Blood Physiology Overview

Blood Physiology

• Homeostasis is the system of coordinated reactions that maintains constant internal conditions.
• Blood function due to antibodies and phagocytic activity of white blood cells is defense function.
• Respiratory function of blood is provided by hemoglobin.
• Blood acts as a humoral link during autoregulation of body function.
• Peripheral blood, blood formation, and destruction organs, and humoral regulation are included in G.F. Lang's 1939 blood system conception.
• Total blood volume in adult males is relatively 40-50% of body mass.
• Erythron includes peripheral blood, blood formation and destruction organs, and neurohumoral regulation.
• Hematocrit ratio characterizes the volume ratio of blood formed elements and plasma.

Blood Forme Elements

• Hematocrit ratio in patients can be up to 60%.
• Plasma volume is 3L if total blood volume is 5L and hematocrit ratio is 40%.
• Average blood volume per 1 kg body weight is 77 ml/kg in males.
• Average blood volume is 77 ml/kg in females.
• 45-50% of total blood volume is depot at rest.
• Total amount of protein in blood plasma is 37-45 g/L.
• Blood plasma oncotic pressure decrease if albumin level fall without change in total protein content.

Fluid and Proteins

• Blood plasma and interstitial fluid differ mainly in the sodium potassium and protein content.
• Buffering protein properties decrease blood hydrogen ion concentration.
• Blood plasma proteins generate osmotic pressure.
• Normal electrophoretic distribution of blood proteins: albumin (67.2%), a₁-globulin (3.9%), a₂-globulin (7.5%), β-globulin (12.1%), y-globulin (7.3%) and fibrinogen (2%).
• Blood replacement solutions include: albumins, solved glucose, physiological solutions, platelet mass, RBC suspension, disintoxicants, trophical solutions.
• Iron transport is provided by plasma protein transferrin.
• Vitamin B12 transport is provided by transcobalamine II.

Blood Cell Types and Ratios

• Red blood cell count for men: 4.0-5.0 *10^12/L.
• Red blood cell count for women: 3.9-4.7 *10^12/L.
• Acanthocytes, stomatocytes, and meniscocytes have abnormal shape.
• Normal red blood cell is discocyte.
• Red blood cells are negatively charged.
• Aggregation of erythrocytes is agglutination and sedimentation, reversible clumping of erythrocytes, erythropoiesis, and irreversible clumping of erythrocytes.
• Erythropoiesis is stimulated by increased hemopoietic factor production by stromal cells of bone marrow, hypoxia, and augmented secretory activity in interstitial renal cells.
• Renal response to oxygen deficiency is increased erythropoietin release.
• Blood dilution solution for counting chamber is 3% sodium chloride and 5% acetic acid + methylene blue.
• Erythrocyte sedimentation rate (ESR) increased if plasma contains high-molecular weight proteins like globulins or fibrinogens.
• Carboxyhemoglobin is a hemoglobin compound with CO.
• Normal white blood cell count is 4-9 *10^9/L.
• Neutrophil percentage is 40-65%.
• Lymphocyte percentage is 19-37%.
• Basophil percentage is 0.5-1%.
• Eosinophil percentage is 1-5%.

Physiology and Regulation

• Hemoglobin is important because it is responsible for oxygen transport rather than remaining dissolved in the plasma.
• Normal hemoglobin concentration in women is 120-140 g/L.
• Normal hemoglobin concentration in men is 130-160 g/L.
• Physiological leukocytosis is caused by thermal, miogenic, dietary, or emotional factors.
• Blood contains components whose purpose is to maintain acid-base balance and osmotic pressure.
• Some factors that maintain acid-base balance in blood plasma include osmotic pressure, buffer systems, and ions and nutrients.
• Respiratory alkalosis usually develops during activation of breathing.
• Bicarbonate, phosphate, and hemoglobin are important buffer systems in blood.

Blood Coagulation

• Apoptosis is a physiological process that results in programmed cellular death and is essential to maintaining homeostasis in the body.
• Phagocytosis is the process of engulfing a solid particle by a phagocyte.
• Diapedesis is the process of outward passage of leukocytes through intact vessel walls.
• Thromboxane causes platelet aggregation and vasoconstriction, and it is a product of arachidonic acid metabolism.
• Von Willebrand factor is a large multimeric glycoprotein involved in platelet adhesion.
• In vascular damage, a cascade of reactions occurs leading to clot retraction.
• Clot retraction involves the shrinking of a blood clot dependent on the release of multiple coagulation factors from platelets.
• Blood coagulation includes multiple substances that work in conjunction during this process.
• White blood cells count and formula are good indicators for measuring blood disorders.

Blood Groups and Transfusion

• Blood types are important for considerations in transfusions.
• Blood group I can receive any type
• Blood group II can receive I, II
• Blood group III can receive I, III
• Blood group IV can receive I, II, III, IV
• Blood groups contain different antigens and antibodies that determine compatibility for blood transfusions.
• Incompatible blood transfusion can cause severe reactions.

Explore the critical functions and components of blood in this quiz. Learn about homeostasis, blood formation, and the role of blood in defense and respiration. Test your understanding of hematocrit ratios and blood volume concepts.