Acid Base Balance

Question 1

What cause respiratory acidosis?

Answer 1

Anything that lead to (alveolar hypoventilation)

• primary pulmonary disease
• Neuromuscular disease
• CNS malfunction
• drug induced
• respiratory muscle fatigue

Question 2

What cause respiratory alkalosis?

Answer 2

Anything that lead to alveolar hyperventilation

• sepsis
• hypoxia “low tidal volume > tachypnea”
• mechanical ventilation
• liver disease “stage 2 - 3”
• hyperventilation syndrome

Question 3

What are the steps in acid base analysis?

Answer 3

• primary disturbance
• acute or chronic?
• anion gap
• compensation

Question 4

What are the values of metabolic, respiratory acidoses

Answer 4

PH <7.35

• respiratory: both HCO3 + PCO2 high
• metabolic: both HCO3 + PCO2 low

Question 5

What are the values of metabolic, respiratory alkalosis?

Answer 5

PH >7.35

• respiratory: both HCO3 + PCO2 low
• metabolic: both HCO3 + PCO2 high

Question 6

How to determine acute vs chronic respiratory acidosis disorder

Answer 6

Increment is always 10.

• PH: 0.3 in chronic - 0.8 in acute
• HCO3: 4 in chronic - 1 in acute.

Question 7

How to determine acute vs chronic respiratory alkalosis disorder

Answer 7

Increment is always 10.

• PH: 0.3 in chronic - 0.8 in acute
• HCO3: 5 in chronic - 2 in acute.

Question 8

What causes increase in anion gap?

Answer 8

• lactic acid
• ketoacid
• renal failure
• salicylate toxicity

Question 9

What causes normal anion gap?

Answer 9

• tubular acidosis
• hypercholermia
• diarrhea & fistula

Question 10

Appropriate compensation of metabolic acidosis

Answer 10

Winter’s formula
- PCO2: 1.5[HCO3] + 8 (+-) 2

If it’s more than the normal range
Then it’s mixed condition

Question 11

Differentiate between saline-sensitive and saline resistant metabolic alkalosis management:

Answer 11

If saline resistant: don’t give volume, only treat the cause

If saline sensitive: give volume

Question 12

What is saline sensitive and saline resistant characterized of

Answer 12

• sensitive: Hypokalemia + ECF contraction

- resistant: hypertension + ECF expansion

Question 13

What are the causes of saline resistant and saline sensitive metabolic alkalosis?

Answer 13

Sensitive: Vomiting - NG suction - over-diuretic - post hypercapnia

Resistant:

• hypertensive (Cushing, conns, RAS, renal failure)
• non hypertensive (hypokalemia, hypomagnesemia, batter’s, gittelman, licorice ingestion)
• exogenous steroid.

Question 14

What is the value of CL to determine saline resistant vs sensitive?

Answer 14

Cl >10 = resistant.

Question 15

what is winter formula, and why do we do it?

Answer 15

To assess if there’s another type of acidosis

PCO2= 1.5 [HCO3] +8 +-2

Question 16

What is the clinical presentation of respiratory acidosis?

Answer 16

• shallow breathing and hypoventilation
• cyanosis and pale
• dysrethmia
• headache
• drowsy and dizzy

Question 17

What are the clinical symptoms of respiratory alkalosis

Answer 17

• hyperventilation & deep breathing
• tachycardia
• hypokalemia
• seizure
• light headidness