Try to describe the principles of postural drainage in patients with bronchiectasis.

The principles of postural drainage in patients with bronchiectasis are as follows. According to the lesion site, the patient's experience (consciously conducive to coughing position) to take the appropriate position, in principle, elevate the position of the affected lung, drainage bronchial opening downward, and is conducive to the retention of secretions with the effect of gravity to flow into the large bronchial tubes and trachea, so as to be discharged.