Patients with COPD/emphysema are at increased risk to develop malignancy and pulmonary infections and therefore frequently undergo diagnostic or therapeutic bronchoscopy. In addition, different interventional procedures such as valve/coil implantation or bronchial rheoplasty have been introduced. However, patients with COPD tend to have a lower mean and nadir transcutaneous oxygen saturation during bronchoscopy.

This investigator initiated, prospective, randomized controlled trial evaluates whether oxygen delivery using high flow nasal oxygen (HFNO) during sedation for bronchoscopy will improve oxygenation in patients with COPD compared to conventional oxygen by nasal cannula.

600 patients with COPD undergoing bronchoscopy will be randomised to either supplemental oxygen at 4 l/min or oxygen supplied using LM Flow 100 starting at a flow rate of 60 l/min and fraction of oxygen of 0.6. The primary end point is hypoxemia time (oxygen saturation<90%) during bronchoscopy.

The interim analysis included 399 patients with COPD, predominantly male (65%), with a mean age and BMI of 69±9 years and 25±5kg/m2 respectively. Hypoxemia time during bronchoscopy was significantly lower in the HFNO group (6.3%vs8.6%,p<0.0001). Additionally, the minimal measured oxygen saturation was lower in the control group (85%vs82%,p<0.0001). There was no difference between groups in both the average and highest value of transcutaneous measured carbon dioxide (44vs43mmHg,p0.27;54vs53,p=0.46).

Oxygen delivery, and thus oxygen saturation during bronchoscopy is superior using HFNO compared to conventional supplemental oxygen by nasal cannula. HFNO should be considered during bronchoscopy in COPD patients.