Acute Exacerbation of COPD (AECOPD)
AECOPD by GOLD = An event characterized by worsening dyspnea, cough, and/or sputum production over less than 14 days, which may be accompanied by tachypnea and/or tachycardia and is often associated with increased local and systemic inflammation caused by airway infection, pollution, or other insults.
Respiratory failure is usually due to a combination of diaphragmatic fatigue and bronchospasm.
Pathophysiology
1. Trigger → Airway inflammation
- ↑ Neutrophils, macrophages
- ↑ Cytokines (IL-6, TNF-α)
2. Airway changes
- Bronchospasm
- Mucus hypersecretion
- Edema
3. Consequences
- ↑ Airway resistance
- Dynamic hyperinflation
- Air trapping
4. Gas exchange
- V/Q mismatch → hypoxemia
- Hypoventilation → hypercapnia
- Severe → respiratory acidosis
Etiology
|
Cause |
Examples |
Notes |
|
Infections (70–80%) |
Viral: Influenza, RSV |
Most common |
|
Infection does not always means pneumonia |
Bacterial: H. influenzae, S. pneumoniae, Moraxella |
Purulent sputum |
|
Environmental |
Air pollution, smoking |
Major in India |
|
Cardiac causes |
HF, arrhythmia |
|
|
Others |
Non-adherence, sedatives |
ICU relevance |
Clinical Features
Symptoms
- 50-80 years old ,chronic smoker(older patient)
- ↑ Dyspnea (most important)
- ↑ Sputum volume
- ↑ Sputum purulence
- Cough, wheeze
- Hemoptysis?
- Chest discomfort?
- Fevers, night sweats, rigors.,wt loss?(T.B reactivation)
- Ankle edema(right ventricular dysfunction)
Signs
- Tachypnea, tachycardia
- Use of accessory muscles
- Prolonged expiration
- Cyanosis
- Altered sensorium → CO₂ narcosis
ROME Severity Classification of AECOPD (2021)
The ROME Proposal (Respiratory Symptoms, Oxygenation, Ventilation, and Exacerbation Severity) classifies AECOPD severity using objective clinical and physiological parameters rather than treatment location (outpatient vs hospital).
ROME Severity Assessment
|
Parameter |
Mild |
Moderate |
Severe |
|
Dyspnea (VAS 0–10) |
<5 |
≥5 |
≥5 |
|
Respiratory Rate |
<24/min |
≥24/min |
≥24/min |
|
Heart Rate |
<95/min |
≥95/min |
≥95/min |
|
SpO₂ |
≥92% (or baseline) |
<92% |
<92% |
|
CRP |
<10 mg/L |
≥10 mg/L |
≥10 mg/L |
|
ABG |
No hypercapnia/acidosis |
Hypercapnia without acidosis |
Hypercapnic respiratory acidosis |
|
Mental Status |
Normal |
Normal |
Altered consciousness may occur |
Investigations
WHEN COPD IS NOT PREVIOUSLY DIAGNOSED
You can still label as “suspected AECOPD” if:
- Typical history (smoker + chronic cough/dyspnea)
- Compatible clinical picture
Confirm COPD later with spirometry:Post-bronchodilator FEV₁/FVC < 0.7
1. ABG
- ABG/VBG doesn’t generally help diagnose AECOPD or differentiate it from other diagnoses.
- ABG/VBG is primarily helpful in a patient with altered mental status to evaluate for hypercapnic encephalopathy.
- Normal PCo2 is dangerous MEANS PATIENT IS FATIGUE
- COPD generally impairs CO2 clearance but shouldn’t cause profound hypoxemia. If the patient has escalating oxygen requirements, this suggests something else is going on (e.g., pneumonia, mucus plugging, pulmonary embolism)
2. Imaging
- CXR:Exclude pneumonia, pneumothorax, heart failure
|
Finding |
Emphysema |
Chronic Bronchitis |
|
Hyperinflation |
Marked |
Mild |
|
Hyperlucency |
Present |
Minimal |
|
Bullae |
Common |
Rare |
|
Vascular pruning |
Common |
Less prominent |
|
Bronchovascular markings |
Reduced |
Increased |
|
Heart size |
Vertical/narrow |
May be enlarged |
|
Diaphragm |
Flattened |
Mild flattening |
|
Increased Retrosternal Air Space(Hyperinflated lungs expand anteriorly.) | ||
- CT (if unclear diagnosis)
- Bedside echo(Suspected HF / cor pulmonale-routine not recommended)
3. Lab tests
- CBC → infection(Leukocytosis → bacterial trigger)
- CRP / Procalcitonin → bacterial trigger
- Electrolytes → esp. K⁺(β₂-AGONISTS → HYPOKALEMIA,Acidosis → ↑K⁺)
- ECG → arrhythmias,RV strain (S1Q3T3) → PE
4. Microbiology
- Sputum gram stain and culture are not helpful (unless there are concerns regarding the possibility of pneumonia or bronchiectasis).
