What is a nebulizer?
Simply put, a nebulizer is a machine that turns medication into mist that can be inhaled so that it directly reaches the respiratory tract.
Nebulizer unit
The nebulizer unit consists of a pump machine and the nebulizer set. This set consists of a chamber with an enclosed valve and a tubing. The drug in a liquid form is placed in the chamber. This chamber is connected to the pump through a plastic tubing. As the pump works, the liquid is drawn up a nozzle with resultant vapour formation.
Drugs administered through nebulizer
The commonly used drugs are bronchodilators such as salbutamol, steroids, ipratropium bromide, antibiotics such as tobramycin , racemic epinephrine and mucolytics such as acetylcysteine. Normal saline is used alone by itself or as the medium for the dilution of the drugs. It helps in breakdown of the secretions. Use of distilled water is contraindicated for it may worsen the bronchospasm and cause distress. A maximum of 5 ml of normal saline is used for at least 10 minutes. It is essential that for proper hygiene and asepsis, each patient should have his own nebulizer set.
Indication:
- Bronchiolitis and nose blocks
Normal saline help to liquefy the secretions - Croup
Racemic epinephrine diluted in saline decreases the edema (swelling) of the larynx in severe cases. - Cystic fibrosis
It is not so common in India but antibiotics are given directly by nebulizer - Bronchiectasis
Acetylcysteine in saline helps to break down the thick secretions - Asthma
The use of a nebulizer machine for asthma is controversial
In Asthma, the patient’s are expected to take albuterol, steroids and ipratropium through a Metered Dose Inhaler (MDI) with the help of a spacer. These drugs can only be used with the nebulizer set without the pump but driven by oxygen flow in a hospital setting only. The logic is to avoid patients to repeatedly and unnecessarily take the bronchodilator drugs,a beta agonist causing myocardial ischemia( decreased blood flow to heart tissue) resulting in deaths. Also studies have shown that asthma drugs delivered by MDI plus spacer are as effective as by nebulizer without oxygen. Moreover, it is cumbersome to use repeatedly. There are now hand held nebulizer pumps available but their effectiveness is questionable , so much so that in the UK home nebulizer for asthma is banned. In the hospital the bronchodilator drugs are driven through the chamber with the help of oxygen flow at the rate of minimum 6L per minute.
In India patients routinely using nebulizer machine and this practice needs to be discouraged.