Hyperbaric oxygen therapy and COPD

This is just a question to satisfy my own curiosity...our facility recently opened a HBOT center, and I got to wondering about this therapy and our patients with COPD. I did some looking online and some sites say COPD can be a contraindication while others say the therapy can be used specifically for COPD.

Is the contraindication more for those with more advanced COPD who have a lot of air-trapping? We have a lot of patients with both DM and COPD and those are the ones usually with the stubborn wounds. Just curious and trying to wrap my head around it :)

Thanks!