Exam 4: Wed 11/11 blood review Flashcards
Function of the Red Blood Cells AKA Erythrocytes (3)
- Transport hemoglobin - O2 carrier
- Transport enormous quantities of CO2 in the form of bicarbonate ion (HCO3−) away from the tissues to the lungs
- RBCs responsible for most of the acid-base buffering power of whole blood
True or false: Hemoglobin sucks at trying to be an acid-base buffer
False
- Hemoglobin in the cells is an excellent acid-base buffer
- True of most proteins
- Binds H+
What is the concentration of Red Blood Cells in the Blood?
- In normal men, the average # RBCs 5,200,000/m3 & in normal women, it is 4,700,000/m3
- Persons living at high altitudes have greater numbers of red blood cells
- Natural, “legal” blood doping
What is the quantity of Hemoglobin in the RBCs?
- Hemoglobin in RBCs =34 grams/100 ml of cells which is the metabolic limit of the cell’s hemoglobin-forming mechanism
- Whole blood has average of 14-15 grams of hemoglobin/100 ml
- Lab norms: Hgb male 14-18; Hgb female 12-16
- Millions Hb or Hgb molecules per RBC
- Each gram of pure hemoglobin is capable of combining with 1.34 ml of O2
*Hematocrit (% of blood that is RBCs) - normally 40-45%
Where are RBCs produced?
- exclusively in the bone marrow
- Basically all bones produce red blood cells until a person is 5 years old
- Marrow of the long bones, except proximal portions of the humerus and tibia, becomes quite fatty; produces no more red blood cells after about age 20 years.
- Beyond this age, most RBCs continue to be produced in the marrow of the membranous bones, such as the vertebrae, sternum, ribs, and ilia.
Two reasons RBCs # regulated within narrow limits
- Adequate number of RBCs available to provide sufficient transport of oxygen from the lungs to the tissues
- Not too many, so cells do not impede blood flow (would thicken the blood)
What are the causes for a decrease in O2 transported to tissues which in turn increases the rate of red blood cell production?
Dr. T has 4 bullet points listed under this heading
- Hemorrhage
- Destruction of major portions of the bone marrow
- High altitudes
- diseases of the circulation that decrease blood flow through the peripheral vessels & failure of blood oxygen absorption in the lungs
What is Erythropoietin (EPO)?
a hormone secreted by the kidneys that increases the rate of production of red blood cells in response to falling levels of oxygen in the tissues.
Some things to know about erythropoietin and its role in the regulation of RBC production (4)
- Principal stimulus for red blood cell production in decreased O2 states
- About 90% of all erythropoietin is formed in the kidneys with rest formed mainly in the liver
- Norepinephrine, epinephrine and several of the prostaglandins increase erythropoietin production
- End Stage Renal Disease (kidney failure) patients have only 33-50% RBCs due to only 10% of the normal erythropoietin
3 key roles of leukocytes
- Immune response: Innate – polymorphonuclear granulocytes & monocytes, Acquired - lymphocytes
- Inflammation
- Allergic reactions
4 things to note about neutrophils
- Most numerous of WBCs accounting for 55-70% of WBCs
- Phagocytic
- First on scene in infection or injury
- Short-lived and self-destruct after eating harmful antigens
Two things to note about lymphocytes
- 30-40% of WBCs
- Make up B cells, T cells, and NK cells
Three things to note about monocytes
- 3-8% of WBCs
- Macrophages - phagocytic activity
- Secretion of cytokines which stimulates the attraction of other phagocytes
Three things to note about eosinophils
- 1-6% of WBCs
- Release of cytokines, growth factors and other enzymes/factors
- Important in parasitic infections & allergic response
Four things to note about Basophils
- Few in number - 0.01% to 0.3% of WBCs
- Secrete the following substances: heparin, histamine, serotonin, kinins, leukotrienes , prostaglandins & Platelet activating factor
- Potentiates other vasoactive substances &inflammatory mediators
- Assists in regulation of blood clotting
What does plasma do?
carries antibodies and nutrients to tissues, removes wastes
Common causes of blood problems/disorders that you may encounter as a PT (4)
- Use of NSAIDs
- Neurological complications from pernicious anemia
- Complications of chemotherapy and radiation
- Orthopaedic blood disorders are usually either bleeding (hemostasis) or clotting (hypo- or hypercoagulation disorders)
Where are the platelets and coagulation factors in the blood?
Plasma
What might we assume if someone has blood issues?
They have oxygen issues
Signs and symptoms of hematologic disorder
listed by Dr. T (5)
and I’m adding some from Goodman and Fuller (4)
- Exaggerated response to minimal exercise (dyspnea, chest pain, palpitations, severe weakness, fatigue)
- Neurological symptoms (headache, drowsiness, dizziness, syncope, polyneuropathy)
- Skin and fingernail bed changes (cyanosis, clubbing)
- Easy bruising
- Swelling, pain in joints
Goodman and Fuller
- congestion (accumulation of excessive blood w/in vessels in tissues/organ)
- edema (lymphedema, pulmonary, ect..)
- infarction (heart, brain, kidney, ect..)
- shock (weak distal pulse, hypotension, all other signs of shock)
Changes seen in the skin from hematologic disorders and their respective cause (5)
- Untreated pernicious anemia= light, lemon yellow tint
- Severe anemia resulting from acute hemorrhage= white,waxy appearance
- Chronic blood loss= gray-green yellow
- Leukemia= gray tint
- Anemia= pale hands or palmer creases
Changes seen in the nail bed from hematologic disorders and its respective cause
Long-standing iron deficiency anemia= brittle and/or convex (rather than concave)