who have died during playing video games, but thus far no systematic, scientific study is available about the topic. We investigated such cases, looking for common characteristics, connection between gaming and death, and the possible reasons leading to death. METHODS: Cases were collected through internet search with general keywords, with ones specific to identified cases, and by working along cross references. RESULTS: 24 cases were found: one from 1982, the others between 2002 and 2021. Twenty-three of the victims were male, age ranged from 11 to 40 years. More than half of the cases originated from Southeast Asia, and 12 deaths happened in internet cafes. Gamers played action-rich multiplayer games. In 18 cases the gaming session before death was extremely long (around a day or even several days) with minimal rest. The cause of death was pulmonary embolism in 5 cases, cerebral hemorrhage in 2 cases, most of the rest was presumably due to fatal cardiac arrhythmia. DISCUSSION: Long sedentary position and dehydration may precipitate thromboembolism, acute blood pressure elevation during gaming may promote cerebral hemorrhage, and several factors (including acute and chronic sleep deprivation, exhaustion, stress) can lead to acute autonomic dysfunction and fatal arrhythmia. CONCLUSION: Incidence of non-violent death cases linked to playing video games is presumably very low. It mostly occurs in young males and it is often characterized by extremely long gaming time.

[Transient elastography as a predictor of oesophageal varices in patients with liver cirrhosis]. / Tranziens elasztográfia mint a nyelocso-varicositas prediktora májcirrhosisban szenvedo betegekben.

INTRODUCTION: One of the most serious complications of liver cirrhosis is variceal bleeding. Early recognition of the oesophageal varices is of primary importance in the prevention of variceal bleeding. Endoscopy is the only means to directly visualize varices and measure their size, as one of the most important predictor of the risk of bleeding. During the course of cirrhosis repeated oesophago-gastro-bulboscopic examinations are recommended. As these interventions are expensive and often poorly accepted by patients who may refuse further follow-up, there is a need for non-invasive methods to predict the progression of portal hypertension as well as the presence and the size of oesophageal varices. After several combinations of biological and ultrasonographical parameters proposed for the detection of advanced fibrosis, it was suggested that liver stiffness measured by transient elastography, a novel non-invasive technology may reflect not only fibrosis and portal pressure but it may even predict the presence or absence of large oesophageal varices in patients with cirrhosis. AIM: The aim of the authors was to study the diagnostic accuracy of transient elastography using FibroScan for selecting patients who are at risk of bearing large (Paquet-grade ≥ II) oesophageal varices and high risk of bleeding. METHOD: The authors performed upper tract endoscopy and transient elastography in 74 patients with chronic liver disease (27 patients with chronic hepatitis and 47 patients with liver cirrhosis). The relationships between the presence of oesophageal varices (Paquet-grade 0-IV) and liver stiffness (kPa), as well as the hematological and biochemical laboratory parameters (prothrombine international normalized ratio, platelet count, aspartate aminotransferase, alanine aminotransferase, albumin, and aspartate aminotransferase/platelet ratio index) were investigated. The predictive role of liver stiffness for screening patients with varices and those who are at high risk of variceal bleeding was also analysed. RESULTS: Liver stiffness values significantly correlated with the grade of oesophageal varices (Paquet-grade) (r = 0.67, p<0.0001). The liver stiffness value of 19.2 kPa was highly predictive for the presence of oesophageal varices (AUROC: 0.885, 95% CI: 0.81-0.96) and for the presence of high grade varices (P≥II) (AUROC: 0.850, 95% CI: 0.754-0.94). Using the cut-off value of 19.2 kPa, the sensitivity of transient elastography was 85%, specificity was 87%, positive predictive value was 85%, negative predictive value was 87% and validity was 86% for the detection of varices. Liver stiffness values less than 19.2 kPa were highly predicitive for the absence of large (P≥II) varices (sensitivity, 95%; specificity, 70%; positive predictive value, 54%; negative predictive value, 97%). CONCLUSIONS: Transient elastography may help to screen patients who are at high risk of bearing large (P≥II) oesophageal varices which predict variceal bleeding and, therefore, need endoscopic screening. Lives stiffness values higher than 19.2 kPa indicate the need for oesophageal-gastro-bulboscopy, while liver stiffness values lower than 19.2 kPa make the presence of large oesophageal varices unlikely.

