Gastrointestinal

Question 1

What has caused this X-Ray presentation? Can you think of some possible causes of this?

Answer 1

Air in the abdominal cavity pushing up the diaphragm -> most likely perforated colon. Tumour growth leading to colon wall breach. Rapidly progressed Chron’s resulting in transmural weakness and rupture.

Question 2

What are the three bones that the muscles of the abdominal wall attach to?

Answer 2

Ribs, Pelvic brim, Spine (transverse processes)

Question 3

The external obliques run in which direction? What is this similar to?

Answer 3

Inferior and anterior
(Diagonally from the ribs down to the abdominal aponeurosis (Rectus Sheath)).

They run in the same direction as the external intercostals.

Question 4

What muscle is contained in the rectus sheath?

Answer 4

Rectus abdominis muscle

Question 5

What are the layers of the abdominal muscles from superficial to deep?

Answer 5

External Oblique

Internal Oblique

Transversalis Abdominis (Transverse Oblique)

Question 6

The internal obliques run in which direction?

Answer 6

Superior to anterior.

(upwards from the upper border of the rib below and forward to the inferior border of the rib above)

Question 7

What are the borders of the inguinal triangle (Hesselbach’s triangle)?

Answer 7

Medial: inferior epigastric vessels
Lateral: medial border of rectus abdominis muscle
Inferior: inguinal ligament

Question 8

Using the diagram, state anatomically where an indirect and a direct hernia would be found.

Answer 8

Direct:

Indirect:

Question 9

What does a COX-2 inhibitor do? When could it be used?

Answer 9

Inhibits enzyme COX-2 which is responsible for pain and inflammation.

Uses: manage peptic ulcers, osteoarthritis,

Question 10

What do the COX (cyclooxygenase) enzymes form?

Answer 10

Inflammatory mediators: prostaglandins, prostacyclins, thromboxanes

Question 11

How do NSAIDs cause ulceration?

Answer 11

Traditional NSAIDs are considered “nonselective” because they inhibit both COX-1 and COX-2. The inhibition of COX-2 by traditional NSAIDs accounts for the anti-inflammatory effect of the drugs while the inhibition of COX-1 can lead to NSAID toxicity and associated side effects (ulcers, prolonged bleedng time, kidney problems).