Breathing and pulmonary function

Transcription

1 EXPERIMENTAL PHYSIOLOGY EXPERIMENT 5 Breathing and pulmonary function Ying-ying Chen, PhD Dept. of Physiology, Zhejiang University School of Medicine bchenyy@zju.edu.cn

2 Breathing

3 Exercise 1: Tests of pulmonary function ---spirometry Exercise 2: Tests of chest movement

4 Spirometry Measurement of an individual s ability to inhale and exhale During the test, a subject inhales and exhales through a mouthpiece into a device called a spirometer, which records the subject s breathing capabilities mouthpiece spirometer

5 Spirogram

6 Before the spirometry test You should not to have alcohol, a heavy meal, or do vigorous exercise for a few hours before the test. Ideally, you should not smoke for 24 hours before the test Wearing loose-fitting clothes to the test is a good idea

7 Procedures The patient may be seated or standing as straight as possible Nose clips are applied to the patient to make sure that no air escapes from your nose The patient breathe in fully and then place the mouthpiece of the spirometer in his/her mouth You then blow out as fast and as far as you can until your lungs are completely empty NOTE: Create a tight seal around the mouthpiece the devices are not capable of producing highly accurate results

8 The spirometry test can evaluate at least three pulmonary functions Forced vital capacity (FVC) Forced expiratory volume in one second (FEV1) Maximum voluntary ventilation (MVV)

9 Vital Capacity (VC) is the maximum volume of air that can be exhaled after a maximal inspiration, which equals the Inspiratory Reserve Volume plus the Expiratory Reserve Volume plus Tidal Volume Forced Vital Capacity (FVC) is the maximum volume of air that can be forcibly and rapidly exhaled following a maximum inspiration Normal value: 3500mL in male and 2500mL in female

10 Forced expiratory Volume in one second (FEV1) is the volume expired in the first second of maximal expiration after a maximal inspiration and is a useful measure of how quickly full lungs can be emptied FEV1 %=FEV1/FVC= 70-90% FEV1 FVC

11 Maximum voluntary ventilation (MVV) is the maximal amount of air inspired (or expired) during one minute MVV represents respiratory function reserve; however, MVV probably is a better measure of endurance

12 Obstructive lung disease total lung capacity is normal FVC and FEV1 are reduced, because the airway obstruction FEV1% is much lower than the normal 80% Restrictive lung disease total lung capacity and FVC are reduced, because the lungs cannot be expanded as normal FEV1% is the normal 80% or an even higher percentage

13 Is there any risk in having spirometry? You may be advised not to have spirometry if you have: unstable angina had a recent pneumothorax had a recent heart attack or stroke had recent eye or abdominal surgery coughed up blood recently and the cause is not known

14 Procedure Switch on the spirometer. As the program begins, press the Enter key. Then the main menu appears on the screen Main menu Volunteer s Parameters Forced Vital Capacity Vital Capacity Maximal Voluntary Ventilation Display and Print Data

15 Press 1 key to enter the Volunteer s information menu ID number age height date Sex press 1 for male, press 2 for female Weight Input the Volunteer s information, then press Enter to return to main menu

16 Press 2 on keyboard to test Forced Vital Capacity Forced Vital Capacity press 1 to start the test take a slow deep breath (as deep as you can), put the mouthpiece in your mouth, then blow out as deep and as fast as you can When an * appears on the right corner of the screen, check the graph. Press 0 to save and return to the main menu, or press 2 to restart the test

17 Press 3 to test Vital Capacity press 1 to start the test Breath normally for at least 4 times. When you reach the end of a normal inspiration, put the mouthpiece in your mouth, then slowly blow out as deep as you can When an * appears on the right corner of the screen, check the graph. Press 0 to save and return to the main menu, or press 2 to restart the test

18 Press 4 on keyboard to test Maximal Voluntary Ventilation press 1 to start the test Breath normally for at least 4 times. Put the mouthpiece in your mouth, then breathe as forcefully as possible for 12s, until an * appears on the right corner of the screen Check the graph. Press 0 to save and return to the main menu, or press 2 to restart the test

19 Press 5 on keyboard to enter the Display and Print Data menu Return to main menu Forced Vital Capacity Vital Capacity Maximal Voluntary Ventilation Print Data

20 Analysis Record the values Respiratory parameter Forced Vital Capacity Forced Expiratory Volume in one second Vital Capacity Maximum Voluntary Ventilation Abbreviation FVC FEV1 FEV1% VC MVV Units L L % L L/min

21 Exercise 1: Tests of pulmonary function ---spirometry Exercise 2: Tests of chest movement

22 During inspiration, the diaphragm and the external intercostal muscles contract During expiration, the diaphragm and the external intercostal muscles relax

23 Regulation of respiration Involuntary control The rhythmical movements of breathing are controlled by the respiratory center in the medulla of the brain The respiratory center is stimulated by chemical changes in the blood

24 Respiration can be affected by conditions such as emotional state via input from the limbic system, or temperature via the hypothalamus Respiration can also be made voluntarily in the same way as arm and leg movements. The voluntary system is located in the cerebral cortex

25 Set up equipment Click on the RM6240USB2.0q(I)(English) icon on the Desktop Click on the Experiment menu and select the Respiration settings file Record and Zero

26 Fasten the respiratory belt around the upper abdomen of a volunteer Ask the volunteer to take deep, strong breaths and observe the signal on the screen. Adjust the Range of the Input Amplifier so that the breathing signal occupies about a half to two thirds of full scale respiratory belt

27 Normal respiration Record 2 3 minutes of normal, quiet breathing Click mark button to enter the comment inhale hold. Then take a deep breath and hold it in for as long as possible Continue recording until a normal pattern resumes. Let the volunteer rest and breathe normally for another 2 3 minutes. Click mark button to enter the comment exhale hold. then immediately breathe out fully and hold the breath for as long as possible The volunteer can now relax and breathe normally Record the following values Condition Breath hold after inhalation Breath hold after exhalation Breath hold duration (sec)

28 Hyperventilation Record the volunteer s normal respiration for 2 3 minutes Exercise on an exercise bike for 15 min. Then Record the breathing for 30 seconds Record the values Condition Normal breathing Hyperventilation Breathing amplitude (cmh 2 O) Breathing rate (breaths/min) amplitude

29 End

30 test Forced Vital Capacity : take a slow deep breath (as deep as you can), put the mouthpiece in your mouth, then blow out as deep and as fast as you can Vital Capacity : Breath normally for at least 4 times. When you reach the end of a normal inspiration, put the mouthpiece in your mouth, then slowly blow out as deep as you can Maximal Voluntary Ventilation : Breath normally for at least 4 times. Put the mouthpiece in your mouth, then breathe as forcefully as possible for 12s, until an * appears on the right corner of the screen