Lecture 13- Haematology Lecture 1 Flashcards
What is blood and what are its characteristics?
Blood is a specialized bodily fluid that circulates through the vascular system, delivering essential substances such as oxygen, nutrients, hormones, and immune cells to various tissues, cells and organs throughout the body. It also plays a crucial role in removing metabolic waste products from cells, regulating body temperature, and maintaining homeostasis
charachteristics:
-more viscouse and dense than water
- pH 7.35-7.45
-colour varies with oxygen content
-accounts for~20% extracellular fluid and 8% body mass
-total volume is 5-6l in makes and 4-5l in females and is regulated by hormones
Why is blood essential to life?
Blood is a specialized bodily fluid that circulates through the vascular system, delivering essential substances such as oxygen, nutrients, hormones, and immune cells to various tissues, cells and organs throughout the body. It also plays a crucial role in removing metabolic waste products from cells, regulating body temperature, and maintaining homeostasis
What are the characteristics of blood?
charachteristics:
-more viscouse and dense than water
- pH 7.35-7.45
-colour varies with oxygen content
-accounts for~20% extracellular fluid and 8% body mass
-total volume is 5-6l in makes and 4-5l in females and is regulated by hormones
How can we get blood? What does it depend on?
using venepuncture from the median cubital vein and using a vacutainer which is colour coded to describe its contents
- Tubes are lined with additives often to prevent
coagulation, however how this is done depends
on what tests will be run later; - Heparin
- Citrate
- EDTA
- Sometimes a procoagulant tube is used to obtain
a clotted sample
How are the fluid compartments differentiated for someone who is 70kg?
- Typical 70Kg male contains 42L water (60% of total body weight)
- Average female contains 55% of her body weight as water (due to
higher fat content) - As a rule of thumb approximately 70mL blood/Kg (remains the
same for most animals)
What are the blood characteristics of plasma?
- 55% blood volume
Contains: - Low [K+] & [Mg2+]
- High [Na+] & [Cl-]
- High protein concentration
- A clear, straw-coloured liquid
- Plasma contains no cellular components
How is plasma extracted?
- Blood is taken into a tube containing an anticoagulant:
Heparin, citrate or EDTA - Centrifugation of the blood separates the cellular components from the fluid
- The fluid (plasma) is removed for analysis
How is blood differentiated between plasma and RBC?
it is withdrawn and placed in a tube that is centrifuged
What does plasma contain?
- 55% blood volume
Contains: - Low [K+] & [Mg2+]
- High [Na+] & [Cl-]
- High protein concentration
- A clear, straw-coloured liquid
- Plasma contains no cellular components
When blood is centrifuged what is it separated into and what are the percentage makeups of all the different components?
-Plasma: 55% of whole blood
-Buffy coat
-Erythrocytes: 45% of whole blood
-7% of blood plasma is proteins
-91.5% of blood plasma is water
-1.5% of blood plasma is other solutes
What are the different plasma proteins and how abundant are they in the plasma?
- Normal level of plasma proteins is 60-80g/L
- Albumin maintains osmotic pressure and
transports insoluble molecules - Globulins (α,β and g) transport ions,
hormones, & lipids → assist in immune
function - Fibrinogen – ‘molecular glue’ involved in
blood coagulation.
What are the plasma solutes?
cations-Na+, K+, Ca2+, pH 7.35-7.45
Anions- cl-, HCO3-, HPO4(2-)/H2PO4-, lactate, SO4(2-)
glucose, cholestral, amino acids, urea
oxygenated plasa:99% oxygen saturation
deoxygenated plasma:75% oxygen saturation
What are the plasma cations and how abundant are they?
cations (most to least abundant): Na+, K+, Ca2+, pH 7.35-7.45
What are the plasma anions and how abundant are they?
ations (most to least abundant): cl-, HCO3-, lactate, SO4(2-), HPO4(2-)/H2PO4-
What does a buffer system do?
absorb differences in H+ ions to bring the pH back to the normal, carbonate and phosphate are two examples of buffer salts in the blood
