Basics
Description
- 3rd leading cause of death in US
- A disease characterized by airflow obstruction due to several processes:
- Emphysema: Irreversible alveolar destruction with loss of airway elastic recoil. Represents accelerated aging of the lung
- Chronic bronchitis: Airway inflammation without alveolar destruction
- Reactive airway disease: Reversible bronchospasm, mucous plugging, and mucosal edema
- COPD affects ~10% of the population and 50% of smokers.
- Increased incidence of hypertension, diabetes, heart failure, and cardiovascular disease in those with COPD
- Frequent exacerbations lead to:
- Greater mortality
- Faster decline in lung function
- Worse quality of life
- Increased risk of hospitalization
- Medical Research Council (mMRC) dyspnea scale
- Grade 0: Only breathless with strenuous exercise
- Grade 1: Short of breath when hurrying or walking up a slight hill
- Grade 2: Walk slower than people of same age due to dyspnea or have to stop for breath when walking on level ground
- Grade 3: Stop for breath after 100 m on level ground
- Grade 4: Too breathless to leave the house or breathless when dressing/undressing
- GOLD guidelines
- Group A
- No more than 1 exacerbation/yr
- FEV1 >80% predicted
- mMRC of 0 or 1
- Group B
- mMRC of 2 or more
- FEV1 50-80% of predicted
- Group C
- mMRC < 2
- ≥2 exacerbations/yr
- FEV1 30-49% of predicted
- Group D
- High symptom burden
- mMRC ≥ 2
- High risk for exacerbations
- FEV1 < 30% of predicted
Risk Factors
Genetics
α1-Antitrypsin deficiency �
Etiology
- Smoking is the overwhelming cause:
- COPD develops in 15% of smokers.
- Air pollution
- Airway hyper-responsiveness
- α1-Antitrypsin deficiency
- Autoimmunity may play a role
- Acute exacerbations:
- Viral infections
- >50% of exacerbations associated with recent cold symptoms
- Decreased immunity may make the host more susceptible to a COPD exacerbation
- Rhinovirus
- Respiratory syncytial virus (RSV)
- Bacterial infections
- Bacteria isolated in 40-60% of sputum during acute exacerbation
- Most common:
- Haemophilus influenzae
- Moraxella catarrhalis
- Streptococcus pneumoniae
- More likely if:
- Increased dyspnea
- Increased sputum volume
- Purulent sputum
- Pollutants
- Changes to immunity
- Increased airway inflammation
- Seasonal variations
- More common and more severe in winter
Diagnosis
Signs and Symptoms
History
- Dyspnea on exertion
- Cough
- Sputum production
- Fatigue
- Wheezing
- Orthopnea
- Altered mental status
Physical Exam
- Wheezing
- Retractions
- Decreased air movement
- Cyanosis
- Prolonged expiratory phase
- Barrel chest
- Lower-extremity edema
- Jugular venous distension
- S3 and S4 gallops
- Altered mental status secondary to carbon dioxide narcosis
Diagnosis Tests & Interpretation
Lab
- CBC:
- Elevated hematocrit may indicate chronic hypoxemia.
- Increased neutrophils and elevated WBC may indicate infection.
- Arterial blood gas:
- Retaining carbon dioxide
- Acidosis
- Oxygenation
- β-Natriuretic peptide:
- Differentiate between COPD and CHF
- Sputum sample
- Theophylline level as needed
Imaging
- CXR:
- Pneumothorax
- Pneumonia
- CHF
- Lobar collapse
- Chest CAT scan:
- When needed to evaluate for pulmonary embolus or further characterize disease
Diagnostic Procedures/Surgery
- Pulse oximetry
- ECG
- Pulmonary function tests
- Echocardiography:
- To diagnose left or right ventricular failure or strain
Differential Diagnosis
- Pneumothorax
- CHF
- Pneumonia
- Pulmonary embolus
- Upper airway obstruction
- Asthma
- Restrictive lung disease
- ARDS
- Pleural effusions
- Acute coronary syndrome
- Pericardial effusion
- Metabolic derangement
Treatment
Pre-Hospital
Supplemental oxygenation: �
- 100% via nonrebreather
- Do not withhold for fear of CO2 retention.
- Initiate nebulized bronchodilator therapy.
Initial Stabilization/Therapy
- Oxygen therapy:
- Maintain oxygen saturation >90-92%.
- Patients at risk for CO2 narcosis are those with slow respiratory rate.
- Monitor closely for ventilation suppression.
