This is seriously one of my favorite cheatsheets.Working in the ICU, I have grown fond of respiratory therapy and ventilators.Needless to say, ventilation can be pretty confusing and I think we push it to the side because of this.Today's cheatsheet is something I made up after working in the ICU for several months to help me keep straight the hierarchy for oxygen support. Â While this is not cut and dry, it does provide you with what to expect if a patient is ventilating poorly.