Congenital Lobar Emphysemia

[umcRN, BSN, RN]

Can anyone explain the patho behind CLE?

I was taking care of a baby yesterday (1280 grams) who was prenatally dx with a right lung mass (supposedly a CPAM). When I arrived I got report that he had a "stable" night, last gas of the night was iffy but they would wait for rounds to discuss it, he had a few desats with cares to the 70's, was on moderately low pressures and peep with middle of the road rate and 30% FiO2. For other reasons I had to get my hands on him pretty early in my shift (his isolette was having a freak out, turned out he was COLD and also septic once I got that ball rolling for labs), but he continued to deteriorate resp-wise, going way up on vent settings and becoming very tenuous with handling, which I did not get in report, the fellow didn't want an xray for a while (assuming his issues were sepsis related) but finally decided we needed to do another, by the time we saw it the mass was almost double what it had been that morning...and we were having a very difficult time getting chest rise out of him. At that point she thought he must have had a CLE not a CPAM and wanted him on the HFOV immediately, initially she wanted to start with low Maps but she called the attending who said to start with higher maps (like 15-20). I was so busy with my patient that I didn't get a great explanation from her on why the attending requested the higher settings, I did some research last night but most of it is based on term and older children who have little to no symptoms and eventually have the affected lobe removed and are fine.

Can someone explain to me why changing to the HFOV and starting with higher Maps would enable us to decrease the size of the CLE at all? I understand a little why it got bigger with the increased pressures we were giving him (air trapping) but not quite understanding how the hfov would help...and he was put on so late in my shift that I didn't get to see what, if any differences it made. Thanks!