Other Respiratory Care Techniques

OTHER RESPIRATORY CARE TECHNIQUES

Other respiratory care techniques, including admin-istration of aerosolized water or bronchodilators and clearing of pulmonary secretions, preserve or improve pulmonary function.

An aerosol mist is a gas or gas mixture contain-ing a suspension of liquid particles. Aerosolized water may be administered to loosen inspissated secretions and facilitate their removal from the tra-cheobronchial tree. Aerosol mists are also used to administer bronchodilators, mucolytic agents, or vasoconstrictors (metered-dose inhalers are preferred for administration of bronchodilators). A normal cough requires an adequate inspiratory capacity, an intact glottis, and adequate muscle strength (abdominal muscles and diaphragm). Aerosol mists with or without bronchodilators may induce cough as well as loosen secretions. Instilla-tion of hypertonic saline has been used as a muco-lytic and to induce cough. Additional effective measures include chest percussion or vibration ther-apy and postural drainage of the various lung lobes.

Maneuvers that produce sustained maximum lung inflation such as the use of an incentivespirometer can be helpful in inducing cough as well as preventing atelectasis and preserving normal lung volume. Patients should be instructed to inhale approximately 15–20 mL/kg and to hold it for 2–3 s before exhalation.

When thick and copious secretions are associ-ated with obvious atelectasis and hypoxemia, more aggressive measures may be indicated. These include suctioning the spontaneously breathing patient via a nasopharyngeal catheter or flexible bronchoscope, or performing the same two maneuvers through a tracheal tube. When there is atelectasis without retention of secretions, a brief period of CPAP by mask or positive-pressure ventilation through a tra-cheal tube is often very effective.