FRCS General Surgery Viva Topics and Revision Notes

Stephen Brennan

• Publisher: CRC Press
• Year: 2017
• Print ISBN:
  9781846194986
• eBook ISBN:
  9781315346250
• Topic: Médecine
• Subtopic: Théorie, pratique et référence de la médecine

What are the indications for necrosectomy? How you perform an EUA for acute peri-anal sepsis? What do you understand by the term Early Goal-Directed Therapy (EGDT)? Remember: this is a consultant's exam, and giving a range of options is not good enough. You must tell the examiner what you as a consultant are going to do. The FRCS is a uniquely challenging prospect; highly detailed, wide-ranging and encompassing both theory and practice. Preparation for this exam can be very difficult, and resources tailored to it are scarce. As the consolidated notes of a recent successful candidate, this book is an essential resource when preparing for the viva. The wide variety of questions require you to define, diagnose or choose between treatment options, while MCQs and SBAs help you to objectively evaluate your progress - a unique supplement to your study plan. Answers provided are comprised of an invaluable combination of detailed written answers and lists that will remind you of key points and help you structure your preparation.

PART ONE

Vascular

• Abdominal aortic aneurysm (AAA)
• Varicose veins
• Acute and critical limb ischaemia
• Carotid disease
• Deep vein thrombosis

ABDOMINAL AORTIC ANEURYSM

What is an aneurysm?

An aneurysm is a permanent localised dilatation of an artery >50% diameter. The word comes from aneurusma, a Greek word meaning ‘to widen’.

Most common sites of arterial aneurysm formation (in descending order)

• Infra-renal abdominal aorta.
• Popliteal.
• Femoral.
• Carotid.

Risks for aneurysm formation

• Male (6 times more common than females).
• Smoking (8 times more common).
• Genetic.
• Marfan’s syndrome.
• Ehlers-Danlos syndrome Type 4.

NB: They are NOT related to ‘berry’ aneurysms.

Quoted figures

• 75% symptom-free when diagnosed (incidental).
• 75% mortality if AAA ruptures.
• 50% mortality if ruptured AAA reaches hospital.
• 25% AAA have synchronous lesion.

What is the evidence for elective repair at 5.5 cm?

UK Small Aneurysm Trial, Lancet 1998

• 1000 patients.
• 500 ultrasound surveillance (USS).
• 500 elective repair.
• 30-day mortality 5.8% (operative).
• No significant survival advantage at 6 years for AAA 4.0–5.5 cm.

What do you know about AAA screening?

The Highland Aneurysm Screening Project (HASP) based in Inverness demonstrated:

• screening the adult male population reduced the incidence of AAA rupture by 50%
• little benefit screening females.

AAA screening introduced in UK 2010

• Men aged 65 invited for one- off abdominal USS.

Supporting evidence: BJS (1994) showing that a single ultrasound scan at aged 65 will detect 90% AAA at risk of rupture.

What are the surveillance intervals?

UK AAA surveillance

5.5 cm	Elective repair
4.5–5.4 cm	Six-monthly scan
3.5–4.4 cm	Annual scan

What is EVAR?

Endovascular Aneurysm Repair

• Can be performed under GA or spinal anaesthesia.

Evidence

EVAR- 1 trial, which was conducted in 1000 patients fit for open repair. The 30- day mortality was one- third less at 1.7% (versus 4.7%), with statistical significance p = 0.009.

Therefore all elective AAA repairs should be EVAR unless there are technical limitations preventing its use:

• neck <2 cm
• aneurysm/aorta angle >60 degrees.

What is an endoleak and how are they classified?

An endoleak is defined as persistent blood flow outside the graft within the aneurysm sac.

Type 1: Urgent repair as essentially ruptured aneurysm.

Type 2: Conservative management as low-
pressure leak.

Type 3: Requires repair.

Type 4: Conservative management as leak contained (rare and therefore debatable).

What pre-op investigations would you perform for an elective AAA repair?

