The Management of Interstitial Lung Disease in the ICU: A Comprehensive Review

Abstract

Interstitial lung disease (ILD) encompasses a diverse group of parenchymal lung diseases characterized by varying degrees of inflammation and/or fibrosis. Patients with ILD frequently require hospitalization, with many needing intensive care unit (ICU) admission, most often due to respiratory failure. The diagnosis and management of ILD in the ICU present unique challenges. Diagnosis primarily relies on chest CT imaging to identify fibrosis and inflammation. Acute exacerbations, whether in idiopathic pulmonary fibrosis (IPF) or non-IPF ILD, require careful evaluation of potential triggers and differential diagnoses. Bronchoalveolar lavage may provide valuable information, such as the identification of infections, but carries risks of complications. Biopsies, whether transbronchial or surgical, can also be informative but pose significant procedural risks. Corticosteroids are the cornerstone of treatment for acute exacerbations of IPF, with higher doses potentially benefiting non-IPF ILD. Additional immunosuppressive agents may be used in cases with evidence of inflammation. Oxygen supplementation, particularly with high-flow nasal cannula, is often employed to manage severe hypoxemia, while noninvasive ventilation can be useful for worsening hypoxemia and/or hypercapnia. When mechanical ventilation is used, it is recommended to target low tidal volumes to minimize lung injury; high PEEP may be less effective and even associated with increased mortality. Prone positioning can improve oxygenation in severely hypoxemic patients. In addition to ventilatory strategies, careful fluid management and addressing concomitant pulmonary hypertension are essential components of care. Extracorporeal membrane oxygenation is a high-risk intervention reserved for the most severe cases. Lung transplantation may be considered for end-stage ILD patients in the ICU, with outcomes dependent on the urgency of transplantation and the patient's overall condition. Managing ILD in the ICU requires a multidisciplinary approach, and despite recent advances, mortality remains high, emphasizing the need for continued research and individualized treatment strategies.

Keywords: acute exacerbation; interstitial lung disease; lung transplantation; mechanical ventilation; pulmonary fibrosis.

Figure 1

Chest CT images of a patient with fibrosis-predominant ILD showing honeycombing (image (B)), traction bronchiectasis (image (B)), and interstitial thickening. Image (A–C) show cross-sectional views of chest CT images of a patient with fibrosis-predominant ILD. Red circle shows traction bronchiectasis and blue circle shows honeycombing.

Figure 2

Chest CT images of a patient with inflammation-predominant ILD showing ground-glass opacities (image (C)). Image (A–C) show cross-sectional views of chest CT images of a patient with inflammation-predominant ILD. Red circle shows an area of ground-glass opacities.

Figure 3

Chest CT images of a patient with ILD at baseline and with an acute exacerbation (a few months after). The images (A,C,E) show the baseline disease involving interstitial thickening, reticulations, and mosaicism, while the images (B,D,F) show pronounced ground-glass opacities and increased interstitial infiltrates, indicative of an exacerbation when the patient was in the ICU.

Figure 4

The management of patients with ILD in the ICU. ILD (interstitial lung disease), ICU (intensive care unit), HFNC (high-flow nasal cannula), NIV (noninvasive ventilation), MV (mechanical ventilation), TV (tidal volume), and PEEP (positive end-expiratory pressure). The flowchart outlines a comprehensive approach to managing interstitial lung disease (ILD) in the ICU. Non-parenchymal causes must be ruled out. Acute exacerbations may be managed by using corticosteroids or other immunosuppressives, and careful fluid management, along with pulmonary hypertension assessment/management. For hypoxemia, various oxygenation strategies like HFNC and mechanical ventilation are utilized, tailored to patient needs. In severe cases, candidacy for lung transplantation is considered, potentially utilizing ECMO as a bridge to transplant.

Figure 5

Echocardiographic images from a patient with rapidly progressive interstitial lung disease admitted to the ICU. Images (A,B), taken at initial presentation, show a normal right ventricle (RV), left ventricle (LV), and right atrium (RA). Five days later, repeat imaging reveals acute right ventricular dilation in both the parasternal short-axis (image (C)) and apical 4-chamber (image (D)) views, consistent with rapid development of right ventricular failure in the setting of ILD exacerbation.