Optical coherence tomography angiography features in Waldenström macroglobulinemia patients without Hyperviscosity syndrome: A pilot prospective study.

PURPOSE: To evaluate the retinal vessel density (VD) with optical coherence tomography angiography (OCTA) in asymptomatic patients affected by Waldenström macroglobulinemia (WM) without hyperviscosity syndrome (HVS) and to highlight the presence of microvascular damage in theese clinically asymptomatic WD patients. DESIGN: Prospective study. METHODS: A total of 43 eyes from 43 WM patients (24 females, 19 males, mean age 55.1 ± 13.6 years) were enrolled from January 2023 to December 2023 in the Eye Clinic of the University of Naples Federico II. Along with WM patients, 40 healthy subjects (HS) (20 females, 20 males, mean age 52.3 ± 15.6 years) with a normal ophthalmic examination and no history of intraocular surgery or retinal pathologic features were included as control group All patients and controls underwent OCTA RESULTS: The two groups were not significantly different for age and sex Visual acuity examination showed no statistically significant difference in BCVA between controls and patients Compared to HS, WD patients showed lower VD values in the SCP in the whole image (47.95 ± 5.17% vs. 52.99 ± 2.52 %; p < 0.001), as well as in the parafovea (53.01 ± 6.69% vs. 55.30 ± 2.61 %; p = 0.002), and fovea (21.38 ± 9.01% vs. 30.31 ± 5.84 %; p < 0.0001). On the other hand, in the DCP VD values were significantly higher in patients compared to controls in the whole image (55.82 ± 8.07% vs. 50.83 ± 5.46 %; p = 0.005), as well as in the parafovea (56.76 ± 6.26% vs. 52.59 ± 5.46 %; p = 0.0001), and fovea (38.75 ± 8.59% vs. 33.43 ± 8.68 %; p < 0.0001). CONCLUSION: The finding that OCTA confirmed the presence of widespread microvascular damage in WD patients clinically silent. Thus, OCTA is a safe rapid imaging technique that could represent a valid biomarker of systemic vascular dysfunction.

Effect of Acoustic Environment in Wards on Postoperative Rehabilitation in Patients with Oral Cancer: A Retrospective Study.

OBJECTIVE: The increase in patient flow, replacement of medical equipment, and variations in surrounding environments induce increasingly serious acoustic environment problems in hospitals. This study aims to provide additional bases for the formulation of subsequent management plans in clinical practice by analyzing the influence of the acoustic environment in wards and the postoperative rehabilitation effect among patients with oral cancer. METHODS: The medical records of 210 patients with oral cancer undergoing surgical treatment in Jinan Stomatological Hospital from February 2020 to October 2022 were selected for retrospective analysis. Patients with the acoustic environment in wards >55 and ≤55 dB were classified as groups A and B, respectively, according to the acoustic environment in wards. The effects of the acoustic environment in wards on postoperative blood pressure, blood viscosity, and blood glucose fluctuation (BGF) were observed to further analyze their relationship. RESULTS: No significant difference was observed in indices such as preoperative systolic pressure (SP), diastolic pressure (DP), cardiac output (CO), postoperative CO, total cholesterol, and low- and high-density lipoproteins between the two groups (P > 0.05). The SP, DP, whole blood low-shear viscosity (WBLSV), whole blood middle-shear viscosity (WBMSV), whole blood high-shear viscosity (WBHSV), and BGF in group B were significantly lower than group A (P < 0.05). Correlation results showed that the total mean value of the acoustic environment in wards was positively correlated with SP, DP, WBLSV, WBMSV, WBHSV, and BGF (P < 0.05). CONCLUSION: The high acoustic environment in wards is significantly positively correlated with postoperative blood pressure, blood viscosity, and BGF in patients with oral cancer. The hospital should focus on and strengthen the management of the acoustic environment in wards, providing additional schemes to promote the postoperative recovery of patients with oral cancer.

Redefining hyperviscosity in acute leukemia: Potential implications for red cell transfusions in the microvasculature.

Hyperleukocytosis is an emergency of acute leukemia leading to blood hyperviscosity, potentially resulting in life-threatening microvascular obstruction, or leukostasis. Due to the high number of red cells in the circulation, hematocrit/hemoglobin levels (Hct/Hgb) are major drivers of blood viscosity, but how Hct/Hgb mediates hyperviscosity in acute leukemia remains unknown. In vivo hemorheological studies are difficult to conduct and interpret due to issues related to visualizing and manipulating the microvasculature. To that end, a multi-vessel microfluidic device recapitulating the size-scale and geometry of the microvasculature was designed to investigate how Hct/Hgb interacts with acute leukemia to induce "in vitro" leukostasis. Using patient samples and cell lines, the degree of leukostasis was different among leukemia immunophenotypes with respect to white blood cell (WBC) count and Hct/Hgb. Among lymphoid immunophenotypes, severe anemia is protective against in vitro leukostasis and Hct/Hgb thresholds became apparent above which in vitro leukostasis significantly increased, to a greater extent with B-cell acute lymphoblastic leukemia (ALL) versus T-cell ALL. In vitro leukostasis in acute myeloid leukemia was primarily driven by WBC with little interaction with Hct/Hgb. This sets the stage for prospective clinical studies assessing how red cell transfusion may affect leukostasis risk in immunophenotypically different acute leukemia patients.