- Noninvasive ventilation:
- Treatment of choice in hypercapneic respiratory failure if ventilatory support required
- May prevent intubation
- May help resolve hypercarbia
- Intubation for airway control:
- Clinical tiring
- Altered mental status
- Inability to comply with emergent therapy
- Ineffective ventilation
- CO2 narcosis
Ed Treatment/Procedures
- Continuous ECG and pulse oximetry monitoring
- Bronchodilator therapy
- β-Agonists:
- Anticholinergics:
- Corticosteroids:
- Anti-inflammatory effects
- Reduce relapses
- Methylprednisolone or prednisone
- Antibiotics:
- Fever, increased sputum production, and/or dyspnea
- Macrolides also may have anti-inflammatory effects unrelated to their antibacterial role
- Methylxanthines
- Ventilator settings:
- Allow sufficient expiratory time to minimize air trapping and subsequent barotrauma.
- Permissive hypercapnia
Medication
- Albuterol: 2.5 mg nebulized q10-30min
- Azithromycin: 500 mg PO/IV once, then 250 mg/d PO for 4 days
- Ceftriaxone: 1 g IV q24h
- Ipratropium bromide: 0.5 mg nebulized q6h
- Levofloxacin: 500 mg PO/IV q24h
- Methylprednisolone: 125 mg IV q6h
- Prednisone: 40-60 (1-2 mg/kg) mg/d PO for 5 days
- Terbutaline: 0.25 mg SC q30min
First Line
- Albuterol
- Ipratropium bromide
- Prednisone or methylprednisolone
Follow-Up
Disposition
Admission Criteria
- ICU admission:
- Intubated patients
- CO2 narcosis with oxygen saturation <90%
- Clinical tiring in the ED
- Severe acidosis
- Concomitant cardiac or pulmonary disease
- Acute coronary syndrome
- Arrhythmia
- CHF
- Pulmonary embolism
- Regular hospital bed:
- COPD patients with an additional pulmonary insult:
- Pneumonia
- Lobar collapse
- Increased work of breathing
- Exercise intolerance
- Failure to improve in ED
- Failed outpatient treatment
- 3 criteria can predict mortality at admission:
- Age >70 yr
- Number of clinical signs of severity:
- Cyanosis, accessory muscle use, etc.
- Dyspnea at baseline
Discharge Criteria
- Mild flare
- Resolution in ED
- Ambulatory oxygen saturation >92%
Follow-Up Recommendations
- Smoking cessation
- Ensure vaccinations are up-to-date (influenza annually, pneumococcal at least once).
- Identify and avoid triggers (e.g., cold air, perfumes)
- Possible referral for lung volume reduction surgery
Pearls and Pitfalls
- Noninvasive positive pressure ventilation is the therapy of choice when optimal medical therapy is insufficient
- Nebulized steroids may be used more for acute exacerbation of COPD in the future.
- Patients with COPD are at increased risk for diabetes, hypertension, and cardiovascular disease.
- Consider routine influenza and pneumococcal vaccinations for those with COPD.
Additional Reading
- Agusti �A, Barnes �PJ. Update in chronic obstructive pulmonary disease 2011. Am J Respir Crit Care Med. 2012;185:1171-1176.
- Celli �BR. Update on management of COPD. Chest. 2008:133:1451-1462.
- Cosio �MG, Saeta �M, Agusti �A. Immunologic aspects of chronic obstructive pulmonary disease. N Engl J Med. 2009;360:2445-2454.
- Macky �AJ, Hurst �JR. COPD exacerbation: Causes, prevention and treatment. Med Clin N Am. 2012;96;789-809.
- Rosenberg �SR, Kalhan �R. An integrated approach to the medical treatment of chronic obstructive pulmonary disease. Med Clin N Am. 2012;96:811-826.
- Sutherland �ER, Cherniack �RM. Management of chronic obstructive pulmonary disease. NEJM. 2004;350:2689-2697.
See Also (Topic, Algorithm, Electronic Media Element)
- Asthma
- Congestive Heart Failure
- Dyspnea
- Pulmonary Embolism
Codes
ICD9
- 491.9 Unspecified chronic bronchitis
- 492.8 Other emphysema
- 496 Chronic airway obstruction, not elsewhere classified
- 493.20 Chronic obstructive asthma, unspecified
- 491.21 Obstructive chronic bronchitis with (acute) exacerbation
ICD10
- J42 Unspecified chronic bronchitis
- J43.9 Emphysema, unspecified
- J44.9 Chronic obstructive pulmonary disease, unspecified
- J44.1 Chronic obstructive pulmonary disease w (acute) exacerbation
SNOMED
- 13645005 Chronic obstructive lung disease (disorder)
- 87433001 Pulmonary emphysema (disorder)
- 63480004 Chronic bronchitis (disorder)
- 991000119106 Reactive airway disease (disorder)
- 442025000 Acute exacerbation of chronic asthmatic bronchitis (disorder)