Oxygen Saturation

She's already 18 days old (28 weeks and 2 days gestation in corrected age).

Starting yesterday she showed low oxygen saturation level (they call this "desat").
Usually they want to keep the O2 saturation level between 85% and 95%. For some reason or for no reason, Emilia would desaturate to somewhere around 50% from time to time. When this happens her limbs even turn blue - it's very scary.

She was doing very well at 25%-28% O2 concentration. Then the next day, her O2 concentration had to be boosted all the way up to 52% because her oxygen saturation level would sometimes drop to below 50%. Today she was back down to 30-35% concentration and was doing very well for hours, and then suddenly the saturation level started to plummet... and more O2 had to be blown into her lungs. She swings so much that her saturation level varies from 100% to 52% in a minute. I really don't know why there is such a large swing. She's not consistently desaturated. It just happens once in a while and when it happens, she can't quite recover from it.

Blowing in high concentration of oxygen in a preemie's lungs is not a good thing because it causes damage to the lungs. However because when the baby desats, we do need to boost up the O2 concentration in the air she breathes in. You see, it's a dilemma - I don't want the nurse to turn up the oxygen concentration to 50% just because she's showing a bit of desat. Turning up oxygen too high could damage her eyes and lungs so I want the nurse to give her a chance to push herself to higher saturation. But at the same time, it is also nerve wrecking to see the O2 saturation number drop and hear the monitor continuously beep on your baby. I wonder if this means she will have to be changed from HFO to the other ventilation mode. Yes, as all the NICU people say, one step foward and two steps backward...