Acid-Base Balance Flashcards
acid-base balance is one of the most important of the body’s ____ mechanisms
homeostatic
acid-base balance refers to regulation of ___ ion concentration in the body
hydrogen
precise regulation of pH at the ___ level is necessary for survival
cellular
slight pH changes have dramatic effects on ____ metabolism
cellular
acid base balance is achieved by utilization of ___ buffers in the extracellular and intracellular fluids
chemical
acid base balance is achieved by ___ mechanisms that excrete ___
respiratory
CO2
acid base balance is achieved by ____ mechanisms that reabsorb ___ and secrete ___ ions
renal
bicarbonate
hydrogen
normal range of arterial pH is ___-___
7.37 - 7.42
acid production in the body (2)
CO2
fixed acid
CO2 is the end product of ___ metabolism; ____ acid
aerobic
volatile
CO2 is a volatile acid because it is the end product of the catabolism of ____ ___
carbonic acid
carbonic acid breaks into ___ and __
CO2 and water
fixed acid is a ___ acid
non-volatile
4 examples of fixed acids
phosphate
phosphoric acid
sulfuric acid
lactate acid
___ are substances that prevent marked change in pH of solution when an acid or base is added to it
buffers
buffers consist of ___ acid and basic ___ of that acid
weak
salt
buffer pairs present in body fluids - 4 acids and 2 salts
- carbonic acid
- proteins
- hemoglobin
- acid phosphate
- sodium
- potassium
nonvolatile acids buffered mainly by ____ ___
sodium bicarbonate
volatile acids buffered mainly by ___ ___ of ___ and ___
potassium salts
hemoglobin
oxyhemoglobin
the chloride shift makes it possible for carbonic acid to be buffered in ___ and then carried as ___ in the plasma
RBC
bicarbonate
bases are buffered mainly by ___ ___
carbonic acid
___-___ equation is a mathematical formula that explains the relationship between hydrogen ion concentration of body fluids and the ratio of base bicarbonate to carbonic acid
Henderson-Hasselbalch
strong acid/base dissociates to a __ acid/base to prevent marked change pH
- ex HCl + NaHCO3 –> HHCO3 + NaCl
- ex NaOH + HHCO3 –> NaHCO3 + HOH
weak
mechanism of Hydrogen ion regulation
- body fluid chemical buffers (4)
bicarbonate
proteins
ammonia
phosphate
mechanism of Hydrogen ion regulation
- lungs
- increase H+ concentration –> ___ ventilation –> increase CO2 ____
increase
loss
mechanism of Hydrogen ion regulation
- kidneys
- secretes ___
- reabsorbs ____
- generates new ___
H+
bicarbonate
bicarbonate
hydrogen regulation by body fluid chemical buffers occurs ___ but ___
rapidly
temporary
hydrogen regulation by the lungs is ___ and eliminates ___
rapid
CO2
hydrogen regulation by the kidney is ___, ___ and eliminates ___ ___
slow
powerful
non-volatile acids
___ is the most important extracellular fluid buffer
bicarbonate
___ and ___ are the important renal tubular buffers
phosphate
ammonia
___ are important intracellular buffers
proteins
__-__% of buffering is int he cells
60-70
effectiveness of buffer system depends on
- ___ of reactants
- ___ of system and ___ of body fluids
concentration
pK; pH
increase [H+] –> ___ alveolar ventilation –> ___ pCO2 –> ____ [H+]
increase
decrease
decrease
urinary mechanism
- reabsorption of ___
- excretion of fixed H+ produced from __ and __ catabolism
HCO3-
protein; phospholipid
bicarbonate in the lumen is broken down and brought into the cell as its end products
- ___ is exchanged with Na+ into the lumen
- bicarbonate is broken down and ___ and ___ diffuses into the cell
H+
CO2
H20
filtered HCO3- is reabsorbed into the blood by:
- ___ with Na+
- ___ with Cl-
symporter
antiporter
bicarbonate is broken down to CO2 and H20 by ___ ___
carbonic anhydrase
excess HCO3- ____ the reabsorptive capacity
exceeds
ECF volume expansion ___ HCO3- reabsorption
inhibits
ECF volume contraction ___ HCO3- reabsorption
stimulates
ECF volume uses the ___ ___ mechanism
angiotensin II
increase in pCO2 –> ___ in HCO3- reabsorption
increase
increase glutamine metabolism –> NH3 + H+ –> NH4 –> excreted to the lumen from the ___ cell –> HCO3- is __
intercalated
reabsorbed
H+ is excreted as NH4
acidosis ___ glutamine metabolism
increase
hyperkalemia ___ NH3 synthesis, causing type 4 renal tubular acidosis
inhibits
hypokalemia ___ NH3 synthesis
stimulates
acidosis ___ ammonia synthesis
stimulates
tritratable acid (H2PO4) = HPO4- + H+ from \_\_\_ acid catabolism
carbonic
metabolisc acid base disorders
