Acid-Base Determinations (Including Blood Gases) (Chemistry) Flashcards
The expected blood gas results for a patient in chronic renal failure would match the pattern of:
A) metabolic acidosis
B) respiratory acidosis
C) metabolic alkalosis
D) respiratory alkalosis
A) metabolic acidosis
Severe diarrhea causes:
A) metabolic acidosis
B) metabolic alkalosis
C) respiratory acidosis
D) respiratory alkalosis
A) metabolic acidosis
The following blood gas results were obtained:
pH: 7.18
pO2: 86 mm Hg
pCO2: 60 mm Hg
O2 saturation: 92%
HCO3: 21 mEq/L (21 mmol/L)
TCO2: 23 mEq/L (23 mmol/L)
base excess: -8.0 mEq/L (-8.0 mmolL)
The patients results were compatible with which of the following?
A) fever
B) uremia
C) emphysema
D) dehydration
C) emphysema
Factors that contribute to a pCO2 electrode requiring 60-120 seconds to reach equilibrium include the:
A) diffusion characteristics of the membrane
B) actual blood pO2
C) type of calibrating standard (ie, liquid or humidified gas)
D) potential of the polarizing mercury cell
A) diffusion characteristics of the membrane
An emphysema patient suffering from fluid accumulation in the alveolar spaces is likely to be in what metabolic state?
A) respiratory acidosis
B) respiratory alkalosis
C) metabolic acidosis
D) metabolic alkalosis
A) respiratory acidosis
At blood pH 7.40, what is the ratio of bicarbonate to carbonic acid?
A) 15:1
B) 20:1
C) 25:1
D) 30:1
B) 20:1
The reference range for the pH of arterial blood measured at 37 degrees C is:
A) 7.28-7.34
B) 7.33-7.37
C) 7.35-7.45
D) 7.45-7.50
C) 7.35-7.45
A 68 year old man arrives in the emergency room with a glucose level of 722 mg/dL (39.7 mmol/L) and serum acetone of 4+ undiluted. An arterial blood gas from this patient is likely to be:
A) low pH
B) high pH
C) low pO2
D) high pO2
A) low pH
A patient is admitted to the emergency room in a state of metabolic alkalosis. Which of the following would be consistent with this diagnosis?
A) high TCO2, increased HCO3
B) low TCO2, increased HCO3
C) high TCO2, decreased H2CO3
D) low TCO2, decreased H2CO3
A) high TCO2, increased HCO3
A person suspected of having metabolic alkalosis would have which of the following laboratory findings?
A) CO2 content and pCO2 elevated, pH decreased
B) CO2 content decreased and pH elevated
C) CO2 content, pCO2, and pH decreased
D) CO2 content and pH elevated
D) CO2 content and pH elevated
Metabolic acidosis is described as a(n):
A) increase in CO2 content and pCO2 with a decreased pH
B) decrease in CO2 content with an increased pH
C) increase in CO2 content with an increased pH
D) decrease in CO2 content and pCO2 with a decreased pH
D) decrease in CO2 content and pCO2 with a decreased pH
Respiratory acidosis is described as a(n):
A) increase in CO2 content and pCO2 with a decreased pH
B) decrease in CO2 content with an increased pH
C) increase in CO2 content with an increased pH
D) decrease in CO2 content and pCO2 with a decreased pH
A) increase in CO2 content and pCO2 with a decreased pH
A common cause of respiratory alkalosis is:
A) vomiting
B) starvation
C) asthma
D) hyperventilation
D) hyperventilation
Acidosis and alkalosis are best defined as fluctuations in blood pH and CO2 content due to changes in
A) Bohr effect
B) O2 content
C) bicarbonate buffer
D) carbonic anhydrase
C) bicarbonate buffer
A blood gas sample was sent to the lab on ice, and a bubble was present in the syringe. The blood had been exposed to room air for at least 30 minutes. The following change in blood gases will occur:
A) CO2 content increased/pCO2 decreased
B) CO2 content and pO2 increased/pH increased
C) CO2 content and pCO2 decreased/pH decreased
D) pO2 increased/HCO3 decreased
D) pO2 increased/HCO3 decreased
The following laboratory results were obtained:
Serum electrolytes
sodium: 136 mEq/L (136 mmol/L)
potassium: 4.4 mEq/L (4.4 mmol/L)
chloride: 92 mEq/L (92 mmol/L)
bicarbonate: 40 mEq/L (40mmol/L)
Arterial blood
pH: 7.32
pCO2 79 mm Hg
These results are most compatible with:
A) respiratory alkalosis
B) respiratory acidosis
C) metabolic alkalosis
D) metabolic acidosis
B) respiratory acidosis
The most important buffer pair in plasma is the:
A) phosphate/biphosphate pair
B) hemoglobin/imidazole
C) bicarbonate/carbonic acid pair
D) sulfate/bisulfate pair
C) bicarbonate/carbonic acid pair
Most of the carbon dioxide present in blood is in the form of:
A) dissolved CO2
B) carbonate
C) bicarbonate ion
D) carbonic acid
C) bicarbonate ion
In respiratory acidosis, a compensatory mechanism is the increase in:
A) respiration rate
B) ammonia formation
C) blood pCO2
D) plasma bicarbonate concentration
D) plasma bicarbonate concentration
Blood received in the laboratory for blood gas analysis must meet which of the following requirements?
A) on ice, thin fibrin strands only, no air bubbles
B) on ice, no clots, fewer than 4 air bubbles
C) on ice, no clots, no air bubbles
D) room temperature, no clots, no air bubbles
C) on ice, no clots, no air bubbles
Arterial blood that is collected in a heparinized syringe but exposed to room air would be most consistent with the changes in which of the following specimens?
Specimen A
pO2: elevated
pCO2: decreased
pH: elevated
Specimen B
pO2: decreased
pCO2: elevated
pH: decreased
Specimen C
pO2: unchanged
pCO2: elevated
pH: unchanged
Specimen D
pO2: decreased
pCO2: decreased
pH: decreased
A) specimen A
B) specimen B
C) specimen C
D) specimen D
A) specimen A
Specimens for blood gas determination should be drawn into a syringe containing:
A) no preservative
B) heparin
C) EDTA
D) oxalate
B) heparin
Unless blood gas measurements are made immediately after sampling, in vitro glycolysis of the blood causes a:
A) rise in pH and pCO2
B) fall in pH and a rise in pO2
C) rise in pH and a fall in pO2
D) fall in pH and a rise in pCO2
D) fall in pH and a rise in pCO2
An arterial blood specimen submitted for blood gas analysis was obtained at 8:30 am but was not received in the laboratory until 11 am. The technologist should:
A) perform the test immediately upon receipt
B) perform the test only if the specimen was submitted in ice water
C) request a venous blood specimen
D) request a new arterial specimen be obtained
D) request a new arterial specimen be obtained
