A 68-year-old with COPD has worsening dyspnea and purulent sputum. Findings are RR 28/min, SpO2 84% on room air, pH 7.30, PaCO2 62 mmHg, PaO2 56 mmHg, and HCO3 30 mEq/L. Which initial actions are appropriate? Select all that apply.
Select All That Apply
Choose your responses, then check the answer.
Explanation
This client has an acute COPD exacerbation with acute-on-chronic hypercapnic respiratory acidosis. Give controlled oxygen titrated to 88% to 92% and reassess gas exchange; the concern with excessive oxygen is worsening hypercapnia through mechanisms such as ventilation-perfusion mismatch and the Haldane effect, not simple loss of a 'hypoxic drive' (Choice 1). Upright or tripod positioning and pursed-lip breathing can reduce work of breathing (Choice 4). Short-acting bronchodilators are initial treatment (Choice 6), and prescribed systemic corticosteroids and antibiotics should not be delayed when indicated (Choice 2). Supine positioning and suppressing productive cough impair ventilation and secretion clearance (Choice 3). Uncontrolled oxygen targeting 100% can worsen hypercapnia; because pH is 7.30, the team should also assess promptly for noninvasive ventilation (Choice 5).
COPD Acute Exacerbation — Initial Care 1. Controlled low-flow O2 nasal cannula 1-2 L/min, titrate to SpO2 88-92% (avoid 100% in CO2 retainer) 2. Nebulized SABA + SAMA: albuterol + ipratropium (DuoNeb) 3. Systemic corticosteroid: prednisone 40 mg PO × 5 days or methylprednisolone IV 4. Antibiotics if increased sputum purulence + volume + dyspnea (Anthonisen criteria) 5. Position: high-Fowler/tripod; pursed-lip breathing 6. Reassess: SpO2 trend, RR, mental status, ABG if not improving — escalate to BiPAP if hypercapnia/acidosis worsens
ABG in COPD This client: pH 7.30, PaCO2 62, HCO3 30 → acute on chronic respiratory acidosis with partial metabolic compensation. Chronic baseline likely had pH 7.36-7.40 and PaCO2 50-55; now acutely worse.
Why Avoid 100% Oxygen Chronic CO2 retainers depend partly on the hypoxic respiratory drive. Excess oxygen → suppresses drive → CO2 rises further → respiratory acidosis worsens → CO2 narcosis and respiratory arrest. Target SpO2 88-92%.
Pursed-Lip Breathing Inhale slowly through the nose; exhale slowly through pursed lips for ~4-6 seconds. Generates internal PEEP, prevents premature airway collapse, and reduces dynamic hyperinflation.
Memory Tip "88-92 + DuoNeb + Steroid + Sit Up"
Scenario68 yo with long-standing COPD, 3 days of dyspnea + thick yellow sputum + wheezing. RR 28, SpO2 84% RA, ABG pH 7.30/PaCO2 62/PaO2 56/HCO3 30 = acute on chronic respiratory acidosis.
Initial Care Bundle1. Controlled O2 NC 1-2 L/min → SpO2 88-92%2. Nebulized albuterol + ipratropium (SABA + SAMA)3. Systemic corticosteroid (prednisone PO or methylprednisolone IV)4. Consider antibiotics (purulent sputum + volume + dyspnea)5. High-Fowler/tripod + pursed-lip breathing + calm presence6. Reassess; escalate to BiPAP if worsening hypercapnia/acidosis
Avoid- 100% non-rebreather targeting 100%- Supine positioning- Suppressing cough- Waiting on repeat ABG before treating
COPD Acute Exacerbation — Acute worsening of COPD symptoms (dyspnea, cough, sputum volume/purulence) beyond day-to-day variation that requires escalation of therapy. Often triggered by viral or bacterial respiratory infection, environmental pollution, or non-adherence. First-line: controlled low-flow oxygen titrated to SpO2 88-92%, nebulized short-acting beta agonist + anticholinergic (albuterol + ipratropium), systemic corticosteroid (prednisone 40 mg PO daily for 5 days), and antibiotics when purulence is increased. Escalate to noninvasive ventilation (BiPAP) if hypercapnia and acidosis worsen.
Controlled Oxygen Therapy in CO2 Retainers — Chronic CO2 retainers (often advanced COPD) may depend partly on hypoxic respiratory drive. Excessive supplemental oxygen can suppress this drive, worsen ventilation-perfusion mismatch, and increase CO2 — precipitating CO2 narcosis and respiratory arrest. Standard: titrate oxygen to SpO2 target 88-92% rather than 95-100%, using the lowest effective FiO2 (often nasal cannula 1-2 L/min). Reassess frequently; if SpO2 cannot be maintained at target with low-flow O2, escalate to BiPAP rather than high-flow oxygen alone.
ABG Interpretation in COPD — Chronic CO2 retention typical baseline: pH 7.36-7.40, PaCO2 50-55, HCO3 28-32 (chronic respiratory acidosis with metabolic compensation). Acute exacerbation: pH falls (often <7.35 or <7.30 if severe), PaCO2 rises further, HCO3 already elevated from compensation. The pattern in this client (pH 7.30, PaCO2 62, HCO3 30) is acute on chronic respiratory acidosis with partial metabolic compensation. NIPPV (BiPAP) is indicated when pH <7.35 with hypercapnia despite optimal medical therapy.