Wednesday, December 23, 2009
Portacath Insertion Technique
There's an article in the British Journal of Surgery this month comparing two techniques of portacath insertion; the Seldinger technique vs. the venous cutdown. Portacaths are the little subcutaneous thingies that are used for chemotherapy infusions. Instead of having all your arm veins ravaged by the toxic chemicals of adjuvant chemotherapy, one can choose to have a port placed, thereby facilitating access to one of the main central veins.
Traditionally portacaths are placed as an outpatient surgical procedure using some IV sedation and local anesthetic. The majority of them are placed using the Seldinger technique whereby you jam a big fat needle into either the internal jugular in the neck or under the clavicle and into the subclavian vein, slide a guidewire through the bore of the needle and then advance the catheter to the SVC over the wire. The catheter is then tunneled subcutaneously for a bit and hooked up to a port, usually situated somewhere on the upper chest wall.
I generally don't do mine that way. Most of the time (95%) I utilize the venous cutdown method. I make a small incision over the deltopectoral groove, dissect out the cephalic vein, make a venotomy, and directly insert the catheter into the vein. The rest follows as per the Seldinger technique. It takes me about 10-20 minutes, usually. I do it without an assistant. There's no need for a CXR afterwards in the PACU. It's an elegant procedure when all goes perfectly.
Why do I choose to cutdown? Well, anytime you start jabbing large bored needles into someone's neck or chest wall, you assume a certain amount of risk; specifically pneumothorax, hemothorax, accessing the artery rather than the vein, etc. Granted, these complications don't occur very often (1-3% risk is usually quoted), but a typical general surgeons accumulates enough numbers over a career that inevitably he/she will have to deal with them at some point.
The cutdown eliminates the possibility of a lot of these complications. I don't have to worry about pneumothoraces. I don't have to worry that the blood I draw back on my needle stick is maybe arterial blood rather than venous (is it too red???). And it doesn't take me any longer than the guys who do the Seldinger technique.
The article alluded to seems to suggest that the cutdown is an inferior technique. And it's a decent article---randomized controlled trial and all that jazz. The data, the science, seems to suggest that the cutdown isn't any safer and, furthermore, it takes longer to perform. So what do I do with that information? Do I change my technique, to better accomodate myself to the "best available evidence"? Am I making myself liable if one of my ports becomes infected or gets clogged after a few months?
I can do a subclavian stick. I put central lines in quite a bit for post op sick patients and as a favor for my medicine colleagues. I prefer the subclavian over the jugular. I'm not afraid of the procedure. I think I'm adept at the technique. But for an elective case on a patient who has enough to worry about (recent diagnosis of cancer, uncertainty of the side effects of the anticipated chemotherapy) I want to use the technique that completely eliminates the possibility that a major complication could occur. Science be damned...