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302 Cards in this Set
- Front
- Back
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1. In most conditions of acid or base loads,
nearly all of the bicarbonate is reabsorbed in which tubular segment? |
proximal tubules
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2. Secretion of bicarbonate occurs in which
tubular segment? |
collecting tubules
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3. secretion of K+ occurs in which tubular
segment? |
collecting tubules
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4. When the dietary load of potassium is high,
A. potassium secretion occurs along the length of the renal tubule B. reabsorption occurs in the proximal tubule, but secretion occurs in the collecting tubule C. reabsorption rate of potassium increases in the proximal tubule D. the filtered load of potassium decreases E. rate of the basolateral Na+/K+ ATPase decreases |
B. reabsorption occurs in the proximal tubule, but secretion occurs in the collecting tubule
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The primary change in renal handling of potassium with diet occurs at the collecting tubules, which either to?
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reabsorb potassium (alpha intercalated cells, collecting tubules)
or secrete potassium (principal cells, collecting tubules). |
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The primary change in renal handling of potassium with diet occurs at the collecting tubules, which could reabsorb potassium from what cells and where?
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alpha intercalated cells, collecting tubules
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The primary change in renal handling of potassium with diet occurs at the collecting tubules, which could secrete potassium from what cells and where?
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principal cells, collecting tubules
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The filtered load would ________ with an increased
plasma [K+]. |
Increase
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increasing the plasma concentration of any filtered solute will?
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Increase the filtered load
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Increasing [K+] of the dietary load will increase the rate of?
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the Na+/K+ ATPase,
which is an important buffering response to the increase K+ load. |
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Increasing [K+] of the dietary load will increase the rate of the Na+/K+ ATPase, which is an important buffering response for
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the increase K+ load.
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5. The hormone that is secreted directly in response to plasma[K+] is
A. renin B. angiotensin II C. aldosterone D. ANP E. vasopressin |
C. aldosterone.
The key to this question is “directly in response to”. |
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The cells of the adrenal cortex secrete more _______ when the plasma[K+] increase
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.Aldosterone
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The cells of the adrenal cortex secrete more aldosterone when?
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the plasma[K+] increase.
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The cells of the ________ secrete more aldosterone when the plasma[K+] increase.
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adrenal cortex
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6. Conditions that increase the flow rate through the renal tubules (such as osmotic diuresis) can
produce hypokalemia because A. Na+ reabsorption in the proximal tubules is increased B. the rate of the apical Na+/K+ ATPase increases with increased flow rate C. increased flow in tubules increases the gradient for K+ transport D. K+ reabsorption increased with increased flow E. all of the above |
C. increased flow in tubules increases the gradient for K+ transport
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The increased flow such as osmotic diuresis helps maintain a favorable gradient for K+ secretion by?
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continuously washing away the secreted K+.
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The Na+/K+ ATPase is always on the _____ membrane.
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Basal
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The rate of this pump will increase with extracellular (plasma) K+.
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Na+/K+ ATPase
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Increased K+ reabsorption would lead to an increased in?
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plasma[K+]
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7. The K+ secreting principal cells
A. are also a primary site of K+ reabsorption under conditions of low K+ B. do not have a basolateral Na+/K+ ATPase C. typically have a low intracellular conc. of K+ D. secrete K+ primarily via paracellular transport E. secrete K+ via an apical, secondary active transporter |
E. secrete K+ via an apical, secondary active transporter
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All of the tubular cells have a basolateral?
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NA+/K+ ATPase.
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This active transport sets up the high intracellular/low extracellular K+ gradient.
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NA+/K+ ATPase.
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Secretion simply requires linking K+ gradient to?
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an apical transporter
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The reabsorption of K+ in the collecting tubule occurs via what different cell type?
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the alpha intercalated cell
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8. A plasma protein exists in an acid (HX) or base (X-) form, depending on the pH of plasma and the pK of the protein. At a plasma pH of 7.35, the ratio of base to acid is 100:1. The pK of this
protein is A.-9.35 B.2.0 C.7.35 D.5.35 E. 9.35 |
D.5.35
pH= pK + log (base or unprotonated form)/ acid (protonated form) pH- log (base or unprotonated form)/ acid (protonated form) = pK since the ratio of unprotonated to protonated form is 100, and the log of 100=2 pK= 7.35 -2 = 5.35 |
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9. Normally, the concentration of [Na+] is approximately _______ greater than that of [H+]
A. 103 B. 104 C. 105 D. 10 E. 106 |
E. 106
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10. The pK of NH4+ is 9.0. If the pH of the tubular fluid is 6.0, then the ratio of NH3 to NH4+ in the tubular fluid must be
A. 1:3 B. 3:1 C. 3:2 D. 1:1000 E. 1000:1 |
D. 1:1000
Use the Henderson-Hasselbalch equation for this reaction: pH= pK + log [NH3]/[NH4+] pH = 6.0 pK= 9.0 the log of the ratio must be -3, which means that the concentration of NH4+ must be 1000 greater than the concentration of NH3. |
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The pH is determined by the ratio of?
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the base to the acid.
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11. An arterial blood plasma sample has a pH of 7.5, and a pCO2 of 20mmHg. The pK is 6.1. In
order to return the plasma pH to normal, the plasma [HCO3-} would have to be: (do this without a calculator!) A. 12 mmol/L B. 48 mmol/L C. 24 mmol/L D. 60 mmol/L E. 2.4 mmol/L |
A. 12 mmol/L
As in problem 10, this requires that you apply the Henderson=Hasselbalch equation, and understand that the pH is determined by the ratio of the base to the acid. pH= pK + log [HCO3-]/[CO2] The pCO2 is half the normal value. In order to restore the pH, we will need to make the HCO3- concentration half its normal value: 12mmol/ L If you did use a calculator, you should have come up with the same answer, only you would need to correct pCO2 to CO2 content (Henry’s law) [CO2]= 0.03 * pCO2, = .6mmol/L in this case If normal pH=7.4, and pK=6.1 Then 7.4= 6.1 + log (hco3-)/ .6 Ln 1.3 = log (HCO3-)/.6 Ln (1.3) = 20 [HCO3-]= 20 * .6 = 12mmol/L It is much easier if you understand the importance of the ratio of base to acid |
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12. An example of an event that would impart a base load on the body is
A. eating a diet high in meat protein B. increasing the secretion of bicarbonate by the pancreas C. vomiting D. holding your breath |
C. vomiting
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There are two ways to get a base load to the body?
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adding bicarbonate to the plasma,
or removing CO2. |
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Secreting bicarbonate is equivalent to?