Rheological properties of blood in multiple myeloma patients.

Multiple myeloma (MM) is considered to be one of the hematological malignancies formed by excessive and abnormal proliferation of plasmocytes. Among other parameters, several blood tests are used to diagnose multiple myeloma. The hemorheological profile in multiple myeloma is not widely studied. Hemorheology includes the study of measuring the deformability and aggregation of erythrocytes, blood viscosity, and sedimentation rate. The degree of deformability of blood cells is necessary to maintain proper vital functions. Proper deformability of red blood cells ensures proper blood circulation, tissue oxidation and carbon dioxide uptake. The aim of the study was to compare morphology and blood rheology parameters in patients with MM and healthy individuals. The study included 33 patients with MM, and 33 healthy subjects of the same age. The hematological blood parameters were evaluated using ABX MICROS 60 hematology analyzer. The LORCA Analyzer to study erythrocyte aggregation and deformability. Patients with MM had lower red blood cells count (RBC) (9.11%) (p < 0.001) and half time of total aggregation (T1/2) (94.29%) (p < 0.001) values and higher mean corpuscular volume (MCV) (5.50%) (p < 0.001), aggregation index (AI) (68.60%) (p < 0.001), total extent of aggregation (AMP) (87.92%) (p < 0.001) values than the healthy control group. Aggregation in patients with MM is different compared to healthy individuals. It was observed that the percentage of cell aggregation is almost 50% higher than in the control group. The study of morphology, aggregation and deformability of erythrocytes in patients with suspected MM may be helpful in making clinical decisions.

Thrombotic Risk and Calculated Whole Blood Viscosity in a Cohort of Patients With New Diagnosis of Multiple Myeloma.

The pathogenesis of venous thromboembolism in multiple myeloma is still poorly understood because multiple factors are involved. In particular, the increase in whole blood viscosity has a key role and, therefore, we performed an evaluation of some hemorheological determinants in multiple myeloma patients, putting them in relation to the thrombotic risk, with the aim to evaluate if an alteration of the hemorheological pattern was associated with a higher thrombotic risk. We performed an observational retrospective cohort study with data collected from January 2017 to September 2022. In a group of 190 patients with newly diagnosed multiple myeloma, we have examined the trend of calculated blood viscosity according to the Merrill formula, and we stratified the patients for the thrombotic risk in accordance with the IMWG/NCCN guidelines and with IMPEDE VTE score. Using the thrombotic risk stratification proposed by IMWG/NCCN any variation in calculated blood viscosity is evident, while, with the IMPEDE VTE score, we observed an increase in calculated blood viscosity in patients with "intermediate + high" risk. The calculated blood viscosity is higher in subjects presenting an "intermediate + high" thrombotic risk according to the IMPEDE VTE score. This association could therefore lay the groundwork for further research with the aim to confirm the role of hemorheological pattern in MM-related thrombotic risk.

Comparative analysis of RADAR vs. conventional techniques for AVF maturation in patients with blood viscosity and vessel elasticity-related diseases through fluid-structure interaction modeling: Anemia, hypertension, and diabetes.

PURPOSE: This study aims to compare two surgical techniques, the standard Vein-to-Artery and the newer Artery-to-Vein (Radial Artery Deviation And Reimplantation; RADAR), for enhancing the success of Arterio-Venous Fistula maturation in end-stage renal disease patients. The impact of diseases like anemia, diabetes, hypertension, and chronic kidney disease were considered. The goals are to advance Arterio-Venous Fistula (AVF) surgery, improve patient outcomes, and contribute to evidence-based surgical guidelines. METHODS: Fluid-structure interaction modeling was employed to investigate how hemodynamic and mechanical stresses impact arteriovenous fistula maturation, with a particular focus on the role of wall shear stress in determining maturation outcomes. The critical threshold for vessel injury was identified as wall shear stress values exceeding 35 N/m2, while stenosis formation was projected to occur at levels below 1 N/m2. This work introduced a novel approach by considering disease-related factors, including blood viscosity (anemia), and vessel elasticity (diabetes, hypertension, and chronic kidney diseases), which directly influence hemodynamics and the generation of wall shear stress. Furthermore, the model was designed to incorporate varying thicknesses and elasticities for both the vein and artery, accurately representing authentic vascular anatomy. RESULTS: The RADAR technique has demonstrated superior performance compared to the standard technique by providing appropriate wall shear stress in critical regions and minimizing the risk of wall damage. Its use of a thicker vessel also reduces the risk of vessel injury, making it particularly effective for patients with Chronic Kidney Disease (CKD), hypertension, anemia, and diabetes, ensuring optimal blood flow and fewer complications. However, there are minor concerns about stenosis formation in hypertension and anemia cases, which could be mitigated by adjusting the anastomosis angle to be lower than 30°. CONCLUSION: Diabetes and hypertension have significant physiological effects that increase the risks associated with arteriovenous fistula maturation. The anemic condition resulting from CKD may help reduce vessel injury but raises concerns about potential stenosis formation. Despite these co-morbidities, the RADAR technique has demonstrated its ability to induce more favorable hemodynamic changes, promoting arteriovenous fistula maturation.

