Do you check residual on J-Tube?

Young pt came in with G-J tube. Pmh: aspiration pneumonia, global developmental delay. Mother caring for the pt for 20+ years said J-tube for feeding, G-tube for meds. Doctor ordered to start feed at 25 ml/hr, increase to 50 after 4hr if tolerated. Also, check residual q4hr, if residual >300 hold feed for 1hr.
I thought I remembered not checking residual on j-tube from another pt, not sure. Unless the order was meant for G-tube, not specified, but it wouldn't have any residual considering only meds with some water goes in.. and they would be long gone after 4hrs. The point of j-tube is to prevent aspiration that ppl may get from g-tube, feed wouldnt be present in sm. intestine as it would in stomach, so pretty sure dont check residual there.
Confused.
I think you're thinking about checking placement. You don't need to check placement for that kind of tube because it's already in the stomach but you always need to check residual when they're on feeding to make sure they're absorbing the feeding, otherwise they could aspirate. Hopes this helps

The J tube is in the small intestines not the stomach. It is my understanding you do not check residuals with a true J tube because of its location. You also can't check placement with a J tube.. You can monitor the tubing left on the outside to ensure it has not changed but placement is confirmed once placed surgically. It is not like a NG or PEG..

If the doctors order clarified which tube feeding was supposed to be in, that would be helpful.

That's how I know it too. There's no point in aspirating a J-tube. I would have just clarified with the doctor. Maybe he's unaware that the patient was getting fed via J-tube or he forgot there were 2 tubes at all.