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adding acid to the plasma
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Holding your breath is hypoventilation, which leads to?
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an increased pCO2, and acidosis
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13. The buffering system with the fastest complete response to an acid or base disturbance is
A. the respiratory ventilation rate B. buffering within the extracellular fluid compartment C. exchange of extracellular H+ for intracellular K+ D. change in the secretion of HCO3 E. change in the rate of renal formation of ammonium |
B. buffering within the extracellular fluid compartment
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The extracellular buffers are extremely?
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fast acting.
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The intracellular buffers are slower buffers because?
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it takes more time for the H+ to be transported into the cells.
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14. A molecule of HCO3- that is lost from the body via the GI tract
A. can combine with a H+ in the body to form CO2 and H2O B. is equivalent to the addition of one fixed H+ to the body C. is compensated for by renal secretion of one HCO3- molecule D. all of the above. |
B. is equivalent to the addition of one fixed H+ to the body
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15. Carbonic anhydrase is found
A. in solution in the plasma B. in solution in the tubular fluid C. bound to apical membranes in proximal tubule cells D. all of the above |
C. bound to apical membranes in proximal tubule cells
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Carbonic anhydrase is found?
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bound to apical membrane of tubular cells and is also located within the cell.
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carbonic anhydrase is bound to apical membrane of tubular cells and is also located within the cell, but within the cell it is not found just as?
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a solute within the plasma, or within the tubular
fluids |
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Carbonic anhydrase is bound to apical membrane of tubular cells, and in that location, can do what within the lumen?
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catalyze the formation of CO2 and H2O within the lumen.
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16. Which of the following statements about bicarbonate is INCORRECT:
A. bicarbonate excretion increases during alkalosis B. bicarbonate in the proximal tubule is reabsorbed primarily as H2CO3 C. bicarbonate reabsorption is dependent on carbonic anhydrase D. most of the bicarbonate is reabsorbed by the proximal tubules E. bicarbonate reabsorption in the proximal tubule depends on a Na+/H+ apical antiport. |
B. bicarbonate in the proximal tubule is reabsorbed primarily as H2CO3
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The molecules that enter the cell apically are?
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CO2 and H20;
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the molecule that exits the cell basolaterally is?
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HCO3-.
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17. During the response to an acid load
A. glutamine is metabolized to bicarbonate in the lumen of the collecting duct molecule of H+ C. reabsorption of filtered bicarbonate is usually sufficient to compensate for the load D. carbonic anhydrase catalyzes the formation of ammonium from glutamine E. all of the above. |
B. addition of one molecule of bicarbonate to plasma is equivalent to the secretion of one
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18. In compensating for a daily acid load, the kidneys
A. excrete H+ bound to buffers B. excrete excess H+ instead of reabsorbing HCO3- C. excrete most of the acid as free [H+] D. excrete H+ in exchange for glutamine primarily in the distal tubules E. excrete H+ bound to glutamine |
A. excrete H+ bound to buffers
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With an acid load, any of the filtered HCO3- will be?
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reabsorbed
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With an acid load , any additional H+ will?
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bind to various buffers in the tubular fluid. And
very little of it will remain as dissociated, free H+ |
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The role of glutamine during an acid load is that it can be converted to?
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intracellularly, to ammonium and bicarbonate.
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The role of glutamine during an acid load is that it can be converted to intracellularly, to ammonium and bicarbonate. Then what happens?
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The bicarbonate is transported into the plasma, and the ammonium transported into the tubular
fluid. |
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What is excretion?
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what actually shows up in the urine
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What is secretion?
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the transport of ions across the membrane.
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19. The beta intercalated cell of the collecting tubule
A. is the target for vasopressin in regulating water reabsorption B. is the primary site of K+ secretion C. is the primary site of K+ reabsorption in the collecting tubules D. is the primary site of HCO3- secretion in the collecting tubules E. is the primary site of HCO3- reabsorption in the collecting tubules |
D. is the primary site of HCO3- secretion in the collecting tubules
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20. Under conditions of an acid load, glutamine:
A. is the primary non-carbonic acid buffer in the plasma B. is converted to NH3 and HCO3- within the cell C. combines with HCO3- within the tubular fluid D. dissociates into H+ and HCO3- by a reaction catalyzed by carbonic anhydrase E. is synthesized by the liver at an increased rate |
E. is synthesized by the liver at an increased rate
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What is the reason that glutamine can play an increasing role with an increased H+ load
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is synthesized by the liver at an increased rate and it can eventually contribute a bicarbonate ion to the plasma.
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With an increased H+ load, Glutamine role is split into?
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NH4+ (not NH3) and HCO3-.(not catalyzed by carbonic anhydrase)
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Glutamine is important in dealing with an acid load
Because? |
it can eventually contribute a bicarbonate ion to the plasma.
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21. An individual filters
4500mmol HCO3- / day, and excretes 30mmol/day of titratable acid, 50mmol/day of NH4+, and 10mmol/day of HCO3-. How much HCO3- is added per day to the plasma? A. 90mmol B. 70 mmol C. 50mmol D. 30mmol E. 4600 mmol |
B. 70 mmol
(30mmol/day of titratable acid + 50mmol/day of NH4+) - 10mmol/day of HCO3-. = 70 mmol the total HCO3- added to the plasma is the same as the total acid excreted total acid excreted = titratable acid + ammonium – excreted bicarbonate |
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excreting a bicarbonate ion is the same as?
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adding a H+ to the plasma
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The bicarbonate added to the plasma is ……….not the……..
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the net, new bicarbonate,
reabsorption of the filtered bicarbonate. |
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22. An individual has a pulmonary disease, and now hyperventilates. Which of the following will
occur as a result? A. the arterial pCO2 will be higher than normal B. plasma [HCO3-] will be higher than normal C. renal tubules will compensate by secreting more [HCO3-] than normal D. renal tubules will compensate by secreting more NH4+ than normal E. plasma buffers will maintain pH at the normal level |
C. renal tubules will compensate by secreting more [HCO3-] than normal
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An individual has a pulmonary disease, and now hyperventilates,hyperventilation will produce and a ______ pCO2
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respiratory alkalosis,
lower than normal |
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An individual has a pulmonary disease, and now hyperventilates, the low pCO2 from respiratory alkalosis, will result of mass action on the plasma buffers, the plasma[HCO3-] will?
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decrease although slightly
The renal tubules compensate by further lowering the HCO3- by secreting more in the tubules. This dercease in HCO3- will balance the decreased pCO2, and help restore the pH closer to normal . |
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There are no simple acid-base disturbances that would produce?
