Advanced Respiratory Volumes and Capacities Quiz

1. What are 3 lung volumes that can't be measured by spirometry?

VC(Vital Capacity), IC(Inspiratory Capacity), IRV(Inspiratory Reserve Volume)

VC, IC, and IRV can be measured by spirometry, unlike RV, FRC, and TLC which can't be measured due to the limitations of the test.

Explanation

VC, IC, and IRV can be measured by spirometry, unlike RV, FRC, and TLC which can't be measured due to the limitations of the test.

2. How are IRV (Inspiratory reserve volume) and TV (Tidal volume) related?

B. TV is the amount of air that remains in the lungs after forced exhalation.

C. IRV and TV are completely unrelated and do not affect each other.

A. IRV is the maximum amount of air that can be exhaled after the Tidal volume has been exhaled.

Inspiratory Reserve Volume (IRV) is the additional air that can be inhaled after a normal inhalation of Tidal Volume (TV). Inspiratory Capacity is calculated as the sum of TV and IRV. Therefore, the correct relationship between IRV and TV is that IRV represents the additional air that can be inhaled on top of the Tidal Volume.

Explanation

Inspiratory Reserve Volume (IRV) is the additional air that can be inhaled after a normal inhalation of Tidal Volume (TV). Inspiratory Capacity is calculated as the sum of TV and IRV. Therefore, the correct relationship between IRV and TV is that IRV represents the additional air that can be inhaled on top of the Tidal Volume.

3. What is the association between ERV and RV in relation to Functional Residual Capacity (FRC)?

ERV/RV=FRC

ERV x RV = FRC

ERV-RV=FRC

The correct association between ERV and RV to determine FRC is by adding ERV and RV together, not subtracting, multiplying, or dividing them.

Explanation

The correct association between ERV and RV to determine FRC is by adding ERV and RV together, not subtracting, multiplying, or dividing them.

4. What is the difference between IRV and IC in relation to breathing?

IRV (Inspiratory Reserve Volume) and IC (Inspiratory Capacity) are both respiratory measurements, but IRV specifically pertains to the additional air that can be inhaled after a normal breath in, while IC represents the total amount of air that can be inhaled after a normal exhale. Understanding the distinctions between these terms is essential in respiratory physiology.

Explanation

IRV (Inspiratory Reserve Volume) and IC (Inspiratory Capacity) are both respiratory measurements, but IRV specifically pertains to the additional air that can be inhaled after a normal breath in, while IC represents the total amount of air that can be inhaled after a normal exhale. Understanding the distinctions between these terms is essential in respiratory physiology.

5. What is the difference between ERV and Vital Capacity?

ERV is the amount of air that can be blown out after normal expiration, and it is part of the Vital Capacity along with TV and IRV. Understanding this distinction is crucial in respiratory physiology.

Explanation

ERV is the amount of air that can be blown out after normal expiration, and it is part of the Vital Capacity along with TV and IRV. Understanding this distinction is crucial in respiratory physiology.

6. Why is the apex of the healthy lung the largest contributor of alveolar dead space and how can this explain why physiologic dead space increases with V/Q mismatch (such as in PE)?

In V/Q mismatch conditions like PE, an increase in ventilation leads to a decrease in physiologic dead space.

Physiologic dead space is mainly determined by the volume of air in the lower lobes of the lungs.

The apex of the healthy lung has the highest blood supply which contributes to the majority of gas exchange.

The correct answer explains that the apices of the lungs are less perfused and have higher oxygenation, leading to less gas exchange and contributing to dead space. In V/Q mismatch like in PE, a decrease in perfusion results in increased dead space rather than improved gas exchange.

Explanation

The correct answer explains that the apices of the lungs are less perfused and have higher oxygenation, leading to less gas exchange and contributing to dead space. In V/Q mismatch like in PE, a decrease in perfusion results in increased dead space rather than improved gas exchange.

