Acid Base Balance DSA's

Question 1

What is normal pHa?

Answer 1

Normal arterial pH = 7.4

Question 2

What is normal PaCO2?

Answer 2

Normal arterial CO2 = 40 mmHg (range is 38-42)

Question 3

What is normal arterial HCO3?

Answer 3

Normal arterial bicarbonate = 24 mEq/L (range is 22-28)

Question 4

How would a change in HCO3 be produced?

Answer 4

Metabolically, via the kidneys

Question 5

What is defined as blood acidosis?

Answer 5

pHa < 7.35

Question 6

What is normal PaO2?

Answer 6

Normal arterial oxygen = 80-100 mmHg (age dependent)

Question 7

What is defined as blood alkalosis?

Answer 7

pHa > 7.45

Question 8

What does an increase in bicarbonate do to the blood?

Answer 8

increases pHa (metabolic disturbance)

Question 9

What does a decrease in bicarbonate do to the blood?

Answer 9

decreases pHa (metabolic disturbance)

Question 10

What is the blood gas equilibrium equation?

Answer 10

CO2 + H2O -> H2CO3 -> H + HCO3

Question 11

What does an increase in CO2 do to the blood?

Answer 11

decreases pH (more CO2 means more carbonic acid and more H)

respiratory disturbance

Question 12

What does a decrease in CO2 do to the blood?

Answer 12

increases pH (less carbonic acid and less H)

respiratory disturbance

Question 13

Equation for acute respiratory acidosis

Answer 13

Expected [HCO3] = 24 + ((PaCO2 - 40) / 10)

Question 14

Equation for chronic respiratory acidosis

Answer 14

Expected [HCO3] = 24 + 4 ((PaCO2 - 40) / 10)

Question 15

Equation for acute respiratory alkalosis

Answer 15

Expected [HCO3] = 24 - 2 ((40 - PaCO2) / 10)

Question 16

Equation for chronic respiratory alkalosis

Answer 16

Expected [HCO3] = 24 - 5 ((40 - PaCO2) / 10)

Question 17

Metabolic acidosis if respiratory compensation is adequate

Answer 17

Expected PaCO2 = (1.5 [HCO3] + 8) +/- 2

Question 18

Metabolic alkalosis is respiratory compensation is adequate

Answer 18

Change in PaCO2 = (0.5 to 1) change in HCO3

Question 19

Osmolarity equation

Answer 19

Osmolarity = (2 x serum Na) + (BUN / 2.8) + (glucose / 18)

Question 20

Anion gap equation

Answer 20

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