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a decrease in pCO2 and an increase in plasma [HCO3-].
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The plasma buffers reduce the pH change, but cannot?
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eliminate the pH change
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23. An individual has respiratory acidosis. With renal compensation, you would expect to find
what difference, compared to the acute (non-compensated) situation? A. plasma [HCO3-] will be much greater than normal B. a pH will be greater than normal C. the ventilatory rate will return to normal D. pCO2 will be slightly lower than normal E. plasma [HCO3-} will be slightly lower than normal |
A. plasma [HCO3-] will be much greater than normal
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23. A. Respiratory acidosis is?
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an increased pCO2 caused by hypoventilation.
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An individual has respiratory acidosis. With renal compensation, The ventilatory rate would only change if?
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the underlying condition were changed and is not directly tied to renal compensation.
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During respiratory acidosis, there is an increase in pCO2. In the acute phase, there will be a slight increase in?
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HCO3-, but the renal
system will increase this further. |
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An individual has respiratory acidosis. With renal compensation, How could this be balanced?
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The increased HCO3- will help balance the increased CO2, and return the pH to normal
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24. Which of the following would be the plasma values found in an individual with respiratory alkalosis with renal compensation?
pH PaCO2 (mmHg) [HCO3−] (mM) A. 7.18 60 25 B. 7.33 60 32 C. 7.53 50 30 D. 7.49 30 18 E. 7.62 20 26 |
D. 7.49 30 18
pH 7.49 PaCO2 (mmHg) 30 [HCO3−] (mM) 18 Begin with the pH. Alkalosis means that the pH is greater than normal, eliminating A and B. Respiratory alkalosis is produced by a decreased pCO2, produced by hyperventilation. The pCO2 must be less than normal, eliminating C. you should expect that any compensation to a change in pCO2 should be a change in bicarbonate, and that change should occur in the same direction, in this case a decrease. |
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pH 7.53
PaCO2 – 50 (mmHg) [HCO3−] – 30 (mM) Note that the values are consistent with? |
a metabolic alkalosis.
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Alkalosis means that the pH is?
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greater than normal,
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Respiratory alkalosis is produced by?
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a decreased pCO2, produced by hyperventilation.
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you should expect that any compensation to a change in pCO2 should be a change in _____________ , and that change should occur in ….
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bicarbonate
the same direction |
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25. What is the minimum amount of information you need in order to distinguish a metabolic from a respiratory acid/base disturbance?
A. pH B. pH and pCO2 C. pH, pCO2 and plasma[HCO3-] D. pH, pCO2, plasma[CHO3-] and net urine acid excretion rate E. pH, pCO2, plasma[CHO3-], net urine acid excretion rate and urine pH |
B. pH and pCO2
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By itself, the pH will tell you ..... but .....
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if it is an acidosis or alkalosis, not the cause.
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Knowing the CO2 will help you distinguish ________ disturbance
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the cause whether metabolic or respiratory
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If it were respiratory acidosis, then the pCO2 would be _____________ – as the cause of the disturbance.
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higher than normal
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If it were metabolic acidosis, then the respiratory system would compensate for the
decrease HCO3- by? |
decreasing the pCO2 (hyperventilating).
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26. An elderly man comes to the clinic after 3 days of recurrent vomiting, and has the following
arterial blood values: pH=7.5 pCO2= 55mmHg [HCO3-] = 40mmol/L Which of the following is your tentative diagnosis? A. chronic respiratory alkalosis B. Metabolic alkalosis with respiratory compensation C. Acute respiratory acidosis with no renal compensation D. Metabolic acidosis with respiratory compensation E. Acute respiratory alkalosis with no renal compensation |
B. Metabolic alkalosis with respiratory compensation
Begin with the pH. A pH of 7.50 is higher than normal, so this is some type of alkalosis. The pCO2 is higher than normal, so the respiratory rate is not the cause of the alkalosis, it is a compensation for the alkalosis. Note that the bicarbonate level is also above normal. The high bicarbonate is the cause of this disturbance. The renal system will help restore the pH be secreting more bicarbonate. As the bicarbonate falls, the respiratory system will follow. |
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27. For an individual with metabolic acidosis,
A. plasma buffers will raise the pH slightly above normal B. ventilatory rate will increase C. renal compensation will occur prior to the ventilatory rate D. renal compensation will secrete more HCO3- in the urine E ventilatory rate will stay the same as renal compensation occurs. |
B. ventilatory rate will increase
By mass action, the plasma HCO3- will drop as the acid increased due to this metabolic problem. The buffers mitigate the pH change, but there will still be a decrease in pH, not an increase. The respiratory system will compensate first (C), and will do so by hyperventilating, thereby decreasing pCO2 The kidney will secrete less bicarbonate, not more, and will further excrete H+, and make new plasma bicarbonate Ventilatory rate changes with the pH. As the renal compensation brings the pH closer to normal, the ventilatory rate will adjust to the new pH |
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What are normal:
Arterial plasma - pH Plasma [HCO3-] - mmol/L pCO2 - mmHg |
Arterial plasma pH – 7.35 – 7.43
Plasma [HCO3-] - 24 mmol/L pCO2 – 40 mmHg |
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pH = ?
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-log[H+]
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Most enzymes and proteins normally function over a narrow range of pH, therefore regulating pH is?
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critical.
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Most enzymes and proteins normally function over a narrow range of pH, therefore regulating pH is critical. Example
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Production of ATP
Metabolism of free fatty acids Synthesis of cell membranes Acetylcholine binding to Ach receptor |
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What pH is incompatible with life?
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Less than 6.8 and Greater than 7.8
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decreasing pH is ___ [H+]
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increasing
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increasing pH is ___ [H+]
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decreasing
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pH depends on?
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temperature
PCO2 Plasma Plasma[protein] [strong base cations]- [strong acid anions] strong ion difference |
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pH depends temperature how?
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increased temp~~> Increased [H+]
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pH depends PCO2 how?
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increased PCO2 ~~> increased [H+]
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pH depends on strong ion difference how?
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increased SID ~~> Decreased [H+]
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Normal [H+] = 40nmol
TBW = 42L total body H+ = ? |
TBW * Normal [H+]
42L * 40nmol/L = 1.6 μmol |
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typical dietary process expels ____ CO2 in exhaling
& ____ non carbonic (non volatile) acid |
13mol
40-80 mmol |
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Buffer- + H+ <~~~> HBuffer
Which is the weak base? Which is the weak acid? |
W.B ~~ Buffer
W.A ~~ H+ |
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pH can vary btwn 4.4 to 7.4 but never gets to 4.4 because of?
