Carriage Of Oxygen And Carbon Dioxide In The Blood Flashcards
What are the 3 ways co2 is carried and what percentages
Dissolved 10%
Reacted with water -> hco 3 60%
Bound to haemoglobin 30%
Why is oxygen dangerous?
Oxidises things
How does the body protect against the oxidising effect of oxygen
Carried by hb
What are the 2 sorts of rbc anaemia?
Macrocytic or microcytic
What is how much hb in rbc called?
Mean corpuscular haemoglobin concentration mchc
How does vitamin c protect against oxidation?
Redonates electrons
What is haematocrit
Rbc vol : total blood vol
What is too high haematocrit called
Polycythaemia
How does glucose enter rbc
GLUT1 transporters
What is special about glut 1 transporters
Non insulin dependent
What’s the ultimate end of glutathione deficiency
Too much methaemoglobin when under oxidative stress
What is methaemoglobin
Iron ii is fully oxidised to iron iii
What can cause oxidative stress
Fava beans
Trimethoprim
Sepsis
Why did trimethoprim cause oxidative stress
Contains sulphur
What is trimethoprim
Antibiotic for UTI, occasionally chest infection
What are the symptoms of too much methaemoglobin
Jaundice
Dark urine
What prevents fe2 being fully oxidised and what’s it called
Histidine protein under porphyrin ring
Steric hindrance
What is the difference between hypoxia and hypoxaemia
Hypoxia - tissues
Hypoxaemia - blood
What is the diagnosis when there is hypoxia without hypoxaemia and why?
Anaemia. All hb sites are occupied but not enough of them
What pressure is respiratory failure
<8kpa
What happens enzymatically in anaemia
2, 3 DPG lowers hb affinity for oxygen thus S curve shifts to the right and more oxygen is released
What do the kidneys do when there is hypoxia
Release erythropoietin
What stimulates more rbc to be made
Erythropoietin
Where is the concentration of hco3 controlled
Kidneys
