Shunt Malfunctions
As I may have mentioned before, a Ventriculoperitoneal Shunt (VP Shunt) has three pieces (an excellent diagram is here):
1) Ventricular Catheter: The doctor drills a hole in the patients skull (usually behind one ear) and inserts a tube. The tube is perforated at the end with lots of little holes to allow fluid to drain away. The Ventricular catheter is then attached to a shunt valve and reservoir which is attached to the outside of the skull behind the ear.
2) Valve and Reservoir: In a way, your brain is like a plant - it needs just the right amount of fluid. If you give a plant too much water or too little, things do not go well. There are three sizes of valves that control how much fluid will drain: small, medium and large. Most infants do well with a medium valve although finding the right size is a matter of trial and error. Once through the valve, the fluid drains into a small plastic bubble (think the size of your typical bubble wrap). the reason for this is so that the doctors can stick a needle into the reservoir and draw out fluid whenever they need to analyze it for infections, etc.
3) Distal Catheter: This is the long tube that attaches to the other end of the reservoir and travels through the body to the abdomen where the fluid is drained and absorbed by the body just the same way a typical person's spinal fluid is absorbed after it leaves the spinal column.
There are two common and one slightly less common ways that shunts malfunction (keep in mind, I am not a doctor - this is all to the best of my knowledge).
A) The shunt comes apart. The tubes detach from the reservoir.
B) The Ventricular Catheter becomes clogged. Remember that infants are growing rapidly. To a certain extent, placing a perforated tube in the center of an infant's brain is like placing a wire birdcage in the middle of a garden and hoping none of the plants grow into it. Most commonly, the VC gets clogged with proteins. Sometimes, grey matter actually grows into it. Which sounds serious but (going back to the plant analogy) removing a clogged catheter and a small amount of grey matter is akin to cutting a stray vine in your garden. It doesn't hurt the plant and it grows just fine afterwards.
C) (less common) The Distal catheter starts draining someplace weird. The distal catheter (boy I must really be preoccupied with gardening today) is like a garden hose turned on at a low setting and left unattended. Most of the time, it just drains into the grass, every now and then the water goes where you wish it wouldn't.
It appears that Annabelle has the first case - a blocked Ventricular Catheter. So sometime this week the doctors will put her under, make a small incision where her shunt enters, pull out the clogged catheter and insert a new one.
This type of surgery is to be expected with VP shunts and while it should come as no surprise, it is discouraging to mom and dad and is sort of sending us "around the bend". But again, that is a subject for another post.
I hope the details here help you to pray more specifically for Annie-Lu-Who. We appreciate your prayers and support more than you know and will certainly keep you posted.
2 comments:
Bucket o' prayers, sweet people. Trust me when I say, she'll breeze through it, her parents? Not so much ;)
If it helps any, the only shunt revision Chunky Monkey had was when he was 3 months old. All these years later, he still has same one.
Hugs to all 3 of you!
Spreading the word for lots of prayers!
I hope you don't mind me posting her sweet face on my blog.
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