Physical Properties of Blood and their Relationship to Clinical Conditions.

It has been long known that blood health heavily influences optimal physiological function. Abnormalities affecting the physical properties of blood have been implicated in the pathogenesis of various disorders, although the exact mechanistic links between hemorheology and clinical disease manifestations remain poorly understood. Often overlooked in current medical practice, perhaps due to the promises offered in the molecular and genetic era, the physical properties of blood which remain a valuable and definitive indicator of circulatory health and disease. Bridging this gap, the current manuscript provides an introduction to hemorheology. It reviews the properties that dictate bulk and microcirculatory flow by systematically dissecting the biomechanics that determine the non-Newtonian behavior of blood. Specifically, the impact of hematocrit, the mechanical properties and tendency of red blood cells to aggregate, and various plasma factors on blood viscosity will be examined. Subsequently, the manner in which the physical properties of blood influence hemodynamics in health and disease is discussed. Special attention is given to disorders such as sickle cell disease, emphasizing the clinical impact of severely abnormal blood rheology. This review expands into concepts that are highly topical; the relation between mechanical stress and intracellular homeostasis is examined through a contemporary cell-signaling lens. Indeed, accumulating evidence demonstrates that nitric oxide is not only transported by erythrocytes, but is locally produced by mechanically-sensitive enzymes, which appears to have intracellular and potentially extracellular effects. Finally, given the importance of shear forces in the developing field of mechanical circulatory support, we review the role of blood rheology in temporary and durable mechanical circulatory support devices, an increasingly utilized method of life support. This review thus provides a comprehensive overview for interested trainees, scientists, and clinicians.

L-arginine, asymmetric and symmetric dimethylarginine for early outcome prediction in unselected cardiac arrest victims: a prospective cohort study.

Early prediction of the mortality, neurological outcome is clinically essential after successful cardiopulmonary resuscitation. To find a prognostic marker among unselected cardiac arrest survivors, we aimed to evaluate the alterations of the L-arginine pathway molecules in the early post-resuscitation care. We prospectively enrolled adult patients after successfully resuscitated in- or out-of-hospital cardiac arrest. Blood samples were drawn within 6, 24, and 72 post-cardiac arrest hours to measure asymmetric and symmetric dimethylarginine (ADMA and SDMA) and L-arginine plasma concentrations. We recorded Sequential Organ Failure Assessment, Simplified Acute Physiology Score, and Cerebral Performance Category scores. Endpoints were 72 h, intensive care unit, and 30-day mortality. Among 54 enrolled patients [median age: 67 (61-78) years, 48% male], the initial ADMA levels were significantly elevated in those who died within 72 h [0.88 (0.64-0.97) µmol/L vs. 0.55 (0.45-0.69) µmol/L, p = 0.001]. Based on receiver operator characteristic analysis (AUC = 0.723; p = 0.005) of initial ADMA for poor neurological outcome, the best cutoff was determined as > 0.65 µmol/L (sensitivity = 66.7%; specificity = 81.5%), while for 72 h mortality (AUC = 0.789; p = 0.001) as > 0.81 µmol/L (sensitivity = 71.0%; specificity = 87.5%). Based on multivariate analysis, initial ADMA (OR = 1.8 per 0.1 µmol/L increment; p = 0.002) was an independent predictor for 72 h mortality. Increased initial ADMA predicts 72 h mortality and poor neurological outcome among unselected cardiac arrest victims.

Thrombosis preventive potential of chicory coffee consumption: a clinical study.

The protective effects of plant polyphenol intake on cardiovascular morbidity and mortality are widely acknowledged. Caffeine-free chicory coffee is a rich source of plant phenolics, including caffeic acid, which inhibits in vitro platelet aggregation, and also phenylpyruvate tautomerase enzymatic activity of the proinflammatory cytokine, macrophage migration inhibitory factor (MIF). To assess whether chicory coffee consumption might confer cardiovascular benefits a clinical intervention study was performed with 27 healthy volunteers, who consumed 300 mL chicory coffee every day for 1 week. The dietary intervention produced variable effects on platelet aggregation, depending on the inducer used for the aggregation test. Whole blood and plasma viscosity were both significantly decreased, along with serum MIF levels, after 1 week of chicory coffee consumption. Moreover, significant improvements were seen in red blood cell deformability. No changes in hematocrit, fibrinogen level or red blood cell counts were detected. The full spectrum of these effects is unlikely to be attributable to a single compound present in chicory coffee, nevertheless, the phenolics, including caffeic acid, are expected to play a substantial role. In conclusion, our study offers an encouraging starting-point to delineate the antithrombotic and antiinflammatory effects of phenolic compounds found in chicory coffee.

