Exercise 7: Respiratory System Mechanics Worksheet Assignment Due: Week 7 Student instructions: Follow the step-by-step instructions for this exercise found in your text and record your answers in the spaces below. Submit this completed document by the assignment due date found in the Syllabus. Please make sure that your answers are typed in RED. Respiratory Volumes Activity 2: Measuring Normal Respiratory Volumes 1. Minute respiratory volume: 7,500 ml 2. Judging from the trace you generated, inspiration took place over how many seconds? 2 seconds 3. Expiration took place over how many seconds’seconds 4. Does the duration of inspiration or expiration vary during ERV or FVC? Yes Activity 3: Effect of Restricted Air Flow on Respiratory Volumes 1. How does this set of data compare to the data you recorded for Activity 2? The MRV is 3075 and the breathing is not as strong. 2. Is the respiratory system functioning better or worse than it did in the previous activity? It is worse. Explain why. The breathing is more shallow and incomplete. The lungs are not able to inhale or exhale as much as in Activity 2 3. What is the effect of reducing the radius of the air flow tube on respiratory volumes?
The air flow was decreasing, which decreased the respiratory volume. 4. What does the air flow tube simulate in the human body? The trachea 5. What could be some possible causes of reduction in air flow to the lungs? An allergic reaction could cause the trachea to swell which would restrict air flow or an obstruction could block some or the entire trachea causing the air flow to decrease as well. Factors Affecting Respiration Activity 4: Effect of Surfactant on Respiratory Volumes 1. When surfactant is added, what happens to the tidal volume? It increases the amount of air being inhaled 2.
As a result of the tidal volume change, what happens to the flow into each lung and total air flow? The air flow increases into the lungs and the total air flow increases 3. Why does this happen’surfactant allows the wet surface of the alveoli to expand and not stick together. Activity 5: Effect of Thoracic Cavity Puncture 1. What happened to the left lung when you clicked on the valve button? It collapsed and lost the ability to fill with air 2. Why? Because it is no longer has one way in and one way out. The opened valve does not allow air to enter and stay in the lung to become oxygenated. . What has happened to the “Total Flow” rate? It decreased 4. What is the pressure in the left lung? 0 5. Has the pressure in the right lung been affected? No 6. If there was nothing separating the left lung from the right lung, what would have happened when you opened the valve for the left lung? It would also collapse Why? There would be nothing separating them so they would act as one lung. If the valve opened, it would have the same affect on both as what happened to the left lung when the valve was opened. 7. Now click the valve for the left lung again, closing it. What happens?
It stays collapsed. Why? The lungs valve was only closed, but the lung itself was not repaired. 8. Describe the relationship required between intrathoracic pressure and atmospheric pressure in order to draw air into the lungs. The intrathoracic pressure has to be the opposite of the atmospheric pressure in order to cause the air to be pulled into the lungs. 9. Design your own experiment for testing the effect of opening the valve of the right lung. Was there any difference from the effect of opening the valve of the left lung? No Variations in Breathing Activity 6: Rapid Breathing . What happens to the PCO2 level during rapid breathing? It decreased 2. Why? The breathing became quick and very shallow so the amount of oxygen being inhaled was less. Activity 7: Rebreathing 1. What happens to the PCO2 level during rebreathing? 2. Why? The breathing became deeper and more oxygen was inhaled with each breath. 3. Did the total flow change? Yes it increased 4. Why? More oxygen was being taken in with each breath 5. How does the rebreathing trace compare to your baseline trace? The inhales and exhales become deeper and the get deeper with each breath 6. Why?
Rebreathing happens to try and reoxygenate the body to a normal level and to bring the heart beat back to a normal level. Activity 8: Breath Holding 1. What happens to the PCO2 level during breath holding? It increases 2. Why? All the oxygen from the breath is being held in and nothing is being expelled. 3. What change was seen when you returned to “Normal Breathing”? The breathing resembled rebreathing and the PCO2 level increased even more. Activity 9: Comparative Spirometry Normal Breathing: What do you think is the clinical importance of the FVC and FEV1 values? It measures the strength and health of the lungs 1.
Why do you think the ratio of these two values is important to the clinician when diagnosing respiratory diseases? To see if a person is equal in the FVC and FEV1, depending on this could give a better insight on determining the problem. Emphysema Breathing: 2. Is the FVC reduced or increased? Decreased 3. Is the FEV1 reduced or increased? Decreased 4. Which of these two changed more? FEV1 5. Explain the physiological reasons for the lung volumes and capacities that changed in the spirogram for this condition. The amount of air being pulled into the lungs was decreased and the amount of air the lungs could hold was decreased.
Acute Asthma Attack Breathing: 6. Is the FVC reduced or increased? Increased 7. Is the FEV1 reduced or increased? Decreased 8. Which of these two changed more? FVC 9. Explain the physiological reasons for the lung volumes and capacities that changed in the spirogram for this condition. The air flow is being blocked so the volume of air going into the lungs is a lot less. 10. How is this condition similar to having emphysema? Both conditions restrict the airway. How is it different? In asthma, the windpipes gets blocked my mucus, in emphysema, the alveoli in the lungs get clogged by mucus. 11.
Emphysema and asthma are called obstructive lung diseases as they limit expiratory flow and volume. How would a spirogram look for someone with a restrictive lung disease, such as pulmonary fibrosis? It would look similar as the volume of the lungs would decrease but the breaths would not be quick, only shallow. 12. What volumes and capacities would change in this case, and would these values be increased or decreased? FVC,FEV,TLC, IRV would decrease, IRV increase 13. In an acute asthma attack, the compliance of the lung is decreased, not increased as it was for emphysema, and air flows freely through the bronchioles.
Therefore, will the FEV1/FVC percentage be less than normal, equal to normal, or higher than normal? Less than normal Acute Asthma Attack Breathing with Inhaler Medication Applied: 14. Has the FVC reduced or increased? Is it “normal? Increased 15. Has the FEV1 reduced or increased? Is it “normal”? Increased 16. Which of these two changed more? FEV1 17. Explain the physiological reasons for the lung volumes and capacities that changed in the spirogram with the application of the medication. The medication allows the airways to open up more so that more oxygen can enter the lungs and the amount of oxygen the lungs can hold also increases.
