I see your predicament. I talked a bit about this in an earlier post. With 2 broken ribs I once could not cough without pain for 6 weeks, although the first 2 weeks were the most difficult. Even with painkillers, fully coughing presented a deep and stinging pain. But the cough always won. The impuls to clean the airways is stronger than the want to prevent pain. The body will take care of this. Once in deep pain from coughing, I found out it was easy to go on coughing even harder because the deep pain was already there and could’t get worse. Only the moaning did. So I always did my clearance routine, modified perhaps, and went through the pain.
To be more comfortable I timed my pain medication wisely to be strongest at the times of my airway cleaning routines in the morning and evening. I tried to breathe with autogenic drainage and withhold my cough as long as possible to minimize coughing frequency and maximize the output.
Also I preventively took a strong course of antibiotics to bring the infection back to the lowest possible level, thus minimizing sputum production. Another time when I needed an appendectomy, I started the antibiotics before the operation and continued until the wound was healed and coughing was less painful.
Because of sleeping badly, there was less sputum in the morning. Nature provides solutions for free.
Try not to worry too much in advance. Your body will find the strength and surprising solutions in the moment it is needed spontaneously, much easier than your limited mind can imagine now in advance. The power of Now will come to your assistance in abundance. Trust is the best preparation.
Namaste,
Paul