Hemorheological Parameters in Diabetic Patients: Role of Glucose Lowering Therapies.

Diabetes mellitus influences several important hemorheological parameters including blood viscosity, erythrocyte aggregation and deformability. In the present study, 159 type-2 diabetic patients and 25 healthy controls were involved. Patient's age, body weight, body mass index (BMI), smoking habits, physical activity, history of cardiovascular diseases, current antidiabetic therapy and concomitant medication were recorded. Patients were grouped according to their antidiabetic treatment with insulin, or with one or more of the following antidiabetic drugs: metformin, sulfonylureas, acarbose, or no antidiabetic therapy. Hemorheological measurements (hematocrit, erythrocyte aggregation, plasma fibrinogen, whole blood and plasma viscosity), von Willebrand factor activity, and platelet aggregation measurements were performed. Platelet aggregation was investigated with the method of Born. Plasma viscosity and red blood cell aggregation were significatly higher in diabetes. No significant difference was found in hemorheological parameters between different antidiabetic regimens. Whole blood and plasma viscosity and red blood cell aggregation correlated with glucose levels but not with HbA1C levels. In conclusion, plasma and whole blood viscosity, as well as red blood cell aggregation appear to be associated with concurrent hyperglycemia, but not with the quality of glycemic control or the applied antidiabetic treatment. Platelet aggregation induced by ADP or epinephrine does not seem to be associated with diabetes even at subthreshold doses.

Peripartum Investigation of Red Blood Cell Properties in Women Diagnosed with Early-Onset Preeclampsia.

We investigated peripartum maternal red blood cell (RBC) properties in early-onset preeclampsia (PE). Repeated blood samples were taken prospectively for hemorheological measurements at PE diagnosis (n = 13) or during 26-34 weeks of gestation in healthy pregnancies (n = 24), then at delivery, and 72 h postpartum. RBC aggregation was characterized by M index (infrared light transmission between the aggregated RBCs in stasis) and aggregation index (AI-laser backscattering from the RBC aggregates). We observed significantly elevated RBC aggregation (M index = 9.8 vs. 8.5; AI = 72.9% vs. 67.5%; p < 0.001) and reduced RBC deformability in PE (p < 0.05). A positive linear relationship was observed between AI and gestational age at birth in PE by regression analysis (R2 = 0.554; p = 0.006). ROC analysis of AI showed an AUC of 0.84 (0.68-0.99) (p = 0.001) for PE and indicated a cutoff of 69.4% (sensitivity = 83.3%; specificity = 62.5%), while M values showed an AUC of 0.75 (0.58-0.92) (p = 0.019) and indicated a cutoff of 8.39 (sensitivity = 90.9% and specificity = 50%). The predicted probabilities from the combination of AI and M variables showed increased AUC = 0.90 (0.79-1.00) (p < 0.001). Our results established impaired microcirculation in early-onset PE manifesting as deteriorated maternal RBC properties. The longer the pathologic pregnancy persists, the more pronounced the maternal erythrocyte aggregation. AI and M index could help in the prognostication of early-onset PE, but further investigations are warranted to confirm the prognostic role before the onset of symptoms.

Hemorheological Alterations in Patients with Heart Failure with Reduced Ejection Fraction Treated by Resveratrol.

OBJECTIVES: Several beneficial effects of resveratrol have already been published. This study evaluated the effect of resveratrol on the hemorheological parameters in patients with heart failure with reduced ejection fraction. METHODS: In our double-blind, placebo-controlled human clinical trial, we enrolled 60 outpatients with heart failure. Patients were randomized into two groups: receiving either 100 mg resveratrol capsule daily or placebo for 3 months. Hematocrit was determined by microhematocrit centrifuge. Plasma and whole blood viscosity was evaluated by capillary viscometer. Erythrocyte aggregation was measured by both LORCA and Myrenne aggregometers. LORCA ektacytometer was used for measuring erythrocyte deformability. Exercise capacity was assessed by a 6-minute walk test. RESULTS: Resveratrol treatment did not have any significant effect on hematocrit and viscosity. The erythrocyte deformability also remained unchanged. However, significant improvement of red blood cell aggregation was observed in the resveratrol group compared to baseline after 3 months. Furthermore, positive correlation was found between the exercise capacity and the hemorheological properties (Hct, WBV, and RBC aggregation and deformability) as well. CONCLUSION: These findings indicate that resveratrol can significantly reduce red blood cell aggregation, which may positively influence microcirculation, which may contribute to the improvement of tissue perfusion and oxygen supply in heart failure.