Síndrome de hiperviscosidade em paciente com mieloma múltiplo / Hyperviscosity syndrome in multiple myeloma patients

O mieloma múltiplo é uma neoplasia progressiva e incurável de células B, caracterizado pela proliferação desregulada e clonal de plasmócitos na medula óssea. A síndrome de hiperviscosidade é uma das complicações relacionadas às gamopatias monoclonais, sendo considerada emergência oncológica. O objetivo deste estudo foi descrever o quadro clínico de um paciente diagnosticado com mieloma múltiplo que apresentou síndrome de hiperviscosidade, avaliando a prevalência de sinais e sintomas, bem como características fisiopatológicas dessa entidade clínica. Foi revisado o prontuário de um paciente internado na enfermaria da Clínica Médica do Hospital Regional do Cariri (CE) no período de junho a julho de 2018. Além disso, foi realizada revisão de literatura em base de dados (PubMed®) direcionada ao tema proposto. O diagnóstico de mieloma múltiplo foi comprovado por mielograma, sendo prontamente iniciada a corticoterapia e avaliada a resposta clínica após essa terapêutica. Apesar de incomum e menos frequentemente relacionada ao mieloma múltiplo, a síndrome de hiperviscosidade está relacionada a uma grande taxa de mortalidade quando apresenta diagnóstico tardio. A terapia de primeira linha indicada para a síndrome de hiperviscosidade foi a plasmaferese, no entanto, as condições clínicas (instabilidade hemodinâmica) impossibilitaram sua realização. O desfecho deste caso foi o óbito do paciente. Concluiu-se que o diagnóstico precoce e a intervenção terapêutica estão diretamente relacionados à ocorrência de menor incidência de complicações relacionadas ao mieloma múltiplo e à síndrome de hiperviscosidade.

Multiple myeloma is a progressive and incurable B-cell neoplasm characterized by unregulated and clonal proliferation of plasmocytes in the bone marrow. Hyperviscosity syndrome is one of the complications related to monoclonal gammopathies and is considered an oncological emergency. The aim of this study was to describe the clinical condition of a patient diagnosed with multiple myeloma who presented hyperviscosity syndrome, evaluating the prevalence of symptoms and signs, as well as the pathophysiological characteristics of this clinical entity. The medical records of a patient admitted to the Internal Medicine ward of the Hospital Regional do Cariri (CE) from June to July of 2018 were reviewed. In addition, we conducted a literature review in a database (PubMed®) directed to the theme proposed. The diagnosis of multiple myeloma was confirmed by myelogram, and corticosteroid therapy was promptly initiated and the clinical response was evaluated after this therapy. Although uncommon and less frequently related to multiple myeoloma, hyperviscosity syndrome is related to a high mortality rate when diagnosed late. The first line therapy indicated to hyperviscosity syndrome was plasmapheresis; however, the clinical conditions (hemodynamic instability) precluded its performance. The outcome of this case was the patient's death. Thus, it was concluded that early diagnosis and therapeutic intervention are directly related to the occurrence of lower incidence of complications related to multiple myeloma and hyperviscosity syndrome.

Factores bioquímicos y nutricionales asociados a la viscosidad sanguínea en adultos de la sierra urbana (Imbabura), Ecuador / Biochemical and nutritional factors associated with blood viscosity in adults living in a mountain chain, (Imbabura), Ecuador

La asociación de la viscosidad sanguínea (VS) con la hipertensión y la diabetes mellitus 2, indica que debe ser considerada sobre todo en poblaciones que viven en la sierra donde el hematocrito y la hemoglobina son más elevados. Se evaluó la asociación de la VS con factores de riesgo cardiovascular y de síndrome metabólico (SM) en una población de 237 adultos (20-60 años) de la sierra urbana ecuatoriana. Se calculó el índice de masa corporal (IMC), porcentaje de grasa y agua corporal, se midieron la circunferencia de la cintura (CC) y la presión arterial. Se realizaron determinaciones de parámetros bioquímicos, hematológicos y de VS (mediante fórmula validada). El 14,76% de la población presentó hiperviscosidad (HV). El 42,8% de las personas con HV presentó SM contra 33% en el grupo con normoviscosidad (NV). El ácido úrico (AU) se observó más elevado en los grupos HV y NV con SM. Se encontró una correlación lineal simple de las concentraciones de glucosa (GLU) y de triglicéridos (TRI) con la VS en el grupo HV sin SM. El análisis de regresión lineal múltiple indicó que la GLU, el AU y la presión sistólica son variables que influyen independientemente con el incremento de la VS en el grupo HV sin SM. Las variables GLU y % de agua influyen en el incremento de la VS en el grupo NV sin SM. El incremento de las concentraciones de glucosa y de ácido úrico son los dos factores que mayormente influyen en la VS en esta población.