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Buffers
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Buffer is?
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“base” form,
because it results in a decreased [H+] of that solution |
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H buffer is?
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“acid” form,
because results in a increased [H+] of that solution |
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Mass Action:
** Buffer- + H+ <~~> HBuffer ** rate of the reaction is proportional to? |
the concentration of the reactants (esp. H+)
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Mass Action:
** Buffer- + H+ <~~> HBuffer ** an increase in H+ drives reaction to the? |
Right
** Buffer- + H+ <~~~ HBuffer ** |
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Mass Action:
** Buffer- + H+ <~~> HBuffer ** an decrease in H+ drives reaction to the? |
Left
** Buffer- + H+ ~~~> HBuffer ** |
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Mass Action:
** Buffer- + H+ ~~> HBuffer ** in H+, what drives reaction to the Right? |
Increase in H+
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Mass Action:
** Buffer- + H+ <~~ HBuffer ** in H+, what drives reaction to the Leftt? |
Decrease in H+
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Buffers do what?
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minimize the pH change (change in free concentration of H+) but do not remove acid or base
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Resulting pH w/ buffer = formula
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pK + log [base]/[acid]
(Henderson-Hasselbalch equation) |
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Buffering capacity of the body is huge, but over the long term, buffers have?
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to be restored
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Buffering capacity of the body is huge. Why?
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A lot of buffers (and many pKa are close to their pH)
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Disease processes can tax buffering capacity, placing additional requirement for?
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restoring buffers
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What can tax buffering capacity, placing additional requirement for restoring buffers
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Disease processes
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What are the sources of acids and bases?
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1. Carbonic Acid (Volatile acid)
2. Non-carbonic (non-volatile) acid 3. GI secretions |
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What is this equation?
CO2* + H2O <~>H2CO3<~>H+* + HCO3- * catalyzed by carbonic anhydrase |
Carbonic Acid (Volatile acid)
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What two components are catalyzed by carbonic anhydrase?
CO2 + H2O <~>H2CO3<~>H+ + HCO3- |
CO2 and H+ of the formula:
CO2* + H2O <~>H2CO3<~>H+* + HCO3- * catalyzed by carbonic anhydrase |
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Carbonic Acid (Volatile acid) generates how many moles of CO2 a day and how is it expelled?
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13 moles of CO2
Exhaled |
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Carbonic anhydrase is not found in plasma (ECF), but is found in?
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RBCs and numerous other tissues including:
renal tubular cells, pulmonary tissue, CNS, and as membrane bound forms in muscle and other tissues.) |
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What is the source of Non-carbonic (non-volatile) acid?
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Proteins: oxidative metabolism can result in the addition of acid, or of base, depending on the type of
protein. |
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Oxidative metabolism of Non-carbonic (non-volatile) acid can result in depending on the type of protein?
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the addition of acid, or of base
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Average American diet of high protein (mainly meat) produces a net acid of ____ mM/day
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50-100 mM/day
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What are the special elements of Non-carbonic (non-volatile) acid?
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H2SO4, H2PO4
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Anaerobic metabolism of carbohydrate and fat produces _______ which can be a significant addition of Non-carbonic (non-volatile) acid in some pathological conditions.
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lactate,
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Who produces ketones, which can be a significant addition of Non-carbonic (non-volatile) acid in some pathological conditions.
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diabetics
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Stomach acid secretion is balanced by?
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small intestine base, but vomiting or diarrhea results in an acid or base deficit, respectively.
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Stomach acid secretion is balanced by small intestine base, but what results in an acid or base deficit, respectively.
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vomiting or diarrhea
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Bicarbonate and base equivalents (organic anions) that are normally lost in the stool contribute an?
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equimolar quantity of non-carbonic acid being left behind.
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In GI secretions, every mole of base lost in the stool, one mole of acid is?
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retained by the ECF
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Acids and bases must balance. Transient changes in acids or bases are compensated so that?
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acids and bases return to balance, even if it is at a higher or lower concentration
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What is the response to acid or base load?
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1.Chemical buffers
2. Respiratory compensation 3. Renal compensation |
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What are the three types of buffers in response to acid or base load?
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Plasma bicarbonate/CO2
Protein buffers Phosphate buffers |
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Formula for Plasma bicarbonate/CO2 is
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(H+) + HCO3- <~> H2CO3 <~> CO2 + H2O
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Formula for Plasma bicarbonate/CO2 is:
(H+) + HCO3- <~> H2CO3 <~> CO2 + H2O If you add acid to this equation what happens? |
Increase CO2, decrease HCO3-
Goes right (H+) + HCO3- ~> H2CO3 ~> CO2 + H2O |
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What does Plasma bicarbonate/CO2 do and what is it responsible for?
|
Major buffer
• Responsible for >75% of plasma buffering capacity for protons from non-carbonic acids • does not buffer protons from carbonic acid sources |
|
|
Formula for Plasma bicarbonate/CO2
(H+) + HCO3- <~> H2CO3 <~> CO2 + H2O If you remove H+ to this equation what happens? |
Decrease CO2, Increase HCO3-
Goes Left (H+) + HCO3- <~ H2CO3 <~ CO2 + H2O |
|
|
What is this equation?
CO2* + H2O <~>H2CO3<~>H+* + HCO3- * catalyzed by carbonic anhydrase |
Carbonic Acid (Volatile acid)
|
|
|
What two components are catalyzed by carbonic anhydrase?
CO2 + H2O <~>H2CO3<~>H+ + HCO3- |
CO2 and H+ of the formula:
CO2* + H2O <~>H2CO3<~>H+* + HCO3- * catalyzed by carbonic anhydrase |
|
|
Carbonic Acid (Volatile acid) generates how many moles of CO2 a day and how is it expelled?
|
13 moles of CO2
Exhaled |
|
|
Carbonic anhydrase is not found in plasma (ECF), but is found in?
|
RBCs and numerous other tissues including:
renal tubular cells, pulmonary tissue, CNS, and as membrane bound forms in muscle and other tissues.) |
|
|
What is the source of Non-carbonic (non-volatile) acid?
|
Proteins: oxidative metabolism can result in the addition of acid, or of base, depending on the type of
protein. |
|
|
Oxidative metabolism of Non-carbonic (non-volatile) acid can result in depending on the type of protein?
|
the addition of acid, or of base
|
|
|
Average American diet of high protein (mainly meat) produces a net acid of ____ mM/day
|
50-100 mM/day
|
|
|
What are the special elements of Non-carbonic (non-volatile) acid?