7. How can you calculate Physiologic dead space?

Vd=Vt times (PaCO2-PECO2)

Vd=Vt times (PECO2/ PaCO2)

Vd=Vt times (PaCO2/PECO2/PaCO2)

Physiologic dead space calculation involves understanding the concept of gas exchange and using the formula mentioned in the correct answer to determine the amount of inspired air that does not participate in gas exchange.

Explanation

Physiologic dead space calculation involves understanding the concept of gas exchange and using the formula mentioned in the correct answer to determine the amount of inspired air that does not participate in gas exchange.

8. What are the key concepts to understand the difference between Alveolar and minute ventilation?

Minute ventilation and Alveolar ventilation are crucial concepts in understanding respiratory physiology. Minute ventilation focuses on the total volume of air entering the lungs per minute, while Alveolar ventilation specifically measures the volume of air participating in gas exchange. Understanding how to calculate both types of ventilation is important for evaluating respiratory function.

Explanation

Minute ventilation and Alveolar ventilation are crucial concepts in understanding respiratory physiology. Minute ventilation focuses on the total volume of air entering the lungs per minute, while Alveolar ventilation specifically measures the volume of air participating in gas exchange. Understanding how to calculate both types of ventilation is important for evaluating respiratory function.

9. What determines combined volumes of Lung and chest wall?

The number of cells in the Lung and chest wall.

The temperature of the Lung and chest wall.

The color of the Lung and chest wall.

The combined volumes of Lungs and chest wall are determined by the elastic properties of both structures. Elastic recoil plays a key role in maintaining the normal physiology of the respiratory system.

Explanation

The combined volumes of Lungs and chest wall are determined by the elastic properties of both structures. Elastic recoil plays a key role in maintaining the normal physiology of the respiratory system.

10. What does the High deltaV/deltaP ratio tell you about stiffness and compliance? How do compliance and this ratio change in Normal aging, Emphysema, Pneumonia, Pulmonary edema, NRDS, and Pulmonary Fibrosis? How does surfactant affect this ratio?

Surfactant decreases compliance and increases the deltaV/deltaP ratio.

Compliance decreases with Normal aging and Emphysema.

Pneumonia and Pulmonary Edema increase the Compliance and the deltaV/deltaP ratio.

11. Increased temperature, CO2, H+, and 2,3 BPG all favor the formation of the Taut form of hemoglobin. What does that mean?

The Taut form of hemoglobin has higher affinity for O2, resulting in increased oxygenation of tissues.

Understanding how different factors affect the affinity of hemoglobin for oxygen is crucial for comprehending the oxygen dissociation curve and its shifts.

Explanation

Understanding how different factors affect the affinity of hemoglobin for oxygen is crucial for comprehending the oxygen dissociation curve and its shifts.

12. Exposure to Gas Exhaust, Fires, Gas Heaters...FIRST symptom? SaO2 on Co-oximeter vs Pulse Oximeter...Shift of Oxygen Binding curve, why?

Increased O2 availability for unloading into tissues due to CO poisoning

CO poisoning results in increased SaO2 on Pulse oximeter

Symptom is usually nausea and vomiting

13. Why might alkalosis result in erythrocytosis?

Because alkalosis results in increased O2 unloading to tissues, reducing the need for erythrocyte production.

Because alkalosis causes a decrease in EPO production, leading to a decrease in erythrocyte synthesis.

Because during alkalosis, there is an increase in pH which directly stimulates erythrocyte production.

Alkalosis leads to a decrease in pH which shifts the OBC curve to the left, resulting in less O2 unloading to tissues and ultimately causing renal hypoxia and an increase in EPO production, leading to erythrocytosis.

Explanation

Alkalosis leads to a decrease in pH which shifts the OBC curve to the left, resulting in less O2 unloading to tissues and ultimately causing renal hypoxia and an increase in EPO production, leading to erythrocytosis.

14. Hemoglobin is a tetramer (2 alpha and 2 beta) and exhibits cooperativity, resulting in a sigmoid shape on the oxygen-hemoglobin dissociation curve. Will it have a higher affinity for O2 when compared to Myoglobin?

Yes, Myoglobin will have a higher affinity for O2 compared to Hemoglobin.

