Physiology practical demonstrations - Vitalography

In this short video, Dr. Terry Gleave (University of Liverpool, UK) gives a demonstration of a clinical test of the respiratory system using a Vitalograph; a device used to analyse both static and dynamic lung volumes. This video has been adapted from a Massive Online Open Course (MOOC), titled 'Physiology: The Science of Life', which ran in 2018 and 2019. The course was developed in partnership between The Physiological Society and the University of Liverpool and was hosted on FutureLearn. Transcript: So what we're going to do is a demonstration of the vitalograph, a clinical lung function test looking at your dynamic lung volumes, essentially looking at the amount of air that you can get in and out of your lungs over a period of time. So what i need you to do first of all, is put your nose clip on so we ensure that all the breathing is just through your mouth. And then if you want to pick up the mouthpiece. And the first action you're going to take is the biggest possible breath in that you can, followed by the biggest exhalation again so that we can see how big your lungs are. So it's the vital capacity. You'll also notice that the pen's on zero, and we're on a calibrated sheet. okay. Don't worry if you don't see anything move apart from the pen, because the trolley shouldn't move. We're on zero at the moment. So if you can do that, take the biggest possible breath in you can, the biggest exhalation. And let's see how big your lungs are. Excellent. Thank you very much. So you saw the pen come up on the chart recorder. You can see that it's made its indentation. And you've got a vital capacity of 3.85, is that? Just short of 3.9 litres. Yeah. So this time, pressing the switch so now the trolley is going to move at a rate of sort of kind of one quarter inch a second. Essentially, as you see the trolley move, you're looking to get as much of the air out of your lungs as you possibly can within that first second, and then maintain that exhalation for at least six seconds. Okay. Okay. So again, take the biggest possible breath in that you can, and then exhale as hard and as fast. But this time, maintain that exhalation again. okay So if you can do that for me, please. That's it. And keep breathing out, keep breathing out. Keep going, keep going, keep going. And there you can relax. That's great. Thank you very much. So as the trolley was moving back, you can see that it gave us the vital capacity. And then you can also see that, as you were exhaling and the trolley was moving, by the time you got to one second, you'd moved 3.6 litres of gas out of your lungs. Yeah. So it's indicative that you've got about 70% to 80% of the air out of your lungs, which shows a healthy lung function. And then as we follow further over, you can see you get your forced vital capacity, which is coming close to four litres. Excellent. Thank you very much. Thank you.