|
H2SO4, H2PO4
|
|
|
Anaerobic metabolism of carbohydrate and fat produces _______ which can be a significant addition of Non-carbonic (non-volatile) acid in some pathological conditions.
|
lactate,
|
|
|
Who produces ketones, which can be a significant addition of Non-carbonic (non-volatile) acid in some pathological conditions.
|
diabetics
|
|
|
Stomach acid secretion is balanced by?
|
small intestine base, but vomiting or diarrhea results in an acid or base deficit, respectively.
|
|
|
Stomach acid secretion is balanced by small intestine base, but what results in an acid or base deficit, respectively.
|
vomiting or diarrhea
|
|
|
Bicarbonate and base equivalents (organic anions) that are normally lost in the stool contribute an?
|
equimolar quantity of non-carbonic acid being left behind.
|
|
|
In GI secretions, every mole of base lost in the stool, one mole of acid is?
|
retained by the ECF
|
|
|
Acids and bases must balance. Transient changes in acids or bases are compensated so that?
|
acids and bases return to balance, even if it is at a higher or lower concentration
|
|
|
What is the response to acid or base load?
|
1.Chemical buffers
2. Respiratory compensation 3. Renal compensation |
|
|
What are the three types of buffers in response to acid or base load?
|
Plasma bicarbonate/CO2
Protein buffers Phosphate buffers |
|
|
Formula for Plasma bicarbonate/CO2 is
|
(H+) + HCO3- <~> H2CO3 <~> CO2 + H2O
|
|
|
Formula for Plasma bicarbonate/CO2
(H+) + HCO3- <~> H2CO3 <~> CO2 + H2O If you add acid to this equation what happens? |
Increase CO2, decrease HCO3-
Goes right (H+) + HCO3- ~> H2CO3 ~> CO2 + H2O |
|
|
Formula for Plasma bicarbonate/CO2
(H+) + HCO3- <~> H2CO3 <~> CO2 + H2O If you remove H+ to this equation what happens? |
Decrease CO2, Increase HCO3-
Goes Left (H+) + HCO3- <~ H2CO3 <~ CO2 + H2O |
|
|
What does Plasma bicarbonate/CO2 do and what is it responsible for?
|
Major buffer
• Responsible for >75% of plasma buffering capacity for protons from non-carbonic acids • does not buffer protons from carbonic acid sources |
|
|
Formula for calculating pH containing dissolved CO2 (Plasma bicarbonate/CO2)
|
pH= pK + log[HCO3-]/(.03*pCO2)
Henry’s Law (.03*pCO2) converts the pCO2 to the molar content of dissolved CO2) |
|
|
What restores the HCO3- in plasma bicarb. / CO2?
|
Renal function
|
|
|
What are composed as Protein buffers?
|
Hemoglobin in red blood cells, albumin in plasma, intracellular proteins
|
|
|
Hemoglobin buffer equation:
|
(H+) + Hb- <~> H*Hb
|
|
|
With Protein buffers, When H+ enters the cells, often it is balanced by?
|
the exit of Na+ or K+
|
|
|
Phosphate buffers are both?
|
organic and inorganic elements
|
|
|
The two equations of Phosphate buffers
|
(H+) + Org*HPO4- <~> Org*H2PO4-
(H+) + HPO4- <~> H2PO4- |
|
|
In Phosphate buffers, buffers protons are from?
|
both carbonic and non-carbonic acid sources
|
|
|
Respiratory compensation is responsible for?
|
Regulating PCO2
(H+) + HCO3- <~> H2CO3 <~> CO2 + H2O |
|
|
How does Respiratory compensation Regulate PCO2?
|
• rapid response, although slower than chemical buffering systems
• bicarbonate _ CO2 in RBCs in the lung capillary |
|
|
Respiratory compensation formula:
|
(H+) + HCO3- <~> H2CO3 <~> CO2 + H2O
|
|
|
Ventilation rate changes in order to increase or decrease CO2 in?
|
Respiratory compensation in Regulating PCO2
|
|
|
In respiratory compensation in Regulating PCO2, What changes in order to increase or decrease CO2?
|
Ventilation rate changes
|
|
|
A decrease in pH will cause ________ and will ___________ ventilation and decreases _____
|
Acidosis
Increase ventilation CO2 |
|
|
A increase in pH will cause ________ and will ___________ ventilation and will increase ________
|
Alkalosis
Decrease ventilation pCO2 |
|
|
Alkalosis is an _______ in H+
|
decrease
|
|
|
Acidosis is an ________ in H+
|
increase
|
|
|
Acidosis will move the following rxn which way?
(H+) + HCO3- <~> H2CO3 <~> CO2 + H2O |
to the left
(H+) + HCO3- <~ H2CO3 <~ CO2 + H2O |
|
|
How does Renal compensation affect acid/base balance?
|
Long term regulation by altering HCO3- concentration – restoring buffering capacity
• excrete bicarbonate in urine (equivalent to increasing H+ to the plasma) • secrete HCO3- into plasma (equivalent to removing a H+ ion from the plasma) |
|
|
How does Renal compensation excrete to restore buffering capacity?
|
• excrete bicarbonate in urine (equivalent to increasing H+ to the plasma)
|
|
|
How does Renal compensation secrete to restore buffering capacity?
|
• secrete HCO3- into plasma (equivalent to removing a H+ ion from the plasma)
|
|
|
Although buffers of renal compensation mitigate the pH changes due to?
|
an acid or base load, acid base balance means that the buffers must be restored, and any excess acid or base must also be excreted.
|
|
|
acid base balance means that the buffers must be?
|
restored, and any excess acid or base must also be excreted
|
|
|
Typical individual: generates about_____ mmol CO2/day which is excreted by?
|
15,000 mmol CO2/day
Exhaled |
|
|
Protein in avg. diet, generates ??? mmol non carbonic H+ /day
|
~ 40-80 mmol non carbonic H+ /day
H+ (from any source) + HCO3- (plasma) <~~> CO2 + H20 |
|
|
The added H+ in renal handling of acid/base does not change pH, but it does?
|
eliminate one bicarbonate as part of the buffering process.
|
|
|
The added ____ in renal handling of acid/base does not change pH, but it does eliminate _______________ as part of the buffering process.
|
H+
one bicarbonate |
|
|
The added H+ in renal handling of acid/base does not change pH, but it does eliminate one bicarbonate as part of the buffering process.Acid/base balance requires?
|
that this bicarbonate be restored.
