Acid-Base - Wall

Question 1

What are the two main categories of acids?

Answer 1

carbonic acid and non-carbonic acids

Question 2

what is the key organ for acid removal? how much does it eliminate per day?

Answer 2

the lungs

15,000 mmol/d

Question 3

What is the main form of elimination of non-carbonic acids?

Answer 3

the kidneys

Question 4

how much non-carbonic acids are eliminated each day?

Answer 4

50-100 meq/d

Question 5

what are the extremes of ph compatible with human life?

Answer 5

6.8-7.8

Question 6

what is the normal plasma bicarbonate concentration?

Answer 6

24 meq/l

Question 7

in terms of pH levels, define the following:

acidemia
alkalemia

Answer 7

acidemia - reduced pH

alkalemia - increased pH

Question 8

What is the chemical equation for the bicarbonate buffer system?

Answer 8

CO2 + H20 <> H2CO3 <> H+ + HCO3-

Question 9

what is the normal HCO3?

Answer 9

24

Question 10

what equation did he list as the determinants of pH, showing why only 4 cardinal acid-base disorders?

Answer 10

(pH) x H = 24 x CO2 / HC03

Question 11

How can you estimate the H concentration from the pH?

Answer 11

[H] = 80 - decimal digits of pH

Question 12

What is the normal:

pH

pCO2

HCO3

Answer 12

pH - 7.4

pCO2 - 36-44 mm Hg

HCO3 - 22-26 meq/L

Question 13

In metabolic acidosis, do you have increased or decreased bicarbonate?

Answer 13

decreased bicarbonate

Question 14

In metabolic alkalosis, increased or decreased bicarbonate?

Answer 14

increased bicarbonate

Question 15

In respiratory acidosis, do you have increased or decreased C02?

Answer 15

Increased c02

Question 16

in respiratory alkalosis, do you have increased or decreased c02?

Answer 16

decreased

Question 17

What is the major extracellular buffer?

Answer 17

hco3

Question 18

do buffers have an immediate or delayed effect?

Answer 18

immediate

Question 19

what si the isohydric principle?

Answer 19

all buffers change in the same directoin

Question 20

Where are the following buffer systems seen in the body:

bicarbonate
phosphate
ammonia
protein

Answer 20

bicarbonate - ecfv
phosphate - urine
ammonia - urine
protein - non-specific

Question 21

What are secondary, compensatory mechanisms for acid-base disorders?

Answer 21

Lungs - start helping instantly

Kidneys - slower but more powerful than lungs

Question 22

How do you lungs compensate for metabolic disorders?

Answer 22

altering c02 levels

Question 23

how do the kidnesy correct respiratory disorders?

Answer 23

alterations in bicarbonate levels (1-2 days)

Question 24

Explain the four stages of buffer mechanisms in order of soonest to last

Answer 24

Buffer systems (primarily bicarb.) ECF, immediate

Increased rate & depth of breath to decrease co2 - Lungs - minutes to hours

Buffers of phosphate, protein and bicarb - Intracell Fluid - 2-4 horus

Hydrogen Ion excretion, bicarb reabsorption and bicarb generation - kidneys - hours to days

Question 25

What do the pH, HCO3 and pCO2 do in metabolic acidosis?

Answer 25

``` pH decreases HCO3 decreases (primary) pCO2 decreases (compensatory) ```

Question 26

What do the pH, HCO3 and pCO2 do in metabolic alkalosis?

Answer 26

``` pH increases HC03 Increases (primary) pCO2 increases (compensatory) ```

Question 27

What do the pH, HCO3 and pCO2 do in respi. acidosis?

Answer 27

``` pH decreases hc03 increases (compensatory) pc02 increases (primary) ```

Question 28

What do the pH, HCO3 and pCO2 do in resp alkalosis?

Answer 28

``` ph INCREASES hco3 decreases (compensatory) pco2 decreases (primary ```

Question 29

What are the golden rules of simple acid-base disorders?

Answer 29

1. pC02 and HC03 always change in the same direction 2. The secondary physiologic compensatory mechanisms must be present 3. The ompensatory mechanims never fully correct pH

Question 30

What is metabolic acidosis?

