Severe pneumonia that has been on a ventilator for 5 days without improvement may be a natural course of the condition that requires continued treatment, or it may require adjustments in medication and treatment regimen. Severe pneumonia is pneumonia that requires ventilation support and has serious complications such as circulatory and respiratory dysfunction. Usually five days after being put on a ventilator, its not long enough to continue treatment as most severe pneumonias have a natural course of more than five days. However, it may be necessary to adjust the medication regimen, improve the pathogenetic tests, such as blood culture and serologic culture, to determine the specific pathogens, and you can use some sensitive antibiotics, such as vancomycin and linezolid. Severe pneumonia can also be combined with immunosupportive therapy such as gammaglobulin to help the patient through. Combine this with sputum aspiration, sputum chemigation with ambroxol, nebulization such as budesonide, and supportive therapy. In conclusion, if severe pneumonia does not improve after five days on the ventilator, you should actively improve other tests to determine whether you need to change your medication regimen or maintain your current regimen, and the above medications should be applied in accordance with your doctor’s instructions.