Adventures with Ellie: Droppin’ P Waves...

Sounds like some sweet street slang, huh? Do people even use the phrase “street slang” anymore? Ugh – I’m so old! Anyhow, over the past day or so, Ellie has been bradycardic (meaning her heart rate has been pretty low). Her normal heart rate lately has been between 100-125. “Normal” is a fluid term for Ellie as each change in medication establishes a new baseline. When medications have changed from day to day, so has her baseline… so it’s a bit of a guessing game sometimes. Anyhow, her most recent baseline has been in the low hundreds. Before we were admitted, her resting heart rate at home was in the 160s. In the past day or two, Ellie has been dipping down to the 50s and 60s while she’s sleeping (bradycardia) and the nurses and cardiologists also noticed that her sinus rhythm on the monitors (the squiggly line of her heart beat) looked like it was dropping P waves. I know this is a little more medical jargon that normal… but stick with me. Below is a diagram of normal sinus rhythm from an EKG.

Diagram of normal sinus rhythm.

Ellie's missing the little bump w/ the P over it (occasionally).

Here is her monitor when she was bradycardic. The green # is her heart rate, white is her blood pressure, blue is her oxygen saturation (84% is perfectly fine for Ellie), and the yellow # is her breathing rate

The P wave shows atrial contraction. Followed by the contraction of the rest of the heart, then relaxation. When they noticed that Ellie’s monitors were showing that she wasn’t having P waves intermittently, they set her up for an EKG. Sure enough, the little booger is missing some P waves when her heart rate slows. This is called Second Degree SA block, type II. The cardiologist also said it’s called intermittent breakthrough junction rhythm. Whaaaaaa (in my best minion voice)? It’s not as scary as it sounds, I don’t think. But it’s time for another diagram – this time with adorable little faces for anatomical points. No idea why they’re playing basketball, unless they’re showing how the electrical impulse is “passed” from one part to another. Silly!

The little guy in the top left side of the picture is your Sinus Node (or SA node). He’s located in your right atrium and is your natural pacemaker in your heart. He’s really just a little bundle of neurons that starts the electrical impulse that keeps your heart on rhythm. The impulse then travels to the AV node (in the middle) and shoots down the ventricular septum and around the bottom walls of the heart to contract your ventricles and pump the blood out of them. Make sense? If not – I’m sorry… I don’t mean to make this clear as mud for ya.

Anyhow… the cardiologist said that in most babies Ellie’s age, their heart rates range from 100-150 beats per minute. This is how fast a typical SA node works. The AV node is also capable of producing its own contractions. Those contractions usually happen at a rate of 70-90 beats/minute. Finally, the branches of nerves that run along the bottom of the heart are also capable of initiating a contraction of the heart, but when just those are kicking in, the heart rate is between 40 and 60 beats/minute. So, this is where Ellie was the past few days. When P waves drop off the EKG, it indicates that the SA node is occasionally not firing and the contraction of the heart is initiated elsewhere. This isn’t detrimental, but it’s not a good thing. They’re hoping that by holding her heart meds (instead of slowly weaning her off), they can get the SA node to kick back up to full force and she’ll have a normal sinus rhythm again. Hoping for that, of course! They held meds through the night while she slept and are starting back on smaller doses today. I’ll bet her liver is jumping for joy at the idea of fewer meds. That little booger has had to metabolize a lot of stuff lately and it’d be nice to give that liver a break. It’d also be fabulous if holding these meds kicks the SA node back into gear. We haven’t talked with the electrocardio team (that exists, for real) to hear their plan, but this isn’t a huge deal, really. Sounds like a lot of medical mumbo jumbo, but it’s not crazy uncommon. I’m just hoping that her storms don’t resurface once she’s off of her heart meds. Really don’t feel like starting over with those again. But hey, we just take it a day at a time here.

Now – on to really good progress: trach collar trials! Yesterday in rounds, they suggested we start Ellie on trach collar trials. The first trial was yesterday morning and was 1 hour long. The second, yesterday afternoon and 2 hours. She has to successfully tolerate a 3-hour and 4-hour trial yet – hopefully both happen today. Then, we can think about an artificial nose. Let me explain the trach collar a bit. It’s essentially like taking an oxygen mask that’s pumping slightly oxygenated air plus cool mist and sitting it near Ellie’s trach. This allows her to do all the work on her own, but helps to control the amount of oxygen in the available air and also keeps her airway nice and moist (ick… worst word in the world… but really the only one that works for this). So when she breathes on the trach collar, it’s really not much different than breathing room air (with some mist). After each trial, they pull a little blood from Ellie’s PICC line and test the gases in her blood. Each time, she’s been able to maintain beautiful blood gas levels on her own – celebrations! If she does the same with the two trials today, we might be able to try an artificial nose this week. This is just a tiny barrel with a filter on the end of it to filter and dampen the air that she breathes (just like our noses do for us). If she’s able to maintain her saturation this way, and she tolerates this for the day time, we may be able to go home with just CPAP support at night. That would be amazing! C’mon Ellie… let’s do this!

Here are a few pictures of her during trach collar trials yesterday. She was full of smiles last night when Brandon got home from work.