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All right, let's talk about closed loop, small bowel obstruction,

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obstruction, because this is where the magic happens.

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This is the drama.

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This is where, um, we need to make our diagnoses.

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So closed loop, small bowel obstruction.

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These are kind of the classic images from

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the 1992 paper showing this loop of small

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bowel that was either resulting from an

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adhesion here or twist in the small bowel.

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So it was always, you know, taught to us that they

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were two adjacent locations of small bowel obstruction.

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That's not necessarily true, but really the key here

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is the fact that there is a loop of small bowel or

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bowel that can't be drained retrograde with an NG tube

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and can't go prograde because of the obstruction.

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So as a result, this is just a loop of

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bowel, which is on its own and has no

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chance for decompression with an NG tube.

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This surgical definition is broader, and

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it should be, because that's what it is.

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It's, you know, it can be any reason

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why these loops can't be drained.

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So sometimes you actually have a long segment

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adhesion that will force off two different points

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of a loop of small bowel, so they don't have to be

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next to each other, I think is the key to that.

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And these small bowel obstructions are quite dangerous.

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So they really want us to think whether or not it's

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possible that it could be a small bowel obstruction,

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because that NG tube is not going to do a lot

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for you here.

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So this is our classic closed loop we just looked at.

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It has the mesenteric free fluid,

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very dilated loops of small bowel.

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Looks kind of like a sausage ring on coronal.

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I would say it looks like a loop of balloons, kind

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of bringing in with the strings here on the axial.

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I think that's a nice image there.

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Some people call this a radial array of bowel

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that's been described in the literature as a reason

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that you may think it's a closed loop obstruction.

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Frequently, there's convergence

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of these mesenteric vessels.

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You know that the veins are going to obstruct

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first, so there's going to be engorgement of

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veins with all that mesenteric fluid as a result

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of an outlet obstruction type of physiology.

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On the coronal plane here, you can see that

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there's going to be discordant enhancement.

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These are nice enhancing loops up here, whereas

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those loops stuck in the closed loop may be pretty

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homogeneous in attenuation with that mesenteric free

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fluid, lack of enhancement, early ischemic change.

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Here we have a double beak sign where you can see

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that it comes into a single location of obstruction.

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That's always fun to find if you can.

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On surgical image here, we're going to see that this

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is a loop of fecalized small bowel that had a

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double beak sign on the, um, surgical intervention.

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You can see that there was just a

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tight adhesion causing that loop of

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small bowel to be a closed loop indeed.

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Once they were able to resect that adhesion, the

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bowel was, uh, salvageable, which was quite good.

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So we want to get the patients to surgery.

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While there's still salvageability in these cases,

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again, that double beak sign with the loops of

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small bowel here in the right lower quadrant that

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have just that graying and mesenteric fluid, U-

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shaped and C-shaped loops that are very dilated.

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You should always suggest are the

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possibility of closed loop obstruction.

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Again, that focal mesenteric fluid adjacent to

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loops of small bowel will really bring the fact that

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that could be a closed loop obstruction as well.

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But why does it matter?

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I think the biggest thing now is the fact that

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a closed loop obstruction needs to be intervened

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on, and our surgeons have really gone towards

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quite an aggressive conservative management

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paradigm, meaning that they're trying to.

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Solve all small bowel obstructions without surgery

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whenever possible, because once you start doing more

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and more surgery, you get more and more adhesions.

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These patients come back with repeated small bowel.

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It's really a sad state.

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So whenever they can avoid surgery for small

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bowel obstructions, they definitely will.

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But in the case of closed loop

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obstruction, it wouldn't be safe.

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So we wouldn't want a patient to

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undergo the Gastrografin challenge.

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If you haven't heard of this or if you're

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not doing it in your hospital, I think

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everyone's kind of doing it at this point.

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This is a great option for patients who

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have a simple small bowel obstruction.

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Either the high-grade or low-grade we saw before,

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because Gastrografin is so osmotic that if you

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give it to the patients, they drink it, you give

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them a lot of IV fluids, it just brings in a

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lot of, um, fluid into the small bowel, and it

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basically pushes through the adhesions from the

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interior of the bowel and will lyse that adhesion.

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So what they do is they give

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Gastrografin down an NG tube.

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Probably elevate the head of the bed,

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because you do not want to aspirate Gastrografin.

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And that stuff can cause some heck of a pneumonitis.

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And then they'll take X-rays every

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eight hours until it gets to the colon.

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And then we've had really good results with

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this, but do not do the Gastrografin challenge

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in patients with closed loop obstructions or any

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signs of ischemia, because that would be dangerous.

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So that is why.

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Our ask is to determine who is safe

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for this Gastrografin challenge,

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who can be treated conservatively.

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So make sure that you're looking for closed loop

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obstructions, that you lower your threshold for them

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because you're better off overcalling a little bit

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on the closed loop obstruction than to miss them.

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And this is the Gastrografin challenge

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when it came all the way to the colon.

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And this patient's small bowel

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obstruction was relieved.