The association of blood viscosity (BV) with hypertension and diabetes mellitus type 2 indicates that it should be considered, especially in populations living in mountain chains where the hemoglobin and hematocrit values are higher. In fact, this work analyzed the association of BV with nutritional and biochemical risk factors in the development of cardio metabolic diseases in healthy adults (20-60 years old; 46.39% female and 53.61% male) living in the urban Ecuadorian sierra. The body mass index (BMI) was calculated. The body fat percentage, body water percentage, waist circumference (WC) and blood pressure were measured. Determinations of biochemical and hematological parameters were performed using established methodologies and a validated formula was used to determine the BV. Hyperviscosity (HV) was present in 14.76% of the population: 10.46% men, 4.3% women. In this group, 42.8% showed metabolic syndrome (MS) against 33% in the normoviscosity group (NV). Uric acid (UA) was observed statistically higher in HV and NV with MS groups. A simple positive linear correlation was found between glucose (GLU) and triglycerides (TRI) concentrations and BV in HV without MS group. The multiple linear regression analysis indicated that GLU, UA and systolic pressure influence to increase BV in the HV without MS group. Glucose concentration and percentage of water, independently influence the BV in the NV without MS group. The increase in GLU and UA concentrations are the most influencing factors on BV in this population.

Effects of a physical fitness program on memory and blood viscosity in sedentary elderly men

The aim of this study was to investigate the effects of a 6-month exercise program on cognitive function and blood viscosity in sedentary elderly men. Forty-six healthy inactive men, aged 60–75 years were randomly distributed into a control group (n=23) and an experimental group (n=23). Participants underwent blood analysis and physical and memory evaluation, before and after the 6-month program of physical exercise. The control group was instructed not to alter its everyday activities; the experimental group took part in the fitness program. The program was conducted using a cycle ergometer, 3 times per week on alternate days, with intensity and volume individualized at ventilatory threshold 1. Sessions were continuous and maximum duration was 60 min each. There was significant improvement in memory (21%; P<0.05), decreased blood viscosity (−19%; P<0.05), and higher aerobic capacity (48%; P<0.05) among participants in the experimental group compared with the control group. These data suggest that taking part in an aerobic physical fitness program at an intensity corresponding to ventilatory threshold-1 may be considered a nonmedication alternative to improve physical and cognitive function.

Síndrome de hiperviscosidad en pacientes con mieloma múltiple / Hyperviscosity syndrome in patients with multiple myeloma

Objetivos: el mieloma múltiple es una enfermedad de distribución universal. Se determinaron la frecuencia, las características y el tratamiento del síndrome de hiperviscosidad como complicación de esta enfermedad. Método: se realizó un estudio descriptivo retrospectivo que incluyó a 31 pacientes con el diagnóstico de mieloma múltiple atendidos en el servicio de adultos del Instituto de Hematología e Inmunología desde enero del 2007 a junio del 2011. Resultados: la edad media fue de 61 años con un predominio del sexo masculino y el color de la piel blanca. Los pacientes se presentaron con anemia, eritrosedimentación acelerada, hiperproteinemia, hipoalbuminemia, hipergammaglobulinemia, una infiltración media de la médula ósea por células plasmáticas de 63.2 porciento y una viscosidad sérica media de 2.93. El síndrome de hiperviscosidad se observó en 4 (12.9 porciento) pacientes. Las manifestaciones clínicas principales del síndrome de hiperviscosidad fueron los síntomas generales y los síntomas neurológicos y se presentaron con cifras de viscosidad sérica iguales o superiores a 4.5. La proteína monoclonal identificada como responsable del síndrome de hiperviscosidad fue la IgA y la viscosidad sérica fue proporcional a las concentraciones de la paraproteína (p<0.01). Conclusión: el síndrome de hiperviscosidad se presentó en los pacientes estudiados con similares características a lo reportado por otros autores. La plasmaféresis y la quimioterapia fueron los pilares del tratamiento con resultados satisfactorios

Objectives: multiple myeloma is a disease of worldwide distribution. We determined frequency, characteristics and treatment of hyperviscosity syndrome as a complication of this condition. Method: we conducted a retrospective study involving 31 patients with a diagnosis of multiple myeloma treated at the Adult Hematology Service of the Institute of Hematology and Immunology from January 2007 to June 2011. Results: mean age was 61 years with a male predominance and slight predominance in caucasians. The patients presented with anemia, high erythrosedimentation rate, hyperproteinemia, hypoalbuminemia, hypergammaglobulinemia, a median infiltration of bone marrow by plasma cells of 63.2percent and an average serum viscosity of 2.93. Hyperviscosity syndrome was observed in 4 (12.9 percent) patients. The main clinical manifestations of hyperviscosity syndrome were general symptoms and neurological symptoms and presented with serum viscosity at or above 4.5. The monoclonal protein identified as the responsible of the hyperviscosity syndrome was IgA and viscosity was proportional to the concentrations of the paraprotein (p <0.01). Conclusion: the hyperviscosity syndrome is presented in the studied patients with similar characteristics to those reported by other authors. Plasmapheresis and chemotherapy were the mainstays of treatment with satisfactory results

