Vascular Emergencies

Question 1

What is acute lower limb ischaemia?

Answer 1

Previously stable limb with sudden deterioration in arterial supply resulting in rest pain and/or other features of severe ischaemia of less than 2 weeks duration.

Question 2

What are the consequences of acute lower limb ischaemia?

Answer 2

Complete - extensive tissue necrosis within 6 hours of onset unless arterial circulation is restored. Needs assessment and prompt management to prevent amputation.

Question 3

What are the clinical features of acute arterial occlusion?

Answer 3

Intense spasm in distal arterial tree. Limb appears marble white. Mottling as skins fills with deoxygenated blood after spasm relaxes. If the mottling blanches, the limb is salvageable.

Question 4

What are the causes of acute lower limb ischaemia?

Answer 4

Embolism - AF, mural thrombosis, vegetations, proximal aneurysms, atherosclerotic plaque.
Thrombosis - atherosclerosis, popliteal aneurysm, graft closure, thrombotic conditions.
Dissection, trauma, external compression.

Question 5

What are the clinical features suggestive of acute embolism?

Answer 5

Sudden onset of symptoms, known embolic source, absence of previous claudication, normal pulses in other limb.

Question 6

What are the key points to cover in history of acute lower limb ischaemia?

Answer 6

Sudden onset symptoms? Exact duration of symptoms, 6 Ps. Underlying aetiology (cardiac disease, trauma, risk factors for atherosclerosis). Fitness for intervention.

Question 7

What are the 6 P’s of acute lower limb ischaemia?

Answer 7

Pain, pallor, perishingly cold, pulselessness, paraesthesia (early), paralysis (advanced ischaemia).

Question 8

Which investigations should be done in acute limb ischaemia?

Answer 8

Not many as narrow margin of time for them. Baseline bloods - G+S. ECG to check for AF. Senior help to advice on whether specific tests (duplex US/angiogram) are needed.

Question 9

How should acute limb ischaemia be managed?

Answer 9

Maximise tissue oxygenation with 15L 100% O2, IV heparin, appropriate analgesia, hypotension correction, treat cardiac condition.

Question 10

What is the definitive treatment of emboli in acute limb ischaemia?

Answer 10

Catheter embolectomy under LA or GA.

Question 11

What are the complications of revascularisation in acute limb ischaemia?

Answer 11

Sudden return of oxygenated blood to ischaemia muscles releases oxygen radicals -> cell injury and oedema. The oedema can lead to compartment syndrome and muscle necrosis.

Question 12

How is compartment syndrome managed?

Answer 12

Fasciotomy.

Question 13

What is the management of irreversible ischaemia?

Answer 13

Amputation.

Question 14

What is the sign for irreversible ischaemia of the limb?

Answer 14

Fixed mottling of the skin.

Question 15

What are the two types of aneurysm rupture?

Answer 15

Intraperitoneal and retroperitoneal.

Question 16

What is the survival rate of intraperitoneal ruptures of aneurysms and why?

Answer 16

Immediately fatal as the abdominal cavity has capacity for 23L of fluid and CO is 5L/min so quickly empties entire circulatory volume into abdomen.

Question 17

What is the survival rate of retroperitoneal aneurysm ruptures and why?

Answer 17

Survive to get to the hospital as the leak is contained but eventually it will rupture intraperitoneally, and become fatal.

Question 18

What are some presentations suspicious of AAA rupture?

Answer 18

Abdominal pain and vomiting, abdominal and back pain with collapse, renal colic in males >55 years.

Question 19

What is the classic triad of AAA rupture?

Answer 19

Abdominal/back pain, pulsatile mass, hypotension.

Question 20

How many patients present with the classic triad of AAA rupture?

Answer 20

Less than 1/3.

Question 21

What are the features on examination of AAA rupture?

Answer 21

Pale patient, unwell, cold, sweaty; weak and thready pulse, hypotension; tender pulsatile mass a few cm above umbilicus; bleeding causing peritoneal irritation so mimics acute abdomen.

Question 22

What are the differentials for AAA rupture?

Answer 22

MI with cardiogenic shock, massive pulmonary embolism, acute pancreatitis.

Question 23

What is the initial management of AAA rupture?

Answer 23

Oxygen 15L/min, IV access to take blood and give fluids to keep systolic BP 100mmHg, catheterise, contact vascular surgeon.

Question 24

What is the definitive treatment of ruptured AAA?

Answer 24

Surgical intervention - open repair or stent graft.

Question 25

What are the common outcomes of ruptured AAA?

Answer 25

50% die at home; 70% operable - 50% peri-operative mortality. Death from multi-organ failure.