Acid base balance

Question 1

What health probs lead to imballance?

Answer 1

Diabetes
COPD
Kidney disease

Question 2

Normal blood pH

Answer 2

7.35-7.45

less than that is acidosis
more than that is alkalosis

cant survive outside of 6.8-7.8

Question 3

3 mechanisms to regulate acid base ballance

Answer 3

buffer system
respiratory system
renal system

Question 4

Buffer system

Answer 4

• main regulator of acid base
• acts chemically to change strong acids to weak acids (also binds acids to neutralize them)
• respiratory and renal system needs to be functioning right

Question 5

Carbonic acid/ bicarbonate buffer

Other buffer systems

Answer 5

HCl + Na2CO3 –> NaCl + H2CO3
Strong acid + strong base is buffered into salt and weak acid

Phosphate, protein, hemoglobin, cellular (shifts H+ out of cell for K+)

Question 6

Respiratory system regulation

Answer 6

CO2 + H2O –> H2CO3 –> H+ + HCO3-

Respiratory center in medulla controls breathing
more breaths is more elimination of CO2
less breaths is CO2 retention

Question 7

Renal regulation

Answer 7

conserves bicarbonate and excretes some acid

3 mechanisms for acid excretion

• secrete free H+
• combine H+ with ammonia (NH3)
• Excrete weak acids

Question 8

Arterial Blood Gas (ABG) values for PaCO2, HCO3-, and PaO2

Answer 8

35-45 mm Hg
22-26 mEq/L
80-100 mm Hg

Question 9

ROME

Answer 9

Respiratory:
Opposite
-Alkalosis = high pH and low PaCO2
-Acidosis = low pH and high PaCO2

Metabolic:
Equal
-Acidosis = low pH and low HCO3-
-Alkalosis = high pH and high HCO3-

Question 10

Respiratory acidosis: causes and compensations

Answer 10

Carbonic acid excess caused by

• hypoventilation
• respiratory failure

Compensation
-kidneys conserve HCO3- and secrete H+ into urine

Question 11

Respiratory alkalosis: causes and compensation

Answer 11

Carbonic acid defecit caused by

• hypoxemia from acute pulmonary disorders
• hyperventilation

Compensation

• rarely occurs when acute
• can buffer with bicarbonate shift
• renal compensation if chronic

Question 12

Metabolic acidosis: causes, compensations, anion gap

Answer 12

excess carbonic acid or base bicarbonate defecit caused by:

• ketoacidosis
• lactic acid accumulation (shock)
• severe diarrhea
• kidney disease

compensatory mechanisms:

• increased CO2 excretion by lungs
• Kussmaul respirations (deep and rapid)
• kidneys excrete acid

Anion gap:
Na+- (Cl- + HCO3-)
normally 8-12 mmol/L but increases with acid gain

Question 13

Metabolic alkalosis: causes and compensations

Answer 13

Base bicarbonate excess caused by:

• prolonged vomitting or gastric suction
• gain of HCO3-

Compensatory mechanisms

• renal excretion of HCO3-
• Decreased respiratory rate to increase plasma CO2 (limited)