Acid/Base Balance

Question 1

Normal CO2 levels

Answer 1

35-45 mmHg

Co2 acts as an acid (H+ ion)

• Increased = resp acidosis
• Decreased = resp alkalosis

Question 2

Normal HCO3 levels

Answer 2

22-26 mEq

Bicarb is a BASE

• Increased bicarb = meta alkalosis
• Decreased bicarb = meta acidosis

Question 3

Respiratory acidosis

• causes
• compensations

Answer 3

Co2 > 45 mmHg (hypercapnia) and pH less than 7.4

Causes: suppression of breathing (i.e. COPD, pulmonary edema, chest wall excursion issues, etc)

Compensations: kidneys will conserve more bicarb ions (bicarb will be greater than 26 mEq)

Question 4

Respiratory alkalosis

• causes
• compensations

Answer 4

Co2 less than 35 mmHg, and pH greater than 7.4

Causes: hyperventilation, asthma attack, CHF

Compensation: kidney will excrete more bicarb while conserving H+ ions

Question 5

Metabolic acidosis

• causes
• compensations

Answer 5

Bicarb less than 22 mEq and pH less than 7.4

Causes: excess amount of ketones (diabetes), chloride or acid ions (vomiting, lactic acidosis)

Compensation: increase RR to get rid of Co2

Question 6

Metabolic alkalosis

• causes
• compensations

Answer 6

Bicarb > 26 mEq and pH > 7.4

Causes: excess indigestion of bicarb (antacids like Tums), loss of Cl ions

Compensation: respiratory system will decrease RR and hold onto more Co2
(Co2 > 45 mmHg)