Exogenous normal lymph alleviates microcirculation disturbances and abnormal hemorheological properties in rats with disseminated intravascular coagulation

Disturbances of the microcirculation and abnormal hemorheological properties are important factors that play an important role in disseminated intravascular coagulation (DIC) and result in organ dysfunction or failure. In the present study, we established an animal model of DIC using intravenous Dextran 500 in rats, and used exogenous normal lymph corresponding to 1/15 of whole blood volume for injection through the left jugular vein. We found that normal lymph could improve the blood pressure and survival time of rats with DIC. The results regarding the mesenteric microcirculation showed that the abnormality of the diameter of mesenteric microvessels and micro-blood flow speed in the DIC+lymph group was significantly less than in the DIC+saline group. Whole blood viscosity, relative viscosity, plasma viscosity, hematocrit (Hct), erythrocyte sedimentation rate (ESR), and electrophoresis time of erythrocytes were significantly increased in the DIC+saline group compared to the control group. The electrophoretic length and migration of erythrocytes from the DIC+saline and DIC+lymph groups were significantly slower than the control group. Blood relative viscosity, Hct, ESR, and electrophoretic time of erythrocytes were significantly increased in the DIC+lymph group compared to the control group. Whole blood viscosity, relative viscosity and reduced viscosity were significantly lower in the DIC+lymph group than in the DIC+saline group, and erythrocyte deformability index was also significantly higher than in the DIC+saline and control groups. These results suggest that exogenous normal lymph could markedly improve the acute microcirculation disturbance and the abnormal hemorheological properties in rats with DIC induced by Dextran 500.

Calcium dobesilate may improve hemorheology in patients undergoing coronary artery bypass grafting / Dobesilato de cálcio pode melhorar hemorreologia em pacientes submetidos à cirurgia de revascularização miocárdica

BACKGROUND: Calcium dobesilate is an angioprotective agent that has positive effects on hemorheological parameters. It is an antioxidant that increases endothelial-derived vasodilator substance secretion, there are none that analyze its effects during the postoperative period of patients undergoing myocardial revascularization. OBJECTIVE: We aimed to determine the effects of calcium dobesilate on hemorheological parameters, such as reduced glutathione and malondialdehyde in patients with ischemic heart disease undergoing myocardial revascularization in the postoperative period. METHODS: One hundred and thirty-four patients operated for coronary heart disease were included in this study. Hemorheological, oxidant and antioxidant parameters were measured two days after surgery and after a period of treatment with calcium dobesilate. Then, 500 mg of calcium dobesilate was given twice a day to one group of 68 patients for three months. The control group was composed of 66 patients who did not receive this medication. RESULTS: The increase in the erythrocyte deformability index was found to be significant compared with both the pretreatment values and with the 1st and 2nd values of the control group after calcium dobesilate administration, whereas there were no significant changes in blood viscosity, glutathione (GSH) or malondialdehyde (MDA) values after the calcium dobesilate administration. The same improvement in the CCS class was observed in patients regardless of they received the calcium dobesilate treatment. CONCLUSION: In the present investigation, the same improvement in the CCS class was observed in patients regardless of they received the calcium dobesilate treatment. Improvements with calcium dobesilate were statistically significant only in the increase in erythrocyte flexibility.

ANTECEDENTES: O dobesilato de cálcio é um agente angioprotetor que tem efeitos positivos sobre os parâmetros hemorreológicos. É um antioxidante que aumenta a secreção endotelial derivada da substância vasodilatadora, não há nada que analisar os seus efeitos durante o período pósoperatório de pacientes submetidos a revascularização do miocárdio. OBJETIVO: Nosso objetivo foi determinar os efeitos de dobesilato de cálcio sobre os parâmetros hemorreológicos, tais como glutationa reduzida e malondialdeído em pacientes com doença cardíaca isquêmica submetidos a revascularização do miocárdio no pós-operatório. MÉTODOS: Cento e trinta e quatro pacientes operados por doença cardíaca coronária foram incluídos neste estudo. Parâmetros de oxidante, hemorreológicos e de antioxidantes foram medidos dois dias após a cirurgia e após um período de tratamento com o dobesilato de cálcio. Em seguida, 500 mg de dobesilato de cálcio foi administrado duas vezes por dia para um grupo de 68 pacientes durante três meses. O grupo controle foi composto por 66 pacientes que não receberam essa medicação. RESULTADOS: O aumento do índice de deformabilidade dos eritrócitos foi considerado significativo comparado com ambos os valores pré-tratamento e com os 1º e 2º valores do grupo controle após a administração dobesilato de cálcio, enquanto que não houve alterações significativas na viscosidade do sangue, na glutationa (GSH) ou malondialdeído (MDA) após a administração dobesilato de cálcio. A mesma melhoria na classe CCS foi observada em pacientes independentemente de terem recebido tratamento com dobesilato de cálcio. CONCLUSÃO: Na presente investigação, a mesma melhora na classe CCS foi observada em pacientes independentemente de terem recebido o tratamento com dobesilato de cálcio.

