Acid-base and Blood Gases Flashcards
What happens in an oxygen deficit?
Haemoglobin gives up O
Takes in CO2
HCO3- given up + exchanged for Cl-
What happens when its oxygen rich?
Large shunt of O into RBC
High affinity for O
CO2 out = gives up H+
Cl- exchanged for HCO3-
What happens if there is an injury in the lungs?
Acute problem = chest can’t respond fast = can’t get rid of gas = RBC becomes saturated
What normal metabolic processes are involved in the production of hydrogen?
Digestion of food
Metabolism of drugs
Errors with within metabolism
Which organ is responsible for the secretion of hydrogen?
Kidney
Why can anaerobic metabolism produce H?
Produces lactate = an acid = H+
How is CO2 produced?
Oxidative metabolism
How is CO2 excreted?
By ventilation
What is the normal pH within the body?
7.35-7.46
Describe renal filtration
1. maintain acid-base balance
Na+ + HCO3- filtered in glomerulus
Renal tubule cells secrete H+ in exchange for Na+
CO2 is formed by reaction of H+ + HCO3- + diffuses into tubule cell = impermeable to bicarbonate
CO2 converted back to HCO3- in cell
Na+/HCO3- symporter carries Na+ + HCO3- across membrane
What do renal cells do?
Secrete H+ in exchange for Na+
Describe renal filtration
2. maintain acid-base balance
Na+/H+ antiport secretes H+
H+ in filtrate combines with filtered HCO3- to form CO2 + H2O
CO2 diffuses into cell + combines with H2O to form H+ + HCO3-
H+ is secreted again + excreted
HCO3- is reabsorbed
Glutamine is metabolised to ammonium ion + HCO3-
NH4+ is secreted + excreted
HCO3- is reabsorbed
What are buffering systems in intracellular fluid?
Phosphate buffer system
Protein buffer
What are buffering systems in extracellular fluid?
Protein buffer
Carbonic acid-bicarbonate system
What is involved in protein buffering system?
Haemoglobin
Amino acid (all proteins)
Plasma protein