Compications will be assessed for single sampling technique or combination of different techniques

Assessment of the incidence, timing, and nature of complications occurring during bronchoscopy, within the first 24 hours, and up to 30 days after the procedure, comparing patients undergoing bronchoscopy at the time of initial ILD diagnosis with those undergoing the procedure during disease follow-up. The analysis aims to evaluate whether the clinical context and stage of disease management influence the safety profile of bronchoscopic procedures in ILD patients.

Assessment of the incidence, timing, and type of complications occurring during bronchoscopy, within the first 24 hours, and up to 30 days after the procedure in patients undergoing endoscopic evaluation for suspected or confirmed acute exacerbation of interstitial lung disease (AE-ILD). This analysis aims to investigate the safety profile of bronchoscopy in the setting of acute respiratory deterioration, a clinical condition often associated with increased frailty and higher risk of adverse events.

Comparison of the incidence and type of bronchoscopy-related complications between patients with non-exacerbated fibrotic ILDs and those with non-fibrotic ILDs, in order to evaluate whether the underlying radiological and pathological pattern of interstitial lung disease may influence the safety profile of endoscopic procedures.

Comparison of the incidence and severity of complications according to the specific bronchoscopic sampling technique performed, in order to evaluate the safety profile associated with each individual diagnostic procedure. Severity of complications will be assessed using The Common Terminology Criteria for Adverse Events (CTCAE) v6.0 (MedDRA 28.0).

Evaluation of the incidence and type of bronchoscopy-related complications according to the modality of respiratory support administered during the procedure, including low-flow oxygen therapy, high-flow nasal cannulas, Venturi mask, non-invasive ventilation, and invasive mechanical ventilation, as well as according to the type of sedation or anaesthesia employed, including conscious sedation, deep sedation, and general anaesthesia. This analysis aims to investigate the potential impact of ventilatory support and sedation strategies on procedural safety in patients with ILD.

Comparison of the overall rate of bronchoscopy-related complications between patients younger than 80 years and those aged 80 years or older, in order to assess the impact of advanced age on the safety of endoscopic procedures in ILD patients.

Comparison of the incidence of bronchoscopy-related complications between patients with interstitial lung disease (ILD) with chronic respiratory failure and those without chronic respiratory failure, in order to evaluate whether the presence of long-standing ventilatory impairment is associated with an increased procedural risk and a different safety profile of endoscopic techniques.

Comparison of the incidence of bronchoscopy-related complications between patients with interstitial lung disease stratified according to forced vital capacity (FVC), comparing those with FVC <80% of the predicted value versus those with FVC ≥80%, in order to assess whether the degree of ventilatory functional impairment is associated with differences in procedural safety.

Assessment of the incidence, timing, and nature of complications occurring during bronchoscopy when performed for therapeutic purposes in patients with interstitial lung disease, in order to characterize the safety profile of interventional endoscopic procedures in this specific clinical setting.

Evaluation of the need for escalation of respiratory support following bronchoscopy in patients with interstitial lung disease, including progression from baseline oxygen supplementation or ventilatory assistance to more intensive modalities.

Evaluation of the diagnostic yield of bronchoscopy in patients with interstitial lung disease, defined as the proportion of cases in which the procedure leads to a definitive diagnosis, either confirming a specific ILD subtype or identifying alternative clinically relevant conditions such as lower respiratory tract infection or malignancy. This outcome aims to quantify the overall diagnostic effectiveness of bronchoscopic evaluation in this patient population.

Comparison of the incidence of bronchoscopy-related complications between patients with interstitial lung disease stratified according to functional performance status, specifically between those with an Eastern Cooperative Oncology Group Performance Status (ECOG-PS) <2 and those with ECOG-PS ≥2, in order to assess whether a poorer baseline functional status is associated with an increased procedural risk and a different safety profile of bronchoscopy.

The Eastern Cooperative Oncology Group Performance Status (ECOG-PS) is a standardized clinical scale used to assess a patient's functional status, level of independence, and ability to perform activities of daily living. It is widely employed in cancer clinical practice and research to evaluate prognosis, treatment eligibility, tolerance to systemic therapy, and overall disease burden.

The ECOG-PS scale ranges from 0 to 5, with increasing scores indicating progressive functional impairment.

Assessment of hospitalization rate following bronchoscopy in patients with interstitial lung disease, in order to evaluate short-term post-procedural clinical outcomes and overall safety of the endoscopic procedure in this population.

Assessment of the main clinical, demographic, functional, radiological, and procedural characteristics associated with the occurrence of bronchoscopy-related complications in patients with interstitial lung disease through univariate and multivariate analysis, aiming to identify potential factors that may be linked to an increased risk of adverse events.

Assessment of 30-days mortality rate following bronchoscopy in patients with interstitial lung disease, in order to evaluate short-term post-procedural clinical outcomes and overall safety of the endoscopic procedure in this population.