|
|
|
In regards to renal handling of acid/base, HCO3- is freely filtered at the kidney, so the kidney must do two things:
|
reabsorb the current filtered bicarbonate,
regenerate additional bicarbonate (excrete acid) to balance the load of nonvolatile acids |
|
|
What are the normal values of HCO3- and pH of Plasma?
|
HCO3- = 24 mMol
pH = 7.4 |
|
|
What are the normal values of HCO3- and pH of ICF?
|
HCO3- = 10 mMol
pH = 7.2 |
|
|
What are the normal values of HCO3- and pH of Urine?
|
HCO3- = 0 mMol on typical diet
pH = 5.0 – 7.0 |
|
|
HCO3- is filtered how?
|
freely filtered
|
|
|
What is the magnitude of transport of HCO3
Filtered Load ~~ ? mmol/day Excreted ~~ ? mmol/day Reabsorbed~~ ? mmol/day % filtered load reabsorbed ?% |
Filtered Load ~~4500mmol/day
Excreted ~~2mmol/day Reabsorbed~~4498mmol/day % filtered load reabsorbed ~~ 99.9* * depends on diet, and other conditions- |
|
|
What part of the nephron reabsorbs the most HCO3-?
|
Proximal tubules
|
|
|
Distal regions of the Nephron does what with the HCO3-?
|
reabsorbs more HCO3- or secretes HCO3- as needed for acid/base balance
|
|
|
What part of the nephron reabsorbs more HCO3- or secretes HCO3- as needed for acid/base balance?
|
Distal regions
|
|
|
In the distal regions of the Nephron, Reabsorbing 1HCO3- is equivalent to?
|
Excreting one H+ in urine
|
|
|
In the distal regions of the Nephron, secreting 1 HCO3- is equivalent to
|
Add H+ to plasma
|
|
|
What is the formula for
[HCO3-] excreted? |
[HCO3-] excreted =
[HCO3-] filtered + [HCO3-]secreted – [HCO3-] reabsorbed |
|
|
The most reabsorption of filtered HCO3- happens in the?
|
Proximal tubule
|
|
|
What is filtered and/or secreted in the proximal tubule?
|
HCO3- is filtered; H+ is secreted
|
|
|
What are the steps of filtering HCO3- in the proximal tubule?
|
H+ combines with filtered HCO3- in lumen to form
H20 and CO2 Intracellular HCO3- enters interstitium Carbonic anhydrase is present within the cell, and on the luminal side of the plasma membrane HCO3- is filtered into the lumen and HCO3- is released into the plasma |
|
|
What are the Specific transporters in proximal tubule for H+ secretion?
|
H+ ATPase,
Na+/H+ antiport |
|
|
What are the Specific transporters in proximal tubule for HCO3- reabsorption?
|
HCO3-/Cl- antiport,
HCO3-/Na+ symport |
|
|
What percentage of filtered load is reabsorbed in proximal tubule?
|
75-90%
|
|
|
Where does homeostasis matter the most?
|
Collecting tubule
|
|
|
In the Collecting tubule, Alpha intercalated cells have an ……………………exchange
|
apical H+ ATPase
and a basolateral HCO3-/Cl- exchange |
|
|
In the Collecting tubule, Except during __________, kidneys reabsorb all bicarbonate
|
Alkalosis
|
|
|
What completes reabsorption of all bicarb?
|
Kidneys
|
|
|
What is the result of transport of HCO3 in the collecting tubules?
|
no net increase in plasma bicarbonate
No net increase in H+ in tubules. |
|
|
Formation of new bicarbonate to the plasma formula:
CO2 + H2O <~> H2CO3 <~> H+ (urine) + HCO3- (blood) Where is new bicarbonate added to plasma formula: |
CO2 + H2O <~> H2CO3 <~> **H+ (urine)** + **HCO3- (blood)**
|
|
|
With excess of H+ in plasma, the H+ will?
|
combine w/ non-bicarb. anions, usually (HPO4)2-
|
|
|
With excess of H+ in plasma, the H+ will combine w/ non-bicarb. anions, usually (HPO4)2- to form what equation:
|
(H+) + (HPO4)2- <~~> (H2PO4)-
|
|
|
Normally, H+ excretion associated with phosphate will balance about ____ mM/day of H+.
|
40 mM/day of H+
|
|
|
You can add ______ of HCO3- everyday in plasma
|
40 mM/day
|
|
|
On a typical American diet, additional mechanisms other than ..... are necessary to balance the acid load.
|
Formation of new bicarbonate
|
|
|
Formation of new bicarbonate results in?
|
Excreted H+ in tubular fluid
|
|
|
Formation of new bicarbonate will excrete ____ in urine and ______ in plasma
|
H+ (acid)
HCO3- |
|
|
Formation of new bicarbonate if you still need more is?
|
ammonium secretion and production
|
|
|
Catabolism of amino acids produces two waste products that the kidney must excrete:
|
urea or glutamine
amino acids <~> (aerobic) 2NH4+ + 2HCO3- <~> (liver) urea or glutamine (+ CO2 & H2O) |
|
|
What is Glutamine:
|
A waste product in the Proximal tubule
|
|
|
Glutamine is filtered by Kidney and taken up by tubular cells (particularly proximal tubule) from?
|
both lumen and peritubular capillaries.
|
|
|
Glutamine is filtered by the _______ and taken up by _______ from both lumen and peritubular capillaries.
|
Kidneys
tubular cells (particularly proximal tubule) NH4+ <~~> NH3 + H+ |
|
|
Glutamine is metabolized to?
|
NH4+ and HCO3-
|
|
|
Glutamine increases with ______ pH
|
Decreased
|
|
|
Formation of new bicarbonate with ammonium secretion and production will result in
|
1 H+ in urine (apical) and 1 HCO3- added to plasma (baso)
|
|
|
A titratable acid is aka:
|
Formation of new bicarbonate
|
|
|
Glutamine During Formation of new bicarbonate what is actively secreted and by what exchange?
|
Small amount of NH4+ is actively secreted (NH4+/Na+ exchange)
|
|
|
What is the NH4+ and Secretion of H+ net effect in the Collecting duct:
|
The net effect is the formation of on new bicarbonate in the blood, and the loss of one H+ buffered by NH3
|
|
|
Summary of response to an acid load:
|
1. reabsorbed all filtered HCO3-
2. add new HCO3- & excrete H+ either with titratable acid and NH4+ |
|
|
What is base load?
|
High plasma HCO3-
|
|
|
What is the response to a base load?
