Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
43 Cards in this Set
- Front
- Back
What are the 5 major buffer systems?
|
1. Carbonic acid/Bicarb (plasma and cells)
2. Protein (plasma) 3. Hemoglobin (RBCs) 4. Phosphate (plasma/cells/urine) 5. Ammonia (urine) |
|
What buffer is the major extracellular buffer?
|
Bicarb
|
|
What buffer is the major intracellular?
|
Hemoglobin
|
|
-What protein is the main protein buffer?
-How does it buffer? |
Albumin; via the imidazole group of histidine
|
|
Which buffers do/can buffer base?
|
Bicarbonate and Phosphate
|
|
What is the normal Base:acid ratio in the hh eqn?
|
20:1
|
|
Which component in the HH eqn reflects renal changes? Which reflects respiratory changes?
|
Renal = top metabolic HCO3
Resp = lower respirty CO2 |
|
In the bicarb buffer system:
-What shifts rxtn to left? -What shifts rxtn to right? |
Left: increase in acid
Right: increase in base (these are the body RESPONSES) |
|
What is INTERACTION REACTION?
|
The term for when other conjugate bases act in concert with the bicarb sytem
|
|
What detects changes in pCO2?
|
-Chemoreceptors in medulla
-Aortic/carotid bodies |
|
How does respiration change in
-Metabolic acidosis? -Metabolic alkalosis? |
Acidosis: increase respirations to blow off CO2
Alkalosis: depress respiratns to increase CO2 |
|
What is the relationship between pO2 and pCO2?
|
As PCO2 increases, pO2 decreases and vice versa
|
|
What is the Bohr effect?
|
Shifting of O2 diss. curve based on acid/base conditions.
|
|
How does the Hb curve shift:
-in Acid? -in Base? |
Acid: shift to right
Base: shift to left |
|
What is the Haldane effect?
|
the effect of pCO2 on the Hb-O2 dissociation curve.
|
|
How does the O2 diss curve shift with
-Increased CO2? -Decreased CO2? |
Incr. CO2 = shift to right (acidosis)
Decr. CO2 = shift to left |
|
What happens to Hb's O2 affinity when curve shifts
-To the right? -To the left? |
Right = decreased affinity - lose oxygen more easily
Left = increased affinity - harder to give oxygen to tissue |
|
How does CO2 enhance oxygen release from hemoglobin?
|
By binding alpha amino groups of N-terminal valines on both Alpha and Beta chains
|
|
How does 2,3-DPG enhance O2 release from hemoglobin?
|
By binding alpha amino groups of N-terminal valines on ONLY Beta chains.
|
|
On a Hb molecule:
-Where does O2 bind? -Where does H+ bind? |
-O2 binds Iron group
-H+ binds imidazole group of histidine (similar to acid buffing by albumin) |
|
What is oxidized Hb bound to?
-Oxygen? -Hydrogen? |
Hydrogen; oxygenated hemoglobin is not denoted as oxidized.
|
|
What enzyme keeps hemoglobin in its reduced state?
|
Methemoglobin reductase, which requires NADH
|
|
What is the function of the ISOHYDRIC shift?
|
To remove excess CO2 from the tissues after Hb delivers O2.
|
|
What is the function of the Chloride shift?
|
To maintain the RBC's electronegativity while buffering.
|
|
How does the Isohydric shift work?
|
1. O2 is delivered
2. CO2 diffuses into RBC 3. CO2 + H2O = H2CO3 = H+ and HCO3- 4. H+ binds naked Hgb 5. HCO3- diffuses out of RBC. |
|
How does the Chloride shift work?
|
When HCO3 diffuses out of RBC, CL- diffuses in to balance the cell's ionic state.
|
|
What pH state will produce
-Hyperkaluria? -Hypokaluria? |
Hyper K+ from Acidosis
Hypo K+ from Alkalosis |
|
Where does bicarb reabsorption occur in the kidney?
|
Proximal tubule
|
|
Where does conjugate acid secretion take place in the kidney?
|
-Distal tubule
(ammonia/phosphate) |
|
what is the pH limit of acidotic urine?
|
4.5
|
|
What 2 processes for H+ excretion occur in the distal tubule?
|
-Ammonia
-Titratable acid - Phosphate |
|
What kidney response to Acid is:
-Immediate short term response -Slow, long-term response? |
Immediate = Phosphate titratable acid.
Slow = Ammonium ion excretion |
|
What is the major indicator of a RESPIRATORY disturbance?
|
PCo2
|
|
What is the primary indicator of a METABOLIC disturbance?
|
HCO3
|
|
When is BE more off; in respiratory or metabolic disturbance?
|
Metabolic;
Acidosis = --BE Alkalosis = ++BE |
|
In what 3 conditions is resp alkalosis seen in?
|
1. Hyperventilation
2. Salicylate toxicity 3. Cirrhosis |
|
In what 3 conditions is metabolic alkalosis seen in?
|
1. Vomiting - K depletion
2. Diuretic long-term use 3. Cushing's disease |
|
In what 3 conditions is Resp acidosis seen?
|
1. Central/peripheral resp failure
2. Emphesema 3. Barbiturate toxicity |
|
In what 3 conditions is Metab acidosis seen?
|
1. Diabetic coma
2. Renal failure 3. Diarrhea w/ pyloric obstruction |
|
What is the treatment for Respiratory Acidosis?
|
Increase respirations to blow off CO2
|
|
What is treatment for Resp alkalosis?
|
Breathe into bag to increase co2
|
|
What is the treatment for Metabolic Acidosis?
|
Give bicarb viat lactate/citrate ringers
|
|
What is the treatment for Metabolic Alkalosis?
|
Give salt - NaCl, KCl, or NH4Cl to acidify the kidney and induce loss of bicarb.
|