[The prognostic value of cytokeratin-18 cell death marker in cardiac arrest survivors]. / A citokeratin-18 sejthalálmarker vizsgálata sikeres cardiopulmonalis resuscitatión átesett betegpopulációban.

Introduction: Cytokeratin-18 (CK-18) is releasing into the blood during systemic cell death due to ischemia-reperfusion injury after cardiac arrest. Its caspase-cleaved form is specific to apoptosis. Previous investigations proved their prognostic value in different conditions. We firstly investigated the prognostic value of these markers after cardiac arrest. Method: Plasma samples of 40 resuscitated patients were collected 6, 24, and 72 hours after successful resuscitation to determine the marker concentrations. We investigated the association of the markers with the 30-day mortality, neurological outcome, circumstances of the cardiac arrest, laboratory and physical parameters. Results: Resuscitated patients had highly elevated CK-18 levels (3842 vs. 242; 559; 1644 ng/L) and decreased caspase-cleaved CK-18/CK-18 ratio (0.14 vs. 0.58; 0.22; 0.24) compared to healthy subjects, septic and postoperative patients suggesting severe grade of cell death, mainly necrosis. Neither the marker concentrations nor their kinetics showed difference between survivors and non-survivors. They did not show association with the length of the resuscitation, the initial rhythm or the neurological outcome either. CK-18 decreased in patients with good renal function in contrast to patients with renal failure. Significant negative correlation was observed between the 6-hour cytokeratin-18 and hemoglobin concentrations (r = -0.400, p<0.01), while the 30-day survival was associated with lower hemoglobin levels. Conclusion: Surprisingly the biomarkers did not show prognostic value among resuscitated population. The outcome is probably not determined by the complete cell damage, but the loss of a small group of cells with critical role and the reserve capacity of the patient. Orv Hetil. 2020; 161(1): 26-32.

Diet-Dependent and Diet-Independent Hemorheological Alterations in Celiac Disease: A Case-Control Study.

INTRODUCTION: Hemorheology is the study of the flow properties of the blood and its elements, which, together with natural anticoagulants, are important determinants of cardiovascular events. This study aimed to assess hemorheological and natural anticoagulant profiles of patients with celiac disease (CeD) comprehensively. METHODS: Our study is a case-control study (registered under ISRCTN49677481) comparing patients with CeD with age- and sex-matched control subjects (1:1). We measured erythrocyte deformability (ED) at high (3-30 Pa) and low shears (0.3-3 Pa), erythrocyte aggregation, whole blood viscosity, plasma viscosity, and natural anticoagulants (protein C, protein S, and antithrombin activity). Adherence to gluten-free diet was estimated through dietary interview and urine gluten immunogenic peptide (urine GIP) detection. RESULTS: After matching, we analyzed the data of 100 study participants. ED at high shears was impaired in CeD (P < 0.05 for all shears, confirmed by random forest analysis) independently of findings on CeD-specific serological assessment and urine GIP detection but slightly dependently on dietary adherence (P = 0.025 for 30 Pa shear). ED at low shears seemed to be impaired only in urine GIP+ CeD patients (P < 0.05 for all comparisons with urine GIP- CeD patients and control subjects). All parameters describing erythrocyte aggregation and whole blood viscosity were shifted toward a prothrombotic direction in patients with CeD with poor dietary adherence compared with those with good dietary adherence. Plasma viscosity and activity of natural anticoagulants did not differ across groups. DISCUSSION: We observed diet-dependent and diet-independent prothrombotic hemorheological alterations in CeD, which can contribute to the elevated cardiovascular risk. The untoward metabolic changes during gluten-free diet, which can further aggravate hemorheological status, may indicate the implementation of prevention strategies.(Equation is included in full-text article.).