Cerebral hemodynamics: concepts of clinical importance / Hemodinâmica encefálica: conceitos de importância clínica

Cerebral hemodynamics and metabolism are frequently impaired in a wide range of neurological diseases, including traumatic brain injury and stroke, with several pathophysiological mechanisms of injury. The resultant uncoupling of cerebral blood flow and metabolism can trigger secondary brain lesions, particularly in early phases, consequently worsening the patient's outcome. Cerebral blood flow regulation is influenced by blood gas content, blood viscosity, body temperature, cardiac output, altitude, cerebrovascular autoregulation, and neurovascular coupling, mediated by chemical agents such as nitric oxide (NO), carbon monoxide (CO), eicosanoid products, oxygen-derived free radicals, endothelins, K+, H+, and adenosine. A better understanding of these factors is valuable for the management of neurocritical care patients. The assessment of both cerebral hemodynamics and metabolism in the acute phase of neurocritical care conditions may contribute to a more effective planning of therapeutic strategies for reducing secondary brain lesions. In this review, the authors have discussed concepts of cerebral hemodynamics, considering aspects of clinical importance.

Alterações hemodinâmicas e metabólicas do encéfalo ocorrem frequentemente em diversas doenças neurológicas, principalmente em condições de traumatismo cranioencefálico e acidente vascular encefálico, com vários mecanismos patofisiológicos lesionais. O desacoplamento resultante do fluxo sanguíneo e do metabolismo encefálico pode resultar em lesões encefálicas secundárias, principalmente nas primeiras fases, e, consequentemente, no agravamento do desfecho neurológico dos pacientes. Diversos fatores influenciam o fluxo sanguíneo encefálico, entre eles, a concentração sanguínea de gases, viscosidade sanguínea, temperatura corpórea, débito cardíaco, altitude, autorregulação cerebrovascular e acoplamento neurovascular, que é mediado por óxido nítrico (ON), monóxido de carbono (CO), eicosanoides, radicais livres derivados do oxigênio, endotelinas, potássio, íons hidrogênio e adenosinas. Melhor compreensão destes fatores é fundamental para o manejo clínico dos pacientes neurológicos críticos. A avaliação hemodinâmica e metabólica do encéfalo nas lesões encefálicas agudas pode contribuir para o planejamento de estratégias de redução das lesões encefálicas secundárias. Nesta revisão, os autores discutiram princípios da hemodinâmica encefálica, considerando os aspectos de importância clínica.

Efectos proinflamatorios de la contaminación atmosférica / Proinflammatory effects of air pollution in Santiago de Chile

Intermittent exposure of rats to Santiago's traffic pollution is associated to a decrease in growth after more than 100 days (range: 101-111) and to histological lung damage after 90 and particularly after 180 days. Our aim was to assess whether a 90 days exposure of rats to air from a Santiago's heavy traffic avenue, is able to induce a systemic proinflammatory reaction. Thirty-days-old Sprague-Dawley rats (n = 7) were directly exposed to air from a heavy traffic avenue (8 h, 5 days a week, from April 27 to July 29, 2009). Controls (n = 7) breathed animal room air. Rats were weighed twice a week and after completing 90 days of observation, lungs were subjected to histopathology and C reactive protein, viscosity and F2-isoprostane in plasma and microhematocrit were determined in blood samples. Exposure to PM10, PM2.5, ozone, NO2 and CO were estimated from registrations of 4 Santiago's monitoring stations. Plasmatic C reactive protein and viscosity and microhematocrit were significantly increased after 90 days of exposure as compared to controls (p < 0.05). No significant changes were observed in F2-isoprostane, nor in lung histopathology, nor in body weight curve versus time in exposed as compared to control series. Hourly mean value of PM25 in the 8 h of exposure was high: 38.9 ug/m³. It is concluded that 90 days of intermittent exposure of rats to Santiago's air pollution would promote a systemic inflammatory reaction. This response to air pollution might precede the decrease in body growth and the histological lung damage reported previously by our laboratory in the same species after intermittent Santiago's urban air pollution exposure.