- Viral PCR (e.g., COVID, influenza PRN).
Differential Diagnosis (MUST EXCLUDE)
|
Condition |
Clue |
|
Acute heart failure(HF commonly coexists with COPD) |
Pulmonary edema,pedal edema,BNP / NT-proBNP ↑ |
|
Pulmonary embolism |
Sudden dyspnea,Leg swelling / DVT signs,Chest pain (pleuritic),negative D-dimer may often be sufficient to exclude PE if still suspected do CT angiogram |
|
Pneumonia(very difficult to differentiate ) |
Fever, lobar consolidation(CXR),Focal crackles,Procal |
|
Pneumothorax |
Sudden deterioration,Silent chest,Chest pain (pleuritic),Absent lung markings |
|
Asthma exacerbation(very challenging ) |
Younger patient |
|
AEOHS |
|
|
Chronic opioids |
|
|
Bronchiectasis |
History and thoracic CT scans |
MANAGEMENT (GUIDELINE-BASED — GOLD / ERS / ATS)
1. OXYGEN THERAPY
- Target SpO₂: 88–92%
- Avoid over-oxygenation → CO₂ retention
Devices:
- Venturi mask (preferred)
- Nasal cannula (mild)
2. BRONCHODILATORS(Best combination → SABA + SAMA)
- SABA: Salbutamol(Albuterol)/LEVOSALBUTAMOL
- Nebulization (preferred in severe cases)
- Salbutamol—2.5–5 mg every 20 min × 3 doses
- Levosalbutamol-1.25mg every 20 min × 3 doses
- Then every 1–4 hr depending on response
- Duration of action : 4–6 hours
SAMA: Ipratropium bromide
- Blocks M3 receptors → inhibits vagal bronchoconstriction
- Duration of action : 6–8 hours
- Nebulization:-0.5 mg every 6–8 hr
- For patients on BiPAP or HFNC, bronchodilators should be nebulized and administered in-line through the device (without removing the patient from support).
MDI + Spacer (Equivalent to Nebulization)
|
Drug |
Dose |
|
Salbutamol MDI |
4–10 puffs (100 mcg/puff) |
|
Ipratropium MDI |
4–8 puffs (20 mcg/puff) |
|
Frequency |
Every 20 min for first hour, then every 2–4 h according to response |
LONG-ACTING BRONCHODILATORS (LABA / LAMA)
- NOT for acute relief
- Stop them(too breathless to take their home medications properly) and Restart before discharge
Used for maintenance, not acute phase
3. SYSTEMIC CORTICOSTEROIDS
- Prednisolone 40 mg PO once daily × 5 days
WHY ONLY 5 DAYS?
- Trials (e.g., REDUCE trial) showed:5 days = 10–14 days (same efficacy)
Benefits:
- ↓ Treatment failure
- ↓ Hospital stay
- ↑ FEV₁ recovery
If oral not possible:
- IV equivalent:
- Hydrocortisone 100 mg 6–8 hourly
- OR Methylprednisolone 40 mg/day
Switch to oral as soon as feasible
NO taper required (if ≤5–7 days)
ADVERSE EFFECTS -Short-term (relevant in AECOPD)
|
Effect |
Mechanism |
|
Hyperglycemia |
↑ gluconeogenesis |
|
Hypokalemia |
Mineralocorticoid effect |
|
Fluid retention |
Na⁺ retention |
|
Delirium / psychosis |
CNS effect |
|
Myopathy |
muscle catabolism |
|
Infection risk |
immunosuppression |
Nebulized budesonide – Not routinely Recommended,
could be a rational therapy for patients with mild COPD exacerbation plus contraindications to systemic steroids (e.g., brittle diabetes, history of severe steroid-induced psychosis).
