Acid-Base Disorders

Question 1

• pH less than 7.35 – 7.45

• Reflects excess acid or H+ concentration

Answer 1

Acidemia

Question 2

• pH greater than 7.35 – 7.45

• Reflects excess base

Answer 2

Alkalemia

Question 3

• Caused by ventilatory dysfunction (a change in pCO2 )

Answer 3

Primary Respiratory Disorder

Question 4

• Resulting from a change in the HCO 3-ion leve

Answer 4

Metabolic (Nonrespiratory) Disorder

Question 5

• The body tries to restore acid-base homeostasis whenever an imbalance occurs

• Body accomplishes this by altering the factor not primarily affected by the pathologic processes

• If the imbalance is of metabolic origin, the body compensates by altering the ventilation

Answer 5

Compensation

Question 6

Compensation

• For disturbances of the RESPIRATORY COMPONENT, the kidneys compensate by…

Answer 6

selectively excreting or reabsorbing anions and cations

Question 7

Compensation

• For disturbances of the RESPIRATORY COMPONENT, the kidneys compensate by selectively excreting or reabsorbing anions and cations

•______ can compensate immediately, but the response is short term and often incomplete

Answer 7

Lungs

Question 8

Compensation

• Kidneys are slower to respond (_____), however, the response is____ term and potentially complete

Answer 8

2-4 days

long

Question 9

• Compensation

________
• Implies that the pH has returned to the normal range (the 20:1 ratio has been restored)

________
• Implies that the pH is approaching normal

Answer 9

Fully Compensated

Partially Compensated

Question 10

• Decrease in bicarbonate, resulting in a decreased pH as a result of the ratio for the nonrespiratory to respiratory component less than____

Answer 10

Primary Metabolic Acidosis

20:1

Question 11

• May be caused by the direct administration of an acidproducing substance

• By excessive formation of organic acids as seen with diabetic ketoacidosis and starvation

Answer 11

Primary Metabolic Acidosis

Question 12

• Reduced excretion of acids (renal tubular acidosis)

• Excessive loss of bicarbonate from diarrhea or drainage from a biliary, pancreatic, or intestinal fistula

Answer 12

Primary Metabolic Acidosis

Question 13

Primary Metabolic Acidosis

• Compensation

• Through______, which is an increase in the rate or depth of breathing

• By “blowing off”____, the base-to-acid ratio will return toward normal

• Secondary compensation occurs when the “original” organ (kidney) begins to correct the ratio by retaining bicarbonate

Answer 13

hyperventilation

CO2

Question 14

Primary Respiratory Acidosis

• Results from a decrease in_______, causing a decreased elimination of CO2 by the lungs

Answer 14

alveolar ventilation (hypoventilation)

Question 15

Primary Respiratory Acidosis

•_______, destructive changes in the airways and alveolar walls increase the size of the alveolar air spaces, with the resultant reduction of the lung surface area available for gas exchange

• As a result, CO2 is retained in the blood, causing chronic_____

•_______, gas exchange is impeded because of the secretions, wbcs, bacteria, and fibrin in the alveoli

Answer 15

COPD

hypercarbia

Bronchopneumonia

Question 16

Primary Respiratory Acidosis

•______ caused by drugs, mechanical obstruction, and asphyxiation, will increase blood pCO2 levels

• Decreased cardiac output (CHF), less blood presented to the lungs for gas exchange, and therefore, an elevated pCO2

Answer 16

Hypoventilation

Question 17

Primary Respiratory Acidosis

• Compensation

• Occurs through nonrespiratory processes

• Kidneys increase the excretion of H+ and increase the reabsorption of HCO3-

• Begins immediately, but it takes days to weeks for maximal compensation to occur

Question 18

Primary Metabolic Alkalosis

• Results from a gain in HCO3-, causing an increase in the nonrespiratory component and increase in the pH

Question 19

Primary Metabolic Alkalosis

• Results from excess administration of _______\ or through ingestion of bicarbonateproducing salts

• Excessive loss of acid
• Vomiting
• Nasogastric suctioning

• Prolong use of diuretics that augment renal excretion of H+

Answer 19

Sodium bicarbonate

Question 20

Primary Metabolic Alkalosis

• Compensation

• Depressing the respiratory center

•_____ increases the retention of carbon dioxide

Answer 20

Hypoventilation

Question 21

• Results from an increased rate of alveolar ventilation causing excessive elimination of carbon dioxide by the lungs

Answer 21

Primary Respiratory Alkalosis

Question 22

• Hypoxemia

• Chemical stimulation of the respiratory center by drugs

• Increase in the environmental temperature

• Hysteria, anxiety (hyperventilation)

• Pulmonary emboli

• Pulmonary fibrosis

Answer 22

Primary Respiratory Alkalosis

Question 23

Primary Respiratory Alkalosis

• Compensation

• Kidneys excrete______ in the urine and reclaiming H+ to the blood

• Popular treatment for hysterical hyperventilation: breathing into a paper bag

Answer 23

HCO3-

Question 24

Specimen Collection for ABG

• Arterial Blood

Answer 24

Heparinized plastic syringe

Glass syringe pretreated with heparin

Heparinized evacuated tubes

Question 25

Blood samples should be chilled with the use of_____ to prevent O2 consumption by the rbc and release of acidic metabolites

Answer 25

ice chips

Question 26

SOURCES OF ERROR
Specimen exposed to air
Specimen at room temperature more than 30 minutes

Answer 26

↓ PCO2; ↑ pH, ↑ PO2

↓ PO2; ↓ pH. ↑ PCO2