La exposición intermitente de ratas centinela a la contaminación del tráfico vehicular de Santiago se ha asociado a disminución del crecimiento corporal después de cien días de exposición (rango: 101-111) y a daño histopatológico del pulmón a los 90 días y más, especialmente a los 180 días de exposición. Nuestro objetivo fue evaluar si la exposición al aire de una avenida con elevado tráfico vehicular durante 90 días era capaz de inducir en la rata una respuesta inflamatoria sistémica. Ratas Sprague-Dawley de 30 días de edad (n = 7) fueron directamente expuestas a respirar el aire de una avenida con elevado flujo vehicular (8 h, 5 días por semana, desde el 27 de abril hasta el 29 de julio de 2009). Las ratas control (n = 7) respiraron aire del bioterio. Las ratas se pesaron dos veces por semana y después de completar 90 días de observación, los pulmones se destinaron a estudio histopatológico. Se realizó microhematocrito y se determinó proteína C reactiva, viscosidad y F2-isoprostano plasmáticos en muestras de sangre. La exposición a PM10, PM2,5, ozono, NO2 y CO se calculó de los registros de cuatro estaciones de monitoreo de Santiago. Después de 90 días de exposición se observó un aumento significativo (p < 0,05) de la proteína C reactiva y de la viscosidad plasmática y también del microhematocrito, en relación a la serie control. No se observaron cambios significativos en F2-isoprostano plasmático, ni en la histopatología pulmonar, ni en la curva de peso corporal versus tiempo al comparar la serie expuesta con la serie control. El promedio horario de PM2,5 en las 8 horas de exposición fue alto: 38,9 ug/m³. Concluimos que 90 días de exposición intermitente a la contaminación aérea de Santiago en el modelo experimental promueve una reacción inflamatoria sistémica. Esta respuesta a la contaminación aérea podría preceder a la disminución del crecimiento corporal y al daño histológico pulmonar encontrado en otro de nuestros estudios en esta misma especie después...

Drag reduction by polyethylene glycol in the tail arterial bed of normotensive and hypertensive rats

This study was designed to evaluate the effect of drag reducer polymers (DRP) on arteries from normotensive (Wistar) and spontaneously hypertensive rats (SHR). Polyethylene glycol (PEG 4000 at 5000 ppm) was perfused in the tail arterial bed with (E+) and without endothelium (E-) from male, adult Wistar (N = 14) and SHR (N = 13) animals under basal conditions (constant flow at 2.5 mL/min). In these preparations, flow-pressure curves (1.5 to 10 mL/min) were constructed before and 1 h after PEG 4000 perfusion. Afterwards, the tail arterial bed was fixed and the internal diameters of the arteries were then measured by microscopy and drag reduction was assessed based on the values of wall shear stress (WSS) by computational simulation. In Wistar and SHR groups, perfusion of PEG 4000 significantly reduced pulsatile pressure (Wistar/E+: 17.5 ± 2.8; SHR/E+: 16.3 ± 2.7 percent), WSS (Wistar/E+: 36; SHR/E+: 40 percent) and the flow-pressure response. The E- reduced the effects of PEG 4000 on arteries from both groups, suggesting that endothelial damage decreased the effect of PEG 4000 as a DRP. Moreover, the effects of PEG 4000 were more pronounced in the tail arterial bed from SHR compared to Wistar rats. In conclusion, these data demonstrated for the first time that PEG 4000 was more effective in reducing the pressure-flow response as well as WSS in the tail arterial bed of hypertensive than of normotensive rats and these effects were amplified by, but not dependent on, endothelial integrity. Thus, these results show an additional mechanism of action of this polymer besides its mechanical effect through the release and/or bioavailability of endothelial factors.

Determinação da viscosidade e composição nutricional de fórmula infantil à base de hidrolisado protéico de frango / Determination of viscosity and nutritional composition of infant formula based on hydrolyzed chicken protein

Objetivo: Desenvolver e caracterizar uma formulação infantil com hidrolisado de carne de frango (FIHF) para crianças de 0 a 12 meses com reações adversas ao leite. Método: Obtenção do hidrolisado a partir da metodologia desenvolvida por Pinto e Silva. A receita da fórmula infantil com carne de frango foi proposta por Carazza e Marcondes e a viscosidade mensurada a partir de reômetro digital.Composição centesimal: umidade, proteínas, cinzas,lipídios, carboidratos e fibras. Todos os testes foram realizados em triplicata. Resultados: Realizaram-se diversos testes com FIHF, resultando na combinaçãode hidrolisado de frango, glicose, sacarose, creme dearroz, óleo de soja, banha de porco e carbonato de cálcio. A viscosidade da FIHF é de 36,9mPas. Os resultados da composição centesimal mostram que em 100g da FIHF há 3,12g de lipídeos totais, 1,32gde proteínas, 0,23g de cinzas, 6,53g de carboidratose 50mg de cálcio, totalizando 63kcal. A composição nutricional em 100g de PLHF é de 3,71g de lipídeostotais, 2,84g de proteínas, 2,17g de cinzas, 7,81gde carboidratos e 76kcal. Conclusões: A preparação desenvolvida constitui boa alternativa alimentar para crianças com reações adversas ao leite em relação às características físico/químicas, ao valor nutricional.

