CSFA Surgical Anatomy and Physiology 2 — Questions and Answers
Question 1: Which layer of the abdominal wall is avascular and serves as a surgical landmark during laparotomy closures?
- External oblique fascia
- Scarpa's fascia (Correct answer)
- Camper's fascia
- Transversalis fascia
Correct answer: Scarpa's fascia
Scarpa's fascia is the deep membranous layer of the superficial fascia that is relatively avascular and is often reapproximated during closure.
Question 2: During a right hemicolectomy, which structure is at greatest risk of injury at the hepatic flexure?
- Superior mesenteric artery
- Right ureter
- Duodenum (Correct answer)
- Common bile duct
Correct answer: Duodenum
The duodenum lies in close proximity to the hepatic flexure and is at risk during mobilization of the right colon.
Question 3: The ansa cervicalis nerve supplies which group of muscles relevant to anterior neck dissection?
- Sternocleidomastoid and trapezius
- Infrahyoid strap muscles (Correct answer)
- Scalene muscles
- Suprahyoid muscles
Correct answer: Infrahyoid strap muscles
The ansa cervicalis (C1–C3) innervates the infrahyoid strap muscles including the sternohyoid, sternothyroid, and omohyoid.
Question 4: Which physiologic mechanism primarily maintains mean arterial pressure when a patient transitions from supine to upright positioning on the operating table?
- Increased stroke volume
- Baroreceptor-mediated sympathetic vasoconstriction (Correct answer)
- Atrial natriuretic peptide release
- Parasympathetic withdrawal from the SA node
Correct answer: Baroreceptor-mediated sympathetic vasoconstriction
Baroreceptors in the carotid sinus and aortic arch detect pressure drops and trigger sympathetic vasoconstriction to maintain MAP.
Question 5: The fascial compartment containing the carotid artery, internal jugular vein, and vagus nerve is called the:
- Pretracheal fascia
- Prevertebral fascia
- Carotid sheath (Correct answer)
- Visceral fascia
Correct answer: Carotid sheath
The carotid sheath is a condensation of cervical fascia enclosing the carotid artery, internal jugular vein, and vagus nerve.
Question 6: During a low anterior resection, meticulous dissection of the total mesorectal excision (TME) plane stays within which embryologic tissue plane?
- Peritoneal reflection
- Waldeyer's fascia posteriorly and Denonvilliers' fascia anteriorly (Correct answer)
- Scarpa's fascia
- Endopelvic fascia laterally only
Correct answer: Waldeyer's fascia posteriorly and Denonvilliers' fascia anteriorly
TME requires sharp dissection within the avascular holy plane bounded posteriorly by Waldeyer's fascia and anteriorly by Denonvilliers' fascia.
Question 7: Which cardiac valve is located at the atrioventricular junction on the left side and has two leaflets?
- Tricuspid valve
- Pulmonic valve
- Aortic valve
- Mitral valve (Correct answer)
Correct answer: Mitral valve
The mitral (bicuspid) valve has two leaflets and guards the left atrioventricular orifice, distinguishing it from the three-leaflet tricuspid valve on the right.
CSFA Surgical Anatomy and Physiology 2
Which layer of the abdominal wall is avascular and serves as a surgical landmark during laparotomy closures?