![]() ![]() Increased viscosity increases the resistance to blood flow and thereby increases the work of the heart and impairs organ perfusion. In fact, increasing the hematocrit from 40 to 60% (a 50% increase) increases the relative viscosity from 4 to 8 (a 100% increase). Patients with an abnormal elevation in red cell hematocrit (polycythemia) have much higher blood viscosities. At a normal hematocrit of 40%, the relative viscosity of blood is about 4. Therefore, blood viscosity strongly depends on hematocrit. Note that the increase is non-linear increased hematocrit causes a disproportionate increase in relative viscosity. Increasing red cell hematocrit increases relative viscosity. In the figure, the relative viscosity at 0% hematocrit (plasma without cells) is about 1.8 as shown by the y-intercept. Of these formed elements, red cells have the greatest effect on viscosity. The addition of formed elements to plasma (red cells, white cells, and platelets) further increases the viscosity. In fact, plasma at 37☌ is about 1.8-times more viscous than water at the same temperature therefore, the relative viscosity (ηr) of plasma compared to water is about 1.8 3. Because of molecular interactions between these different components of plasma, it is not surprising that plasma has a higher viscosity than water. Whole blood viscosity is the sum of plasma viscosity (mainly determined by colloid components such as albumin) plus the density and packing of all blood cells and their rigidity (see Figure 1) 2. Blood viscosity is determined by plasma viscosity, hematocrit (volume fraction of red blood cell, which constitute 99.9% of the cellular elements), red blood cell deformability, mechanical properties of red blood cells, red blood cell aggregation, and plasma viscosity.Īlthough plasma is mostly water, it also contains other molecules such as electrolytes, proteins (especially albumin and fibrinogen), and other macromolecules. ![]() Normal serum viscosity relative to water is 1.4 to 1.8 cp 1. Viscosity is measured in the unit of centipoise (cp). Viscous blood are thicker and travel more slowly. When blood has low viscosity, it travels quickly and without much difficulty. Viscosity is formally defined as the measurement of the internal resistance of a fluid to flow but can simply be thought of as the “thickness” or “stickiness” of a fluid. Proper management of any ongoing illnesses, along with input from a blood specialist, are the best ways to limit complications from this condition.Blood viscosity is the thickness or stickiness of blood. In adults, hyperviscosity syndrome is often related to an underlying medical problem. These complications can include:īe sure to report any symptoms your baby is having to their doctor right away. This is generally the result of a lack of blood flow and oxygen to the brain and other vital organs.Ĭontact your baby’s doctor if you notice any changes in your infant’s behavior, feeding patterns, or sleeping patterns.Ĭomplications may occur if the condition is more severe or if your baby isn’t responding to treatment. Some children who’ve been diagnosed with this syndrome have developmental or neurological problems later on. If the cause is related to a genetic or inheritable condition, it may require long-term treatment. There’s a good chance for full recovery, especially if the cause appears to temporary. If your baby has a mild case of hyperviscosity syndrome and no symptoms, they may not need immediate treatment. Normal values are usually between 1.6 and 1.9.ĭuring treatment, the goal is to lower viscosity to the level needed to resolve an individual’s symptoms. In adults, hyperviscosity syndrome typically causes symptoms when blood viscosity is between 6 and 7, measured relative to saline, but it can be lower.
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