How to manage a patient with a history of recurrent COVID-19 (Coronavirus Disease 2019) infections presenting with dyspnea as a single symptom and normal oxygenation levels?

Management of Dyspnea in Recurrent COVID-19 with Normal Oxygenation

Screen for respiratory muscle weakness and consider respiratory muscle testing, as dyspnea with normal oxygen saturation is a common presentation in recurrent COVID-19 infections and may reflect underlying respiratory muscle dysfunction rather than gas exchange abnormalities. 1

Understanding the Clinical Presentation

Your patient's presentation—dyspnea as an isolated symptom with SpO2 of 97%—is extremely common in COVID-19, particularly in recurrent infections:

• Dyspnea occurs in 38% of non-hospitalized COVID-19 patients despite normal oxygenation 1
• Over 71% of never-hospitalized COVID-19 patients report dyspnea at 79 days post-infection, even with preserved oxygen saturation 1
• The dyspnea often reflects respiratory muscle dysfunction rather than impaired gas exchange, explaining why oxygen saturation remains normal 1, 2

Immediate Assessment Priorities

Rule Out Life-Threatening Complications First

Before attributing symptoms to post-COVID respiratory muscle dysfunction, you must exclude:

• Thromboembolic events (pulmonary embolism is common in COVID-19) 3
• Myocarditis 3
• Bacterial superinfection (occurs in approximately 40% of viral respiratory infections requiring hospitalization) 3, 4

Consider empiric antibiotics (amoxicillin, azithromycin, or fluoroquinolones) if bacterial superinfection cannot be ruled out, as delaying antibiotics when bacterial coinfection is present significantly worsens outcomes 3, 4

Key Clinical Details to Obtain

• Symptom trajectory since the second infection: Is dyspnea worsening, stable, or improving? 3
• Functional capacity: Can the patient perform activities of daily living, or is there significant limitation? 5, 6
• Associated symptoms: Presence of fatigue (strongly associated with dyspnea), chest pain, palpitations, or cough 5, 6
• Previous COVID-19 severity: Patients with milder initial infections paradoxically may have more prominent dyspnea-fatigue phenotype 6

Diagnostic Workup

Essential Testing

Perform respiratory muscle performance testing as this is the most likely underlying mechanism:

• Maximal inspiratory pressure (PImax) and maximal expiratory pressure (MEPmax) to assess respiratory muscle strength 1
• Impulse oscillometry (IOS) to evaluate peripheral airway resistance 7
• Electrical Impedance Tomography (EIT) if available—shows regional ventilation inhomogeneity in 45% of patients with persistent dyspnea at 1 year, even when standard pulmonary function tests are normal 7

Additional Investigations

• Pulmonary function tests (spirometry, DLCO): May be normal in up to 42% of patients with dyspnea, but abnormalities are present in 58% 7, 8
• Six-minute walk test with continuous pulse oximetry: Desaturation during exertion (even if resting SpO2 is normal) independently predicts persistent dyspnea 5
• Echocardiography: Right ventricular dysfunction and elevated pulmonary artery pressures are associated with post-COVID dyspnea 5
• Chest CT: Abnormal imaging persists in 88% of previously hospitalized patients at 12 weeks 8

Management Strategy

Respiratory Muscle Training

Initiate respiratory muscle training interventions, as screening for respiratory muscle weakness and providing targeted interventions is crucial for COVID-19 patients with persistent dyspnea 1, 2:

• Inspiratory muscle training programs
• Breathing exercises focused on diaphragmatic strengthening
• Graduated exercise rehabilitation

Address the Dyspnea-Fatigue Phenotype

If pulmonary function tests are normal but dyspnea persists with prominent fatigue:

• This represents a distinct phenotype associated with milder infection, higher BMI, and reduced functional capacity despite normal PFTs 6
• Focus on comprehensive cardiopulmonary rehabilitation rather than assuming purely pulmonary pathology 6

Monitor for Progression

• At 2 months post-infection, 43% of patients still experience dyspnea 1, 2
• At 4-12 weeks, consider post-acute COVID syndrome; beyond 12 weeks, consider long COVID 3
• Persistent symptoms warrant ongoing follow-up and reassessment 2

Critical Pitfalls to Avoid

• Do not assume normal oxygen saturation excludes significant pathology: COVID-19 causes respiratory muscle dysfunction and regional ventilation inhomogeneity that manifest as dyspnea despite preserved gas exchange 1, 7
• Do not delay antibiotics if bacterial superinfection is possible: The 40% coinfection rate in viral respiratory infections makes empiric coverage reasonable when clinical suspicion exists 3, 4
• Do not overlook thromboembolic disease: Venous thromboembolism is common in COVID-19 and can present with isolated dyspnea 3, 4
• Do not rely solely on standard PFTs: Regional ventilation inhomogeneity detected by EIT may be the only objective finding in patients with persistent dyspnea 7

Prognosis and Expectations

SARS-CoV-2 infection causes inflammatory damage to lung parenchyma and creates an imbalance between breathing demands and respiratory muscle capacity, which may persist for months 2. The patient should understand that:

• Dyspnea may persist for 3-6 months or longer in 25-37% of cases 3
• Respiratory muscle performance can improve with targeted interventions 1
• Complete resolution may take 6-12 months, and some patients develop long COVID 3