Asthma and COPD

Both are obstructive diseases: the difficulty is getting air out, not in. Airways collapse or narrow during exhalation, trapping air distally. This is why the expiratory phase lengthens and why patients develop hyperinflation over time.

The critical difference is reversibility. Asthma is episodic, inflammatory, and largely reversible between attacks — the patient can be entirely well. COPD involves permanent structural change and is progressive; management slows decline and controls symptoms rather than restoring normal function.

An attack presents with wheezing, chest tightness, a dry cough, prolonged expiration, and accessory muscle use.

A silent chest is an emergency. When wheezing disappears in a patient who is still working hard to breathe and remains distressed, it usually means airflow has dropped too low to generate sound. This is deterioration, not improvement. It is the single most important recognition point in this topic.

Watch also for a falling peak flow, inability to speak in full sentences, and rising then falling oxygen saturation.

Chronic findings include a barrel chest from long-term air trapping, pursed-lip breathing, tripod positioning, chronic productive cough, and clubbing over time.

Pursed-lip breathing is a self-taught compensation worth reinforcing — it creates back-pressure that splints airways open during exhalation.

On oxygen: some COPD patients chronically retain CO₂, and the concern historically taught is that high-flow oxygen can blunt respiratory drive. The practical takeaway for the bedside is to titrate oxygen carefully to the ordered target saturation rather than maximising it, and to monitor respiratory rate and level of consciousness during any change. Hypoxia is still treated — an acutely hypoxic patient receives oxygen.

Patients confuse these constantly, and clarifying it is one of the higher-impact pieces of teaching in respiratory nursing.

Rescue — short-acting beta agonists such as albuterol. Fast onset, taken during symptoms. Expect tachycardia, tremor, and jitteriness.

Controller — inhaled corticosteroids such as fluticasone. Taken daily regardless of symptoms, and useless during an attack because they take weeks to reach effect.

When both are prescribed, the bronchodilator goes first, then wait, then the steroid — the open airway lets the steroid reach further down.

Always teach rinsing the mouth after an inhaled corticosteroid to prevent oral candidiasis.