What is a critical step when performing postural drainage?

The critical step of coughing after each set of vibration in postural drainage serves an important purpose in the overall effectiveness of the treatment. Coughing helps to clear mucus and secretions from the airways. During postural drainage, the position of the body is altered to facilitate the movement of mucus from the lungs into the larger airways, where it can be expelled more easily. Performing vibrations during the drainage can loosen secretions, and coughing acts as an effective mechanism to help remove these loosened secretions from the respiratory tract.

In contrast, other choices do not align with the primary goals of postural drainage. While applying heat may seem beneficial, it is not a standard practice directly associated with facilitating mucus clearance during postural drainage. Suction machines typically are used in more acute scenarios or when the patient cannot effectively cough on their own, rather than as a routine part of postural drainage. Additionally, squatting while percussing is not a usual recommendation since it may not provide the best position for airway clearance. Thus, coughing after vibrations is essential as it maximizes the treatment's effectiveness in clearing mucus from the lungs.