Associations of adiponectin with paraoxonase 1 and sE-selectin in hemodialyzed patients.

BACKGROUND/AIMS: In hemodialyzed (HD) patients, adiponectin and sE-selectin levels are elevated, while antioxidant paraoxonase 1 activity (PON1) is decreased. We determined if the hyperadiponectinemia in HD patients has a protective effect on the decrease in PON1 and elevation in sE-selectin in kidney failure. METHODS AND DESIGN: Predialysis serum adiponectin, PON1 and sE-selectin as well as other metabolic variables were measured in 70 HD patients. RESULTS: Adiponectin had (1) no association with PON1 or sE-selectin, (2) a positive association with dialysis efficiency and HDL-C, and (3) an inverse association with BMI, waist circumference, HOMA IR, triglyceride, hsCRP, fibrinogen, and albumin. Moreover, albumin, BMI, and HOMA-IR were independent negative predictors of adiponectin. CONCLUSIONS: In kidney failure, in contrast to normal renal function, higher adiponectin levels had no correlation with PON1 activity or the sE-selectin level. However, adiponectin has an association with dialysis efficiency and, similar to individuals with preserved kidney function, traits of metabolic syndrome. In addition to BMI and HOMA-IR, the serum albumin concentration is also one of the independent negative predictors of the serum adiponectin level. Collectively, these findings may add details to the understanding of the role that adiponectin plays in chronic renal disease related to 'reverse epidemiology'.

Effect of Sclerovit on endothelial dysfunction, hemorheological parameters, platelet aggregation, plasma concentration of homocysteine and progression of atherosclerosis in patients with vascular diseases.

In our prospective study the effect of Sclerovit (0.8 mg folic acid, 20 mug vitamin B12,5 mg vitamin B6,100 mg vitamin E) on inflammatory markers, hemorheological parameters, platelet aggregation, von Willebrand factor activity as a marker of endothelium dysfunction, plasma lipids, plasma levels of folic acid, vitamin B12 and homocysteine (hcy), flow mediated vasodilatation (FMD) and thickness of carotis intima-media after 1 and 6 months of treatment in patients with vascular diseases (10 patients took 1 capsule, 10 patients 2 capsules of Sclerovit and 10 patients placebo) was determined.Plasma level of vitamin B12, folic acid and elongation index of red blood cells (RBC) increased significantly (p<0.05-0.001), hcy and triglyceride concentrations decreased significantly (p<0.05-0.001) in patients taking Sclerovit. HDL-cholesterol, RBC count, hematocrit, plasma and whole blood viscosity increased significantly (p<0.05-0.001) both in patients taking placebo or vitamins. Fibrinogen and CRP showed a significant (p<0.05-0.01) increase in patients on placebo, but did not change in patients on Sclerovit therapy. FMD showed a significant (p<0.05) amelioration in patients on 1 capsule of Sclerovit.Beside the favorable effects of Sclerovit on some of the measured parameters, the observed deterioration in hemorheological parameters can correlate with the contradictory results of large prospective studies with vitamins.

Haemorheological and haemostatic alterations in coeliac disease and inflammatory bowel disease in comparison with non-coeliac, non-IBD subjects (HERMES): a case-control study protocol.

INTRODUCTION: Haemorheological and haemostatic changes predispose to the development of arterial and venous thrombotic events; however, limited information is available on the status of these changes in coeliac disease (CeD) and inflammatory bowel disease (IBD). In this study, we aim to describe the haemorheological and haemostatic profiles of CeD and IBD patients in a Hungarian cohort of patients to investigate whether any alterations contribute to elevated thrombotic risk. METHODS AND ANALYSIS: This is a case-control study involving newly diagnosed and followed CeD and IBD patients with age-matched and sex-matched non-CeD, non-IBD subjects with an allocation ratio of 1:1:1.After informed consent is obtained, a detailed medical history will be collected, including venous and arterial thrombotic risk factors and medications. Symptoms in CeD patients will be assessed with the Gastrointestinal Symptoms Rating Scale, and disease activity in IBD patients will be determined by disease-specific scores. Dietary adherence will be assessed among CeD patients with a thorough interview together with a measurement of self-reported adherence, dietary knowledge and urine analysis (detection of gluten immunogenic peptides). In addition to routine laboratory parameters, haemorheological (ie, erythrocyte deformability and aggregation, viscosity of whole blood and plasma) and haemostatic parameters (eg, protein C, protein S and antithrombin) with immunological indicators (ie, coeliac-specific serology and antiphospholipid antibodies) will be measured from venous blood for every participant.Primary and secondary outcomes will be haemorheological and haemostatic parameters, respectively. Univariate and multivariate statistics will be used to compare CeD and IBD patients to control subjects. Subgroup analysis will be performed by disease type in IBD, (Crohn's disease and ulcerose colitis), dietary adherence in CeD, and disease activity in IBD and CeD. ETHICS AND DISSEMINATION: The study was approved by the Regional and Local Research Ethics Committee, University of Pécs (Ref. No. 6917). Findings will be disseminated at research conferences and in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ISRCTN49677481.

