Topic 1 - Blood Flashcards
What is blood?
- Organ
- Made of RBC, WBC, plasma, & platelets
- Want to avoid giving blood in perfusion (goal directed perfusion)
What does blood do?
- Transport services
- Protection services
- Temperature regulation (heating from the inside-out is more uniform)
Plasma
- 54% of TBV
- 4% of body weight (1L water = 1kg water)
- 90% water / 10% solute (proteins/electrolytes/organic material)
Electrolytes
- makes up most of solute in NUMBER inside the plasma
- Ca, K, Na, Cl, Mg, HCO3
- Impulse conduction, coagulation, cardiac rhythm, fluid balance, muscle function, and acid base balance
Plasma proteins function
- Maintain osmotic pressure
- Maintain fluid balance
- Transport and carry
- Immune functions
- Enzymes
- Blood buffers
Plasma protein types
- Albumin : 62%
- Globulins (all protein except albumin and fibrinogen) : 34%
- Fibrinogen : 4%
Albumin
- Responsible for colloid osmotic pressure
- Transport free fatty acids and bilirubin
- Binds competitively with variety of drugs
Globulins
- Gamma/Immunoglobulins are of interest
- Involved with Immune system
Plasma Proteolytic Protein Systems
-Globulin functional group
-Complement system (inflammation)
-Kinin system (vasoactive effects)
-Blood Coag system
(extrinsic/intrinsic factors -> thrombin -> fibrinogen -> clotting)
-Fibrinolytic system (makes plasmin which breaks down fibrin)
Plasma Protease Inhibitors
- Globulin functional group
- Macroglobulin (inhibits plasmin/thrombin/kallikrien)
- Antithrombin III (thrombin)
- C1 inhibitor (Activiated C1/kallikrien)
- Plasmin inhibitor (plasmin)
Carrier proteins
- Globulin functional group
- Albumin
- Haptoglobin
- Hemopexin
Acute Phase Proteins
- Globulin functional group
- Involved with inflammatory response
- Interleukins recruit WBCs
- Initiates fever
Hypoproteinemia
- Protein deficiency
- Caused by : malnutrition / protein production (liver problems) / poor absorption / protein excretion / hemodilution
- Hemodilution caused by CCP….can prime ECC with albumin to help
Hypoproteinemia affects
- Acid-base balance
- Clotting mechanisms
- Enzyme dependent reactions
- Fluid Balance
- Transport problems
Hyperprotienemia
- Increased plasma proteins
- More rare than hypo
- Can cause clots in blood in microvascular
RBC Function
Carry O2 and CO2
RBC dimensions
- Biconcave discoid
- 8.1 microns in diameter
- 1.0 - 2.7 microns (thin part and thick part)
- 138 microns^2 in area
- 95 microns^3 in volume
RBC Lifecycle
- 120 days
- Stimulated by pO2
Normal pO2 that gives us 50% hemoglobin bound to O2
25 mmHg
Factors that shift Oxy-Hemo curve to right (less affinity)
- Increased PCO2
- Decreased pH
- Increase in Temp
- Increase in 2,3 DPG
Bohr affect
- How change in [CO2] affects affinity of O2/Hb
Haldene affect
- How [O2] affects CO2/Hb curve
- Opposite affect of Bohr
O2 transport
- 2% of total O2 is dissolved in plasma (forms partial pressure)
- 98% of total O2 bound to Hb inside RBC (reversible bound)
CO2 transport
Insert picture
Methemoglobin
- Formed when normal Fe2+ is oxidized to Fe3+
- Bad for body…can no longer bind to O2
- Methemoglobin reductase prevents this in RBC
Fetal Hb
- Hb F
- Higher affinity for O2 than Hb A
RBC Hemolysis
- Lysis of RBC (can activate clotting cascade)
- Caused by: immune response after transfusion / sepsis / medications / toxins / enzyme deficiency / CPB
Types of WBC
- Granulocytes (neutrophils/eosinophils/basophils)
~neutrophils big prob for perfusionist - Monocytes (become macrophages)
- Lymphocytes (B and T cells)
Neutrophils
- Little version of macrophage
- very sensitive to stimulation
- respond to bacteria
- forms pus
- removed by macrophages
- short lived
Eosinophils
- Toxic to all antigens
- function in allergic reactions
- release chemical called MBP (bad if on CPB)
Basophil
- exhibit chemotaxis….not phagocytosis
- may release histamine and heparin
- histamine = very potent vasodilator
- Basophils (in blood) –> Mast cells (in tissues)
Monocytes
- mature into macrophages
- very big relatively (12-20 microns)
Lymphocytes
- Most complex WBC
- Directs the immune system
- T cells are 75% and B cells 25%