During the post-operative period, patients are often very weak and need aggressive rehab to regain their strength. There can be several causes that require a person to use CPAP, including complications of lung function following surgery (infection, lung collapse, fluid in the lungs, etc). Lung failure in these cases are typically temporary and resolve with treatment of the underlying cause. This process may take a while (days to weeks) during which time intermittent use of CPAP may be used.
Thank you a lot for the answer. The CPAP is been used now for 17 days. Doctors said that they will apply the Tracheotomy (temporarily) if my father's respiratory function is not fully improved.
Thank you again