Chapter Intro

Plasma Composition

• Proteins in blood: albumin, fibrinogen, globulin
• Albumin contributes the most to plasma's colloidal osmotic pressure (c.o.p.)

Capillary Wall Transport

• Capillaries are not permeable to plasma proteins --> creates colloidal osmotic pressure (c.o.p.)
• C.o.p. opposes hydrostatic pressure
• C.o.p. "holds" water in plasma
• Hydrostatic pressure "pushes" water out

• Edema can be caused by:
• 1. Increases in hydrostatic pressure (e.g. traveling long hours)
• 2. Decreases in c.o.p (oncotic) pressure (e.g. low protein production)
• 3. Increases in capillary permeability
• 4. Decreases in lymphatic drainage (e.g. accidental damage to lymphatics during cancer surgery)

Blood Cells

• All blood cells are derived from hematopoietic stem cells
• Location of blood production varies throughout life
• Red Blood Cells:
• No nuclei, no organelles, survive 120 days
• NOTHING can increase their lifespan
• Erythropoietin (EPO) (produced by kidney) stimulates its production in response to low oxygen
• stimulates proliferation of erythrocyte progenitor cells AND their differentiation into mature RBCs
• Have hemoglobin to carry oxygen
• Can increase RBC production:
• High altitude
• Lung problems
• Exercise
• Taken out of circulation by macrophages --> production of pigmented molecule bilirubin
• Too much bilirubin in blood = jaundice
• Bilirubin goes into bile
• Platelets:
• Derived from megakaryocytes
• Survive 7-10 days
• No nucleus, many granules

Blood Disorders

• Anemia = decreased ability of blood to carry oxygen to tissues
• Look at hemoglobin amount, RBC count, hematocrit
• Causes:
• Decreased production of RBCs
• Iron deficiency: hypochromic, microcytic RBCs
• Aplastic anemia (bone marrow failure): normal looking RBCs
• Low EPO: normal looking RBCs
• Improper maturation of RBCs
• Vitamin B12 deficiency (aka pernicious anemia): impaired DNA production = macrocytic, normochromic RBCs
• Folic acid deficiency: impaired DNA production = macrocytic, normochromic RBCs

• Polycythemia = increased amount of RBCs
• Causes blood to be sluggish and viscous = bad
• Can be normal = physiological
• Living at high altitude
• Athletes
• Chronic lung problems (i.e. from smoking)
• Can from disease = pathological
• Tumors producing EPO
• Bone marrow disease

Hemostasis

• Process to stop bleeding
• Primary Hemostasis
• Platelet plug formation (white thrombus)
• Secondary Hemostasis
• Clotting cascade to stabilize clot (red thrombus) --> end goal is fibrinogen converted to fibrin (can be further crosslinked by F XIIIa)
• Can be activated by intrinsic and extrinsic (faster) pathways
• Platelets also involved, but not main "stars"
• Requires Ca2+/phospholipid, and vitamin K at for certain factors
• Problems:
• In primary hemostasis
• low platelets or platelets not functioning well
• Aspirin
• In secondary hemostasis
• issues with clotting factors --> low production of factors, low vitamin K, anti-coagulant drugs, liver disease