Biochemistry

Question 1

Describe the coeliac trunk

Answer 1

The first major branch of abdominal aorta originating at L1, almost immediately after entering abdominal cavity through diaphragm at T12.

Question 2

What are the coeliac trunk branches?

Answer 2

• Left gastric artery
• Splenic artery
• Common hepatic artery

Question 3

What are the risk factors for PVD?

Answer 3

• Age
• Male
• FH
• Smoking
• HTN
• Cholesterol
• Diabetes

Question 4

What is cerebrovascular disease?

Answer 4

• Atheroma
• Carotid artery - affects bifurcation most commonly
• Stroke, TIA, amaurosis (transient blindness in ipsilateral eye)

Question 5

What are aneurysms?

Answer 5

• Abnormal dilatation of artery
• > 50% of its normal transverse diameter
  Ectasia: dilation of up to 50%
  Arteriomegaly: generalised dilation

Question 6

What is the diameter of an AAA?

Answer 6

• Normal aorta <2.5cm
• Ectasia <3.5cm
• Small AAA <4.5cm
• Large AAA >5.5cm

Question 7

What are the risk factors for AAA?

Answer 7

• Males 4:1
• > 60s
• Hypertensive smokers
• FH of AAA

Question 8

What is aortic dissection?

Answer 8

There is a tear in the intima and blood enters between the media and intima causing more tearing and more blood to enter. Creates a false lumen.

Question 9

What are the causes of aortic dissection?

Answer 9

• HTN - stress and degenerative changes
• Connective tissue disease - Marfan’s
• Aneurysm - weakens wall
• Trauma
• Men 3:1
• 50-60 yrs

Question 10

What is the Stanford system classification for aortic dissection?

Answer 10

A - anywhere before left subclavian origin artery
- DeBakey I: starts ascending aorta and extends into arch and beyond
- DeBakey II: confined to ascending aorta
B - after LSA origin (treated medically)
- DeBakey III: starts in descending aorta

Question 11

What is the classifications of shock?

Answer 11

• Hypovolaemic: reduced intravascular volume
• Distributive: vasodilation and malperfusion
• Cardiogenic: intrinsic cardiac (pump) failure
• Obstructive: failure of circulatory flo

Question 12

What causes hypovolaemic shock?

Answer 12

• Haemorrhage
• Burns
• GI losses
• Dehydration e.g. polyuria (DKA)

Question 13

What causes distributive shock?

Answer 13

• SIRS related - sepsis, pancreatitis, trauma, burns
• Neurogenic - spinal cord injury
• Anaphylaxis

Question 14

What causes cardiogenic shock?

Answer 14

• Myocardial infarction/ischaemia
• Arrhythmia
• Acute valve pathology

Question 15

What are the causes of obstructive shock?

Answer 15

• Tension pneumothorax
• Pericardial tamponade
• PE