NUR 445 Exam 2 COMPLETE EXAM
QUESTIONS WITH DETAILED
VERIFIED ANSWERS (100%
CORRECT ANSWERS) ALREADY
GRADED A+
What is the definition of affinity? - Ans--the attraction between Hgb and O2
What does Hgb have an affinity to? - Ans--Hgb has an attraction for O2
molecules
What does the oxyhemoglobin dissociation curve represent? - Ans--
relationship between PaO2 and SaO2
What is PaO2? - Ans--partial pressure of arterial O2 (arterial O2 tension)
What is SaO2? - Ans--Hgb saturation
What does P50 represent? - Ans--measures when Hgb is 50% saturated
with O2
When does the P50 change? - Ans--when physiologic factors are altered
What does a left shift on the dissociation curve do to the affinity of O2 to
hemoglobin? - Ans--increases affinity = prevents release to tissues
What does a right shift on the dissociation curve do to the affinity of O2 to
hemoglobin? - Ans--decreases affinity = readily release to tissues
What causes a left shift on the dissociation curve? - Ans--alkalosis,
hypothermia, hypocapnia, decreased 2,3 DPG
What causes a right shift on the dissociation curve? - Ans--acidosis,
hyperthermia, hypercapnia, increased 2,3-DPG
,What are three components of oxygenation? - Ans--pulmonary gas
exchange, O2 delivery, O2 consumption
What 2 problems in oxygenation does the nurse assess for and intervene? -
Ans--decreased O2 supply, increased O2 demand
What is the definition of oxygenation? - Ans--the use of O2 for energy
through aerobic metabolism
What are the two goals in the assessment of oxygenation? - Ans--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? - Ans--
ventilation, diffusion, perfusion
What is the definition of ventilation? - Ans--movement of air between the
atmosphere and the lungs
What is the actual work of breathing called (using the muscles, lungs,
airway, nervous system)? - Ans--ventilation
What is the definition of diffusion? - Ans--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? -
Ans--diffusion
What is the definition of perfusion? - Ans--pulmonary perfusion of
pulmonary capillaries; flow of blood to tissues/organs
What is perfusion affected by? - Ans--Hgb, O2 affinity, and blood flow
Why is the matching of ventilation to perfusion essential for gas exchange?
- Ans--when they are not matched, oxygen becomes impaired
,When might ventilation to perfusion mismatching occur? - Ans--PE,
pneumothorax, hypoxemia
What are the components of oxygen delivery? - Ans--CO, CaO2, ANS
innervation, auto-regulation
What is afterload? - Ans--resistance ventricle pumps blood
What is the normal value for afterload? - Ans--800-1200
What is cardiac output? - Ans--amount of blood pumped each minute
What is the normal value for cardiac output? - Ans--4-8
What is CaO2? - Ans--Total O2 carried in arterial blood
What is combined SaO2 and PaO2? - Ans--CaO2
What is contractility? - Ans--the force of contractions
What is DO2? - Ans--process of O2 transport to cells, utilizing CO, CaO2,
autoregulation, and ANS innervation
What is the product of CO and CaO2? - Ans--DO2
What is HgbO2? - Ans--hemoglobin fully saturated with O2
What is SaO2/SpO2? - Ans--ratio of HgbO2 to total Hgb
What is the difference between SaO2 and SpO2? - Ans--SpO2 means
obtained through pulse oximetry, where SaO2 is via arterial blood
What is stroke volume? - Ans--volume pumped with each beat
What is the normal value of stroke volume? - Ans--50-100
What is the normal value of Hgb? - Ans--12-17
, What does PaO2 represent? - Ans--amount of oxygen dissolved in plasma
What does SaO2 represent? - Ans--Saturation of Hgb with O2
(oxyhemoglobin)
What is the percentage of the body's oxygen on HgbO2 (SaO2)? - Ans--
97%
What percentage of the body's oxygen is dissolved in plasma (PaO2)? -
Ans--3%
What can impair O2 delivery? - Ans--dysrhythmias, heart failure,
uncompensated decrease in CO, Hgb, or SaO2
How is O2 delivery assessed? - Ans--CO, Hgb, SaO2, PaO2 (ABGs)
How can CO be assessed at the bedside? - Ans--pulses, heart sounds,
monitor, fluid balance, CVP, heart sounds, O2 status, BP, pulse pressure,
Hx of previous MI, acute MI or ischemia
What is the definition of oxygen consumption? - Ans--the rate at which O2 is
used by cells to generate energy
What is the definition of aerobic metabolism? - Ans--carbs/fats/proteins
broken down into ATP (through Krebs cycle); creates intracellular energy
stores to release when energy is required
What is the definition of anaerobic metabolism? - Ans--backup mechanism
to generate energy in the absence of O2; this occurs through the
metabolism of carbs, the only food that can generate ATP without oxygen
What are byproducts of anaerobic metabolism? - Ans--pyruvate and
lactate
What can a patient develop if anaerobic metabolism persists? - Ans--
ischemic stroke, cardiac arrest, lactic acidosis
What is oxygen extraction? - Ans--when cells take O2 from the blood
