Plethysmography

This is part of my 2nd year medicine course. I find it quite frustrating that we're told to "learn" how this method works, yet few sources bother to explain how measuring a couple of pressures actually enables you to get the total long volume / residual capacity /... This video focuses exactly on that, and omits all the unnecessary details. Source (and for more details, see): "Body plethysmography – Its principles and clinical use" – C.P. Criée, S. Sorichter, H.J. Smith, P. Kardos, R. Merget, D. Heise, D. Berdel, D. Köhler, H. Magnussen, W. Marekp, H. Mitfessel, K. Rasche, M. Rolke, H. Worth, R.A. Jörres,– Working Group for Body Plethysmography of the German Society for Pneumology and Respiratory Care. http://www.resmedjournal.com/article/S0954-6111(11)00055-2/fulltext