Which technique can be used to improve airway clearance for a patient with a weak cough?

Mechanical insufflation-exsufflation (MIE) is an effective technique for improving airway clearance in patients with a weak cough. MIE works by delivering a positive pressure breath that inflates the lungs, followed by a rapid switch to negative pressure that assists in the expulsion of air from the lungs. This method mimics the natural cough reflex, helping to mobilize secretions and enhance expectoration, particularly in patients who may struggle with effective coughing due to reduced muscle strength or neuromuscular conditions.

The machine used for MIE can be particularly advantageous for patients who cannot generate a strong cough on their own, as it takes over the effort of both inhalation and exhalation, providing critical respiratory support while promoting airway clearance. This makes it especially suitable for individuals with conditions that lead to ineffective cough, such as muscular dystrophy or spinal cord injury.

Other techniques, while helpful for airway clearance, may not be as specifically beneficial for those with weak cough reflexes as MIE. Postural drainage, percussion, PEP, and Active Cycle of Breathing each have their roles in promoting secretion clearance but primarily rely on the patient actively participating in the process.