Since the introduction of intravenous therapy, fluids containing glucose or saline in relatively isotonic concentrations have far exceeded others in use. Within the last decade new techniques in many areas of diagnosis and treatment have required that fluids of various tonicity and viscosity be introduced into the blood stream with such rapidity or in such great volume as to preclude adequate d...

There is an association between obesity and rheological blood behavior [2, 4–7]. In this sense we have read with interest the recently published article by Brun et al. [1] in this journal. The authors evaluate, in a population of 430 subjects, the relationship between abdominal obesity and body mass index (BMI) with blood viscosity, and conclude that both anthropometric parameters are associate...

Results: A total of 33 undergraduates were studied. The hematocrit, plasma viscosity and plasma fibrinogen were significantly higher in smokers than non-smokers (P < 0.01). Postexercise plasma viscosity was significantly higher than pre-exercise value in non-smokers (P < 0.0001). Hematocrit, plasma viscosity and plasma fibrinogen were also significantly higher post-exercise in smokers (P < 0.01...

Polycythemia is defined as a venous hematocrit above 65%. The hematocrit in a newborn peaks at 2 h of age and decreases gradually after that. The relationship between hematocrit and viscosity is almost linear till 65% and exponential thereafter. Increased viscosity of blood is associated with symptoms of hypo-perfusion. Clinical features related to hyperviscosity may affect all organ systems. N...

Background: There are controversial reports about the exact mechanisms of lead-induced hypertension, but many factors such as alteration in the responsiveness of cardiovascular system to endogenous substances including catecholamines could be one of the mechanisms involved. In present study, the effect of exposure to 100 ppm lead acetate by drinking water (in the periods of 4, 8 and 12 weeks)...

Severe elevation of red blood cell number is often associated with hypertension and thromboembolism resulting in severe cardiovascular complications. However, some individuals such as high altitude dwellers cope well with an increased hematocrit level. We analyzed adaptive mechanisms to excessive erythrocytosis in our transgenic (tg) mice that, due to hypoxia-independent erythropoietin (Epo) ov...

BACKGROUND Extracorporeal circulation (ECC) can induce alterations in blood viscoelasticity and cause red blood cell (RBC) aggregation. In this study, the authors evaluated the effects of pump flow pulsatility on blood viscoelasticity and RBC aggregation. METHODS Mongrel dogs were randomly assigned to two groups: a nonpulsatile pump group (n=6) or a pulsatile pump group (n=6). After ECC was s...

Experimental and computational studies were performed to elucidate the role of turbulent stresses in mechanical blood damage (hemolysis). A suspension of bovine red blood cells (RBC) was driven through a closed circulating loop by a centrifugal pump. A small capillary tube (inner diameter 1 mm and length 70 mm) was incorporated into the circulating loop via tapered connectors. The suspension of...

The blood serum rheological properties can open the door to many investigators to find the convenient therapy for many cases of radiation exposure. The present study aimed to investigate the rheological properties of rat blood serum at wide range of shear rates after whole body irradiation with 75Gy gamma radiation dose in vitro. Thirty healthy male Wistar-Kyoto rats weighing 200 gm were used i...

We measured mean afferent arteriolar diameter and renal blood flow with microsphere techniques in awake rats 24 hours after induction of acute renal failure by glycerol injection. Renal blood flow, mean arterial pressure, and total renal vascular resistance in rats with acute renal failure were not different from control levels, despite significantly elevated serum urea nitrogen. Mean afferent ...