No, Hemoglobin will have a lower affinity for O2 compared to Myoglobin.

No, Hemoglobin will have the same affinity for O2 as Myoglobin.

Cooperativity in Hemoglobin leads to a sigmoid shape on the oxygen-hemoglobin dissociation curve, indicating higher O2 affinity than Myoglobin which lacks multiple binding sites for positive cooperativity.

Explanation

Cooperativity in Hemoglobin leads to a sigmoid shape on the oxygen-hemoglobin dissociation curve, indicating higher O2 affinity than Myoglobin which lacks multiple binding sites for positive cooperativity.

15. Calculate the amount of O2 delivered to tissues given a cardiac output of 5.25, arterial O2 saturation (SaO2), partial pressure of O2 (PaO2), and hemoglobin level.

O2 content = Hb x SaO2

O2 delivery to tissues = SaO2 - PaO2

Hemoglobin concentration does not affect O2 delivery to tissues

The calculation for O2 content and delivery to tissues involves multiple factors including O2 binding capacity, percent saturation, dissolved O2, and hemoglobin level. Hemoglobin concentration plays a crucial role in determining the amount of O2 delivered to tissues.

Explanation

The calculation for O2 content and delivery to tissues involves multiple factors including O2 binding capacity, percent saturation, dissolved O2, and hemoglobin level. Hemoglobin concentration plays a crucial role in determining the amount of O2 delivered to tissues.

16. Why is the Total O2 content of Blood decreased in cases of CO poisoning or Methemoglobinemia even though Hemoglobin concentration and PaO2 are normal?

The decrease in Total O2 content is due to a decrease in Hemoglobin concentration caused by CO poisoning or Methemoglobinemia.

In cases of CO poisoning or Methemoglobinemia, the decrease in Total O2 content is primarily due to a decrease in the % of O2 saturation of Hemoglobin (SaO2) caused by the inability of Fe3+ to bind O2 effectively or the occupation of O2 binding sites by CO.

Explanation

In cases of CO poisoning or Methemoglobinemia, the decrease in Total O2 content is primarily due to a decrease in the % of O2 saturation of Hemoglobin (SaO2) caused by the inability of Fe3+ to bind O2 effectively or the occupation of O2 binding sites by CO.

17. Why are lungs unique in their response to hypoxia and what is the significance in pathology?

Alveolar O2 decreases which causes vasodilation in areas with high O2.

Decreased alveolar O2 levels lead to decreased blood flow to the lungs causing decreased resistance in the pulmonary arteries.

Because they need to take oxygen from the blood, not oxygenate it.

18. Emphysema vs Fibrosis: Diffusion/Perfusion limited? Why?

Emphysema and Fibrosis both result in a perfusion limited state.

Emphysema results in a perfusion limited state, while Fibrosis results in a diffusion limited state.

Emphysema and Fibrosis both result in a problem related to oxygen transportation.

19. Calculate Pulmonary Vascular Resistance if you know Pulmonary Capillary Wedge Pressure, Pulmonary artery pressure and Cardiac output.

Pulmonary Vascular Resistance is calculated by subtracting Pulmonary Capillary Wedge Pressure from Pulmonary Artery Pressure.

Pulmonary Vascular Resistance is the same as Pulmonary Artery Pressure.

Cardiac Output is not relevant in calculating Pulmonary Vascular Resistance.

To calculate Pulmonary Vascular Resistance, it is the difference between the Pressure in Pulmonary artery and the Pressure in the LEFT atrium divided by Cardiac Output. This formula is a result of the formula: Resistance(R)=Pressure(P)/Flow(Q), where you can manipulate it to solve for different variables.

Explanation

To calculate Pulmonary Vascular Resistance, it is the difference between the Pressure in Pulmonary artery and the Pressure in the LEFT atrium divided by Cardiac Output. This formula is a result of the formula: Resistance(R)=Pressure(P)/Flow(Q), where you can manipulate it to solve for different variables.

20. How do Pulmonary Vascular Resistance and Flow change with different factors?

1)Increased viscocity>Decreases Resistance

2)Increased Vessel length >Decreases Resistance

21. What does R represent and how much is it at sea level when breathing room air? How much is PIo2 under these conditions and what does it represent?

