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.

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.

Bernoulli, Poiseuille, Pascal y la energética de la circulación sanguínea / Bernoulli, Poiseuille, Pascal and the energetics of the circulation

La sangre fluye desde un sitio de mayor energía a otro de menor energía y no necesariamente desde un sitio de mayor presión a otro de menor presión como frecuentemente se asevera. Existen varios ejemplos en la circulación sanguínea que demuestran esta aseveración, pero su comprensión requiere del conocimiento básico de las ecuaciones de Bernoulli, Poiseuille y Pascal lo cual se intenta entregar en este artículo. La ecuación de Bernoulli es la ecuación básica que describe los componentes de energía que la contracción ventricular imparte a la sangre durante la eyección y en que la energía de presión es sólo uno de esos componentes, además de la energía cinética y de la energía potencial gravitacional. La ecuación de Poiseuille aporta a lo anterior el componente de viscosidad, el cual induce resistencia al flujo y pérdida de energía de presión para mantener el flujo. Finalmente el principio de Pascal explica la aparente paradoja de la dirección del flujo en contra de un gradiente de presión con los cambios posturales.

Blood flows from a site of high energy to a site of low energy and not necessarily from a site of high pressure to a site of low pressure as usually asserted. Several examples in the circulation support this view, however its understanding requires a basic knowledge of Bernoulli, Poiseuille and Pascal equations which is the purpose of this report. Bernoulli equation is the basic equation that describes the different energy components that the ventricular contraction imparts to the blood and of which pressure is just one of them besides kinetic and potential gravitational energies. Poiseuille equation supplies the viscous component that induces resistance to flow and dissipates pressure energy to maintain flow. Finally, Pascal principle provides the explanation for the direction of flow against a pressure gradient in the erect position.

Reacción fisiológica de la hemodilución isovolémica aguda en pacientes en edad escolar / Physiological reaction to acute isovolemic hemodilution in school-age children

La hemodilución isovolémica aguda (HIA) es un procedimiento utilizado para el ahorro de sangre homóloga en cirugía electiva. Al disminuir el hematocrito, disminuyen las resistencias periféricas totales y se incrementa el gasto cardíaco (Qt). Objetivo: El objetivo principal fue conocer la reacción fisiológica de la HIA aplicada a cirugía electiva de niños en edad escolar. Material y método: Se realizó un estudio descriptivo, longitudinal y prospectivo en niños en edad escolar que cubrían los criterios de inclusión. Se analizó el Qt y la oxigenación sistémica en cuatro fases mediante ANOVA de medidas repetidas y T pareada con una p < 0.05. Se utilizó como solución de reemplazo polimerizado de gelatina al 3.5 por ciento en una proporción de 1.5 ml/1 ml de sangre. Resultados: Se evaluaron 15 pacientes (n = 15), todos considerados como ASA I, de edad x = 11 años ± 1.25. Se realizó una flebotomía de x = 1116.67 ml ± 95.74. Se comprobó un incremento del Qt, de la PVC y de la O2ER, y una caída de las RPT, RVS y del hematocrito, observándose diferencias estadísticamente significativas durante las fases 2 y 3. La FC y PAM se mantuvieron uniformes durante todo el procedimiento. Se obtuvo un ahorro de sangre homóloga del 100 por ciento. Conclusiones: Se obtuvo una adecuada respuesta fisiológica a la HIA en los pacientes en edad escolar estudiados, por lo que se puede proponer a la HIA como una técnica alternativa de ahorro de sangre homóloga.

The effect of aerobic exercise on blood and plasma viscosity on cardiac health club participants.

AIM: to analyze the effect of SJS aerobic exercise on blood and plasma viscosity. METHODS: the study was performed on 30 subjects with an age span of 40 to 60 years. Subjects participated in SJS aerobic exercise of moderate intensity of 40 to 45 minutes duration, three times a week for 9 to 12 weeks. Five milliliters of blood were collected into K3EDTA container to assess blood and plasma viscosity prior to the program and following the completion of the SJS program. Blood and plasma viscosity was measured using Brookfield LVDV-III viscometer using rotational method principle. RESULTS: this study demonstrated a significant decrease in blood viscosity (2.94%, p = 0.03) and insignificant decrease in plasma viscosity in subjects following SJS aerobic exercise compared to prior exercise. CONCLUSION: this study proved that SJS aerobic exercise of moderate intensity of 40 to 45 minutes duration times a week for 9 to 12 weeks gave the benefit of lowering blood viscosity, which contributes to reducing the risk of coronary heart disease.

