Medical Term of the Day: "Vagal Response"

When you've spent 8+ weeks in the hospital, I guess you start to pick up and use a lot of terms you'd never even heard of before.  I hadn't really given much thought to this, until I started having conversations with people outside the hospital and getting a lot of confused looks in response.  With that in mind, every now and again I'll pick a random medical term (that has relevance to Ayden) and explain it, to the best of my ability.  This is the first such post.

As I'm sure you know, Ayden has a history of really high heart rates (the SVTs).  There are several ways to deal with these episodes, including medication or cardiac ablation.  Those are preventative measures.  When preventative measures fail and an episode occurs, there is a third option: inducing a vagal response (or vagal reflex).  Basically, it is doing something specific to engage the vagus nerve, which then acts to lower the heart rate.

There are several different such responses.  One that has worked in stopping an Ayden SVT is the diving reflex.  Imagine jumping into a pool full of freezing water.  It would be a shock to your system, right?  Everything would kind of freeze for a moment or two and your heart rate would slow.  That's the vagal response.  Obviously, we couldn't dump Ayden in a bucket of cold water, but an ice bag to the face does the same thing (an adult with this problem could simply put his face in a sink full of cold water).  The doctors have used this particular vagal response on two occasions to stop an SVT.  It does the trick rather quickly.

A vagal response can also be caused by holding your breath and "bearing down" like you are trying to go #2.  Ayden has shown us his ability to do this over the last few days when he gets mad about having a breathing tube.  He bears down, holds his breath, and down goes his heart rate.  A little bit of bagging by his nurse brings him out of it and his heart rate comes right back up.  These little tantrums of his aren't really a big deal, but Allison and I will be glad when the breathing tube is gone so we don't have to deal with this anymore (we hope).

And this concludes our first lesson.

Class dismissed.