Week 3
A tiny person on an oscillating ventilator.
This post was written by Will.
Maggie is, for all intents and purposes, on life-support at the moment — not like a grown-up would be, because her organs are failing, but because they haven’t really started working yet. If she was still in utero she would probably be starting to take “practice breaths” relatively soon — breath-like motions pulling amniotic fluid into her still-developing lungs. By 32 weeks she would be consistently “practice-breathing”.
She didn’t get much of a chance to practice, but she has a lot of help. She has a breathing tube attached to an oscillating ventilator and at the moment she’s breathing in air that is 65% oxygen. Normal room air is 21%.
Last week she was getting above 90% O2 and was frequently at 100%. We seem to have found a stable place of steady, modest improvements, and we’re so happy and relieved and excited to have done so, at least for now.
Keeping this 02 level as low as possible is important because we need oxygen but it’s also toxic. High concentrations can damage her developing lungs. This damage can cause inflammation and scar tissue which can decrease her respiratory efficiency. The worst-case scenario here is a situation where the oxygen that she needs to breathe and survive right-now causes enough damage to her lungs that she can never breathe normal air.
We measure the effectiveness of her breathing by looking at the level of oxygen absorption in her blood through absorption spectrometry. She has two LEDs, one red, one infrared, on one side of her foot and some light-sensors on the other. Oxygenated blood absorbs different wavelengths of light from deoxygenated blood so we can compare the light emitted by the LEDs to the light that makes it to the sensors see how well her blood is absorbing oxygen.
We want this absorption rate to be above 88%. Whenever it drops below 88% an alarm goes off. Usually it goes back up pretty quickly on its own (because Maggie was squirming and shifting the tube around, or holding her breath or hiccuping or fighting the ventialtor and trying to breathe over it). Sometimes it doesn’t. If it doesn’t go back up on its own it’s called a “desaturation event” and the nurses take some actions to resolve it.
What kinds of actions? Increasing her O2 is the obvious one, though it can only go up to 100% and everyone is trying to keep is as low as possible so they always try other things first. Sometimes the solution is clear — she has squirmed herself into a weird position and is crushing the ventilator tube with her face. Sometimes it’s less obvious and the nurses just try to make her comfortable — shift her from one side to another, move her to her belly, or her back, suction out her mouth or breathing tube in case there has been any kind of mucus build-up. These are the best resolutions, and the most common.
There’s something incredible about this combination of high-tech sensing and hard numbers that trigger the alarm and the low-tech, human touch and attention and nurturing that they nurses use to resolve it. It’s a perfect synecdoche for the NICU as a whole. The place is filled with love and care and attention and gratitude. Maggie is strong, feisty, well-cared-for and deeply-loved. And so are we. Thank you.