4. ANTIBIOTICS
GOLD INDICATIONS: A. Anthonisen criteria (classic)
- All 3 symptoms present:
- Increased dyspnea
- Increased sputum volume
- Increased sputum purulence (MOST IMPORTANT)
OR
- Any 2 symptoms + one must be purulence
B. Severe exacerbation
- Mechanical ventilation (NIV or invasive)
- ICU admission(no need to have opacity on CXR),use narrow-spectrum antibiotics-Azithromycin/Doxycycline 5–7 days
C. Strong suspicion of bacterial infection
- Fever
- Leukocytosis
- Consolidation on imaging
WHEN NOT TO GIVE
- Mild exacerbation without purulence
- Clearly viral illness
- No change in sputum
Avoid overuse → resistance + adverse effects
5. Therapies NOT Routinely Recommended
|
Therapy |
Guideline Position |
|
Chest Physiotherapy |
Not routinely recommended; may be considered for large sputum burden or bronchiectasis. |
|
Mucolytics (N-acetylcysteine, carbocisteine) |
No routine role during acute exacerbation |
6. VENTILATORY SUPPORT
Non-invasive ventilation (NIV) — FIRST LINE
Indications:
- pH < 7.35
- PaCO₂ > 45
- Severe dyspnea/ tachypnea (respiratory rate >~30/min).
- Goal-diaphragmatic fatigue prevention.Pc02 normalisation is not the goal.
- Start at 10cm iPAP/5 cm ePAP
- maximum support level of around ~20cm iPAP/5 cm ePAP
- Try to achieve an adequate tidal volume and & minute ventilation.
- Can’t tolerate the BiPAP mask?—try sedation(Dexmedetomidine Best )IV haloperidol, droperidol, or olanzapine(serial VBG monitoring needed with sedation.)
- If that fails, then HFNC.The flow rate of HFNC should be maximized to the highest level the patient will tolerate (ideally at least 50-60 liters/minute flow) to wash out dead space.
- Severe tachypnea and air hunger— small divided doses of fentanyl to decrease RR to 12-24/min if respiratory rate >~30/min patient will fatigue (clue-normal or below normal Pco2) and its impending intubation
- For most patients, ~12-24 hours of Bipap support is adequate(HFNC can be continued indefinitely)
- >48 hours of BIPAP cause ulceration of the nose—consider intubation.
Invasive Mechanical Ventilation
Indications:
- NIV failure(high Pco2 is not always sign of NIV Failure)
- Severe acidosis (pH < 7.25)
- Altered mental status/Resp fatigue(Most important)
- not protecting their airway (e.g., gurgling secretions)
- Multiorgan failure (e.g., COPD plus cardiogenic/septic shock).
Ventilation Strategy (to avoid air trapping-AutoPEEP)
- Low RR with sedation(12-14/min)High inspiratory flow
- Long expiratory time
- Increasing the set PEEP slightly(70% of intrinsic PEEP)-usually 5-8 cm
- Permissive hypercapnia
- Bag these patients gently and slowly.(pneumothorax)
- Use a relatively large-size ETT(decrees resistance)
- Target pc02 close to the patient’s baseline value because Many COPD patients have chronic hypercapnic respiratory failure with chronic compensatory metabolic alkalosis. .In most cases, you won’t know the patient’s baseline. In this situation, targeting a slightly low pH (~7.25-7.35) will get you close to the patient’s baseline pCO2.
- Duration of ventilatory support-at least ~24 hours to allow diaphragmatic rest.Prophylactic extubation to HFNC or BiPAP reduces the risk of extubation.
Complications
- Respiratory failure
- Pneumothorax
- Arrhythmias
- Secondary infections
- Ventilator-associated pneumonia
DISCHARGE & SECONDARY PREVENTION
1. Pharmacological
- LABA + LAMA ± ICS
- Roflumilast (frequent exacerbators)
2. Non-pharmacological
- Smoking cessation
- Pulmonary rehab
- Vaccination:
- Influenza
- Pneumococcal