NR 341 Quiz #1 ABGs | QUESTIONS AND ANSWERS
Why is an ABG analysis usually ordered? An ABG analysis is usually one of the first tests ordered to assess respiratory status
because it helps evaluate gas exchange in the lungs.
What measures are included in an ABG analysis? -pH
-Partial pressure of arterial carbon dioxide
-Partial pressure of arterial oxygen
-Bicarbonate level
What does pH show in an ABG analysis? pH is an indication of hydrogen ion concentration in the blood and shows the
blood's alkalinity or acidity.
What does the partial pressure of arterial carbon dioxide Known as the respiratory parameter, PaCO2 reflects the adequacy of the lungs'
reflect in an ABG analysis? ventilation and CO2 elimination.
What does the partial pressure of arterial oxygen reflect The PaO2 reflects the body's ability to pick up O2 from the lungs
in an ABG analysis?
What does thee bicarbonate level reflect in an ABG Known as the metabolic parameter, the HCO3- level reflects the kidney's ability to
analysis? retain and excrete HCO3-
What are the normal ABG values? -pH: 7.35-7.45
-PaCO2: 35-45 mmHg
-HCO3-: 22-26 mEq/L
-PaO2: 80-100 mmHg
What lab levels characterize respiratory acidosis? pH < 7.35; PaCO2 > 45
, What causes respiratory acidosis? Hypoventilation (CNS depression, pulmonary edema)
Chronic obstructive pulmonary disease (COPD), sedative overdose, severe
pneumonia, atelectasis, respiratory muscle weakness
What are the assessment findings that accompany Bradycardia, hypotension, confusion
respiratory acidosis? Lethargy, dizziness, headache, coma, warm/flushed skin, seizures, dysrhythmias
(related to potassium shifts during compensation)
What are the treatments for respiratory acidosis? Increase RR, reposition patient, maintain patent airway
What lab values characterize respiratory alkalosis? pH > 7.45; PaCO2 < 35
What causes respiratory alkalosis? Hyperventilation (excessive mechanical ventilation, anxiety, fever, pneumothorax)
Hypoxemia from acute pulmonary disorders
What assessment findings accompany respiratory Tachycardia, palpitations, anxiety, seizures, perspiration/diaphoresis
alkalosis? Dizziness, lightheadedness, confusion, headache, tachycardia, dysrhythmias
(related to potassium shifts during compensation), nausea, vomiting, diarrhea,
tetany, numbness, tingling, hyperreflexia
What are the treatments for respiratory alkalosis? Decrease RR, administer sedatives, rebreather mask
Mechanical ventilation (dec. RR, sedation, dec. Vt.)
What lab values characterize metabolic acidosis? pH > 7.45; HCO3 < 22
What causes metabolic acidosis? Acid gain (shock, diabetic ketoacidosis, renal failure, lactic acidosis)
Bicarbonate loss (diarrhea, bile drainage, GI fistulas)
What assessment findings accompany metabolic N/V, malaise, tachypnea, hypotension, confusion
acidosis? Lethargy, dizziness, headache, coma, dysrhythmias (related to potassium
shifts during compensation), cold/clammy skin, muscle weakness
What are the treatments for metabolic acidosis? Improve oxygenation, treat cause (DKA, diarrhea, renal failure)
What lab values accompany metabolic alkalosis? pH > 7.45; HCO3 > 26
What causes metabolic alkalosis? Acid loss (vomiting, gastric suctioning, potassium loss via diuretic use,
hyperaldosteronism caused by Cushing's, steroids, or bicarbonate)
Gain in HCO3 (ingestion)
What assessment findings accompany metabolic N/V/D, confusion, seizures, tetany
alkalosis? Irritability, lethargy, headache, tachycardia, dysrhythmias (related to potassium
shifts during compensation), anorexia, tremors, tingling of fingers and toes,
muscles cramps
What are the treatments for metabolic alkalosis? Administer buffer, treat cause
Where should an ABG analysis be drawn from? Should be drawn from an arterial line if the patient has one. If no arterial line, the
brachial, radial, or femoral arteries can be used.
