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Chronic Obstructive Pulmonary Disease, Emergency Medicine

Basics

Description

- 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 D - High symptom burden - mMRC ≥ 2 - High risk for exacerbations - FEV1 < 30% of predicted

- Pollutants - Changes to immunity - Increased airway inflammation

- Seasonal variations - More common and more severe in winter

- Intubation for airway control: - Clinical tiring - Altered mental status - Inability to comply with emergent therapy - Ineffective ventilation - CO2 narcosis

- Continuous ECG and pulse oximetry monitoring - Bronchodilator therapy - β-Agonists: - Anticholinergics: - Corticosteroids: - Anti-inflammatory effects - Reduce relapses - Methylprednisolone or prednisone

- 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

  • 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 lungChronic bronchitis: Airway inflammation without alveolar destructionReactive 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 mortalityFaster decline in lung functionWorse quality of lifeIncreased risk of hospitalization
  • Medical Research Council (mMRC) dyspnea scaleGrade 0: Only breathless with strenuous exerciseGrade 1: Short of breath when hurrying or walking up a slight hillGrade 2: Walk slower than people of same age due to dyspnea or have to stop for breath when walking on level groundGrade 3: Stop for breath after 100 m on level groundGrade 4: Too breathless to leave the house or breathless when dressing/undressing
  • GOLD guidelinesGroup ANo more than 1 exacerbation/yrFEV1 >80% predictedmMRC of 0 or 1Group BmMRC of 2 or moreFEV1 50-80% of predictedGroup CmMRC < 2≥2 exacerbations/yrFEV1 30-49% of predictedGroup DHigh symptom burdenmMRC ≥ 2High risk for exacerbationsFEV1 < 30% of predicted

Risk Factors

Genetics

О±1-Antitrypsin deficiency пїЅ

Etiology

  • Smoking is the overwhelming cause:COPD develops in 15% of smokers.
  • Air pollution
  • Airway hyper-responsiveness
  • О±1-Antitrypsin deficiency
  • Autoimmunity may play a role
  • Acute exacerbations:Viral infections>50% of exacerbations associated with recent cold symptomsDecreased immunity may make the host more susceptible to a COPD exacerbationRhinovirusRespiratory syncytial virus (RSV)Bacterial infectionsBacteria isolated in 40-60% of sputum during acute exacerbationMost common:Haemophilus influenzaeMoraxella catarrhalisStreptococcus pneumoniaeMore likely if:Increased dyspneaIncreased sputum volumePurulent sputumPollutantsChanges to immunityIncreased airway inflammationSeasonal variationsMore 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 dioxideAcidosisOxygenation
  • β-Natriuretic peptide:Differentiate between COPD and CHF
  • Sputum sample
  • Theophylline level as needed

Imaging

  • CXR:PneumothoraxPneumoniaCHFLobar 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: пїЅ

  • 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 requiredMay prevent intubationMay help resolve hypercarbia
  • Intubation for airway control:Clinical tiringAltered mental statusInability to comply with emergent therapyIneffective ventilationCO2 narcosis

Ed Treatment/Procedures

  • Continuous ECG and pulse oximetry monitoring
  • Bronchodilator therapy
  • β-Agonists:
  • Anticholinergics:
  • Corticosteroids:Anti-inflammatory effectsReduce relapsesMethylprednisolone or prednisone
  • Antibiotics:Fever, increased sputum production, and/or dyspneaMacrolides 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 patientsCO2 narcosis with oxygen saturation <90%Clinical tiring in the EDSevere acidosisConcomitant cardiac or pulmonary diseaseAcute coronary syndromeArrhythmiaCHFPulmonary embolism
  • Regular hospital bed:COPD patients with an additional pulmonary insult:PneumoniaLobar collapseIncreased work of breathing
  • Exercise intolerance
  • Failure to improve in ED
  • Failed outpatient treatment
  • 3 criteria can predict mortality at admission:Age >70 yrNumber 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 пїЅA, Barnes пїЅPJ. Update in chronic obstructive pulmonary disease 2011. Am J Respir Crit Care Med. 2012;185:1171-1176.
  • Celli пїЅBR. Update on management of COPD. Chest. 2008:133:1451-1462.
  • Cosio пїЅMG, Saeta пїЅM, Agusti пїЅA. Immunologic aspects of chronic obstructive pulmonary disease. N Engl J Med. 2009;360:2445-2454.
  • Macky пїЅAJ, Hurst пїЅJR. COPD exacerbation: Causes, prevention and treatment. Med Clin N Am. 2012;96;789-809.
  • Rosenberg пїЅSR, Kalhan пїЅR. An integrated approach to the medical treatment of chronic obstructive pulmonary disease. Med Clin N Am. 2012;96:811-826.
  • Sutherland пїЅER, Cherniack пїЅRM. 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)