04/0/25

Question 1

How do you calculate the physiological clearance of an IV substance?

Answer 1

• Clearance in ml/min is calculated using the formula (U x V)/P
• U = urine concentration in mg/ml
• V = urine production in ml/min
• P = plasma concentration in mg/ml

Question 2

What is produced by the different cells of the stomach?

Answer 2

• Parietal cells = gastric acid & intrinsic factor
• Chief cells = pepsinogen
• D-cells = somatostatin
• Foveolar cells = mucus

Question 3

What do the different letters of the central venous pressure waveform denote?

Answer 3

• ‘a’-wave corresponds to atrial contraction
• ‘c’-wave corresponds to right ventricular contraction and bulging the tricuspid valve into the right atrium
• ‘x’-descent corresponds to rapid atrial filling due to atrial relaxation
• ‘v’-wave corresponds with atrial filling against a closed tricuspid valve
• ‘y’-descent corresponds with opening of the tricuspid valve and rapid emptying of blood into right ventricle

Question 4

Where does the posterior interosseous nerve exit the antecubital fossa?

Answer 4

Between the 2 heads of the supinator muscle

Question 5

What is Wallace’s rule of 9s for burns and how much of body surface area does a patient’s palmar area correspond to?

Answer 5

• Wallace’s rule of 9s for body surface area: genitalia is 1%, head and neck 9%, arms 9% each, legs 18% each, trunk 36%
• A person’s palmar surface area corresponds to 1% of their body surface area

Question 6

• Is oxygen consumption increased or decreased in the first few hours after traumatic injury?
• What about catecholamines?

Answer 6

• Oxygen is decreased
• Catecholamines are increased

Question 7

What is the most common infection post-splenectomy?

Answer 7

Strep pneumoniae

Question 8

Is 5-flurouracil an antimetabolite?

Answer 8

Yes

Question 9

What is the barium swallow finding for achalasia?

Answer 9

• Rat’s tail/bird beak
• Hypertrophied, dilated oesophagus above the lower sphincter

Question 10

Which lymph nodes do the different areas of the penis drain to?

Answer 10

• Penile skin: superficial inguinal lymph nodes
• Glans penis: deep inguinal lymph nodes
• Erectile tissue: internal iliac lymph nodes

Question 11

Between which 2 layers are you most likely to find the inferior epigastric vessels?

Answer 11

Transversus abdominus muscle and peritoneum

Question 12

What type of necrosis follows stroke and what may be seen following resolution on CT?

Answer 12

• Liquefactive necrosis
• Cystic lesions seen on CT
• (not coagulative necrosis like in parenchymal organs as brain has higher lipid content that parenchymal organs)

Question 13

Where are the bulbourethral glands formed?

Answer 13

In the urogenital sinus

Question 14

What lymph nodes do the testes drain to?

Answer 14

• The para-aortic lymph nodes
• (testes form in abdomen and drag blood supply and drainage down with them)

Question 15

Which movements are the muscles of the rotator cuff responsible for?

Answer 15

• Supraspinatus (+deltoid): abduction
• Infraspinatus + teres minor: external rotation
• Subscapularis: internal rotation

Question 16

How dry you calculate how much local anaesthetic can be used in a patient?

Answer 16

• Max recommended dose is 200mg
• Until then use 3mg/kg

Question 17

What is the most common cause of osteomyelitis in sickle cell patients?

Answer 17

Salmonella

Question 18

From which artery does the uterine artery arise?

Answer 18

Internal iliac artery

Question 19

How do mycotic aneurysms arise?

Answer 19

• From infections of the arterial wall
• Most commonly following endocarditis

Question 20

What is the first line treatment of hypercalcaemic crisis?

Answer 20

IV fluids