Physiological predictors of Hypoxic Challenge Testing (HCT) outcomes in Interstitial Lung Disease (ILD).

BACKGROUND: Pre-flight risk assessments are currently recommended for all Interstitial Lung Disease (ILD) patients. Hypoxic challenge testing (HCT) can inform regarding the need for supplemental in-flight oxygen but variables which might predict the outcome of HCT and thus guide referral for assessment, are unknown. METHODS: A retrospective analysis of ILD patients attending for HCT at three tertiary care ILD referral centres was undertaken to investigate the concordance between HCT and existing predictive equations for prediction of in-flight hypoxia. Physiological variables that might predict a hypoxaemic response to HCT were also explored with the aim of developing a practical pre-flight assessment algorithm for ILD patients. RESULTS: A total of 106 ILD patients (69 of whom (65%) had Idiopathic Pulmonary Fibrosis (IPF)) underwent HCT. Of these, 54 (51%) patients (of whom 37 (69%) had IPF) failed HCT and were recommended supplemental in-flight oxygen. Existing predictive equations were unable to accurately predict the outcome of HCT. ILD patients who failed HCT had significantly lower resting SpO2, baseline PaO2, reduced walking distance, FEV1, FVC and TLCO, but higher GAP index than those who passed HCT. CONCLUSIONS: TLCO >50% predicted and PaO2 >9.42 kPa were independent predictors for passing HCT. Using these discriminators, a novel, practical pre-flight algorithm for evaluation of ILD patients is proposed.

Idiopathic pulmonary fibrosis: a holistic approach to disease management in the antifibrotic age.

Idiopathic pulmonary fibrosis (IPF) is the most common cause of interstitial lung disease (ILD) and carries a worse prognosis than many cancers. Until recently, there were no active treatment options available for patients with IPF, meaning palliation or lung transplantation in selected patients were the only options. The management of IPF has changed dramatically over the last decade with the advent of two antifibrotic agents; pirfenidone and nintedanib. These new agents have been shown to reduce decline in lung function and pirfenidone has been shown to reduce mortality. The changing landscape of IPF diagnosis and management present a number of issues that may be encountered including management of side effects related to antifibrotic therapy. This article aims to give an overview of the holistic approach to the management of patients with IPF, including antifibrotic management, symptom management and the invaluable role of the ILD specialist nurse.