Plasma viscosity: a forgotten variable.

Evaluation of plasma viscosity has been underutilized in the clinical practice. Plasma viscosity is determined by water-content and macromolecular components. Plasma is a highly concentrated protein solution, therefore weak protein-protein interactions can play a role that is not characterized by electrophoresis. The effect of a protein on plasma viscosity depends on its molecular weight and structure. The less spheroid shape, the higher molecular weight, the higher aggregating capacity, and the higher temperature or pH sensitivity a protein has, the higher plasma viscosity results. Plasma is a Newtonian fluid, its viscosity does not depend on flow characteristics, therefore it is simple to measure, especially in capillary viscosimeters. Its normal value is 1.10-1.30 mPa s at 37 degrees C and independent of age and gender. The measurement has high stability and accuracy, thus little alterations may be pathologically important. Inflammations, tissue injuries resulting in plasma protein changes can increase its value with high sensitivity, though low specificity. It can increase in parallel with erythrocyte sedimentation rate (ESR), but it is not influenced by hematocrit (anemia, polycytemia), or time to analysis. Based on these favorable features, in 1942 plasma viscosity was recommended to substitute ESR. In hyperviscosity syndromes plasma viscosity is better in follow-up than ESR. In rheumatoid arthritis, its sensitivity and specificity are better than that of ESR or C-reactive protein. Plasma fibrinogen concentration and plasma viscosity are elevated in unstable angina pectoris and stroke and their higher values are associated with higher rate of major adverse clinical events. Elevation of plasma viscosity correlates to the progression of coronary and peripheral artery diseases. In conclusion, plasma viscosity should be measured routinely in medical practice.

Relation of platelet aggregation and fibrinogen levels to advancing age in aspirin- and thienopyridine-treated patients.

In our present study we investigated the association between platelet aggregation in patients treated with the most widely used antiplatelet agents (100 and 300-325 mg acetylsalicylic acid (ASA), 75 mg clopidogrel, 500 mg ticlopidine and the combination of 100 mg aspirin and 75 mg clopidogrel), fibrinogen levels and aging. Between 2001 and 2005 we measured in vitro platelet aggregation in 5026 vascular patients according to the method of Born. Platelet aggregation was tested with 5 and 10 microM adenosine-diphosphate, 2 microg/ml collagen and 10 microM epinephrine stimulants. Fibrinogen level was simultaneously measured in a subgroup of 3243 patients. The subjects were divided by age into decades. Platelet aggregation increased significantly with advancing age in the case of 100 and 300-325 mg ASA-treated patients (p<0.001). In aspirin-treated patients also fibrinogen levels increased with aging (p<0.001). There was no association between platelet aggregation or fibrinogen levels and aging either in patients treated with 75 mg clopidogrel or with 500 mg ticlopidine. Thienopyridine-treated patients exhibited significantly lower fibrinogen levels than ASA-treated individuals (p<0.001). Our results suggest that advancing age is associated with elevated platelet aggregability in widely used antiplatelet regimens that might contribute to higher risk of cardiovascular events in the elderly.

Viscometer validation studies for routine and experimental hemorheological measurements.

