Acid-Base Balance

Question 1

Exposure of normal arterial blood sample to room air: PO2 ____, PCO2 ____, ph _____

Answer 1

Increased; decreased; increased

Question 2

Main buffering system of the extracellular fluid

Answer 2

Bicarbonate-carbonic acid buffer system

Question 3

Buffering system of the intracellular fluid

Answer 3

Phosphate buffer system

Question 4

Additional H+ in the ICF: equilibrium shifts to the ____

Answer 4

Left

Question 5

Additional OH- in the ICF: equilibrium shifts to the ____

Answer 5

Right

Question 6

Lungs do not remove CO2 at the rate of its production: accumulation of CO2 in the blood (decreased pH); compensation - excretion of H+ and increase reclamation of HCO3

Answer 6

Respiratory acidosis

Question 7

Lungs remove CO2 at a faster rate than its production: decrease in H concentration in the blood (increased pH); compensation - excretion of HCO3 in the urine and reclaim H+ to the blood by the kidneys

Answer 7

Respiratory alkalosis

Question 8

Main site of bicarbonate reclamation

Answer 8

Proximal convoluted tubules

Question 9

Under normal conditions, the kidneys should release ____ of H+ each day

Answer 9

50-100 mmol

Question 10

Accumulation of bicarbonate in the blood (increased blood pH); bicarbonate >26-30 mmol/L; compensation - hypoventilation

Answer 10

Metabolic alkalosis

Question 11

Impaired bicarbonate reabsorption (decreased blood pH); bicarbonate <26-30 mmol/L; compensation: hyperventilation

Answer 11

Metabolic acidosis

Question 12

Possible causes of metabolic alkalosis:

Answer 12

Excretory capability fails (kidney failure)
Lactate, acetate, or bicarbonate IV infusion
Excessive loss of chloride (vomiting, sweating)

Question 13

Possible causes of metabolic acidosis:

Answer 13

Diuretics favoring the excretion of bicarbonate
Excessive loss of cations
Kidney dysfunction (chronic nephritis or infections)
Excessive loss of bicarbonate (diarrhea, drainage from a biliary, pancreatic, or intestinal fistula)

Question 14

Possible causes of respiratory alkalosis:

Answer 14

Hypoxemia
Chemical stimulation by drugs (ie salicylates)
Increase in environmental temperature
Fever, hysteria
Pulmonary emboli, pulmonary fibrosis

Question 15

Possible causes of respiratory acidosis:

Answer 15

COPD, CHD
Hypoventilation caused by drugs (ie barbiturates, alcohol, morphine)
Mechanical obstruction
Asphyxiation

Question 16

Respiratory component in acid-base balance assessment

Answer 16

CO2, dCO2

Question 17

Bicarbonate is proportional to the partial pressure exerted dCO2 while carbonic acid may be derived by multiplying it with the factor ____.

Answer 17

0.0307

Question 18

Directly measured acid-base components

Answer 18

pH and pCO2

Question 19

pO2 uses ____ electrodes for measurement

Answer 19

Clarke

Question 20

pCO2 uses ____ electrodes for measurement

Answer 20

Severinghaus