I had a patient the last 2 days on 25 of PEEP. The docs were concerned about her lungs
"popping," so for a while- we didn't move her. Finally, got it down to 15. What's the highest PEEP you've seen, and have you ever had a patient's lungs pop?
25 is the highest that you will see for the most part. To need to be on 25 of PEEP the pts lungs are usually very non-compliant because of ARDS, and the risk for barotrauma is high with these patients.
I have seen pneumothoracis associated with PEEP settings this high because there Plateau Pressures are usually elevated also. To minimize the risk pneumothorax the use of low tidal volume strategies should be employed.
this pt was finally stabilized on 25 peep, cmv, tv 450, rate 35. can you tell me a little about the plateau pressures and the pneumothoracis? Also, at what point does resp. distress actually become defined as "ARDS"? Thanks!
I am going to recommend that you visit www.icufaqs.org, this web site will be able to answer a lot of your questions. Get a good ICU book, as nursing school books to not go into enough depth about respiratory and hemodynamics problems as you will need to know and understand to be an ICU nurse.
Plateau pressures are obtained by doing an inspiratory hold on the ventilator. When you do this the ventilator gives you the peak alveolar pressure. Ideally this number should be < 30. Numbers greater then 30 are associated with higher rates of barotrauma (pneumothorax), and volutrauma (lung parenchymal injury). Essentially the pressure in the alveoli becomes to great in relationship with the poor compliance of the lungs so they are at risk to "pop"(pneumo).
Respiratory distress becomes defined as ARDS when you have bilateral infiltrates on CXR, with a PaO2 to FiO2 ratio of < 200 (PaO2 of 50 with a FiO2 of 1.0 = a PaO2/FiO2 ratio of 50). This needs to be in the presence of a PAOP of less then or equal to 18 so that it is not related to cardiac dysfunction.