BACKGROUND: Viscosity measurement is challenging due to the internal properties of blood and the artifacts deriving from the various viscometer systems. OBJECTIVE: We aimed to determine the pitfalls of a cone-plate viscometer (Brookfield DV-III Ultra LV) before starting measurements and compare it to our capillary type model (Hemorex Hevimet 40). Effects of sample storage and thermal calibration were assessed as well. METHODS AND RESULTS: Intra-observer variability was studied by 10 replicate measurements of 7 blood samples, mean coefficients of variation were less than 5%. Instruments were compared by measuring 26 blood samples, an average difference of 7% in WBV and 10% in PV was observed. 9 blood samples were stored at 4°C, 22°C and 37°C up to 48 hours to study the effect of storage on viscosity values. WBV at 50 and 100 s-1 became significantly lower after 3 hours at 37°C (p < 0.05). WBV at higher shear rates and PV remained constant at all temperatures. To evaluate the possibility of measuring one sample at different temperatures, 8 blood samples were measured at 40°C with the device calibrated both at 20°C and 40°C; no significant difference was observed. CONCLUSIONS: Thorough validation studies are required before starting experimental and routine viscosity measurements.

The relationship between hemorheological parameters and mortality in critically ill patients with and without sepsis.

PURPOSE: The prognostic scoring systems for mortality of intensive care patients estimate clinical outcome using several physiological and biochemical parameters. In altered hemodynamic conditions of critically ill patients, hemorheological variables may play a significant role in appropriate tissue perfusion. We investigated if hemorheological parameters are altered in critical status and if they could be markers of mortality. METHODS: 112 patients (67.8 ± 12 years, 58 males, 54 females) treated in intensive care unit with different non-surgical diseases were investigated. Routine laboratory parameters and prognostic scores were determined and hemorheological variables (hematocrit, plasma and whole blood viscosity, red blood cell aggregation and deformability) were measured on the 1st and the 2nd day after admission. RESULTS: ICU scores predicted 35.2-41.3% mortality rate, real mortality in intensive care unit was 37.5%, while 30-day mortality was 46.6%. Whole blood viscosity (WBV) and red blood cell (RBC) deformability were lower, red blood cell aggregation was higher in septic than in nonseptic patients (p < 0.05). In septic patients calcium was increased, osmolality was decreased, while in nonseptic patients WBV and RBC aggregation were higher in nonsurvivors compared to survivors (p < 0.05). Worsening of RBC deformability from day 1 to day 2 predicted higher mortality (p < 0.05). CONCLUSION: Calcium and osmolality level were associated with outcome in sepsis. Whole blood viscosity, red blood cell aggregation and change in red blood cell deformability could predict mortality in nonseptic patients and they may add prognostic information over the ICU scores. Further investigations are needed to evaluate the benefit of our findings in clinical practice.

The impact of post-radioiodine therapy SPECT/CT on early risk stratification in differentiated thyroid cancer; a bi-institutional study.

OBJECTIVE: SPECT/CT has numerous advantages over planar and traditional SPECT images. The aim of this study was to evaluate the role of post-radioiodine therapy SPECT/CT of patients with differentiated thyroid cancer (DTC) in early risk classification and in prediction of late prognosis. PATIENTS AND METHODS: 323 consecutive patients were investigated after their first radioiodine treatment (1100-3700 MBq). Both whole body scan and SPECT/CT images of the head, neck, chest and abdomen regions were taken 4-6 days after radioiodine therapy. Patients were re-evaluated 9-12 months later as well as at the end of follow up (median 37 months). RESULTS: Post-radioiodine therapy SPECT/CT showed metastases in 22% of patients. Lymph node, lung and bone metastases were detected in 61, 13 and 5 patients, respectively, resulting in early reclassification of 115 cases (36%). No evidence of disease was found in 251 cases at 9-12 months after radioiodine treatment and 269 patients at the end of follow-up. To predict residual disease at the end of follow-up, the sensitivities, specificities and diagnostic accuracies of the current risk classification systems and SPECT/CT were: ATA: 77%, 47% and 53%; ETA: 70%, 62% and 64%; SPECT/CT: 61%, 88% and 83%, respectively. There was no difference between cohorts of the two institutions when data were analyzed separately. CONCLUSIONS: Based on our bi-institutional experience, the accuracy of post-radioiodine SPECT/CT outweighs that of the currently used ATA and ETA risk classification systems in the prediction of long-term outcome of DTC.

Aspirin resistance: possible roles of cardiovascular risk factors, previous disease history, concomitant medications and haemorrheological variables.