Answer 30

process that reduces plasma bicarbonate concentration

Question 31

What is the etiology of metabolic acidosis?

Answer 31

decreased renal acid excretion, direct bicarbonate losses or increased acid generation (ie aspirin or methanol) (i.e. lactic acid and ketoacid)

Question 32

What are the ways you can get decreased acid excretion?

Answer 32

renal failure/reduced gfr (leadings to decreased ammonium excretion) type I distal renal tubular acidosis type 4 renal tubular acidosis (hypoaldosteronism)

Question 33

What induces respiratory acidosis?

Answer 33

hypercapnia (decreased alveolar ventilation)

Question 34

what are the actions of the buffering mechanisms in respiratory acidosis?

Answer 34

raise plasma bicarbonate (compensatory) it's a rapid but limited response kidneys then minimize change in extracellular pH by increasing acid excretion generating new bicarbonate ions (delayed response)

Question 35

what are some acute causes of respiratory acidosis?

Answer 35

``` general anasthesia sedative overdose cardiac arrest pneumothorax pneumonia basically anything that results in decreased oxygen intake that'll cause a build up of lactic acid ```

Question 36

what are chronic causes of respiratory acidosis?

Answer 36

``` obstructive pulmonary disease primary alveolar hypoventilation brain tumor respiratory nerve damage scleroderm prolonged pneumonia ```

Question 37

what is the common reason for respiratory alkalosis?

Answer 37

too much breathing | reduced co2 due to increased alveolar ventilation

Question 38

what does the buffering process do in respiratory alkalosis?

Answer 38

lowers plasma bicarb concentration (rapid but limited response) kidney response is to reduce net acid excretion (delayed 1-2 days)

Question 39

what are causes of respiratory alkalosis?

Answer 39

``` anxiety, hysteria fever cns disease congestive heart failure hypoxia ```

Question 40

do acute or chronic respiratory acid base disorders cause a great change in the pH?

Answer 40

acute (kidney hasn't had the time to compensate)

Question 41

How does plasma Cl- change in relation to plasma HCO3

Answer 41

Equally but inversely

Question 42

Does the plasma anion gap change with respiratory disorders?

Answer 42

no

Question 43

how is plasma sodium affected by respiratory disorders?

Answer 43

it is not directly altered

Question 44

what occurs in metabolic alkalosis?

Answer 44

raising of the plasma bicarb concent

Question 45

what is the etiology of metabolic alkalosis?

Answer 45

loss of hydrogen ion from the GI tract (vomiting) or into the urine (diuretic therapy) or through xs acid excretion

Question 46

what are the major causes of metabolic alkalosis?

Answer 46

GI loss (vomiting) or urinary loss (thiazide type diuretics)

Question 47

because bicarbonate is raised in metabolic alkalosis, what is necessarily decreased that isn't part of the overall important chemical equation?

Answer 47

chlorine

Question 48

when you have been vomiting and excreting pure hcl, what is the urine concentration going to be of chlorine?

Answer 48

it will be extremely low because they will want to keep everything that they can.

Question 49

What causes an increased plasma anion gap?

Answer 49

when the A- is reabsorbed by the kidneys and reatined in the plasma, as an unmeasured anion

Question 50

what causes a normal anion gap?

Answer 50

when the A- is filtered and excreted by the kidneys

Question 51

What makes up the majority of the unmeasured cations?

Answer 51

albumin, normally around 10 meq/L

Question 52

what can cause an increase anion gap?

Answer 52

renal failure - phosphate, sulfate urate hippurate

Question 53

where does final excretion of daily acid load occur priamrily?

Answer 53

in the collecting duct

Question 54

what is the law of electroneutrality?

Answer 54

if sodium concentration stays constant but chloride conc changes, an acid base disorder is present

Question 55

t or f: sodium concentration is directly altered by an acid-base disorder

Answer 55

fasle, sodium conc is not directly altered by acid base disorder

Question 56

t or f: chlorine is altered in all acid base disorders (except decreased plasma anion gap metabolic acidosis)

Answer 56

false: chlorine concentration is altered in all acid-base disordes except with DECREASED plasma anion gap metabolic acidosis