|
Excretion of Bicarbonate
|
|
|
Normally, bicarbonate excretion is not part of the renal compensation to daily load, but it can be?
|
important in compensation for metabolic disturbances.
|
|
|
What happens in the Collecting tubule with base load?
|
Excretion
|
|
|
Beta intercalated cells have what type of exchangers?
|
apical bicarbonate/Chloride exchange,
basolateral H+/K+ exchange. |
|
|
What is the net result in the Collecting tubule with base load?
|
The net result is excretion of one bicarbonate (gain of HCO3-)
and An addition of one H+ into the plasma (loss of HCO3-) |
|
|
What are the principle cells of collecting tubule cells?
|
Na+
K+ H2O |
|
|
Na+ & K+ do what in the collecting tubule?
|
Reabsorb NA+ and Secrete K+ by Aldostrone
|
|
|
H2O does what in the collecting tubule?
|
Vasopressin regulation of water permeability
|
|
|
What are the Alpha intercalated cells of collecting tubule cells?
|
K+
H+ |
|
|
What does K+ of collecting tubule cells do?
|
K+ is reabsorbed
|
|
|
What does H+ of collecting tubule cells do?
|
H+ additional H+ secretion and HCO3- reabsorbed
|
|
|
What are the Beta intercalated cells of collecting tubule cells?
|
HCO3-
|
|
|
What does the HCO3 of collecting tubule cells do?
|
HCO3- secretion of HCO3-
|
|
|
Acid/base balance equation
acid load = acid loss |
Non volatile acid + volatile (CO2) = excreted acid + exhaled CO2
|
|
|
What takes care of exhaled CO2 in this Acid/base balance equation
|
Resp. system takes care of CO2
|
|
|
Net acid excretion (G/E/L) net non volatile acid load
|
should equal
|
|
|
What is the “signal” for kidney regulation of acid base?
(H+) + HCO3- <~> H2CO3 <~>CO2 + H2O |
CO2 may have specific effects
|
|
|
Net acid excretion in the urine (G/S/L) amount of HCO3- added to plasma
|
same as
|
|
|
Net acid Excretion formula:
|
(Titratable Acid + NH4) – (Any excreted HCO3-) =
New HCO3- has been added to plasma [H+] is not included in this calculation: pH of urine cannot go lower than about 4.5 |
|
|
Net acid Excretion formula:
(Titr. Acid + NH4)– (Any excreted HCO3-) What is not included in this calculation: |
[H+]
|
|
|
Find the net acid excretion for any individual with the following urine composition:
Titratable acid = 40mmol/day NH4+ = 160mmole/day HCO3- = 4mmol/day pH (urine)= 4.6 |
(40 mmol/day + 160mmole/day) – 4 mMol/day
= 196 mMol/day (this net acid excretion is higher than usual) |
|
|
Renal compensation main function is?
|
changing the plasma bicarbonate
|
|
|
Net Acid excreted:
alkalosis – high HCO3- in plasma What are the avg. values for: titratable acid (mM/day) Plus NH4+ excreted (mM/day) minus HCO3- excreted total (mM/day) Urine pH |
titratable acid ~ 0 mM/day
Plus NH4+ excreted ~ 0 mM/day Minus HCO3- excreted 80 mM/day total ~ -80 mM/day (lost from body) Urine pH ~ 8.0 |
|
|
Net Acid excreted:
normal ~ avg. HCO3- in plasma What are the avg. values for: titratable acid (mM/day) Plus NH4+ excreted (mM/day) minus HCO3- excreted total (mM/day) Urine pH |
titratable acid ~ 20 mM/day
Plus NH4+ excreted ~ 40 mM/day Minus HCO3- excreted 1 mM/day total ~ 59 mM/day (add to body) Urine pH ~ 6.0 |
|
|
Net Acid excreted:
acidosis- Low HCO3- in plasma What are the avg. values for: titratable acid (mM/day) Plus NH4+ excreted (mM/day) minus HCO3- excreted total (mM/day) Urine pH |
titratable acid ~ 40 mM/day
Plus NH4+ excreted ~ 160 mM/day Minus HCO3- excreted 0 mM/day total ~ 200 mM/day (added to body) Urine pH ~ 4.6 |
|
|
We can excrete mMol/day of Acid
|
500 mMol/day
|
|
|
In acidosis conditions, a glutamine increase will do what to pH?
|
Decrease pH
|
|
|
Acidosis is elevated …. in plasma and pH is G/S/L normal
|
elevated H+ concentration
pH < normal |
|
|
Alkalosis is elevated …. in plasma and pH is G/S/L normal
|
elevated HCO3- concentration
pH > normal |
|
|
pH can tell you ……. But it doesn’t tell you…….
|
Elevated conc.
But not cause |
|
|
Metabolic acid/base disorders result from a primary change in?
|
HCO3-
|
|
|
Respiratory acid/base disorders result from a primary disturbance in?
|
pCO2
|
|
|
What acid/base disorder results from a primary change in HCO3-
|
Metabolic disorders
|
|
|
What acid/base disorder results from a primary disturbance in pCO2?
|
Respiratory
|
|
|
What is Metabolic acidosis?
|
Too much H+ or lost of HCO3-
|
|
|
Example of Metabolic acidosis:
|
excess lactic acid production (exercise, or hypoxia)
or loss of bicarbonate (diarrhea, e.g.), |
|
|
3 types of Compensation of the Metabolic acidosis:
|
1. chemical buffering by plasma
2. Respiratory compensation: 3. Renal compensation |
|
|
Chemical Compensation of Metabolic acidosis is
|
chemical buffering by plasma
|
|
|
Metabolic acidosis is ____ HCO3- and ____ pH
|
Decrease HCO3-
Increase pH |
|
|
Respiratory Compensation of Metabolic acidosis,
Ventilatory rate changes with? |
Decrease pH ~~> ventilation (hyperventilation ~~> and decreased pCO2
|
|
|
Renal compensation of Metabolic acidosis involved in?
|
Restore HCO3- to plasma and also excrete H+ in urine
|
|
|
What is the end result of Renal compensation of Metabolic acidosis?
|
lower than normal pH, pCO2, HCO3-
|
|
|
A 21 year old man has had severe diarrhea for several days, and has been brought to the clinic by his concerned roommate. The physicians at the clinic find the following results from lab tests:
Arterial plasma pH ~ 6.98 Plasma [HCO3-] ~ 3 mmol/L pCO2 ~ 13 mmHg pH ~ (G/S/L) ~ normal HCO3- ~ (G/S/L) ~ normal pCO2 ~ (G/S/L) ~ normal Condition: Problem: Effect: |
pH ~ very less than ~ normal
HCO3- ~ less than ~ normal pCO2 ~ less than ~ normal Condition: Metabolic Acidosis Problem: HCO3+ Effect: pCO2 (Resp.) compensation) |
|
|
What is Metabolic alkalosis?