Evaluación de alteraciones hemorreológicas en pacientes hipertensos / Hemorheological alterations in hypertensive patients

El objetivo de este trabajo fue investigar el perfil de viscosidad sanguínea y evaluar la influencia de factores plasmáticos ( fibrinógeno) y celulares ( agregación eritrocitaria ) en un grupo de pacientes hipertensos comparados con un grupo de paciente normotensos. Se trabajó con sangre anticoagulada de pacientes hipertensos no diabéticos (n=3) e indivíduos sanos (n=40). La viscosidad plasmática y de sangre entera se determinaron con un viscosímetro cono-plato. La agregación eritrocitaria se estudió por observación microscopia de los agregados y cuantificación a través de un parâmetro de forma denominado ASP ( Aggregation Shape Parameter), definido como la relación de área proyectada respecto al perímetro. El fibrinógeno se determino con un coagulómetro por el método de Clauss. Los valores de viscosidad de sangre entera resultaron significativamente aumentados en los pacientes hipertensos respecto de los normales para todas las velicidades estudiadas. Los valores de viscosidad plasmática solo presentaron diferencia significativas a bajas velocidades de corte (1.15 a 11.56 seg •1) . Los pacientes hipertensos presentaron agregados amorfos e irregulares, lo que se refleja en los valores alterados de ASP, significativamente mayores (p<0.001) en paciente hipertensos (0.69± 0.11) respecto de los indivíduos normales ( 0.25± 0.12). Los valores de fibrinógeno resultaron ligeramente superiores en los pacientes hipertensos respecto del grupo control (p< 0.01). Numerosos parámetros hemorreológicos juegan un papel importante en la patogénesis de la hipertensión. Entre estos factores hemorreológicos, valores parâmetros podrían estar en la hipertensión ( hematrocito, fibrinógeno plasmático, deformabilidad y agragación eritrocitaria , viscosidad sanguínea y plasmática). En este trabajo, se pudo demostrar anormalidades en la agregación eritrocitaria, detectada por los valores de ASP que podría estar involucrado en las complicaciones vasculares de la hipertensión.

Paraproteins: a regional South Australian experience.

We have performed a systematic review of all new serum and urinary paraproteins detected over a six year period in an immunodiagnostic laboratory serving a population of 400,000 people. Clinical diagnoses and associated laboratory features were ascertained from a computerized laboratory database or from clinical notes. Over the period of study, serum or urine paraproteins were detected in 613 new patients. These consisted of 568 patients with serum paraproteins and 45 patients with urinary monoclonal free light chain (in the absence of a serum paraprotein). These paraproteins occurred more commonly in males and the frequency increased with age. Approximately 30% of the serum paraproteins and 60% of urinary monoclonal free light chain were associated with B cell lymphoproliferative disorders (multiple myeloma, plasmacytoma, Waldenstrom's macroglobulinemia, non-Hodgkins lymphoma, chronic lymphocytic leukemia, etc) with the remainder being labeled as monoclonal gammopathies of uncertain significance (MGUS). At clinical presentation, patients with lymphoproliferative disorders tended to have higher levels of paraprotein, B2 microglobulin, the presence of free urinary light chain and demonstrated molecular size heterogeneity of the paraprotein but there was considerable overlap. A good correlation was noted between paraprotein concentration and viscosity in most patients. In conclusion paraproteins were most frequently encountered in the context of a gammopathy of uncertain significance. Features which suggested lymphoproliferative disorders included higher levels of serum paraprotein (> 15 g/l), elevated levels of B2-microglobulin and the presence of urinary free high chain. However, as much overlap was seen with patients with MGUS, regular monitoring of paraprotein level is considered mandatory in the management of these patients.

The influence of persistent hyperglycaemia on hyperfibrinogenaemia and hyperviscosity in diabetes mellitus

The effect of hyperglycaemia on hyperfibrinogenaemia and its consequence on plasma viscosity was investigated in 69 diabetic patients during the course of hypoglycaemic treatment. Glycaemic control was assessed by measurement of glycosylated haemoglobin (HbA1). Plasma fibrinogen concentration (PFC) was determined by a clot-weight method. The relative plasma viscosity (RPV) was measured by capillary viscometry. The mean PFC and RPV were significantly (p < 0.001) elevated in the diabetic patients as compared with a non-diabetic control group. Both PFC and RPV showed a distinct, step-wise increase with progressively poorer glycaemic control. The data strongly indicate that persistent hyperglycaemia is associated with a frank hyperfibrinogenaemia and hyperviscous plasma in most of the diabetic patients studied. These abnormal haemorrheological changes could impact adversely on both the haemostatic process and circulation in diabetic patients.

Estudio de las propiedades reológicas de la sangre durante la conservación / The study of the blood rheologics properties during its storage

Por medio de los parámetros viscoelásticos in vitro se estudiaron las alteraciones reológicas producidas durante el almacenamiento de eritrocitos humanos. Se estudiaron durante 35 días alícuotas semanales de globulos rojos compactados (CG) y de sangre entera (SE) almacenadas en CPD-adenina. Las muestras fueron analizadas utilizando el eritrodefórmetro en régimen estacionario y en régimen oscilante. Se midió la viscosidad sanguínea y plasmática con un viscosímetro cono/plato. La viscosidad sanguínea y el índice de deformabilidad de los eritrocitos se ven alterados con el tiempo de conservación, mostrando un pico máximo a la segunda semana de conservación. Todos los parámetros de viscoelasticidad compleja se modifican también, siendo más notorias estas alteraciones para las mayores frecuencias de oscilación. Todas las determinaciones reológicas realizadas muestran alteraciones en las propiedades estructurales de los eritrocitos almacenados como concentrado globular. Estas alteraciones son menos importantes que las encontradas en la sangre entera almacenada. En consecuencia, es importante evaluar no sólo los componentes celulares sino también el plasma debido al papel predominante que tienen las proteínas plasmáticas an las alteraciones del comportamiento reológico de los eritrocitos durante su almacenamiento.

