Intern Year: Tintinalli- Section 3-Ch 19 Acid Base Disorders

Front 1

normal range for PCO2?

Back 1

35-45

Front 2

how do you calculate the anion gap (AG)?

Back 2

AG= [Na+] - ([HCO3-] + [Cl-])

Front 3

if a patient has hyperglycemia, should you correct Na when calculating the AG?

Back 3

No

similarly will dilute the Cl ions

remember:
AG= [Na+] - ([HCO3-] + [Cl-])

Front 4

normal anion gap value?

Back 4

12 +/- 4

Front 5

an anion gap of what value is abnormal, even without previous comparison value

Back 5

>15 mEq

Front 6

give a few examples of what can cause a HIGH anion gap WITHOUT an acid-base disturbance

Back 6

the cause is decreased unmeasured cations

so

Hypomagnesmia
Hypokalemia
Hypocalcemia

Front 7

give a few examples of what can cause a LOW anion gap WITHOUT an acid-base disturbance

Back 7

this is caused due to increased unmeasured cations or decreased unmeasured anions, or measurement confounders

High lithium
Hypoalbumin, hypogammaglobulin
Bromide, high TGs

Front 8

causes of elevated anion gap and metabolic acidosis

Back 8

MUDPILES

Methanol
Uremia (renal failure)
DKA
Paraldehyde
Infection
Lactic acidosis
Ethylene glycol
Salicilates

Front 9

if you suspect ketoacidosis, what are 3 causes, their associated anion species and the diagnostic adjunct that can help you

Back 9

Diabetic: B-Hydroxybuterate

Alcoholic: Acetoacetate

Starvation:

adjunct- Serum/urine ketones

Front 10

Methanol is an exogenous poison that can cause elevated AG metabolic acidosis. What diagnostic adjunct can be used to recognize it?

Back 10

Osmolal gap

Front 11

Ethylene glycol is an exogenous poison that can cause elevated AG metabolic acidosis. What diagnostic adjunct can be used to recognize it?

Back 11

Osmolal gap

oxylate crystals (urine)

Front 12

metabolic acidosis + concomitant resp alk and met alk =?

Back 12

Salicylate poison

Front 13

anion gap of >30 normally indicates one of two things..

those are?

Back 13

DKA or lactic acidosis

Front 14

remember that although you can have a lactic acidosis as the primary acid base manifestation....

flip card

Back 14

IT IS NOT THE PRIMARY CLINICAL PROBLEM

Front 15

the change in value of the anion gap (the Delta Gap) should be exactly equal to what?

Back 15

the decrease in HCO3-

this is a one to one relationship

Front 16

with normal respiratory compensation, PCO2 falls by __ mmHg for every 1 mEq/L fall in HCO3

Back 16

PCO2 falls by 1mm Hg

per 1 drop in HCO3

Front 17

what therapy should be considered if pH drops below 7.1?

Back 17

bicarb

this is because respiratory minute volume declines when pH decreases below this

Front 18

Pt with pH<7.5

HCO3 is low

Wide Anion Gap

what should you check?

Back 18

change in increase of AG

versus

change in decrease in bicarb

(delta AG/delta HCO3)

Front 19

Pt with pH<7.5

HCO3 is low

Wide Anion Gap

increase in AG is greater than decrease in Bicarb

disturbance?

Back 19

Metabolic acidosis + Metabolic alkalosis

Front 20

Pt with pH<7.5

HCO3 is low

Wide Anion Gap

increase in AG equals decrease in Bicarb

disturbance?

Back 20

Pure metabolic acidosis (wide AG)

Front 21

Pt with pH<7.5

HCO3 is low

Wide Anion Gap

increase in AG is less than decrease in Bicarb

disturbance?

Back 21

Normal AG metabolic acidosis

Front 22

Pt with pH<7.5

HCO3 is low

you check the change in decrease of PCO2 and change in decrease of HCO3

if delta decrease of PCO2 > delta decrease HCO3

what is the disturbance?

Back 22

Metabolic acidosis

plus

respiratory alkalosis

Front 23

Pt with pH<7.5

HCO3 is low

you check the change in decrease of PCO2 and change in decrease of HCO3

if delta decrease of PCO2 = delta decrease HCO3

what is the disturbance?

Back 23

Metabolic acidosis

with normal respiratory compensation

Front 24

Pt with pH<7.5

HCO3 is low

you check the change in decrease of PCO2 and change in decrease of HCO3

if delta decrease of PCO2 < delta decrease HCO3

what is the disturbance?

Back 24

Metabolic acidosis

plus

respiratory acidosis

Front 25

Pt with pH<7.5

PCO2>40

you check the change in increases of H+ and change in increase of PCO2

if >0.8

what is the disturbance?

Back 25

Respiratory acidosis

plus metabolic acidosis

change in hydrogen ion conc is larger than accounted for by acute or chronic chang in PCO2

Front 26

Pt with pH<7.5

PCO2>40

you check the change in increases of H+ and change in increase of PCO2

if 0.8

what is the disturbance?