QUESTIONS WITH DETAILED
VERIFIED ANSWERS (100%
CORRECT ANSWERS) ALREADY
GRADED A+
What is the definition of affinity? - Ans--the attraction between Hgb and O2
What does Hgb have an affinity to? - Ans--Hgb has an attraction for O2
molecules
What does the oxyhemoglobin dissociation curve represent? - Ans--
relationship between PaO2 and SaO2
What is PaO2? - Ans--partial pressure of arterial O2 (arterial O2 tension)
What is SaO2? - Ans--Hgb saturation
What does P50 represent? - Ans--measures when Hgb is 50% saturated
with O2
When does the P50 change? - Ans--when physiologic factors are altered
What does a left shift on the dissociation curve do to the affinity of O2 to
hemoglobin? - Ans--increases affinity = prevents release to tissues
What does a right shift on the dissociation curve do to the affinity of O2 to
hemoglobin? - Ans--decreases affinity = readily release to tissues
What causes a left shift on the dissociation curve? - Ans--alkalosis,
hypothermia, hypocapnia, decreased 2,3 DPG
What causes a right shift on the dissociation curve? - Ans--acidosis,
hyperthermia, hypercapnia, increased 2,3-DPG
,What are three components of oxygenation? - Ans--pulmonary gas
exchange, O2 delivery, O2 consumption
What 2 problems in oxygenation does the nurse assess for and intervene? -
Ans--decreased O2 supply, increased O2 demand
What is the definition of oxygenation? - Ans--the use of O2 for energy
through aerobic metabolism
What are the two goals in the assessment of oxygenation? - Ans--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? - Ans--
ventilation, diffusion, perfusion
What is the definition of ventilation? - Ans--movement of air between the
atmosphere and the lungs
What is the actual work of breathing called (using the muscles, lungs,
airway, nervous system)? - Ans--ventilation
What is the definition of diffusion? - Ans--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? -
Ans--diffusion
What is the definition of perfusion? - Ans--pulmonary perfusion of
pulmonary capillaries; flow of blood to tissues/organs
What is perfusion affected by? - Ans--Hgb, O2 affinity, and blood flow
Why is the matching of ventilation to perfusion essential for gas exchange?
- Ans--when they are not matched, oxygen becomes impaired
,When might ventilation to perfusion mismatching occur? - Ans--PE,
pneumothorax, hypoxemia
What are the components of oxygen delivery? - Ans--CO, CaO2, ANS
innervation, auto-regulation
What is afterload? - Ans--resistance ventricle pumps blood
What is the normal value for afterload? - Ans--800-1200
What is cardiac output? - Ans--amount of blood pumped each minute
What is the normal value for cardiac output? - Ans--4-8
What is CaO2? - Ans--Total O2 carried in arterial blood
What is combined SaO2 and PaO2? - Ans--CaO2
What is contractility? - Ans--the force of contractions
What is DO2? - Ans--process of O2 transport to cells, utilizing CO, CaO2,
autoregulation, and ANS innervation
What is the product of CO and CaO2? - Ans--DO2
What is HgbO2? - Ans--hemoglobin fully saturated with O2
What is SaO2/SpO2? - Ans--ratio of HgbO2 to total Hgb
What is the difference between SaO2 and SpO2? - Ans--SpO2 means
obtained through pulse oximetry, where SaO2 is via arterial blood
What is stroke volume? - Ans--volume pumped with each beat
What is the normal value of stroke volume? - Ans--50-100
What is the normal value of Hgb? - Ans--12-17
, What does PaO2 represent? - Ans--amount of oxygen dissolved in plasma
What does SaO2 represent? - Ans--Saturation of Hgb with O2
(oxyhemoglobin)
What is the percentage of the body's oxygen on HgbO2 (SaO2)? - Ans--
97%
What percentage of the body's oxygen is dissolved in plasma (PaO2)? -
Ans--3%
What can impair O2 delivery? - Ans--dysrhythmias, heart failure,
uncompensated decrease in CO, Hgb, or SaO2
How is O2 delivery assessed? - Ans--CO, Hgb, SaO2, PaO2 (ABGs)
How can CO be assessed at the bedside? - Ans--pulses, heart sounds,
monitor, fluid balance, CVP, heart sounds, O2 status, BP, pulse pressure,
Hx of previous MI, acute MI or ischemia
What is the definition of oxygen consumption? - Ans--the rate at which O2 is
used by cells to generate energy
What is the definition of aerobic metabolism? - Ans--carbs/fats/proteins
broken down into ATP (through Krebs cycle); creates intracellular energy
stores to release when energy is required
What is the definition of anaerobic metabolism? - Ans--backup mechanism
to generate energy in the absence of O2; this occurs through the
metabolism of carbs, the only food that can generate ATP without oxygen
What are byproducts of anaerobic metabolism? - Ans--pyruvate and
lactate
What can a patient develop if anaerobic metabolism persists? - Ans--
ischemic stroke, cardiac arrest, lactic acidosis
What is oxygen extraction? - Ans--when cells take O2 from the blood
