Chronic obstructive pulmonary disease exacerbation resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Abdurahman Khalil, M.D. [2]

Definition

• Exacerbation of COPD is an acute event characterized by a worsening of the patient’s respiratory symptoms that is beyond normal day-to-day variations and leads to a change in medication.

• The diagnosis of an exacerbation relies exclusively on the clinical presentation of the patient complaining of an acute change of symptoms (baseline dyspnea, cough, and/or sputum production) that is beyond normal day-to-day variation.

Causes

Life-Threatening Causes

Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.

• Arrhythmia
• Congestive heart failure
• Pleural effusion
• Pneumonia
• Pneumothorax
• Pulmonary embolism

Common Causes

• Respiratory tract infections (~½)
• Unknown (~⅓)
• Air pollutants

Treatment Setting and Severity

COPD Exacerbation ❑ Cough ↑ ❑ Dyspnea ↑ ❑ Sputum ↑
		1. Oxygen Supplement ❑ Pulse oximetry (maintain SaO2 ≥88—92%) ❑ Arterial blood gas (if acute or acute-on-chronic respiratory failure is suspected)
		2. Indications for ICU Admission ❑ Hemodynamic instability ❑ Changes in mental status (confusion, lethargy, coma) ❑ Severe dyspnea that responds inadequately to initial emergency therapy ❑ Worsening hypoxemia (PaO2 <40 mm Hg) and/or respiratory acidosis (pH <7.25)
				2a. Indications for Noninvasive Mechanical Ventilation ❑ Respiratory acidosis (arterial pH < 7.35 or PaCO2 >45 mm Hg) ❑ Severe dyspnea with sings of respiratory muscle fatigue ❑ Increased work of breathing 2b. Indications for Invasive Mechanical Ventilation ❑ Diminished consciousness, psychomotor agitation inadequately controlled by sedation ❑ Severe hemodynamic instability without response to fluids and vasoactive drugs ❑ Respiratory pauses with loss of consciousness or gasping for air ❑ Life-threatening hypoxemia in patients unable to tolerate NIV ❑ Persistent inability to remove respiratory secretions ❑ Heart rate <50/min with loss of alertness ❑ Severe ventricular arrhythmias ❑ Respiratory or cardiac arrest ❑ Failure of initial trial of NIV ❑ Massive aspiration
		3. Indications for Hospitalization ❑ Marked increase in intensity of symptoms (eg, sudden development of resting dyspnea) ❑ Presence of serious comorbidities (eg, heart failure or newly occurring arrhythmias) ❑ Failure of an exacerbation to respond to initial medical management ❑ Onset of new physical signs (eg, cyanosis, peripheral edema) ❑ Severe underlying COPD (GOLD 3—4 categories) ❑ Frequent exacerbations (≥2 events per year) ❑ Insufficient home support ❑ Older age (>65 years) 4. Assessment of Severity of Exacerbation ❑ Sputum purulence ❑ ECG (identify coexisting cardiac problems) ❑ Chest radiograph (exclude alternative diagnoses) ❑ Whole-blood count (identify polycythemia, anemia, or leukocytosis) ❑ Electrolytes and glucose (identify electrolyte disturbances or hyperglycemia)
						Severe Exacerbation ❑ Consider inpatient management ❑ Assess symptoms, ABG, and CXR ❑ Monitor fluid balance and nutrition ❑ Identify and treat associated conditions ❑ Consider subcutaneous heparin or LMWH ❑ Controlled oxygen therapy (use NIV if indicated) ❑ Antibiotics (if ↑ sputum purulence or ⊕ bacterial infection) ❑ Corticosteroids ❑ Bronchodilators ▸ Increase doses/frequency of short-acting bronchodilators ▸ Combine short-acting β2-agonists and anticholinergics ▸ Use spacers or air-driven nebulizers Moderate Exacerbation ❑ Consider outpatient management ❑ Require a short course of antibiotics or oral corticosteroids Mild Exacerbation ❑ Consider outpatient management ❑ Require change of inhaled treatment by the patient

Do's

Assessment

• The presence of purulent sputum during an exacerbation can be sufficient indication for starting empirical antibiotic treatment.

Treatment

Treatment Setting

• When a patient comes to the ED, the first actions are to provide controlled oxygen therapy and to determine whether the exacerbation is life-threatening. If so, the patient should be admitted to the ICU immediately.

Short-Acting Bronchodilators

• Short-acting inhaled β2-agonists with or without short-acting anticholinergics are usually the preferred bronchodilators for treatment of an exacerbation.

• A systematic review found no significant differences in FEV₁ between MDI and nebulizers, although the latter can be more convenient for sicker or frail patients.

• Intravenous methylxanthines (theophylline or aminophylline) are only to be used in selected cases when there is insufficient response to short-acting bronchodilators.

Corticosteroids

• Systemic corticosteroids in COPD exacerbations shorten recovery time, improve FEV₁ and Pa_O2, and reduce the risk of early relapse, treatment failure, and length of hospital stay.

Antibiotics

• Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis are the most common bacterial pathogens involved in an exacerbation. However, the choice of the antibiotic should be based on the local bacterial resistance pattern.

• Empirical coverage of Pseudomonas aeruginosa in GOLD 3 and GOLD 4 patients is important.

• Procalcitonin may be of value in the decision to use antibiotics.

Adjunct Therapies

• An appropriate fluid balance with special attention to the administration of diuretics, anticoagulants, treatment of comorbidities, and nutritional aspects should be considered.

• Healthcare providers should strongly enforce stringent measures against active cigarette smoking.

Respiratory Support

• Once oxygen is started, arterial blood gases should be checked 30 to 60 minutes later to ensure satisfactory oxygenation without carbon dioxide retention or acidosis.

• Venturi masks offer more accurate and controlled delivery of oxygen than do nasal prongs but are less likely to be tolerated by the patient.

• Noninvasive mechanical ventilation improves respiratory acidosis and decreases respiratory rate, severity of breathlessness, complications such as ventilator-associated pneumonia, length of hospital stay, mortality, and intubation rates.

Hospital Discharge and Follow-up

• In the hospital prior to discharge, patients should start long-acting bronchodilators, either anticholinergics and/or β2-agonists with or without inhaled corticosteroids.

• For patients who are hypoxemic during an exacerbation, arterial blood gases and/or pulse oximetry should be evaluated prior to hospital discharge and in the following 3 months. If the patient remains hypoxemic, long-term supplemental oxygen therapy may be required.

Prevention of COPD Exacerbations

• Smoking cessation, influenza and pneumococcal vaccines, knowledge of current therapy including inhaler technique, and treatment with long-acting inhaled bronchodilators, with or without inhaled corticosteroids, and phosphodiesterase-4 inhibitors are all therapies that reduce the number of exacerbations and hospitalizations.

• Early outpatient pulmonary rehabilitation after hospitalization for an exacerbation is safe and results in clinically significant improvements in exercise capacity and health status at 3 months.

Don'ts

Assessment

• Spirometry is not recommended during an exacerbation because it can be difficult to perform and measurements are not accurate enough.