|
Too much HCO3- or too little H+
|
|
|
Condition: Metabolic alkalosis
Problem: Effect: |
Problem: increase in HCO3+
Effect: increase in pCO2 (Resp. compensation) |
|
|
Example of Metabolic alkalosis?
|
loss of acid by vomiting
|
|
|
During Respiratory Compensation of Metabolic alkalosis, ventilatory rate will _____ and pCO2 will ________.
|
Decrease
Decrease |
|
|
Renal response of Metabolic alkalosis will?
|
reduce plasma bicarbonate by secreting HCO3- into tubule lumen
|
|
|
Net result to renal response of Metabolic alkalosis?
|
higher than normal pH, pCO2, & HCO3-
|
|
|
Respiratory disorders with acid/base balance
|
Respiratory acidosis
Respiratory alkalosis |
|
|
Respiratory acidosis is caused by
|
Hypoventilation
|
|
|
What is Hypoventilation?
|
CO2 elimination rate < rate of CO2 production
which will increased pCO2 |
|
|
What is the Buffer Compensation for Respiratory acidosis:
|
Chemical buffering by the cells and plasma will change HCO3- by about 1mmol/L
For every 10mmHg change in pCO2 |
|
|
Chemical buffering by cells/plasma for Compensation for Respiratory acidosis:
will change HCO3- by about __ mmol/L for every ___ mmHg change in pCO2 |
1 mMol/L
10 mmHg |
|
|
If pCO2 has changed from 40 to 60mmHg, then these buffers by themselves will produce an
increase in HCO3- of? |
2mmol/L
slight increase in HCO3- |
|
|
Renal response to respiratory acidosis?
|
Decrease in plasma [HCO3-] by secretion
|
|
|
Net result of pCO2, HCO3-, and pH of renal response to respiratory acidosis?
|
higher than normal pCO2
higher than normal HCO3- lower than normal pH |
|
|
Respiratory alkalosis is caused by
|
Decreased CO2
|
|
|
What is Hyperventilation?
|
CO2 elimination rate < rate of CO2 production
which will increased pCO2 |
|
|
What is the Buffer Compensation for Respiratory alkalosis:
|
will change HCO3- by the change in pCO2
|
|
|
Chemical buffering by the cells and plasma for Compensation for Respiratory alkalosis:
will change HCO3- by about _ mmol/L For every __mmHg change in pCO2 |
1 mMol/L
10 mmHg |
|
|
Renal response to respiratory alkalosis?
|
Decrease plasma [HCO3-] by secretion
|
|
|
Net result of pCO2, HCO3-, and pH of renal response to respiratory alkalosis?
|
lower than normal pCO2
higher than normal pH (not completely compensated) lower than normal HCO3- |
|
|
The combination of pH, pCO2 and plasma[HCO3-] of acid/base balance signifies?
|
the type of disorder (acidosis vs. alkalosis),
the primary cause (respiratory vs. metabolic), and whether renal compensation has occurred. |
|
|
Respiratory
alkalosis pH ~ (G/S/L) ~ normal HCO3- ~ (G/S/L) ~ normal pCO2 ~ (G/S/L) ~ normal |
pCO2 ~ < normal
pH ~ > normal [HCO3-] ~ < normal |
|
|
Metabolic
alkalosis pH ~ (G/S/L) ~ normal HCO3- ~ (G/S/L) ~ normal pCO2 ~ (G/S/L) ~ normal |
pCO2 ~ > normal
pH ~ > normal [HCO3-] ~ > normal |
|
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Respiratory
acidosis pH ~ (G/S/L) ~ normal HCO3- ~ (G/S/L) ~ normal pCO2 ~ (G/S/L) ~ normal |
pCO2 ~~ > normal
pH ~ < normal [HCO3-] ~~ > normal |
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Metabolic
acidosis pH ~ (G/S/L) ~ normal HCO3- ~ (G/S/L) ~ normal pCO2 ~ (G/S/L) ~ normal |
pCO2 ~ < normal
pH ~ < normal [HCO3-] ~ < normal |
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Akalosis is either due to?
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a decreased pCO2,
or an increased plasma bicarbonate |
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Acidosis is either due to?
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an increased pCO2 or to a
decreased plasma bicarbonate |
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A 21 year old man has had severe diarrhea for several days, and has been brought to the clinic by his concerned roommate. The physicians at the clinic find the following results from lab tests:
Arterial plasma pH ~ 6.98 Plasma [HCO3-] ~ 3 mmol/L pCO2 ~ 13 mmHg pH ~ (G/S/L) ~ normal HCO3- ~ (G/S/L) ~ normal pCO2 ~ (G/S/L) ~ normal Condition: Problem: Effect: |
pH ~ Less than ~ normal
HCO3- ~ Less than ~ normal pCO2 ~ Less than ~ normal Condition: Metabolic Alkalosis Problem:HCO3- is lower than normal Effect: pCO2 is lower than normal |
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Mrs. Jones’ patient chart provides the following information:
Arterial plasma pH ~ 7.50 Plasma [HCO3-] ~ 20 mmol/L pCO2 ~ 30 mmHg What is her acid/base status? Acidosis or alkalosis? Respiratory or metabolic? |
pH ~ G ~ normal
HCO3- ~ L~ normal pCO2 ~ L ~ normal Alkalosis cause pH is greater than normal Respiratory |
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A young woman’s lab tests who the following:
Arterial plasma pH ~ 7.30 Plasma [HCO3-] ~ 36 mmol/L pCO2 ~ 60 mmHg What is her acid/base status? Acidosis or alkalosis? Respiratory or metabolic? |
pH ~ L ~ normal
HCO3- ~ G~ normal pCO2 ~ G ~ normal Acidosis cause pH is less than normal Respiratory |
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How to analyze these test result questions?
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1. examine the pH – determine if it is acidosis or alkalosis
2. examine the pCO2 – is it the primary cause, or a compensatory change? 3. Examine the magnitude of the difference of the HCO3- relative to normal A HCO3- change that exceed this is a sign of renal compensation |
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It is not uncommon for people to have acid-base disorders that are both?
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respiratory and metabolic
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people who have acid-base disorders that are both respiratory and metabolic tend to have?
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Many things not working
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