- primary disorders involving ___
HCO3-
respiratory acid base disorders
- primary disorders involving ___
CO2
___ ____ ___: a measurement useful in diagnosis of acid-base disorders; based on electronegativity
plasma anion gap
normal range of plasma anion gap
8-16mEq/L
main cation = ___
Na+
main anion is ___
Cl-
anion gap is hard to ___
measure
plasma anion gap is useful primarily in the differential diagnosis of ___ diagnosis
metabolic
if HCO3- is replaced by unmeasured anions, the calculated anion gap is ___
increased
if HCO3- is replaced by Cl-, the calculated anion gap is ___
normal
plasma anion cap = ___ - ___ - ____
[Na+] - [HCO3-] - [Cl-]
in body fluids
- total cations ___ total anions
equals
metabolic acidosis with increased anion gap due to 6 things
diabetic ketoacidosis lactic acidosis salicylate poisoning methanol poisoning ethylene glycol poisoning chronic renal failure
metabolic acidosis with increased anion gapdue to the accumulation of ____ and ___ acids
non-volatile
organic
metabolic acidosis with normal anion gap due to 2 things
diarrhea
renal tubular acidosis
metabolic acidosis with normal anion gap there is ___ ___ anion accumulation
no organic
increase in HCO3 due to acidosis leads to
- slight ___ of tritratable acid
- ___ NH4 excretion
- ___ HCO3 excretion
increase
increase
decrease
loss of HCO3 due to alkalosis leads to a
- ___ of tritratable acid
- ___ NH4 excretion
- ___ HCO3 excretion
decrease
decrease
increase
HCO3 excretion can ___ markedly in ___
alkalosis
acidosis :
- pH ___ 7.4
- metabolic: ___ HCO3-
- respiratory: ___ pCO2
<
decrease
increase
alkalosis:
- pH ___ 7.4
- metabolic: ___ HCO3-
- respiratory: ___ pCO2
> increase
decrease
acidosis:
- ___ H+ excretion
- ___ HCO3- reabsorption
- production of new ____
increased
increased
HCO3-
alkalosis:
- ___ H+ excretion
- ___ HCO3- reabsorption
- loss of ___ in urine
decreased
decreased
HCO3-
respiratory acidosis
- ___ pH
- ___ pCO2
- ___ HCO3-
decrease
increase
increase
respiratory acidosis
- Increased pCO2 –> ___ H+ secretion –> ___ HCO3- reabsorption –> ___ tubular H+ –> ___ H+ buffers and __ new HCO3 –> ___ pH
increase complete excess increase increase increase
metabolic acidosis
- ___ pH
- ___ pCO2
- ___ HCO3-
decrease
decrease
decrease
metabolic acidosis
- decreased HCO3- –> ___ H+ filtration –> ___ HCO3- reabsorption –> ___ tubular H+ –> ___ H+ buffers and __ new HCO3 –> ___ pH
decreased complete excess increase increase increase
respiratory alkalosis
- ___ pH
- ___ pCO2
- ___ HCO3-
increase
decrease
decrease
respiratory alkalosis
- decreased pCO2 –> ___ H+ secretion –> ___ HCO3- reabsorption –> ___ tubular HCO3- –> ___ HCO3- excretion and __ H+ excretion –> ___ pH
decrease decrease excess increase decrease decrease
metabolic alkalosis
- ___ pH
- ___ pCO2
- ___ HCO3-
increase
increase
increase
metabolic alkalosis
- increased HCO3- –> ___ HCO3- filtration –> ___ tubular HCO3- –> ___ HCO3- reabsorption –> __ HCO3- excretion and __ H+ excretion –> ___ pH
increase excess decrease increase decrease decrease
compensation for metabolic acidosis
- ___ ventilation
- ___ renal HCO3 production
increase
increase
compensation for respiratory acidosis
- ___ ventilation
- ___ renal HCO3 production
NO
increase
compensation for metabolic alkalosis
- ___ ventilation
- ___ renal HCO3 production
decrease
increase
compensation for respiratory alkalosis
- ___ ventilation
- ___ renal HCO3 production
NO
increase
primary distrubance for metabolic acidosis
decrease HCO3-
compensation for metabolic acidosis
decrease pCO2 by increase ventilation
primary disturbance for metabolic alkalosis
increase HCO3-
compensation for metabolic alkalosis
increase pCO2 by decrease ventilation
primary disturbance for respiratory acidosis
increase pCO2
compensation for respiratory acidosis
increase HCO3-
primary disturbance for respiratory alkalosis
decrease pCO2
compensation for respiratory alkalosis
decrease HCO3-
respiratory acidosis caused by 4 things
brain damage
pneumonia
emphysema
other lung disorders
metabolic acidosis caused by 4 things
increased base intake
vomiting gastric acid
mineralocorticoid excess
overuse of diuretics
increase aldosterone –> ___ tubular K+ secretion –> K+ ___ –> ___ H+ secretion –> ___ HCO3 reabsorption and __ new HCO3 production –> ___ ___
increase depletion increase increase increase metabolic alkalosis
respiratory alkalosis due to 2 things
high altitude
psychic
