This comes up a lot, but unlike ventilator waveforms the loops are not a part of the ICU routine. In fact the analysis of pressure-volume and flow-volume loops adds little to one's management. For instance, unreliablility of pressure-volume loops has been demonstrated in the context of determining the ideal PEEP in ARDS. Usually, the college expects the candidates to draw the pressure-volume curves of a patient with reduced compliance (compared to normal), and the flow-volume graphics tend to be the "scooped out" loops of bronschospasm.
SAQs which have required the analysis of loops include the following:
This is a brief summary, and will not go into great depth. Locally, a long discussion of the shape of the pressure-volume loop and the flow-volume loop is available. For a formal discussion of loops, particularly as related to formal spirometry, one could do worse than the 1973 "A Current Perspective" by Hyatt and Black, from the American Review of Respiratory Disease. The ideal way to present this information is with actual spirometry diagrams, especially considering that the college SAQs on this topic typically either come in the form of diagrams, or call upon the candidate to draw diagrams.
In summary, the following useful information can be derived from them:
Limitations of the loops are as follows: