Renal Control of Acid-Base Balance Flashcards
1
Q
- Volatile reactions that occur in the body
A
- Aerobic glucose metabolism
- Fat metabolism
- Aerobic glucose metabolism
2
Q
- Fixed reactions that occur in the body
A
- Cysteine metabolism
- Phosphoprotein metabolism
3
Q
- An increase in 0.3 pH _ H+ concentration
A
- Halves (pH and concentration of H+ are inversely related)
4
Q
- Arterial blood H+ concentration
- Arterial blood H+
A
- 4.0 x 10-5
- 7.40
5
Q
- Venous blood H+ concentration
- Venous blood pH
A
- 4.5 x 10-5
- 7.35
6
Q
- Interstitial fluid H+ concentration
- Interstitial fluid pH
A
- 4.5 x 10-5
- 7.35
7
Q
- Intracellular fluid H+ Concentration
- Intracellular pH
A
- 1 x 10-3 to 4 x 10-5
- 6.0-7.4
8
Q
- Urine H+ Concentration
- Urine pH
A
- 3 x 10-2 to 1 x 10-5
- 4.5-8.0
9
Q
- What are the buffer systems of the body?
A
- Bicarbonate
- Hemoglobin
- Phosphate
- Plasma Proteins
10
Q
- What is the pK of the bicarbonate buffer system?
- What does this represent?
A
- 6.1
- Half of the solution is H+ and half is H2CO3
11
Q
- What organs play a role in the buffer system?
A
- Lungs
- Kidney
- Bone
12
Q
- H+ ions can be buffered by
A
- Plasma proteins
- Hemoglobin
13
Q
- If acidemia occurs, ICF does what to H+?
A
- Takes in H+
- Cell will take in H+ and kick K+ out of the cell
14
Q
- If alkalemia occurs, ICF does what to H+?
A
- ICF donates H+
- H+ raised in ECF
- Lower ECF K+ by bringing it into cells
15
Q
- How does an increase in alveolar ventilation change pH?
A
- An increase in alveolar ventilation increases pH
16
Q
- Of the bicarbonate filtered by the kidney, _ % is reabsorbed
- Where does reabsorption of HCO3- occur?
A
99.9%
- Reabsorption occurs in
- PCT (85%)
- Thick Ascending Limb of LOH (10%)
- Collecting Duct (>4.9%)
17
Q
- How is bicarb reabsorbed in the proximal tubule?
A
- Na+/H+ exchanger on the APICAL membrane pumps H+ into tubular fluid
- H+ will combine with the HCO3- that has been filtered into the glomerulus
- Via Carbonic acid, H2CO3 will be converted to H2O and CO2
- H2O and CO2 will diffuse into the cell
- Will combine AGAIN via carbonic anhydrase INTRACELLULARLY
- H+ will be recycled back into tubular fluid
- HCO3- will be reabsorbed via:
- Na+/3HCO3- cotransporter on basolateral membrane
- HCO3-/Cl- antiporter on basolateral membrane
18
Q
- How does phosphate buffering of secreted H+ ions work?
- What does this buffer system help regenerate?
A
- NaHPO4- in the tubular lumen combines with H+ that is secreted into the tubular lumen via that Na+/H+ exchanger on the basolateral membrane
- This buffers the H+ ion and then NaH2PO4 is eliminated in the urine
- Buffering of secreted H+ regenerates that plasma HCO3- that has been consumed elsewhere when the NaH2PO4 lost an H+ to a less acidid body compartment and now carries the H+ into the urine
20
Q
- Production, Transport, and Excretion of Ammonia by the Nephron for Generation of New Bicarbonate
A
- Ammonium is transported by the NKCC in the TAL of the LOH on the APICAL membrane
- It replaces K+ and diffuses into the cell where it is “ion trapped”
21
Q
- Alpha intercalated cells are present in the _
- They are responsible for the _ of H+ and _ of HCO3-
A
- Collecting Ducts
- SECRETION
- REABSORPTION
22
Q
- Beta intercalated cells are present in the _
- They are responsible for the _ of H+ and the _ of HCO3-
A
- Collecting duct
- Reabsorb H+
- Secrete HCO3-
26
Q
- How do you calculate NAE?
A
*
27
Q
- What is an Acid-Base Nomogram
A
- Superimposed on Davenport DIagram Depicting HCO3, pH and PCO2
30
Q
- Causes of non-anion gap metabolic acidosis
A
- HARDUPS
- H=Hypealimentation
- A=Acetazolamide
- R=Renal Tubular Acidosis
- D=Diarrhea
- U=Uretero-Pelvic Shunt
- P=Post-Hypocapnia
- S=Spironolactone
32
Q
- Type I RTA
A
- Distal tubules
- Acidosis
- Hypokalemia
- Failure of alphaH+ secretion by the intercalated cells
33
Q
- Type 2 RTA
A
- Occurs in the proximal tubule as a failure of the HCO3- channel on the basolateral surface to function, impairing HCO3- reabsorption
- Now there is no bicarb buffer
- Acidosis
- Hypokalemia
34
Q
- Type 4 RTA
A
- Adrenal gland is not synthesizing aldosterone
- HIGH K+
- Decreases NH3 synthesis by the PT
36
Q
- Causes of metabolic alkalosis
A
- CLEVER PD
- C-Volume Contraction
- L-Licorice
- E-Endo (Conn, Cushing, [Bartter])
- V-Vomiting
- E-Excess Alkali
- R-Refeeding Alkalosis
- P-Post-hypercapnia
- D-Diuretics
39
Q
- Causes of respiratory acidosis
A
- CANS
- C-CNS depression
- A-Airway Obstruction
- N=Neuromuscular Disorders
- S=Severe pneumonia,embolism, edema
Chronic
COPD
Any disease leading to imparied ventilation
41
Q
- Causes of respiratory alkalosis
A
- CHAMPS
- C=CNS Disease
- H=Hypoxia
- A=Anxiety
- M=Mechanical Ventilators
- P=Progesterone
- S=Salicylates, Sepsis
43
Q
A
