A &P Acid Base Exam 1 Flashcards
physiological pH
7.4
acidosis
when pH is below 7.35
alkalosis
when pH is above 7.45
buffer
stabilizes pH by keeping the acid/base ration consistent
if concentration fluctuations are counteracted in such a way that resulting ratio is log (1) what is the change
zero
- little to no change when ratio is one
What is in the extracellular buffering system
bicarbonate, plasma proteins, and phosphates
What is in the intracellular buffering system
cytoplasmic proteins, phosphates
how is the bicarbonate buffer system assessed clinically?
arterial blood gas test
What does hydrogen ion concentration depend on?
ratio of HCO3- and Pco2
what is HCO3- produced by
mainly by the RBC all the time, but when needed the kidneys can also produce some bicarbonate
RBC combines CO2 and HCO3- by
carbonic anhydrase intracellularly
normal range of bicarbonate
24-26 mEq/L
How does the kidney regulate bicarbonate?
reabsorption of bicarbonate, production of bicarbonate, and excretion of H+
Nearly all of the ____ in blood gets reabsorbed
bicarbonate
if it is too acidic the kidneys can produce HCO3- but can not buffer so they excrete it with…
ammonia
What does ammonium production from glutamine metabolism result in?
- excretion of more H+
- production of HCO3-
Glutamate deamination yields…
alpha-ketoglutarate and ammonia
the ammonia can attract H+ and
get excreted in the form of ammonium
alpha-ketoglutarate can be further metabolized to yield…
CO2
krebs cycle
someone in acidosis will have what showing up in their urine?
increased ammonium
normal PCO2 levels
32-48 mmHg
Examples of fixed acids
lactic acid and ketone bodies
nonvolatile acids or metabolic acids are referred to as ____ and must be removed by the kidneys (not respiration)
fixed acids
if you have a small fasting period like when you sleep you will have ketones in urine in the morning , but large amounts of ketones leads to …
an acidic situation
a build up of fixed acids can be temporarily compensated by…
rapid removal of cO2
increased Pco2 caused by decreased ventilation
compensation: cellular and renal
respiratory acidosis
decrease in bicarbonate caused by either increased fixed acids or loss of bicarbonate
- compensation: cellular, renal, respiratory
metabolic acidosis
decreased Pco2 caused by increased ventilation
compensation: cellular and renal
respiratory alkalosis
decrease in fixed acids, increase in bicarbonate
compensation: cellular, renal, respiratory
metabolic alkalosis
asthma, COPD, morbid obesity, airway obstruction, over-sedation, COVID-19
causes of respiratory acidosis
increased PCO2, normal or increased HCO3-, increased K+, increased Na+, decreased Cl-
effects of respiratory acidosis
immediate cellular compensation for respiratory acidosis
anti-port exchange of H+/K+ (very limited because K+ is already most concentrated inside the cell)
prolonged compensation for respiratory acidosis
renal:
- production of bicarbonate with ammonium excretion
- anti-port exchange H+/Na+
- increased excretion of Cl- (chloride shift to get bicarbonate)
ketoacidosis, lactic acidosis, toxin intake renal failure, diarrhea/GI disorder
causes of metabolic acidosis
decreased Pco2, decreased HCO3-, inc/dec K+, inc Na+, dec Cl-
effects of metabolic acidosis
immediate metabolic acidosis compensation
cellular: anti-port exchange H+/K+
respiratory: Kussmaul respirations
prolonged metabolic acidosis compensation
renal: -increased excretion of fixed acid - production of bicarb with ammonium excretion - anti-port exchange H+/Na+ - increased excretion of Cl- bone: - increased release of alkaline compounds Ca2+ in urine
Anion Gap equation
AG = [Na+] - ([Cl-] + [HCO3-])
Normal AG
9-16 mEq/L
what is anion gap used for?
metabolic acidosis determination
ketoacidosis, lactic acidosis, toxin intake, salicylate poisoning , advanced renal failure
metabolic acidosis with high AG
diarrhea, other GI loss of bicarbonate, mild to moderate renal disease, dilutional
metabolic acidosis with normal AG
immediate respiratory alkalosis compensation
cellular: antiport exchange H+/K+
prolonged respiratory alkalosis compensation
renal:
- decreased production of ammonium
- decreased excretion of acids
- increased excretion of HCO3-
hyperventilation
- pain, anxiety, sepsis, toxins
causes of respiratory alkalosis
decreased pCO2, decreased HCO3-, slight K+ decrease
effects of respiratory alkalosis
vomiting, diuretics, laxative abuse, renal filtration failure, mineralcorticoids
causes of metabolic alkalosis
decreased H+, inc CO2, inc HCO3-, dec K+, inc Na+, inc Cl-
effects of metabolic alkalosis
metabolic alkalosis compensation: cellular
anti-port exchange H+/K+
metabolic alkalosis compensation: respiratory
decrease in rate and depth
metabolic alkalosis compensation: renal
increased excretion of HCO3-
decreased excretion of acids
