Acid Base balance Flashcards
Where do we excrete most of our Hydrogen, and what does this make it?
Excrete it in the urine and it makes it VERY acidic
What are the units used to measure [H+] ions in the body?
nmol/l (nano mol per litre)
Give some examples of buffering systems?
Bicarb
Phosphate
Ammonia
Haem
What is imporatn about the bicarbonate buffering system?
You can blow CO2 off - therefore Carbonic acid (H2CO3) is removed (in the form of CO2)
What is the only limitation of the bicarbonate system?
The initial concentration of HCO3-
What is acidosis?
Increased [H+] or a process tending to cause increased [H+]
too much hydrogen ions
What is alkalosis?
Decreased [H+] or a process tending to cause decreased [H+].
What is acdiaemia?
Increased [H+]
What is alkalaemia?
Decreased [H+]
What is pCO2?
The respiratory component
What is HCO3-?
The metabolic component
What is respiratory acidosis?
Increased [H+] due to increased pCO2
What is respiratory alkalosis?
Decreased [H+] due to decreased pCO2
What is metabolic acidosis?
Increased [H+] due to decreased HCO3-
What is metabolic alkalosis?
Decreased [H+] due to increased HCO3-
When would you get respiratory acidosis?
In COPD when there is an inability to blow off CO2 affectively
When would you get respiratory alkalosis? (CHECK THIS)
In someone with pneumonia (ADD EXPLANATION)
What happens when you have too much H+, and what happens when you have too much CO2?
The lungs blow off more CO2, when you have too much CO2 the kidneys get rid of H+
What is that mechanism called?
Compensation
Describe compensation in terms of too much H+?
If the problem is too much H+, this mops up HCO3- – so need to lose CO2 to restore ratio to normal
Describe compensation in terms of too much CO2?
If the problem is too much CO2, need to lose H+ (and in the process gain/reclaim HCO3-) in order to restore ratio to normal
In metabolic disorders does respiratory compensation occur slow or fast?
Respiratory compensation will occur quickly.
Describe what happens when the body has too much CO2?
CO2 builds up as the lungs can’t get rid of it some how. So the body needs to excrete more H+ in terms of [HCO3-] in the kidneys.
Give some examples of causes of respiratory acidosis?
Choking
Bronchopneumonia
COAD
Give some examples of causes of respiratory alkalosis?
Hysterical over breathing
Mechanical over ventilation
Raised intracranial pressure
Give some examples of causes of metabolic acidosis?
Impaired H+ excretion
Increased H+ production or ingestion
Loss of HCO3-
Give some examples of causes of metabolic alkalosis?
Loss of H+ in vomit
Alkali ingestion
Potassium deficiency
In blood gases what would you look at first to identify the problem?
[H+] concentration
- Increased = acidosis
- Decreased = Alkalosis
