PhysioEx Lab Report Exercise 7 Respiratory System Mechanics

10/29/2019 PhysioEx Exercise 7 Activity 1 PhysioEx Lab Report Exercise 7: Respiratory System Mechanics Activity 1: Measuring Respiratory Volumes and Calculating Capacities Date: 29 October 2019 Pre-lab Quiz Results You scored 100% by answering 5 out of 5 questions correctly. 1 Which of the following statements describing the mechanics of breathing is false? You correctly answered: Ventilation relies exclusively on contracting skeletal muscles. 2 The contraction of which of the following muscles will increase the thoracic cavity volume during inspiration? You correctly answered: the external intercostals. 3 At the beginning of inspiration, the You correctly answered: thoracic cavity volume increases. 4 At the beginning of expiration, the You correctly answered: pressure in the thoracic cavity increases. 5 A tidal volume refers to the You correctly answered: amount of air inspired and then expired with each breath under resting conditions. Experiment Results Predict Question 1 Predict Question: Lung diseases are often classified as obstructive or restrictive. An obstructive disease affects airflow , and a restrictive disease usually reduces volumes and capacities. Although they are not diagnostic, pulmonary function tests such as forced expiratory volume (FEV 1) can help a clinician determine the difference between obstructive and restrictive diseases. Specifically, an FEV1 is the forced volume expired in 1 second. 1/6 10/29/2019 PhysioEx Exercise 7 Activity 1 In obstructive diseases such as chronic bronchitis and asthma, airway radius is decreased. Thus, FEV1 will Your answer: decrease proportionately. Stop & Think Questions 1 Which muscles contract during quiet expiration? You correctly answered: none of these muscles contract during quiet expiration. 2 Minute ventilation is the amount of air that flows into and then out of the lungs in a minute. Minute ventilation (ml/min) = TV (ml/breath) x BPM (breaths/min). Using the values from the second recorded measurement, enter the minute ventilation. You answered: 7500 ml/min. 3 A useful way to express FEV1 is as a percentage of the forced vital capacity (FVC). Using the FEV1 and FVC values from the data grid, calculate the FEV1 (%) by dividing the FEV1 volume by the FVC volume (in this case, the VC is equal to the FVC) and multiply by 100%. Enter the FEV 1 (%) for an airway radius of 5.00 mm. You answered: 73.9 %. 4 A useful way to express FEV1 is as a percentage of the forced vital capacity (FVC). Using the FEV1 and FVC values from the data grid, calculate the FEV1 (%) by dividing the FEV1 volume by the FVC volume (in this case, the VC is equal to the FVC) and multiply by 100%. Enter the FEV 1 (%) for an airway radius of 3.00 mm. You answered: 70.2 %. Experiment Data Radius (mm) Flow (ml/min) TV (ml) ERV (ml) IRV (ml) RV (ml) VC (ml) FEV1 (ml) TLC (ml) BPM 5.00 7485 499 ---- --- --- --- --- --- 15 5.00 7500 500 1200 3091 1200 4791 3541 5991 15 4.50 4920 328 787 2028 1613 3143 2303 4756 15 4.00 3075 205 492 1266 1908 1962 1422 3871 15 3.50 1800 120 288 742 2112 1150 822 3262 15 3.00 975 65 156 401 2244 621 436 2865 15 2/6 10/29/2019 PhysioEx Exercise 7 Activity 1 Baseline Airway radius = 5.00 mm Airway radius = 4.50 mm 3/6 10/29/2019 PhysioEx Exercise 7 Activity 1 Airway radius = 4.00 mm Airway radius = 3.50 mm Airway radius = 3.00 mm 4/6 10/29/2019 PhysioEx Exercise 7 Activity 1 P Y orrectly. 1 To calculate a person's vital capacity, you need to know the TV, ERV, and You correctly answered: IRV. 2 Measuring a person's FVC means that you are measuring You correctly answered: the amount of air that can be expelled when the subject takes the deepest possible inspiration and then forcefully expires as completely and rapidly as possible. 3 Measuring a person's FEV means that you are measuring 1 You correctly answered: the amount of the VC that is expired during the first second of the FVC test. 4 For a person suffering an asthma attack, inhaler medications are expected to You correctly answered: reduce the airway resistance. 5 Which of the following values does not include the ERV? You correctly answered: TV. Review Sheet Results 1 What would be an example of an everyday respiratory event the ERV simulates? Your answer: An example of an everyday respiratory event that ERV stimulates would be blowing out candles on a cake in a single breath. 2 What additional skeletal muscles are utilized in an ERV activity? Your answer: The skeletal muscles used an ERV activity are intercostal muscles and abdominals. 3 What was the FEV 1(%) at the initial radius of 5.00 mm? Your answer: 5/6 10/29/2019 PhysioEx Exercise 7 Activity 1 The FEV1 % for the radius of 5.00 mm was 73%. 4 What happened to the FEV (%) 1 as the radius of the airways decreased? How well did the results compare with your prediction? Your answer: As the radius of the airway decreased the FEV1 decreased proportionately. This can be seen in the FEV1 column as the radius of the airway goes down so does the FEV1. 5 Explain why the results from the experiment suggest that there is an obstructive, rather than a restrictive, pulmonary problem. Your answer: It suggests that there was an obstructive pulmonary problem because there is not enough oxygen getting to the lungs. 6/6