Symptomatic neonatal polycythemia: comparison of partial exchange transfusion with saline versus plasma.

A prospective study to evaluate efficacy and safety of partial exchange blood transfusion (PEBT) with normal saline or plasma was conducted in 30 symptomatic polycythemic newborns. Babies were randomly assigned to receive PEBT either with normal saline or plasma. Both groups were comparable in terms of birth weight, gestational age, preexchange hematocrit and viscosity. A significant fall in hematocrit and viscosity was noticed at 6 hours following PEBT which persisted even at 24 hours (P < 0.001). Hematocrit and viscosity were comparable in the two groups at 6 and 24 hours (p > 0.05 for both). Majority of babies became asymptomatic after 24 hours of PEBT, but one baby in the saline group remained polycythemic and symptomatic requiring repeat PEBT. No complications related to the procedure were encountered in the two groups. Partial exchange with normal saline was as effective and safe as plasma in symptomatic polycythemic newborns.

Importância da hemorreologia clínica no estudo do fluxo sanguíneo cerebral em condiçöes normais e na isquemia cerebrovascular / The importance of clinical hemorheology for the study of the cerebral blood flow in normal conditions and in cerebrovascular ischemia

É apresentada avaliaçäo crítica da importância da hemorreologia no estabelecimento da conduta terapêutica clínica na insuficiência cerebrovascular aguda. Com essa finalidade säo revistos aspectos relativos a fluxo sanguíneo cerebral, insuficiência cerebrovascular e hemorreologia clínica. Em funcçäo desses aspectos säo avaliados alguns dos principais medicamentos utilizados no presente no tratamento do acidente vascular cerebral e säo discutidas normas gerais para prevençäo e tratamento das isquemias cerebrais

Comparación de distintas soluciones para eritroferesis en la poliglobulia neonatal / Comparisson of several solutions for eritropheresis in neonatal polyglobulia

Se estudiaron prospectivamente 29 recién nacidos poliglobúlicos, que no presentaban enfermedades relevantes asociadas, asignándoles al azar a tratamiento de eritroferesis con solución NaCl 0,9 por ciento, plasma o albúmina al 5 por ciento. Se les midió hematocrito, viscocidad sanguínea y sodio plasmático antes y después de la eritroferesis. Las tres soluciones fueron igualmente efectivas en disminuir significativamente el hematocrito y la viscocidad sanguínea. En los tres grupos la disminución del hematocrito se mantuvo 12 a 24 horas después de la eritroferesis y el sodio plasmático se mantuvo estable, sin variaciones entre las cifras previas y posteriores al procedimiento. La solución de NaCl 0,9 por ciento tiene las ventajas de no ofrecer riesgos de transmitir infecciones, menor costo y no motivar objeciones religiosas, por lo que parece ser la mejor opción para la eritroféresis en recién nacidos con poliglobulia

A clinico-hematological study of iron deficiency anemia and its correlation with hyperviscosity symptoms in cyanotic congenital heart disease.

The present study was carried out in 33 cases of cyanotic congenital heart disease (CCHD) to determine the prevalence of iron deficiency anemia (IDA) and its correlation to hyperviscosity symptoms in terms of hematocrit levels. Furthermore, the study was aimed at assessing the response to low dose iron therapy (60 mg of elemental iron once daily) in relieving symptoms of hyperviscosity. All these cases were evaluated for presence of symptoms of hyperviscosity and later subjected to various hematological & biochemical parameters of iron deficiency anemia including hemoglobin (Hb), pack cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), serum iron, total iron binding capacity respectively. Results showed presence of IDA in 6/33 cases (18.2%) and hyperviscosity symptoms in 10/33 cases (30.3%). Amongst the group with symptoms of hyperviscosity, in the subset having IDA these symptoms were observed at PCV levels of 0.52 L/L to 0.58 L/L in contrast to the subset not deficient in iron where the symptoms occurred at a PCV 0.68 L/L. Relief of symptoms of hyperviscosity was evident with a minimal rise of mean hemoglobin by 2.1 gm/dl. It was concluded that IDA was not an uncommon finding in CCHD cases and that it leads to symptoms of hyperviscosity at a level of PCV much lower than those known to produce these symptoms. Finally low dose iron therapy was found effective in relieving the symptoms of hyperviscosity.

Haemorheology in diabetes.

The rheology of blood is disturbed in diabetes due to increased viscosity of blood and decreased deformability of red blood cells. This disturbed haemorheology contributes to diabetic vasculopathy and is reversible with treatment with insulin.