Back 26

Acute respiratory acidosis

change in hydrogen ion con matches acute change in PCO2

Front 27

Pt with pH<7.5

PCO2>40

you check the change in increases of H+ and change in increase of PCO2

if 0.8-0.33

what is the disturbance?

Back 27

Acute or chronic respiratory acidosis

change in hydrogen ion concentation is larger than accounted for by chornic change in PCO2. Chronic resp acidosis plus either acute resp alk or met acidosis is present

Front 28

Pt with pH<7.5

PCO2>40

you check the change in increases of H+ and change in increase of PCO2

if 0.33

what is the disturbance?

Back 28

Chronic resp acidosis

change in hydrogen ion conc matches chronic change in PCO2

Front 29

Pt with pH<7.5

PCO2>40

you check the change in increases of H+ and change in increase of PCO2

if <0.33

what is the disturbance?

Back 29

Respiratory acidosis + metabolic alkalosis

change in hydrogen ion conc is less than accounted for by chrnonic change in PCo2

Front 30

7.35 < pH < 7.45

PCO2 and HCO3 are down

what is the disturbance

Back 30

Metabolic acidosis and Respiratory alkalosis

Front 31

7.35 < pH < 7.45

PCO2 and HCO3 are increased

what is the disturbance

Back 31

Metabolic alkalosis and respiratory acidosis

Front 32

7.35 < pH < 7.45

PCO2 and HCO3 are normal

Delta anion gap is increased

what is the disturbance

Back 32

Wide AG type metabolic acidosis and metabolic alkalosis

Front 33

on page 107 there are more algorithm type questions that could be made for mixed alkalosis...but i'm not sure how important memorizing the numbers are so for now im not making them

Back 33

up to you

Front 34

what is the lowest PCO2 level achievable in spontaneous respiration?

Back 34

12mm Hg

Front 35

in general, for each 0.1 decrease in the pH, serum K will (increase/decrease) by approximately ___ mEq/L

Back 35

Increase 0.5mEq

the movement of H+ into cells is associated with extrusion of K+

Front 36

a low or normal serum K in a pt with acidosis reflects what?

Back 36

severe intracellular K+ depletion

Front 37

many patients with type B lacitc acidosis (normal tissue oxygenation and impairment of lactate use) have what underlying disease?

Back 37

liver disease

conversion of lactate to pyruvate in the liver requires NAD

like in an etoh user, metabolism of ethanol has left little NAD available to convert lactate to pyruvate

Front 38

according to the book, what is used to identify a wide anion gap acidosis?

Back 38

analyzing simple venous electrolytes

ABG is not needed

Front 39

elevated osmol gaps are seen in what?

Back 39

methanol and ethylene glycol poisoning

Front 40

T/F

Ethanol can be attributed as a cause of any significant metabolic acidosis

Back 40

FLASE

Front 41

the triple acid base disturbance of :

Wide AG metabolic acidosis
Metabolic alkalosis
respiratory alkalosis

is seen in what 2 things?

Back 41

sepsis (lactic acidosis)

salicylate poisoning

Front 42

what is the most apporpriate first tx for an acidosis

Back 42

correct the respiratory problem

of course assuming there is inadequate respiratory complensation

Front 43

what treatment should be avoided in ED tx of mild/moderate metabolic acidosis

Back 43

bicarb

Front 44

when HCO3 is used, administer ___ mEq/kg for each milliequivalent per liter desired rise in HCO3

Back 44

0.5

Front 45

3 indictinos for use of bicarb in metabolic acidosis

Back 45

Severe hypobicarbonatemia (<4mEq)

severe acidemia (pH<7.2) with signs of shock or myocardial irritability that is not rapidly responsive to supportive measures including adequate ventilation

severe hypercholoremic acidemia

Front 46

what are some of the consequences of alkalosis

Back 46

neurological abnormalities

tetany

neruomuscular instability

seizures

Front 47

why is Alkalemia of particular concern in COPD pts?

Back 47

the O2 shift to the left makes O2 less available to tissues

Front 48

each 1mmHg increase in PCO2 results in a 1 mmol increase in H+

threefore if the H+ is higher or lower than that suggested by the change in the PCO2, what is going on

Back 48

there is a mixed disorder present

Front 49

when evaluating change in H with change in PCO2 if the ratio is

0.3 = ?

0.8= ?

Back 49

0.3 = chronic resp acidosis

0.8= acute resp acid

other ratios suggest mixed

Front 50

reduce the arterial PCO2 by no more than ___ mmHg


why?

Back 50

5

rapid correction can cause severe combined metabolic and resp alkalosis and cardiac dysrhythmia

rapid rise in pH can cause hypocalcemia dn hypokalemia iwth dysrhthmia, seizure, etc