An autumn pearl – Exchanging the blocked catheter

This segment will feature a unique pearl learned by a junior VIR staff during residency or fellowship to share with our community. This pearl is written by Dr. Joel Woodley-Cook from Scarborough Health Network.

Exchanging the blocked catheter (usually a gastrojejunostomy). The pull, cut and push technique.

It’s 3 PM on a Friday before a long weekend and the internist calls and says, “I think this patient’s GJ tube is blocked. The nurse keeps trying, but the semi-crushed tablet-apple sauce paste won’t go through. I need a stat change before this patient can go back to their nursing home. And they need to go back today or they will lose their bed at the nursing home and it will be all your fault”.

This exchange procedure typically goes smoothly but can go downhill quickly without a well established tract to re-enter. The technique described below is my go-to for a blocked catheter (usually GJ but sometimes nephrostomy).

I learned this technique from Dr. Martin Simons during my last month as a resident. This “pull, cut and push” technique is one I use often and is performed under fluoro (I sometimes bypass Step 1, but Step 1 does provide improved trackability of the catheter). This example will focus on a blocked GJ exchange:

1. Insert a 0.035” Amplatz through the hub or cut sidehole as far as it will go (obviously if it finds a sidehole, the procedure is likely nearly over and you can ignore steps 2+).
2. Retract the catheter under fluoro such that the pigtail lies within the 2nd segment of the duodenum.
3. Cut a side-hole close to the skin that is large enough to fit the tip of a second Amplatz but small enough such that the tip does not easily pop out. I usually insert the tip approximately 1 – 2 cm.
4. Advance the catheter under fluoro until the side hole is in the 2nd – 3rd segment of the duodenum.
5. Retract the tip of the wire that is in the side hole and voila, you have wire access into the duodenum.
6. Carefully remove the catheter under fluoro after releasing the pigtail as you normally would (don’t pull out your new exchange wire) and proceed with the exchange.