This book was initially started to help with understanding and organizing what I needed to know about the two most common NIMV (noninvasive mechanical ventilation) units, ie. Trilogy and Astral. As I presented this information at various lectures, it was clear to me that there was no guide that could be used in the setup of these machines. The most common mode of ventilation in each was AVAPS and iVAPS, respectively. Most of the initial difficulty is getting into the main menus of the machines. Once this is accomplished, one can easily change and adjust each of the machines. My hope is to impart the knowledge I have gained out of necessity to others. The hope is to have a step-by-step method of entering the menu and then moving through the various settings. I have concentrated on the two main modes of ventilation on each of the machines as the other modes available are variations on the two main modes. As one understands and allows for more experience with these machines, it will hopefully allow for more expertise in these field. In the NIMV clinic, I have patients sit in a recliner and then I place them on these machines with a mask of the patient's choosing. Then based on trial and error, start adjusting the pressures. Once the pressures and settings feel right to the patient, I allow the patient to recline and take a small nap. While they are napping, I have a continuous pulse oximetry, which can be added to these machines, to monitor the oxygen saturation. By the end of the clinic, I have the exact settings and give this to the DME (Durable Medical Equipment) company. In follow up, I know exactly what the settings are and if they are tolerable to the patient.