ABSITE Review Questions

Question 1

Which portion of the gastrointestinal tract is most responsible for the absorption of iron?.
A.  Stomach.
B.  Duodenum.
C.  Jejunum.
D.  Ileum.
E.  Colon.

Answer 1

B. Maximal absorption of iron occurs in the duodenum.B. Maximal absorption of iron occurs in the duodenum.

Question 2

Question 2.
Which portion of the gastrointestinal tract is most responsible for the absorption of bile acids and folate?.
A.  Stomach.
B.  Duodenum.
C.  Jejunum.
D.  Ileum.
E.  Colon.

Answer 2

D. Ileum.

Question 3

Question 3.
Which of the following parts of the duodenum are not considered to be retroperitoneal?.
A. 1 st proximal portion.
B. 2 nd (descending).
C. 3 rd (transverse).
D. All of the above are retroperitoneal.

Answer 3

A. The proximal portion of the first part of the duodenum is A. The proximal portion of the first part of the duodenum is intraperitoneal

Question 4

All of the following are true regarding small bowel anatomy and physiology except:.
A. Brunner’s glands produce an alkaline solution.
B. Enterochromaffin cells are involved in 5- hydroxytryptamine release, APUD , serotonin production.
C. Gastrin is produced by the parietal cells in the stomach and are innervated by the vagus.
D. The ileum is around 150 cm in length while the jejunum is about 100 cm.

Answer 4

C is false..
Gastrin is produced by antral G cells in the stomach and occasionally by pancreatic cells.
G cells are innvervated by the vagus..
Gastrin releasing peptide is released by the post-ganglionic fibers of the vagus during parasympathetic stimulation.
Bombesin also stimulates gastrin release.
Gastrin stimulates enterochromaffin-like cells to release histamine.
Gastrin also targets parietal cells by increasing the amount of histamine → the parietal cells therefore increase HCl secretion.

The other statements are true..
The jejunum is the maximum site of absorption, though the terminal ileum absorbs B12, bile acids, and folate..
Brunner’s glands produce an alkaline solution.
Enterochromaffin cells are involved in 5- hydroxytryptamine release, APUD , serotonin production.
The ileum is around 150 cm in length while the jejunum is about 100 cm.

Question 5

A 52 yo who has had a complicated history of multiple gastric and pancreatic procedures complains of loose stools that float. Which of the following is true of this condition?.
A. It can be caused by hyposecretion of gastric acid.
B. You should recommend higher intake of fats to compensate for the loss.
C. Is a known sequlae of extensive terminal ileum resection.
D. Pancrease is not effective.

Answer 5

C.  Steatorrhea is a known sequlae of terminal ileum resection.  Interruption of bile salt resorption interferes with micelle formation..
Gastric hyper (not hypo) secretion of acid increases intestinal motility and interferes with fat absorption.
Treatment involves controlling diarrhea (Lomotil), decrease PO intake (esp fats), Pancrease, and H2 blockers.

Question 6

Which of the following amino acids is a major metabolic fuel for enterocytes?.
A.  Alanine.
B.  Glycine.
C.  Leucine.
D.  Glutamine.

Answer 6

D. Glutamine is a major metabolic fuel for enterocytes and may play an important role in modulating the cytokine release from intestinal lymphocytes.

Question 7

You just performed a gastrectomy on a patient that had previously been in-house receiving pre-operative TPN @ 90 cc/hr. 4 hours post-op, the patient seems unusually somnolent, somewhat confused, and diaphoretic. His blood glucose returns as 35 mg/dL. Which of the following is likely to be true of this condition?.
A. It is unusual to see symptoms of hypoglycemia when serum glucose levels are above 25 mg/dL.
B. This was probably caused by stopping the TPN altogether during the operation.
C. TPN should not be administered intraoperatively as operative stress puts the patient on TPN at risk for hyperosmolar, nonketotic coma.
D. This is likely due to post-operative dumping syndrome.

Answer 7

B. Most likely, this patient is hypoglycemic because the TPN was not ran at all during the operation..
TPN associated hypoglycemia is caused by the sudden slowing of TPN administration, and is the most common cause of hypoglycemia other than excessive insulin administration.
Blood glucose levels less than 50 mg/dL can produce profound symptoms (dizziness, coma, arrhythmia, hypotension, diaphoresis).

It is usually safe to run TPN @ ~ 50 cc/ hr intraoperatively- it is unlikely that this will lead to hyperglycemia that will cause nonketotic coma.
10% dextrose can be given when TPN is to be stopped.
Weaning from tPN can usually be stopped when the infusions rates are 50 cc/hr or less.