UNMC Nursing Pathophysiology 2 Exam 4
pH ratio - ANS-bicarbonate/carbonic acid (base/acid)
Three Mechanisms Regulating Acid-Base Balance - ANS-1. Plasma buffer system
2. Respiratory system
3. Renal system
Plasma buffer systems - ANS-work fast!
-HCO3-, H2CO3
-protein buffers
-phosphate
-cellular ion exchange mechanism
How does the respiratory system regulate acid-base balance? - ANS-Regulate retention
or elimination of CO2 through changes in rate of ventilation.
How does the renal system regulate acid-base balance? - ANS-kidneys either reabsorb
or secrete more bicarbonate or hydrogen ions
normal blood pH - ANS-7.35-7.45
normal pCO2 - ANS-35-45
normal HCO3 - ANS-22-28
Etiology of respiratory acidosis - ANS-anything depressing ventilation or gas exchange,
respiratory disorder, lung disease
Initial ABGs respiratory acidosis - ANS-pH: Low (<7.35)
pCO2: High (>45)
HCO3: Normal (22-28)
Compensated ABGs respiratory acidosis - ANS-pH: on the low end of normal
(7.35-7.40)
pCO2: High (>45)
HCO3: High (>28)
, How is respiratory acidosis corrected? - ANS-by kidneys= retain (reabsorb) more
HCO3- and excrete H+
Respiratory alkalosis etiology - ANS-hyperventilation (blowing off too much CO2)
Initial ABGs respiratory alkalosis - ANS-pH: High (>7.45)
pCO2: Low (<35)
HCO3: Normal (22-28)
Compensation in respiratory alkalosis - ANS-By kidneys, retain (reabsorb) more H+ and
excrete more HCO3-
Compensated ABGs respiratory alkalosis - ANS-pH: on the high end of normal
(7.40-7.45)
pCO2: Low (<35)
HCO3: Low (<22)
Metabolic acidosis etiology (5) - ANS-loss of base or gain of acid
1. renal failure (unable to retain HCO3-)
2. lactic acidosis
3. Diabetic ketoacidosis
4. diarrhea
5. ingestion of acids
Initial ABGs metabolic acidosis - ANS-pH: Low (<7.34)
pCO2: Normal (35-45)
HCO3: Low (<22)
Compensation in metabolic acidosis - ANS-By lungs, hyperventilate to blow off acidic
CO2 (Kussmall's)
Compensated ABGs metabolic acidosis - ANS-pH: on the low end of normal (7.35-7.40)
pCO2: Low (<35)
HCO3: Low (<22)
Metabolic alkalosis etiology - ANS-loss of metabolic acids, excess HCO3- intake
Initial ABGs metabolic alkalosis - ANS-pH: High (>7.45)
pCO2: Normal (35-45)
HCO3: High (>28)
pH ratio - ANS-bicarbonate/carbonic acid (base/acid)
Three Mechanisms Regulating Acid-Base Balance - ANS-1. Plasma buffer system
2. Respiratory system
3. Renal system
Plasma buffer systems - ANS-work fast!
-HCO3-, H2CO3
-protein buffers
-phosphate
-cellular ion exchange mechanism
How does the respiratory system regulate acid-base balance? - ANS-Regulate retention
or elimination of CO2 through changes in rate of ventilation.
How does the renal system regulate acid-base balance? - ANS-kidneys either reabsorb
or secrete more bicarbonate or hydrogen ions
normal blood pH - ANS-7.35-7.45
normal pCO2 - ANS-35-45
normal HCO3 - ANS-22-28
Etiology of respiratory acidosis - ANS-anything depressing ventilation or gas exchange,
respiratory disorder, lung disease
Initial ABGs respiratory acidosis - ANS-pH: Low (<7.35)
pCO2: High (>45)
HCO3: Normal (22-28)
Compensated ABGs respiratory acidosis - ANS-pH: on the low end of normal
(7.35-7.40)
pCO2: High (>45)
HCO3: High (>28)
, How is respiratory acidosis corrected? - ANS-by kidneys= retain (reabsorb) more
HCO3- and excrete H+
Respiratory alkalosis etiology - ANS-hyperventilation (blowing off too much CO2)
Initial ABGs respiratory alkalosis - ANS-pH: High (>7.45)
pCO2: Low (<35)
HCO3: Normal (22-28)
Compensation in respiratory alkalosis - ANS-By kidneys, retain (reabsorb) more H+ and
excrete more HCO3-
Compensated ABGs respiratory alkalosis - ANS-pH: on the high end of normal
(7.40-7.45)
pCO2: Low (<35)
HCO3: Low (<22)
Metabolic acidosis etiology (5) - ANS-loss of base or gain of acid
1. renal failure (unable to retain HCO3-)
2. lactic acidosis
3. Diabetic ketoacidosis
4. diarrhea
5. ingestion of acids
Initial ABGs metabolic acidosis - ANS-pH: Low (<7.34)
pCO2: Normal (35-45)
HCO3: Low (<22)
Compensation in metabolic acidosis - ANS-By lungs, hyperventilate to blow off acidic
CO2 (Kussmall's)
Compensated ABGs metabolic acidosis - ANS-pH: on the low end of normal (7.35-7.40)
pCO2: Low (<35)
HCO3: Low (<22)
Metabolic alkalosis etiology - ANS-loss of metabolic acids, excess HCO3- intake
Initial ABGs metabolic alkalosis - ANS-pH: High (>7.45)
pCO2: Normal (35-45)
HCO3: High (>28)