1. R represents the ratio of O2 Produced/CO2 Consumed. At sea level, when breathing room air, R is 1.2.

2. R represents the ratio of CO2 Produced/O2 Consumed. At sea level, when breathing room air, R is 1.0.

In this question, the important concept is understanding the definitions of R, PIo2, and how to calculate Alveolar Po2. The correct answer explains these concepts clearly and provides the correct calculations. The incorrect answers are designed to test the understanding of these concepts by providing common misconceptions or errors.

Explanation

In this question, the important concept is understanding the definitions of R, PIo2, and how to calculate Alveolar Po2. The correct answer explains these concepts clearly and provides the correct calculations. The incorrect answers are designed to test the understanding of these concepts by providing common misconceptions or errors.

22. Increased difference between Alveolar O2 and Arterial O2 can indicate which conditions, why?

Pulmonary embolism (PE) due to excess O2 in alveoli

High Altitude due to increased oxygen dissolved in plasma

Hyperventilation from anxiety leading to lower A-a gradient

It's important to consider different conditions and their effects on the A-a gradient to determine the correct interpretation.

Explanation

It's important to consider different conditions and their effects on the A-a gradient to determine the correct interpretation.

23. Ischemia vs Hypoxia?

Ischemia is primarily decreased O2 delivery to tissues while Hypoxia is decreased blood delivery to tissues.

Ischemia is marked by decreased O2 dissolved in plasma while Hypoxia is related to venous drainage issues.

Ischemia and Hypoxia both refer to decreased blood delivery to tissues.

24. Is ventilation More in the Apex or the base of the lung?

Ventilation is more in the Apex of the lung

Ventilation is equal in both the Apex and the base of the lung

Ventilation varies depending on the time of day

Ventilation is actually higher at the base of the lung due to the V/Q ratio, which is 0.6. This means that there is 'extra' perfusion in the base, but ventilation is still higher than in the apex. The difference in perfusion is even greater. In the apex, where V/Q=3, more O2 can be wasted/used by organisms like TB.

Explanation

Ventilation is actually higher at the base of the lung due to the V/Q ratio, which is 0.6. This means that there is 'extra' perfusion in the base, but ventilation is still higher than in the apex. The difference in perfusion is even greater. In the apex, where V/Q=3, more O2 can be wasted/used by organisms like TB.

25. Compare Pa,PV,PA at the region of lung which has V/Q of 0.6.

PV < Pa < PA

Pa < PV < PA

PA > PV > Pa

The correct order of Pa, PV, and PA at the base of the lung with a V/Q of 0.6 is Pa > PV > PA, due to the excess perfusion at the base leading to lower PaO2 than PV and PAO2.

Explanation

The correct order of Pa, PV, and PA at the base of the lung with a V/Q of 0.6 is Pa > PV > PA, due to the excess perfusion at the base leading to lower PaO2 than PV and PAO2.

26. Under physiologic conditions, which gas is diffusion limited while the others are perfusion limited?

O2 is diffusion limited, CO, CO2, and N2O are all perfusion limited.

N2O is diffusion limited, CO, CO2, and O2 are all perfusion limited.

*ONLY CO is DIFFUSION limited, CO2,O2,N2O are all PERFUSION limited.

CO2 is diffusion limited, CO, O2, and N2O are all perfusion limited.

In this scenario, CO is the only gas that is diffusion limited, meaning its rate of uptake is limited by its ability to diffuse across the alveolar-capillary membrane. CO2, O2, and N2O, on the other hand, are all perfusion limited, where their uptake is limited by blood flow through the pulmonary capillaries rather than the rate of gas diffusion.

Explanation

In this scenario, CO is the only gas that is diffusion limited, meaning its rate of uptake is limited by its ability to diffuse across the alveolar-capillary membrane. CO2, O2, and N2O, on the other hand, are all perfusion limited, where their uptake is limited by blood flow through the pulmonary capillaries rather than the rate of gas diffusion.