Flashcards in Acid-base Regulation Deck (35)
What is an acid?
A substance that can release or donate an H+
What is a base?
A substance that can combine with or accept an H+
What is the Ka?
Acid dissociation constant
Equilibrium constant/ionization constant
The higher the dissociation constant....
The more an acid is ionized and the greater its strength
What are some strong acids?
HCl, H2SO4, H3PO4, HNO3
What are some weak acids?
Acetic acids, lactic acid, H2CO3, NH4+, H2PO4-
pKa is _____ to acid strenth.
What are some ways that acid could be produced in the body?
Metabolism -> CO2
Incomplete carbohydrate and fat metabolism -> nonvolatile acid
Protein metabolism > strong acid
The net endogenous acid production (NEAP) is found...
1 mEq H+/kg body weight
Acid production via CO2.
CO2 + H2O H2CO3 H+ + HCO3-
What are the pH regulation mechanism?
What is the first line of pH flux defense and what does it do?
Minimizes a change in pH
DOES NOT remove acid or base
What is the second line of defense and what does it do?
What is the third line of defense and what does it do?
Remove excess H+
Add new HCO3-
What is the main buffer pair?
Mixture of weak acid and conjugate base or vice verse
What is normal arterial PCO2 and [HCO3-]?
40 mmHg, 24 mmol/L
pH = 6.1 + log([HCO3-] / 0.03 x PCO2)
What is chloride shift?
HCO3- diffuses out of RBC
RBC membrane is relatively impermeable to H+
Cl- diffuses into the RBC to maintain electrical neutrality
What is the process of forming CO2 in the lungs?
H+ + HCO3- H2CO3 H2O + CO2
What is the enzyme which aid in the formation of H2CO3?
What is a titratable acid?
Number of mEq OH- needed to bring the urine pH back to the pH of blood
Presents the amount of H+ that is excreted combine with urinary buffers like phosphate or creatinine
What acid in renal acidifcation is nor titratable?
If H+ is lost in the urine it is the same as....
Adding more HCO3- to the blood
What is a simple acid-base disturbance?
Single primary cause for the disturbance
Acid addition/ alkali loss
Alkali addition/ acid loss
Respiratory acidosis with renal compensation is present when PCO2 is ____ and HCO3- is ____.
Respiratory alkalosis with renal compensation is present when PCO2 is ____ and HCO3- is ____.
Metabolic acidosis with respiratory compensation is present when PCO2 is ____ and HCO3- is ____.