As old as I am and as many shunt replacements as I’ve had, I’ve never read the procedure. I know what they do but I didn’t know the medical terms for the parts of the body involved. Luckily it wasn’t something I wish I hadn’t read. Maybe the article was written to be read by patients. Surely it wasn’t a How To Do for doctors lol…but that would be terrifying.
I wonder how many writers give a character the same challenge they’ve faced in life? I know they write from experience, both personal and second hand, but how often does a writer write of an event they themselves experienced?
The article told me things I never thought much about. Like the length of the catheter placed in the ventricle. I know the ones that work best for me are short but I’ve never known how short. Now I do. And I know all of the medical and technical phrases and words to go with it. lol
Ventriculoperitoneal Shunt Operation
Position of the child is important to correctly implant the shunt. The head is turned sharply to the left, and the placement is a right occipital placement. The burr hole is placed approximately 4 cm up from the inion and 3-4 cm off the midline. This occipital placement allows a relatively straight shot into the body of the ventricle so that the shunt catheter is mostly within the ventricle. This trajectory avoids the risk of going to low, through the internal capsule, which can happen with shunt placement sites that are more lateral and inferior.
An adequate length of ventricular catheter needs to be selected to place the tip anterior to the foramen of Munroe, where there is less choroid plexus, this is to lessen the risk of occlusion. Generally, a 6 cm catheter is used in a small newborn, an 8 cm catheter in an older infant and young child, and a 10 cm catheter in a child 18 months or older. Perioperative antibiotics can be used, though definitive data showing that this is mandatory is lacking.
The shoulderblades should be raised to elevate the chest and neck, and allow for a straight passage of the shunt passer with no secondary incisions between the head and the abdomen. The abdominal incision is a horizontal incision, either just below the ribcage or just lateral to the umbilicus. Once the shunt is laid in position, the dura is opened with a pinpoint cautery to have just a big enough opening to allow the passage of the catheter (a large dural opening can allow CSF to flow around the shunt and cause a subcutaneous fluid collection). The ventricle is tapped using a rigid brain cannula and once obtaining a good flow of CSF the ventricular catheter is fed into the ventricle through this tract without a stylette.
Fluid should then be aspirated from the lower end of the shunt to insure that the valve system is opened and then it is placed into the peritoneal cavity. A large amount of tubing can be placed in the peritoneal cavity, and up to the full length has been used without any problems to allow for growth. We will typically place 15-20" of peritoneal catheter in at the time of the initial shunt placements.