Objective: To develop and characterize a formulation of hydrolyzed infant with chicken meat (FIHF) for children aged 0 to 12 months with adverse reactions to milk. Methods: Obtaining the hydrolyzate from the methodology developed by Pinto and Silva (1999). The recipe of infant formula with chicken meat was proposed by Carazza andMarcondes. Viscosity from digital rheometer. Proximate composition: moisture, protein, ash, lipids, carbohydrates and fiber. All tests were performed in triplicate. Results:There were several tests with FIHF, resulting in a combination of hydrolyzed chicken, glucose, sucrose, cream of rice,soybean oil, lard and calcium carbonate. The viscosity of 36.9mPas FIHF is. The results show that the composition FIHF there in 100g of total lipids 3.12g, 1.32g protein, 0.23g ash,6.53g of carbohydrates and 50mg calcium, totaling 63kcal.The nutritional composition of 100g PLHF is 3.71 g of lipids, proteins 2.84g, 2.17g ash, 7.81g of carbohydrates and 76kcal. Conclusions: The preparation is developed good alternative food for children with adverse reactions to milk in relation to physico/chemical properties, nutritional value.

Leucemia mielóide crônica e síndrome de hiper-viscosidade: relato de caso / Chronicle myeloid leukemia and hiperviscosity syndrome: case report

JUSTIFICATIVA E OBJETIVOS: A hiperleucocitose (> 100 x 10(9)/L) em leucemia mielóide crônica não é uma apresentação comum e pode determinar manifestações clínicas de hiper-viscosidade. As perdas auditiva e visual observadas em pacientes com leucemia são consideradas sintomas incomuns, mas fortemente associados à síndrome da hiper-viscosidade. O objetivo deste estudo foi relatar o caso de um paciente que apresentou perda da audição como manifestação inicial de leucemia mielóide crônica e síndrome de hiper-viscosidade e rever aspectos relacionados a seu tratamento em Medicina Intensiva. RELATO DO CASO: Paciente do sexo masculino, 41 anos, com queixa de tontura havia seis meses sem resposta ao tratamento sintomático, foi admitido no serviço de emergência com perda auditiva aguda. Ao exame físico encontrava-se normal, exceto por perda auditiva bilateralmente. Os exames laboratoriais demonstraram leucocitose importante (645.000), com 66,4 por cento de blastos com características mielóides, 13,6 por cento bastões, 15,3 por cento segmentados, 1,4 por cento linfócitos, 3,3 por cento eosinófilos e plaquetas de 225.000. Devido à suspeição de leucemia com risco elevado para síndrome de hiper-viscosidade, o paciente foi admitido para tratamento na unidade de terapia intensiva. Realizado mielograma e biópsia de medula óssea que confirmaram o diagnóstico de leucemia mielóide crônica. Iniciadas hidratação, hidroxiuréia, alopurinol e dexametasona. A leucoaferese foi realizada uma semana após a admissão, quando a contagem leucocitária estava em torno de 488.000. Dez dias após o procedimento, o paciente não apresentou melhora da audição, apesar da leucometria de 10.000. Recebeu alta hospitalar em duas semanas para continuidade do tratamento ambulatorial. CONCLUSÕES: As freqüências das manifestações sensitivas em pacientes com leucemia incluem além das perdas auditiva e visual, vertigem, paralisia facial e infecções. A síndrome de hiper-viscosidade decorrente...

BACKGROUND AND OBJECTIVES: Hyperleukocytosis (> 100 x 10(9)/L) is an uncommon presentation of chronic leukemias and it can present clinical symptoms of hyperviscosity syndrome. Hearing loss and blindness rarely occurs in patients with leukemia; however, it can be strong association with hyper-viscosity syndrome. The purpose of this paper is to report a case of acute hearing loss as the initial manifestation of acute leukemia and hyper-viscosity syndrome and also mainly aspects of the intensive care treatment. CASE REPORT: A 41 year-old, male patient, who has been complaining about dizziness for six months with no response to symptomatic medications, was admitted to the emergency department with acute hearing loss. The physical examination was normal except for a bilateral hearing loss without an apparent cause. Laboratory exams showed total leukocyte: 645.000 with 66.4 percent blasts, hemoglobin: 7.0, hematocrit: 20.5, urea: 94, creatinine: 1.59, K: 5.6, Na: 138, INR: 1.38, TTPa: 0.89, troponin lower than 0.2, CK: 218, CKMB: 50, uric acid: 11.1. After a first hypothesis of leukemia with a high risk of hyper-viscosity complications, the patient was admitted to the Intensive Care Unit for monitoring and treatment. A bone marrow biopsy was performed and than started hidratation, hydroxyurea, allopurinol, dexamethasone. According to hematologists the patient had a chronic myeloid leukemia. Leukopheresis was performed one week after admission when total blood leukocytes were around 488.000. Ten days after the procedure the patient had no improvement of the hearing loss but total leukocytes were 10.100. He was discharge to the ward and 2 weeks later went home to continue ambulatory treatment. CONCLUSIONS: The frequency of sensitive manifestations in patients with leukemia include not only visual and hearing loss but also many others manifestations such as conductive vertigo, facial palsy and infections. Hyperviscosity syndrome due to hyperleukocytosis...