What is the emergency management for a patient with known idiopathic pulmonary fibrosis (or other fibrotic interstitial lung disease) presenting with a suspected acute exacerbation?

Emergency Management of Acute Exacerbation of Interstitial Lung Disease

High-dose corticosteroids are the primary pharmacological treatment for acute ILD exacerbation, with intravenous doses up to 1 gram per day reported in case series, despite the absence of controlled trial evidence. 1, 2, 3

Initial Diagnostic Confirmation

Before treating as an acute exacerbation, you must systematically exclude alternative causes of acute respiratory deterioration 2, 3:

• Rule out infection through procalcitonin (>0.5 ng/mL suggests bacterial infection), CRP, blood cultures, and consider bronchoalveolar lavage if diagnosis remains uncertain 3
• Rule out pulmonary embolism with CT pulmonary angiography or D-dimer if appropriate 2
• Rule out left heart failure with BNP/NT-proBNP and echocardiography 2
• Rule out cardiac arrhythmia with ECG and telemetry 2

The diagnosis requires acute worsening of dyspnea (typically <30 days), new ground-glass opacities on HRCT (particularly bilateral without lobar predominance), and worsening hypoxemia (≥10 mmHg decrease in oxygen levels) 3, 4.

Pharmacological Management

Corticosteroids (First-Line)

Administer high-dose corticosteroids immediately as first-line therapy 1, 2, 3:

• Intravenous methylprednisolone up to 1 gram per day has been reported in case series 1, 2
• The optimal dose, route, and duration cannot be specifically recommended based on current evidence, but this represents the standard of care 1, 2, 3
• This recommendation is based on anecdotal reports of benefit and the extremely high mortality (>50%) without treatment 1, 5

Adjunctive Immunosuppression

Consider intravenous cyclophosphamide as adjunctive immunosuppressive therapy 2, 3, 6:

• Other agents with purported success in historical cohorts include cyclosporine A and tacrolimus 6
• These are considered when corticosteroids alone appear insufficient 6

Antimicrobial Coverage

Administer broad-spectrum antibiotics if infection cannot be definitively ruled out 2, 3:

• Given the difficulty distinguishing infectious from non-infectious exacerbation, empiric antibiotics are often warranted 3
• Elevated procalcitonin supports bacterial infection and strengthens the indication for antibiotics 3

Anticoagulation

Consider low-molecular-weight heparin if thromboembolic disease is suspected, though routine use is not supported by sufficient data 2, 3.

Respiratory Support Strategy

Non-Invasive Ventilation First

Use non-invasive ventilation (NIV) as the first mode of ventilation for acute respiratory failure 2, 3:

• NIV is preferred over invasive mechanical ventilation given the poor outcomes with intubation 2, 3
• Provide supplemental oxygen to maintain adequate oxygenation 3

Avoid Invasive Mechanical Ventilation

Invasive mechanical ventilation is generally NOT recommended in patients with established IPF and acute respiratory failure due to extremely high associated mortality 1, 2, 3:

Exceptions where invasive ventilation may be considered 2, 3:

• Bridge to lung transplantation in eligible candidates
• First manifestation of ILD (diagnosis not yet established)
• Acute infection superimposed on ILD that may be reversible

This critical decision should ideally be discussed during stable clinic visits before an acute exacerbation occurs 3.

Urgent Transplant Evaluation

Immediately evaluate eligible patients for lung transplantation (typically age <65 years) 2, 3:

• Lung transplantation improves survival in advanced ILD 2
• Early assessment is crucial given the unpredictability of exacerbation events and poor prognosis 6
• Patients should have received information about transplantation early in their disease course 2

Supportive Care Measures

• Pulmonary rehabilitation should be considered during recovery phase to improve functional status and quality of life, though not feasible during acute phase 2, 3
• Treat gastroesophageal reflux disease as it may contribute to ILD progression 2
• Manage pulmonary hypertension in selected cases with severe elevation (mean PAP >35 mmHg) 1

Critical Pitfalls to Avoid

Delayed recognition and intervention leads to worse outcomes - early aggressive treatment is crucial 2:

• Do not delay corticosteroids while awaiting definitive exclusion of infection; treat both empirically if needed 2, 3
• Do not perform video-assisted surgical lung biopsy during acute exacerbation - it is too hazardous 3
• Avoid overuse of mechanical ventilation in advanced disease where it prolongs suffering without improving outcomes 2
• Do not accept "idiopathic" diagnosis without systematically excluding infectious triggers 7

Prognosis and Follow-Up

Short-term mortality exceeds 50% despite therapy, with poor long-term prognosis even in survivors 1, 6, 5, 4:

• Recovery may require several months 2
• Monitor for progression with symptoms assessment, pulmonary function tests, and chest imaging 2
• Reassess patients after exacerbations to determine if overall disease progression has occurred 1