|
Aerosols |   |
Advantages and Disadvantages of Aerosol Therapy
Aerosol generation and delivery to the lung is a complex and dynamic topic, with clinicians and researchers finding out more about its dynamics every day. The aerosol route of drug administration has become a preference for those treating pulmonary disease for a variety of reasons. The advantages of aerosol delivery of drugs include:
- Aerosol doses are smaller than those for systemic treatments.
- Onset of drug action is rapid.
- Drug delivery is directly targeted to the respiratory system.
- Systemic side effects are fewer and less severe than with oral or
parenteral therapy
- Inhaled drug therapy is painless and relatively convenient.
As with nearly everything that has advantages, aerosol delivery of drugs also has its disadvantages, including:
- Special equipment is often needed for its administration.
- Patients generally must be capable of taking deep, coordinated breaths.
- There are a number of variables affecting the dose of aerosol drug
delivered to the airways.
- Difficulties in dose estimation and dose reproducibility.
- Difficulty in coordinating hand action and breathing with metered
dose inhalers.
- Lack of physician, nurse, and therapist knowledge of device use and
administration protocols.
- Lack of technical information on aerosol producing devices.
- Systemic absorption also occurs through oropharyngeal deposition.
- The potential for tracheobronchial irritation, bronchospasm, contamination, and infection of the airway.
The common hazards of aerosol therapy are:
Airway obstruction - Dehydrated secretions in the patient's airways may absorb water delivered via aerosol and swell up large enough to obstruct airways. To avoid this, watch the patient very closely and let him progress with therapy at a reasonable rate. You may want to have suction apparatus on hand.
Bronchospasms - It is common for aerosol particles to cause this condition (especially among asthmatics) and it is more prevalent when administering a cold aerosol as compared to a heated one. If a very large amount of coughing occurs, stop therapy and give the patient a rest. If this persists in farther therapy, stop treatment and notify the physician.
Fluid overload - This can occur when administering continuous aerosol therapy. It can happen quite frequently when treating infants or patients in congestive heart failure, renal failure or patients who are very old and immobile. In the infant, because of the smaller body size and possible underdeveloped fluid control mechanism, a quantity of water that an adult can easily handle will cause fluid overload. In a patient with congestive heart failure, any addition of fluid to the vascular system will put an increased strain on the heart. In a patient with renal failure who is probably already in fluid overload, it is easily seen that you will not want to increase the fluid volume. In older patients, the fluid control mechanisms may be impaired due to age.