NURS 640 EXAM 1 QUESTIONS AND CORRECT ANSWERS 2026

NURS 640 EXAM 1 QUESTIONS AND
CORRECT ANSWERS 2026
SaO2 - CORRECT ANSWERS -95-100%



PaO2 - CORRECT ANSWERS -80-100



PAO2 - CORRECT ANSWERS -60-100



A-a gradient - CORRECT ANSWERS -PAO2-PaO2



PaO2/FiO2 ratio - CORRECT ANSWERS ->300



ABG format - CORRECT ANSWERS -pH/PaCO2/PaO2/HCO3/SaO2



Arterial sampling - CORRECT ANSWERS -pH: 7.35-7.45

PaCO2: 35-45

PaO2: 80-100

HCO3: 22-26

SaO2: 95



Venous sampling - CORRECT ANSWERS -pH: 7.31-7.41

PaCO2: 41-51

PaO2: 35-40

HCO3: 22-26

SaO2: 70-75

, Hypoxemia grading scale - CORRECT ANSWERS -None: PaO2 >80 SpO2 >95

Mild: PaO2 60-79 SpO2 90-94

Moderate: PaO2 40-59 SpO2 75-89

Severe: PaO2 <40 SpO2<75



Pulse Oximetry Indications - CORRECT ANSWERS -•Written as SpO2

•Non-invasive monitoring used in situations where when hypoxemia can occur

•Represents the amount of oxygen bound to functional hemoglobin

•Used as surrogate to estimate PaO2 non-invasively, however limitations to pulse oximetry
impact pulse oximetry accuracy

•When ischemia / severe anemia occurs, it does not accurately represent oxygen delivery to
tissues



Pulse Oximetry limitations - CORRECT ANSWERS -• SpO2 < 80%

• Movement

• Bright light interference

• Intravascular interference (ex: dye)

• Extravascular interference (ex: polish)

• Non-functional hemoglobin

• Reduced blood flow

Hyperoxemia cannot be detected



Respiratory acidosis - CORRECT ANSWERS -• CNS depression

• Sedation

• Chest wall injury

• Respiratory obstruction