Why can a nebulizer in children cause pneumonia?

What is a surfactant complex?

A surfactant (surface-active substance) — is a mixture of lipids and proteins produced by type II alveolar cells in the lungs. Its main functions are:

• To reduce surface tension in the alveoli, preventing them from collapsing during exhalation.
• To ensure normal gas exchange and elasticity of lung tissue.
• To protect the lungs from infections, serving as part of the innate immunity.

In children, especially newborns, the surfactant complex is still immature, and in weakened or frequently ill children, it may be damaged or depleted. It can also be depleted on a high-carbohydrate diet without sufficient fats and proteins in the diet.

How does a nebulizer work?

A nebulizer turns liquid medication into an aerosol that is inhaled through a mask or mouthpiece.

The most commonly used are:

• Bronchodilators (salbutamol, berodual);
• Glucocorticoids;
• Mucolytics;
• Saline solutions, mineral waters, and antiseptics.

Why can a nebulizer be harmful?

Irritation and destruction of surfactant. Many substances, especially hyperosmolar solutions, alcohol-containing preparations, or frequent use of antiseptics, can damage surfactant, making the alveoli vulnerable to collapse and microtraumas. This creates conditions for local inflammation and secondary bacterial infection, i.e., pneumonia.

Disruption of the natural defense of the respiratory tract. Frequent humidification of the airways with impaired mucociliary activity can dilute mucus, disrupting the barrier function. This increases the permeability of the epithelium and facilitates colonization by pathogenic microflora.

Formation of areas of stagnant fluid. With a weakened cough reflex and impaired mucus drainage due to immature bronchi, aerosol liquids can accumulate in the bronchioles and alveoli, promoting the development of a moist environment favorable for bacteria.

Why is it especially dangerous for children?

• Small diameter of the airways — more easily obstructed by inflammation or mucus.
• Weak mucociliary activity — poor sputum drainage.
• Immature immune system — weak control over bacterial flora.
• Deficiency or instability of surfactant — lungs collapse more quickly, disrupting ventilation.

Conclusion

Frequent use of nebulizers in children with an immature or weakened surfactant complex can lead to:

• Damage to the alveoli,
• Stagnation in the lungs,
• Disruption of natural drainage and cleansing of the airways,
• Increased risk of inflammation of lung tissue, i.e., pneumonia.