NBME 22 Superior rectal (NBME Answers)

NBME 22 Answers

nbme22/Block 1/Question#44 (reveal difficulty score)
A 52-year-old man with a history of alcoholic ...
Superior rectal 🔍 / 📺 / 🌳 / 📖
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submitted by ∗cathartic_medstu(37)

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Superior hemorrhoids blood, Inferior hemorrhoids thrombos. Always remember that.

-Goljan

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submitted by ∗bobson150(28)

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The wording of this question confused me. This is asking "which of these vessels is the high pressure system" right? So the high pressure superior rectal is causing increased pressure into the inferior rectal?

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welpdedelp Superior rectal comes from the inferior mesenteric vein which comes from the splenic vein --> portal veins Thus, this dude had cirrhosis so it would "back-up" into the superior rectal vein. FA 2018: p360 +16

nc1992 Superior rectal not superior mesenteric. Took me a minute +

hyperfukus ugh am i ever gonna get these right EVER +5

titanesxvi why not the inferior mesenteric, since the superior rectal drains there +2

thomasburton @titanesxvi think it is because question says direct which is why superior rectal +2

lilyo thomasburton, so are they asking what vessels do internal hemorrhoids directly drain into? The order is Superior rectal vein--> Inferior mesenteric vein--> portal vein. +

thomasburton Yes exactly, so they do eventually reach IMV but not 'directly' +

pg32 Also worded poorly because the varicosities are connections between the superior rectal and the middle/inferior rectal veins of the systemic circulation. So the blood could be in both the superior rectal vein and the middle/inferior rectal vein as that is what a varicosity is. +3

snripper You just gotta know indirect vs. direct hemorrhoids. In this case, it's an indirect hemorrhoid (superior rectal vein) because of the rectal bleeding. +

jesusisking @titanesxvi DrDoom explained it pretty well below: "Defining tributary: https://i.imgur.com/2zDxPbW.png Nice images make the term easier to recall. Smaller streams "pay tribute" to larger rivers (by flowing into them)" +

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submitted by ∗lilyo(94)

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I had the same question regarding this. I know that external hemorrhoids rarely bleed and internal hemorrhoids present as painless bleeding so in my mind I knew I was being asked about internal hemorrhoids. However, superior rectal--> inferior mesenteric vein--> portal vein, can anyone tell me why the answer was superior rectal and not inferior mesenteric?

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dubywow Because the wording sucks. It's a confusing way to word the question. I too was confused what direct tributaries was referring to and chose Inferior mesenteric because I suck and also because this question sucks. Really its asking where are the hemorrhoids? They are on/from the superior rectals even though those veins feed to Inferior mesenteric. +3

drdoom Defining tributary: https://i.imgur.com/2zDxPbW.png Nice images make the term easier to recall. Smaller streams "pay tribute" to larger rivers (by flowing into them). +5

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submitted by ∗surfacegomd(3)

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The qx asks for the direct tributaries following the vein that is producing the hemorrhoids, in this case internal hemorrhoids because they are painless.

(Amboss) Internal hemorrhoidal plexus -> superior rectal vein -> inferior mesenteric vein -> splenic vein -> portal vein -> ICV

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miajoseph the question doesn't mention pain, you should assume they're internal due to the patient's cirrhosis (portal system) +

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submitted by ∗imgdoc(183)

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This guy is having internal bleeding hemorrhoids secondary to cirrhosis of the liver. The path that internal hemorrhoids take is:

Superior rectal vein -> Inferior mesenteric vein -> splenic vein -> portal vein.

This cannot be superior mesenteric vein although it also drains to the portal vein by combining with the splenic vein. Back up of portal venous pressure is occurring here but it doesn't drain the anal canal which is where the bleeding is happening.

The inferior rectal vein hemorrhoid is called an external hemorrhoid and it usually causes painful bleeding below the dentate line. Internal hemorrhoids are present above the dentate line, and don't have somatic sensation so they are painless.

Lastly it is asking for where the "varicosities" or dilated veins are present specifically, and they are located in the superior rectal vein, not the inferior mesenteric vein.

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imgdoc Forgot to mention that the inferior rectal vein drains to IVC, and thats why there are no varicosities here. +

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