Why is an ABG analysis usually ordered? An ABG analysis is usually one of the first tests ordered to assess respiratory status
because it helps evaluate gas exchange in the lungs.
What measures are included in an ABG analysis? -pH
-Partial pressure of arterial carbon dioxide
-Partial pressure of arterial oxygen
-Bicarbonate level
What does pH show in an ABG analysis? pH is an indication of hydrogen ion concentration in the blood and shows the
blood's alkalinity or acidity.
What does the partial pressure of arterial carbon dioxide Known as the respiratory parameter, PaCO2 reflects the adequacy of the lungs'
reflect in an ABG analysis? ventilation and CO2 elimination.
What does the partial pressure of arterial oxygen reflect The PaO2 reflects the body's ability to pick up O2 from the lungs
in an ABG analysis?
What does thee bicarbonate level reflect in an ABG Known as the metabolic parameter, the HCO3- level reflects the kidney's ability to
analysis? retain and excrete HCO3-
What are the normal ABG values? -pH: 7.35-7.45
-PaCO2: 35-45 mmHg
-HCO3-: 22-26 mEq/L
-PaO2: 80-100 mmHg
What lab levels characterize respiratory acidosis? pH < 7.35; PaCO2 > 45
, What causes respiratory acidosis? Hypoventilation (CNS depression, pulmonary edema)
Chronic obstructive pulmonary disease (COPD), sedative overdose, severe
pneumonia, atelectasis, respiratory muscle weakness
What are the assessment findings that accompany Bradycardia, hypotension, confusion
respiratory acidosis? Lethargy, dizziness, headache, coma, warm/flushed skin, seizures, dysrhythmias
(related to potassium shifts during compensation)
What are the treatments for respiratory acidosis? Increase RR, reposition patient, maintain patent airway
What lab values characterize respiratory alkalosis? pH > 7.45; PaCO2 < 35
What causes respiratory alkalosis? Hyperventilation (excessive mechanical ventilation, anxiety, fever, pneumothorax)
Hypoxemia from acute pulmonary disorders
What assessment findings accompany respiratory Tachycardia, palpitations, anxiety, seizures, perspiration/diaphoresis
alkalosis? Dizziness, lightheadedness, confusion, headache, tachycardia, dysrhythmias
(related to potassium shifts during compensation), nausea, vomiting, diarrhea,
tetany, numbness, tingling, hyperreflexia
What are the treatments for respiratory alkalosis? Decrease RR, administer sedatives, rebreather mask
Mechanical ventilation (dec. RR, sedation, dec. Vt.)
What lab values characterize metabolic acidosis? pH > 7.45; HCO3 < 22
What causes metabolic acidosis? Acid gain (shock, diabetic ketoacidosis, renal failure, lactic acidosis)
Bicarbonate loss (diarrhea, bile drainage, GI fistulas)
What assessment findings accompany metabolic N/V, malaise, tachypnea, hypotension, confusion
acidosis? Lethargy, dizziness, headache, coma, dysrhythmias (related to potassium
shifts during compensation), cold/clammy skin, muscle weakness
What are the treatments for metabolic acidosis? Improve oxygenation, treat cause (DKA, diarrhea, renal failure)
What lab values accompany metabolic alkalosis? pH > 7.45; HCO3 > 26
What causes metabolic alkalosis? Acid loss (vomiting, gastric suctioning, potassium loss via diuretic use,
hyperaldosteronism caused by Cushing's, steroids, or bicarbonate)
Gain in HCO3 (ingestion)
What assessment findings accompany metabolic N/V/D, confusion, seizures, tetany
alkalosis? Irritability, lethargy, headache, tachycardia, dysrhythmias (related to potassium
shifts during compensation), anorexia, tremors, tingling of fingers and toes,
muscles cramps
What are the treatments for metabolic alkalosis? Administer buffer, treat cause
Where should an ABG analysis be drawn from? Should be drawn from an arterial line if the patient has one. If no arterial line, the
brachial, radial, or femoral arteries can be used.