BACKGROUND AND OBJECTIVE: Recent studies have described the incidence (approximately one in eight high-risk patients will experience a further atherothrombotic event over a 2-year period) of aspirin (acetylsalicylic acid) resistance and its possible background. The aim of this study was to compare the characteristics (risk profile, previous diseases, medications and haemorrheological variables) of patients in whom aspirin provided effective platelet inhibition with those in whom aspirin was not effective in providing platelet inhibition. METHODS: 599 patients with chronic cardio- and cerebrovascular diseases (355 men, mean age 64 +/- 11 years; 244 women, mean age 63 +/- 10 years) taking aspirin 100-325 mg/day were included in the study. Blood was collected between 8:00am and 9:00am from these patients after an overnight fast. The cardiovascular risk profiles, history of previous diseases, medication history and haemorrheological parameters of patients who responded to aspirin and those who did not were compared. Platelet and red blood cell (RBC) aggregation were measured by aggregometry, haematocrit by a microhaematocrit centrifuge, and plasma fibrinogen by Clauss' method. Plasma and whole blood viscosities were measured using a capillary viscosimeter. RESULTS: Compared with aspirin-resistant patients, patients who demonstrated effective aspirin inhibition had a significantly lower plasma fibrinogen level (3.3 g/L vs 3.8 g/L; p < 0.05) and significantly lower RBC aggregation values (24.3 vs 28.2; p < 0.01). In addition, significantly more patients with effective aspirin inhibition were hypertensive (80% vs 62%; p < 0.05). Patients who had effective platelet aggregation were significantly more likely to be taking beta-adrenoceptor antagonists (75% vs 55%; p < 0.05) and ACE inhibitors (70% vs 50%; p < 0.05), whereas patients with ineffective platelet aggregation were significantly more likely to be taking HMG-CoA reductase inhibitors (statins) [52% vs 38%; p < 0.05]. Use of statins remained an independent predictor of aspirin resistance even after adjustment for risk factors and medication use (odds ratio 5.92; 95% CI 1.83, 16.9; p < 0.001). CONCLUSIONS: The mechanisms underlying aspirin resistance are multifactorial. Higher fibrinogen concentrations increase RBC aggregation and can also result in increased platelet aggregation. The higher rate of hypertension in patients with effective platelet aggregation on aspirin could explain the differences in beta-adrenoceptor antagonist and ACE inhibitor use between these patients and aspirin-resistant patients. Furthermore, an additive effect of these drugs may contribute to effective antiplatelet therapy. It is also possible that drug interactions with statins might reduce aspirin bioavailability and/or activity, thereby reducing platelet inhibition in aspirin-resistant patients.

Serum procalcitonin level and leukocyte antisedimentation rate as early predictors of respiratory dysfunction after oesophageal tumour resection.

INTRODUCTION: Postoperative care after oesophageal tumour resection holds a high risk of respiratory complications. We therefore aimed to determine the value of systemic inflammatory markers in predicting arterial hypoxaemia as the earliest sign of developing lung injury after oesophageal tumour resection. METHODS: In a prospective observational study, 33 consecutive patients were observed for three days (T1-T3) after admission (T0) to an intensive care unit following oesophageal tumour resection. The daily highest values of the heart rate, axillary temperature, leukocyte count and PaCO2 were recorded. Serum C-reactive protein and procalcitonin concentrations and the leukocyte antisedimentation rate (LAR) were determined at T1 and T2. Respiratory function was monitored 6-hourly measurement of the PaO2/FIO2 ratio, and the lowest value was recorded at T3. Patients were categorised as normoxaemic or hypoxaemic using the cutoff value of 300 mmHg for PaO2/FIO2. RESULTS: Seventeen out of 33 patients were classified as hypoxaemic and 16 patients as normoxaemic at T3. Increases of temperature at T0 and of the procalcitonin and LAR values at T2 were predictive of hypoxaemia at T3 (P < 0.05, P < 0.01 and P < 0.001, respectively). The area under the receiver-operating characteristic curve was 0.65 for the temperature at T0, which was significantly lower than that for the procalcitonin level at T2 (0.83; 95% confidence interval, 0.69-0.97; P < 0.01) and that for LAR at T2 (0.89; 95% confidence interval, 0.77-1.00; P < 0.001). CONCLUSION: These results suggest that an elevated LAR (>15%) and an elevated procalcitonin concentration (>2.5 ng/ml) measured on the second postoperative day can predict next-day arterial hypoxaemia (PaO2/FIO2 < 300 mmHg) after oesophageal tumour resection.