Inspiratory Flow Rate Capability in Pulmonary Fibrosis Patients

The goal of this observational study is to learn about the inspiratory flow rate capability in patients with pulmonary fibrosis (IPF or PPF) when using inhaler devices with different resistances. The main questions it aims to answer are: What is the peak inspiratory flow rate (PIFR) that patients with pulmonary fibrosis can achieve through a medium-resistance inhaler device? What is the peak inspiratory flow rate (PIFR) that patients with pulmonary fibrosis can achieve through a high-resistance inhaler device? What is the inspiratory time (EIT) for each resistance level? Participants will use a portable device called In-Check™ DIAL G16, which simulates the resistance of different dry powder inhalers. Each participant will perform two breathing tests at a medium-resistance setting and two breathing tests at a high-resistance setting, with a 2-minute rest between settings. The device measures how fast air is breathed in and how long each breath lasts. This study will enroll 60 patients diagnosed with IPF or PPF at Shanghai Pulmonary Hospital. Participants will be involved for approximately 30 to 60 minutes, including training on how to use the device and the breathing tests. The study involves no drugs or invasive procedures.