MOD 16 - Acid-Base Homeostasis Flashcards
what is the total amount of CO2 being produced per day
25mol/day
what is the total amount of plasma [H+] produced per day?
40nmol/L
what is the total amount of unmetabolised acids produced per day?
50mmol/day
what are some of the buffering systems in place?
haemoglobin, bicarbonate, phosphate, proteins, ammonia, misc organic acids
what is the reference range of pH in the human body
7.45-7.35
what is the henderson-hasselbalch equation?
H+ + HCO3- = H2CO3 = CO2 + H20
where are the sites of acid-base metabolism?
lungs, kidney, liver, GI tract
what happens to CO2 after it is taken into the haemoglobin?
it is broken down by enzymes into bicarbonate and H+ ions - H+ ions will combine with haemoglobin
where is bicarbonate reclaimed?
it is done in the renal tubule using Na+/H+ pump where bicarbonate is converted into CO2 and reabsorbed
what hormone control the buffering level of H+ ?
aldosterone
what is secreted from the pancreas in order to reduce the H+ effect from the stomach?
HCO3-
what does the liver do in terms of buffering
dominant site of lactate metabolism, only site of urea synthesis
what is the main job of the liver in term of urea production?
combin NH4+ and CO2 to give urea and H+
what will happen if severe liver failure take place
metabolic alkalosis, NH4+ toxicity
what are the 4 different types of acidosis and alkalosis?
metabolic acidosis, metabolic alkalosis, respiratory acidosis, respiratory alkalosis
what will happen to the H+, pCO2 & pO2 in metabolic acidosis
increase H+
increase pO2
decreased pCO2
why does the pCO2 decreased and pO2 increased in metabolic acidosis
Compensate by trying to breathe out CO2 so it decreases and O2 increases- tachyponea- pink puffer
what will happen to the H+, pCO2 & pO2 in metabolic alkalosis
decreased H+
increased pCO2
decreased pO2
what will happen to the H+, pCO2 & pO2 in respiratory acidosis
increased H+
increased pCO2
decreased pO2
what will happen to the H+, pCO2 & pO2 in respiratory alkalosis
decreased H+
decreased pCO2
increased pO2
what can cause respiratory acidosis
CO2 retention - inadequate ventilation, parenchymal lung disease, inaqequate perfusion
