Predictors of Severe Coughing and Its Impact on Bronchoalveolar Lavage and Transbronchial Lung Biopsy in Patients with Diffuse Lung Disease: Evaluation of Bronchoscopy Safety

<b>Background/Objectives</b>: Bronchoscopy is an invasive procedure, and patient coughing during the examination has been reported to cause significant distress. This study aimed to identify predictors of coughing severity and assess its impact on the procedure during bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBLB). <b>Methods</b>: We conducted a prospective study involving 119 consecutive patients with diffuse lung disease who underwent BAL and TBLB at Kyorin University Hospital from April 2019 to December 2023. Cough severity was scored on a scale of 0 to 3, with scores of 0-1 considered mild and 2-3 considered severe. Multivariate logistic regression analysis was performed to identify factors associated with severe coughing during the procedure. <b>Results</b>: Severe coughing was significantly associated with Grade 2 or higher bleeding (OR 6.230, 95% CI 2.220-17.400, <i>p</i> < 0.001), fewer TBLB specimens collected (OR 0.708, 95% CI 0.530-0.945, <i>p</i> = 0.019), and pre-procedural dyspnea (OR 2.560, 95% CI 1.110-5.870, <i>p</i> = 0.027). <b>Conclusions</b>: Severe coughing during bronchoscopy is associated with increased bleeding and reduced specimen collection. For patients with pre-procedural dyspnea, proactive cough management may improve procedural safety and outcomes.