NUR 445 Exam 2 COMPLETE EXAM QUESTIONS WITH
DETAILED VERIFIED ANSWERS (100% CORRECT ANSWERS)
ALREADY GRADED A+
What is the definition of affinity? - ANSWER the attraction between Hgb
and O2
What does Hgb have an affinity to? - ANSWER Hgb has an attraction for
O2 molecules
What does the oxyhemoglobin dissociation curve represent? - ANSWER
relationship between PaO2 and SaO2
What is PaO2? - ANSWER partial pressure of arterial O2 (arterial O2
tension)
What is SaO2? - ANSWER Hgb saturation
What does P50 represent? - ANSWER measures when Hgb is 50%
saturated with O2
When does the P50 change? - ANSWER when physiologic factors are
altered
,What does a left shift on the dissociation curve do to the affinity of O2
to hemoglobin? - ANSWER increases affinity = prevents release to tissues
What does a right shift on the dissociation curve do to the affinity of O2
to hemoglobin? - ANSWER decreases affinity = readily release to tissues
What causes a left shift on the dissociation curve? - ANSWER alkalosis,
hypothermia, hypocapnia, decreased 2,3 DPG
What causes a right shift on the dissociation curve? - ANSWER acidosis,
hyperthermia, hypercapnia, increased 2,3-DPG
What are three components of oxygenation? - ANSWER pulmonary gas
exchange, O2 delivery, O2 consumption
What 2 problems in oxygenation does the nurse assess for and
intervene? - ANSWER decreased O2 supply, increased O2 demand
What is the definition of oxygenation? - ANSWER the use of O2 for
energy through aerobic metabolism
What are the two goals in the assessment of oxygenation? - ANSWER to
determine the overall adequacy of oxygenation and to determine which
component of oxygenation dysfunction should be manipulated
,What are the three components of pulmonary gas exchange? - ANSWER
ventilation, diffusion, perfusion
What is the definition of ventilation? - ANSWER movement of air
between the atmosphere and the lungs
What is the actual work of breathing called (using the muscles, lungs,
airway, nervous system)? - ANSWER ventilation
What is the definition of diffusion? - ANSWER movement of gas across
pressure gradient from area of high concentration to low concentration
What is it called when O2 moves from alveoli to pulmonary capillaries? -
ANSWER diffusion
What is the definition of perfusion? - ANSWER pulmonary perfusion of
pulmonary capillaries; flow of blood to tissues/organs
What is perfusion affected by? - ANSWER Hgb, O2 affinity, and blood
flow
Why is the matching of ventilation to perfusion essential for gas
exchange? - ANSWER when they are not matched, oxygen becomes
impaired
, When might ventilation to perfusion mismatching occur? - ANSWER PE,
pneumothorax, hypoxemia
What are the components of oxygen delivery? - ANSWER CO, CaO2, ANS
innervation, auto-regulation
What is afterload? - ANSWER resistance ventricle pumps blood
What is the normal value for afterload? - ANSWER 800-1200
What is cardiac output? - ANSWER amount of blood pumped each
minute
What is the normal value for cardiac output? - ANSWER 4-8
What is CaO2? - ANSWER Total O2 carried in arterial blood
What is combined SaO2 and PaO2? - ANSWER CaO2
What is contractility? - ANSWER the force of contractions
What is DO2? - ANSWER process of O2 transport to cells, utilizing CO,
CaO2, autoregulation, and ANS innervation
DETAILED VERIFIED ANSWERS (100% CORRECT ANSWERS)
ALREADY GRADED A+
What is the definition of affinity? - ANSWER the attraction between Hgb
and O2
What does Hgb have an affinity to? - ANSWER Hgb has an attraction for
O2 molecules
What does the oxyhemoglobin dissociation curve represent? - ANSWER
relationship between PaO2 and SaO2
What is PaO2? - ANSWER partial pressure of arterial O2 (arterial O2
tension)
What is SaO2? - ANSWER Hgb saturation
What does P50 represent? - ANSWER measures when Hgb is 50%
saturated with O2
When does the P50 change? - ANSWER when physiologic factors are
altered
,What does a left shift on the dissociation curve do to the affinity of O2
to hemoglobin? - ANSWER increases affinity = prevents release to tissues
What does a right shift on the dissociation curve do to the affinity of O2
to hemoglobin? - ANSWER decreases affinity = readily release to tissues
What causes a left shift on the dissociation curve? - ANSWER alkalosis,
hypothermia, hypocapnia, decreased 2,3 DPG
What causes a right shift on the dissociation curve? - ANSWER acidosis,
hyperthermia, hypercapnia, increased 2,3-DPG
What are three components of oxygenation? - ANSWER pulmonary gas
exchange, O2 delivery, O2 consumption
What 2 problems in oxygenation does the nurse assess for and
intervene? - ANSWER decreased O2 supply, increased O2 demand
What is the definition of oxygenation? - ANSWER the use of O2 for
energy through aerobic metabolism
What are the two goals in the assessment of oxygenation? - ANSWER to
determine the overall adequacy of oxygenation and to determine which
component of oxygenation dysfunction should be manipulated
,What are the three components of pulmonary gas exchange? - ANSWER
ventilation, diffusion, perfusion
What is the definition of ventilation? - ANSWER movement of air
between the atmosphere and the lungs
What is the actual work of breathing called (using the muscles, lungs,
airway, nervous system)? - ANSWER ventilation
What is the definition of diffusion? - ANSWER movement of gas across
pressure gradient from area of high concentration to low concentration
What is it called when O2 moves from alveoli to pulmonary capillaries? -
ANSWER diffusion
What is the definition of perfusion? - ANSWER pulmonary perfusion of
pulmonary capillaries; flow of blood to tissues/organs
What is perfusion affected by? - ANSWER Hgb, O2 affinity, and blood
flow
Why is the matching of ventilation to perfusion essential for gas
exchange? - ANSWER when they are not matched, oxygen becomes
impaired
, When might ventilation to perfusion mismatching occur? - ANSWER PE,
pneumothorax, hypoxemia
What are the components of oxygen delivery? - ANSWER CO, CaO2, ANS
innervation, auto-regulation
What is afterload? - ANSWER resistance ventricle pumps blood
What is the normal value for afterload? - ANSWER 800-1200
What is cardiac output? - ANSWER amount of blood pumped each
minute
What is the normal value for cardiac output? - ANSWER 4-8
What is CaO2? - ANSWER Total O2 carried in arterial blood
What is combined SaO2 and PaO2? - ANSWER CaO2
What is contractility? - ANSWER the force of contractions
What is DO2? - ANSWER process of O2 transport to cells, utilizing CO,
CaO2, autoregulation, and ANS innervation