• FBC, UE, LFTs, coagulation screen, glucose, HbA1c if diabetic, lipids.
• Crossmatch 4 units.
• ECG.
• CXR.
• CT angiogram abdominal aorta.
• Exercise tolerance test/thallium.
• MUGA or ECHO (varies between units).
• ABG.

How would you repair a ruptured AAA?

The key manoeuvre in a ruptured AAA is converting an unstable case into an elective repair.

Key treatment steps

• Decision to operate in the first place.
• Consent with patient and relatives.
• Mobilise experienced theatre team.
• Initiate major transfusion protocol and ensure blood products available.
• Anaesthetic set-up: central line right internal jugular, arterial line, and urethral catheter. Anaesthetic agents to be administered only when surgeon ready.
• Prep and drape.
• Rapid opening of abdomen via long midline incision.
• Eviscerate small bowel and dissect duodenum to right.
• Proximal control of AAA neck:
  • ã infra-renal: divide left renal vein
  • ã supra-renal: split right crus of diaphragm/split lesser omentum for supra- coeliac control.
• Cross clamp on.
• Iliac control, then proceed as for elective repair.

What are the complications of AAA repair?

Complications may be classified as general and specific.

General

• Embolus.
• Thrombus.
• Cardiac.
• Respiratory/ARDS.
• Acute tubular necrosis.
• Ischaemic gut (IMA).

Specific

• Graft sepsis.
• Renal infarction.
• Gut ischaemia (IMA).
• Wound infection.
• Stroke.
• Incisional hernia.

How would you manage a post- op AAA who developed metabolic acidosis?

Causes

1. Acute tubular necrosis.
2. Ischemic left colon.
3. Abdominal compartment syndrome.

How would you do a brachial embolectomy?

• Heparin 5000 units IV.
• GA/local with anaesthetist present.
• Transverse incision at antecubital fossa.
• Split bicipital aponeurosis. NB: Median nerve is medial to artery.
• Proximal and distal control of brachial artery.
• Transverse arteriotomy (11 blade and Potts scissors).
• Embolectomy with size 3 and 4 Fogarty catheter.
• Heparin flush.
• 6/0 Prolene closure.
• Start warfarin post-op.

How would you manage a popliteal artery aneurysm?

Surgical therapy

Popliteal artery occlusion

Surgical therapy for popliteal artery occlusion is bypass of the occlusion, which can be achieved with grafts, including great saphenous vein (GSV) or prosthetic (e.g. polytetrafluoroethylene [PTFE]) grafts. GSV bypass can be used in a reversed, nonreversed or in situ orientation. The reverse vein bypass graft, first described by Kunlin in 1949, has become the favoured operation for bypass of an occluded popliteal artery. The ipsilateral GSV is the conduit of first choice. If that is unavailable, alternative autogenous conduit options that can be used include the contralateral GSV, arm veins (basilic and cephalic), the small saphenous vein, the superficial femoral vein, the popliteal vein, or cryopreserved veins.

The popliteal artery is accessible from medial thigh and calf incisions. The anastomosis can be performed either end-to-end or side-to-side. If the latter is chosen in the case of an aneurysm, the aneurysm must be excluded from the circulation by ligature.

Percutaneous transluminal angioplasty (PTA) is a less invasive intervention in the treatment of popliteal artery occlusive disease. PTA is indicated for short (<2 cm) lesions in patients who have claudication and good runoff. Initial enthusiasm that stents could increase long-term results of PTA has not been supported by subsequent studies. The primary patency rate at 1 year is 65%. However, PTA may be a reasonable alternative to open surgery for limb salvage indications in patients with prohibitive surgical risks.

Popliteal artery aneurysm

Elective surgical repair is indicated in all patients with PAA regardless of size. E...

Table of contents

• Cover Page
• Halftitle Page
• Title Page
• Copyright Page
• Contents
• About the author
• Preface
• Acknowledgements
• Part One
• Part Two
• References
• Index