Errors in First Aid for the USMLE (2007): Gastrointestinal System

Pass usmle

Gastrointestinal

  1. P.280, Abdominal layers
    1. Not necessary, but I’m just begging you to change this image. In contrast to a typical cross-section on CT, this image is flipped over its axis. This means that with left body on right page, we are looking from head-to-toe and not toe-to-head (as in a CT) and the anterior abdominal wall is placed below the spine on the page instead of above (as in a CT). The simplest solution is to remove all the labels, flip the image across its horizontal axis (as opposed to rotation which would place the IVC and Aorta incorrectly), and then reapply the labels.
  2. P.281, Femoral triangle
    1. The Femoral nerve is not labeled correctly as a nerve. Instead, the “Femoral a.” and “Femoral v.” labels are both pointing to the Femoral nerve. The Femoral artery and Femoral vein are not labeled. This image is also missing the “Empty space and lymphatics” of the femoral triangle.
  3. P.282, Inguinal canal
    1. The “Deep inguinal ring” label is not labeling anything. I think a bar pointing to the ring should be added.
    2. The label “Medial umbilical ligaments” is pointing to one (of two) of the medial umbilical ligaments and (incorrectly) to the median umbilical ligament. The labeling should change appropriately.
    3. The labels “Deep inguinal ring” and “External inguinal ring” are not consistent with the next page, and I think the small changes to “Internal (deep) inguinal ring” and External (superficial) Inguinal ring” would clear up any confusion and bring it in line with the descriptions on the following page.
  4. P.284, Salivary secretion
    1. I think a fourth bullet point with “Lingual lipase begins TAG digestion; activated at low pH on reaching stomach” should be added. This offers a contrast to the activation and action of alpha-amylase.
  5. P.285, GI hormones
    1. I think it’s worth mentioning that Gastrin’s effects are inhibited by Somatostatin. According to Costanzo (BRS Phys), it is a pH of 3 (not 1.5 ) which is the checkpoint for the gastrin/acid-secretion feedback loop between the antrum and the body of the stomach.
      1. Vagal stimulation of gastric acid secretion is due to ACh (as listed on P.284), but no mention is made that vagal stimulation of gastrin secretion from G cells is due to Gastrin Releasing Peptide (GRP). Because this explains why anti-muscarinics do not prevent the secretion of gastrin, I think it should be mentioned.
    2. Cholecystokinin should include “(CCK)” since this abbreviation is not stated elsewhere and is used within the same row of the table. It is also worth mentioning that CCK potentiates Secretin’s effect on pancreatic HCO3- secretion.
    3. Secretin’s effect on increased bile production is not mentioned.
    4. I think it’s worth adding the second-messenger systems used by each hormone. Since Gs, Gi and Gq were previously covered (P.214) I think it’s helpful enough to list the following next to each hormone:
      1. Gastrin (Gq)
      2. CCK (Gq)
      3. Secretin (Gs)
      4. Somatostatin (Gi)
      5. GIP (Gs)
      6. VIP (Gs)
      7. NO (cGMP)
  6. P.286, Regulation of gastric acid secretion
    1. The pattern established by this figure is that each drug with a line towards a receptor is inhibitory for that receptor. This is not the for Misoprostol, which is a PG analog and stimulatory at the receptor. To avoid any confusion, I think that + and – signs are more appropriate here.
  7. P.294, Alcoholic hepatitis
    1. Changing the mnemonic from “You’re toASTed with alcoholic hepatitis” to “ToASTed, Sam GOT alcoholic hepatitis” helps you remember that SGOT is also known as AST (which is easy to forget).
  8. P.296, Primary sclerosing cholangitis
    1. I had no idea what an ERCP was, nor would I expect most other second-years to know it. If it’s going to be mentioned, I think it should be spelled out to “endoscopic retrograde cholangiopancreatogram (ERCP)”
  9. P.296, Reye’s syndrome
    1. In the way that acute pancreatitis is associated with gallstones and ethanol (for example), Reye’s is not associated “with viral infection … and salicyclates;” it is associated with the combination. It’s subtle but important. I think “and” should be changed to “treated with“.

Related Tags : Gastrointestinal System, errors, step 1, first aid


Related posts:

-Errors in First Aid for the USMLE (2007): Neurology
-Errors and Problems in High Yield Cell and Molecular Biology
-First Aid for the Basic Sciences, Organ Systems (First Aid Series)

Tags: , , ,

blog comments powered by Disqus