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CRRAB II - Medicine > Acid-Base > Flashcards

Flashcards in Acid-Base Deck (27)
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0

What four steps should be taken to assess a patient with a pH disorder?

1. Determine acidosis or alkalosis
2. Determine anion gap
3. Determine osmol gap
4. Determine delta gap
5. Look at history and physical

1

What is normal pH?

7.40

2

What is the equation used to calculate anion gap?

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

3

What anion gap level is abnormal?

AG > 15

4

What equation is used to calculate serum osmolarity?

[Na]x2 + [Glucose]/18 + [BUN]/2.8

5

What is a normal osmolar gap?

Osm gap

6

How do you calculate the delta gap?

Add the osmolar gap to the measured bicarb. It should equal the amount of normal bicarb (24-26)

7

What does it mean if the delta gap is low?

Non-anion gap acidosis

8

What does it mean if there is an elevated delta gap?

Metabolic alkalosis

9

What are the potential causes of elevated anion gap acidosis?

MUDPILES
M: Methanol
U: Uremia
D: Diabetic/Alcoholic ketoacidosis
P: Paraldehyde
I: Iron or INH
L: Lactic acidemia
E: Ethylene glycol
S: Salicylate overdose

10

What are the most common causes of an elevated Osm gap with metabolic acidosis and increased anion gap?

Methanol, ethylene glycol, alcoholic ketoacidosis

11

What levels would you expect creatinine and BUN to be in uremia?

Creatinine: >5
BUN: >60
Anion gap rarely over 20

12

What are some causes of lactic acidosis?

Sepsis, CO or CN poisoning

13

How do you treat ethylene glycol poisoning?

medications, alcohol, dialysis

14

What are some causes of metabolic acidosis with a normal anion gap?

HARDASS
Hyperalimentation
Addison's disease
Renal tubular acidosis
Diarrhea
Acetazolamide
Spironolactone
Saline infusions

15

What do you give to someone with chloride responsive metabolic alkalosis?

Saline infusion

16

What are some causes of chloride responsive alkalosis?

Vomiting
Diuretics
NG suctioning
Cl wasting diarrhea (most diarrhea causes acidosis)
Villous adenoma

17

What is chloride unresponsive metabolic alkalosis usually due to?

Inappropriately high aldosterone levels

18

What can cause chloride unresponsive metabolic alkalosis?

Cushings
Hyperaldo including Barter's
CHF, CRF
Bicarb ingestion

19

What is the primary disturbance in respiratory acidosis?

Increased arterial CO2

20

What does acute compensation of respiratory acidosis look like?

Increase HCO3 by 1 mEq per increase of 10 mEq CO2

21

What does chronic compensation of respiratory acidosis look like?

Increase of 3 mEq HCO3 per increase of 10 mEq CO2

22

What are common causes of respiratory acidosis?

Airway obstruction
Lung - COPD (by far most common), Asthma, Pneumothorax, infection
CNS depression - sedatives, hypnotics, tumor
Neuromuscular weakness

23

What is the primary disturbance during respiratory alkalosis?

Decreased CO2

24

What does acute compensation of respiratory alkalosis look like?

HCO3 falls 2 mEq per decrease of 10 mEq CO2

25

What does chronic compensation of respiratory alkalosis look like?

HCO3 falls by 4 mEq per fall of 10 mEq of CO2

26

What are causes of respiratory alkalosis?

Anxiety
Aspirin, drugs, progesterone
Any cause of tachypnea (sepsis, fever, hypoxia)
Alcohol or narcotic withdrawal