What is the approach to managing a patient with dyspnea in the emergency department, considering various underlying conditions such as chronic obstructive pulmonary disease (COPD) or asthma?

Emergency Department Approach to Dyspnea

Immediately assess vital signs with pulse oximetry and titrate oxygen to maintain SpO2 88-92% in patients at risk for hypercapnic respiratory failure (COPD, obesity, neuromuscular disease), while targeting 94-98% in all other patients. 1

Initial Assessment and Stabilization

Vital Signs and Oxygen Management

• Measure oxygen saturation immediately on arrival and document blood pressure, heart rate, respiratory rate, and temperature 1, 2
• For suspected COPD patients (age >50, long-term smoker, chronic breathlessness on minor exertion): target SpO2 88-92% using controlled oxygen delivery via Venturi mask at 28% or nasal cannula at 1-2 L/min 1
• Obtain arterial blood gas if SpO2 <90% or if respiratory acidosis suspected, and repeat within 60 minutes if initially acidotic or hypercapnic 3
• Avoid high-flow oxygen (>35%) in at-risk patients until blood gases are known, as 30% of COPD patients receive excessive oxygen leading to worsening hypercapnic respiratory failure and acidosis 1

Critical Warning: Oxygen Titration in Respiratory Acidosis

If respiratory acidosis is discovered due to excessive oxygen, do not discontinue oxygen abruptly—instead step down to 28% Venturi mask or 1-2 L/min nasal cannula, as oxygen levels fall within 1-2 minutes while CO2 takes much longer to correct 1

Diagnostic Workup

History Taking Priorities

• Document temporal onset (acute vs chronic), intensity of effort triggering dyspnea, and subjective description of breathlessness 4, 2
• Identify high-risk populations for hypercapnic failure: patients on long-term oxygen therapy, bronchiectasis with fixed obstruction, severe kyphoscoliosis/ankylosing spondylitis, morbid obesity (BMI >40), neuromuscular disorders with wheelchair use, home mechanical ventilation, or opioid/benzodiazepine overdose 1
• Review medications for psychoactive drugs (benzodiazepines, opioids, anticholinergics) that may contribute to respiratory symptoms 4

Physical Examination

• Assess respiratory distress signs: accessory muscle use, nasal flaring, tachypnea, paradoxical breathing, and fearful facial expression 4
• Perform lung auscultation (documented in 94.4% of cases) and heart auscultation (85.3% of cases) to identify wheezing, crackles, or cardiac abnormalities 2
• Cardiac examination should assess for murmurs, extra heart sounds, irregular rhythm, and peripheral edema 4

Diagnostic Testing

• Obtain chest radiograph on all patients to exclude pneumonia, pneumothorax, or pulmonary edema, as it changes management in 7-21% of hospitalized cases 3
• Perform 12-lead ECG if heart rate <60 or >110 bpm, or if cardiac symptoms present 3
• Complete blood count with basic metabolic panel should be obtained in most cases (86.9% standard practice) 2
• Point-of-care ultrasound (POCUS) can be used as an extension of physical examination when diagnostic imaging access is limited, though it requires trained professionals 4

Disease-Specific Management

COPD Exacerbation

• Administer nebulized bronchodilators immediately: salbutamol 2.5-5 mg and/or ipratropium bromide 0.25-0.5 mg, driven by compressed air if PaCO2 elevated 3
• Prescribe systemic corticosteroids: prednisolone 30 mg/day orally for 7-14 days 3
• Give antibiotics if ≥2 of the following: increased breathlessness, increased sputum volume, or purulent sputum (use amoxicillin or tetracycline first-line) 3
• Consider noninvasive ventilation (NIV) for patients with acute hypercapnic respiratory failure (pH <7.35) who fail initial therapy 3

Heart Failure

• Administer diuretics for volume overload, along with afterload reduction, beta-blockers, and aldosterone antagonists for systolic dysfunction 4
• Refer to heart failure specialists when patients develop NYHA class III-IV despite optimal therapy, severe cardiac dysfunction, or recurrent hospitalizations 4

Asthma

• Initiate or increase bronchodilators (β2-agonists and/or anticholinergics) for mild exacerbations 3
• Use systemic corticosteroids for severe exacerbations 3

Severity Assessment and Disposition

Indicators for Hospital Admission

• Loss of alertness or changes in mental status 1, 3
• Severe dyspnea or marked increase in dyspnea 1
• Respiratory acidosis (pH <7.35) or worsening hypercapnia 1, 3
• Inability to maintain SpO2 88-92% on low-flow oxygen 3
• Inadequate response to outpatient management 1
• High-risk comorbidities: pneumonia, cardiac arrhythmia, heart failure, diabetes, renal/liver failure 1
• Inability to eat, sleep, or care for oneself due to symptoms 1

ICU/Special Care Unit Admission Criteria

• Impending or actual respiratory failure 1
• Presence of other end-organ dysfunction (shock, renal, liver, or neurological disturbance) 1

Common Pitfalls to Avoid

• Never delay hospital evaluation if uncertainty exists about exacerbation severity 3
• Avoid sedatives which can worsen respiratory depression 3
• Do not use intravenous corticosteroids without clear indication when oral route is available 3
• Do not initiate pulmonary rehabilitation during hospitalization—wait until 3 weeks post-discharge as in-hospital initiation increases mortality 3
• Recognize that approximately 85% of chronic dyspnea cases are attributable to heart failure, myocardial ischemia, or COPD, with >30% being multifactorial 4