Chapter 7: Respiratory Nursing — COPD, Asthma, and Airway Management

Respiratory disorders account for millions of hospitalizations annually. The nurse’s ability to rapidly assess respiratory status, interpret arterial blood gases, and implement evidence-based interventions directly impacts patient survival.

COPD vs. Asthma

Feature	COPD	Asthma
Primary cause	Smoking (90%), occupational exposures	Allergies, irritants, exercise, infections
Airflow obstruction	Irreversible (partially reversible)	Reversible
Typical patient	> 40 years, smoking history	Often younger, allergic history
Breath sounds	Diminished, prolonged expiration, wheezing	Wheezing (may be absent in severe attack)
Sputum	Chronic productive cough	Clear or white (purulent in infection)
Gold standard dx	Spirometry: FEV₁/FVC < 0.70 post-bronchodilator	Spirometry showing reversible obstruction

COPD Nursing Priorities: Low-flow oxygen (target SpO₂ 88–92% in hypercapnic COPD patients to avoid blunting hypoxic drive), bronchodilators, positioning (tripod), energy conservation, smoking cessation, pulmonary rehabilitation.

Asthma Status Asthmaticus: life-threatening attack unresponsive to initial bronchodilators. Requires IV corticosteroids, magnesium sulfate, possible intubation. A silent chest (no wheezing due to minimal air movement) is an ominous sign.

ABG Interpretation

Use the ROME mnemonic to determine primary disorder:

• Respiratory Opposite: pH and PaCO₂ move in opposite directions
• Metabolic Equal: pH and HCO₃ move in the same direction

Parameter	Normal	Acidosis	Alkalosis
pH	7.35–7.45	< 7.35	> 7.45
PaCO₂	35–45 mmHg	> 45 (respiratory)	< 35 (respiratory)
HCO₃	22–26 mEq/L	< 22 (metabolic)	> 26 (metabolic)
PaO₂	80–100 mmHg	—	—
SpO₂	95–100%	—	—

Steps: (1) Is pH normal? (2) Is PaCO₂ or HCO₃ abnormal? (3) Does the abnormal value explain the pH change? (4) Is there compensation?

Oxygen Therapy

Device	FiO₂ (%)	Flow Rate (L/min)	Notes
Nasal cannula	24–44	1–6	Comfortable; FiO₂ variable
Simple face mask	40–60	6–10	Minimum 6 L to flush CO₂
Partial rebreather	60–75	10–15	Reservoir bag must stay inflated
Non-rebreather	80–95	10–15	One-way valves; highest FiO₂ without intubation
Venturi mask	Precise 24–50	Varies	Best for COPD (controlled FiO₂)

Airway Management

Positioning: Semi-Fowler’s (30–45°) or high-Fowler’s optimizes diaphragmatic excursion. Tripod position (leaning forward, arms on knees) is commonly self-adopted by COPD patients.

Suctioning: Use sterile technique; suction for ≤ 10–15 seconds; pre-oxygenate; monitor SpO₂ and cardiac rhythm. Nasotracheal suctioning is more stimulating; use lubrication.

Incentive Spirometry: Goal is to prevent atelectasis post-operatively. Teach 10 sustained maximal inspirations per hour while awake.

Nebulizer Treatments: Short-acting beta-2 agonists (albuterol/salbutamol) are first-line bronchodilators. Teach: sit upright, breathe slowly and deeply, treatment takes 10–15 minutes.

Key Checklist

• Explain why COPD patients require controlled low-flow oxygen rather than high-flow, and state the target SpO₂ range
• Interpret an ABG of pH 7.28, PaCO₂ 55, HCO₃ 24 and identify the disorder and compensation status
• Describe the correct technique for endotracheal suctioning, including duration, pre-oxygenation, and monitoring