Evar

Surgical approach

Usually performed in a hybrid theatre/angiography suite with fluoroscopy and contrast
- Endovascular stent-graft deployed to exclude aneurysm sac (commonly infrarenal AAA; also thoracic TEVAR variants)
- Contrast angiography before/after deployment to confirm position and endoleak
Access typically via bilateral common femoral arteries
- Percutaneous closure devices or surgical cut-down; large-bore sheaths
Key procedural steps
- Systemic heparinisation after access (target ACT often >250 s; local protocol)
- Device introduction, positioning under fluoroscopy, deployment of main body + iliac limbs
- Balloon moulding; completion angiogram; closure and haemostasis
Potential intraoperative events driven by surgical/IR actions
- Rapid pacing (more common in TEVAR) to reduce aortic movement during deployment
- Conversion to open repair for rupture, access failure, maldeployment, uncontrolled bleeding

Anaesthetic management (overview)

Type of anaesthesia: GA or regional/LA with sedation (institution- and patient-dependent)
- GA often preferred for complex anatomy, longer cases, inability to lie flat, severe anxiety, anticipated conversion, respiratory compromise, or need for breath-holds/immobility
- LA ± sedation / neuraxial may reduce physiological stress, facilitate early mobilisation, and shorten stay in selected patients
Airway: ETT for GA; SGA possible for short, stable cases but consider access to airway in remote/hybrid environment
- If LA/sedation: plan for rescue airway with limited access (arms tucked, drapes, imaging equipment)
Duration: typically 1.5–3 hours (longer if complex fenestrated/branched EVAR or difficult access)
How painful: usually mild–moderate (groin access pain); less than open AAA repair
- Analgesia often paracetamol ± opioid; consider local infiltration at groins; avoid over-sedation
Haemodynamic goals: maintain organ perfusion; anticipate swings with bleeding, pacing, contrast, and limb/ischaemia events
- Avoid hypotension (renal/spinal/mesenteric ischaemia risk) and severe hypertension (endoleak/bleeding risk)

Indications and patient selection

Elective infrarenal AAA meeting size/growth criteria (local vascular guidance; commonly ≥5.5 cm in men, ≥5.0 cm in women, rapid growth, symptomatic aneurysm)
High surgical risk patients where open repair risk is high (cardiorespiratory comorbidity)
Emergency: ruptured AAA in selected centres (rEVAR) depending on anatomy and logistics
Anatomical suitability: adequate proximal neck length/angulation, iliac access, landing zones; complex fenestrated/branched devices for challenging anatomy

Preoperative assessment (FRCA focus)

Cardiovascular risk: AAA patients often have diffuse atherosclerosis
- Assess IHD, heart failure, valvular disease, arrhythmia; functional capacity; consider echo if indicated
- Medication review: beta-blockers, statins, antihypertensives; antiplatelets/anticoagulants (balance bleeding vs thrombosis; follow local protocol)
Respiratory: COPD common; optimise bronchodilators; smoking cessation; consider ABG if severe disease
Renal: baseline creatinine/eGFR; contrast-induced nephropathy risk; diabetes; dehydration; ACEi/ARB considerations
- Plan hydration strategy; minimise nephrotoxins; discuss contrast load with team
Haematology: FBC, coagulation; group & screen/crossmatch (major haemorrhage possible though less common than open)
- Have MHP available; cell salvage may be used if conversion/open anticipated
Neurology/spinal cord risk: mainly relevant to thoracic/extent repairs; consider baseline neuro status and spinal protection strategy if TEVAR/complex
Environment planning: remote site, radiation, limited access to patient, equipment compatibility
- Check monitoring leads/infusions positioned to allow C-arm movement; long extensions; secure airway access plan

Anaesthetic techniques: pros/cons and practicalities

Local anaesthesia ± sedation
- Advantages: less myocardial depression, faster recovery, fewer pulmonary complications, early mobilisation
- Disadvantages: patient movement, discomfort during sheath manipulation, need for cooperation, risk of oversedation/airway compromise in remote environment
- Sedation: titrate (e.g., remifentanil/propofol infusions) with capnography; maintain verbal contact if possible
Neuraxial (spinal/epidural) ± sedation
- Consider anticoagulation/heparinisation timing and ASRA/RA-UK guidance; risk of hypotension in vasculopaths
- Epidural less commonly needed than open repair; may be useful if conversion risk and plan agreed
General anaesthesia
- Advantages: immobility, controlled ventilation (CO2 for imaging), easier management of complications/conversion
- Disadvantages: haemodynamic depression, ventilation/perfusion issues in COPD, longer recovery
- Airway: ETT usually; consider lung-protective ventilation; avoid high intrathoracic pressures that reduce venous return

Monitoring and access

Standard monitoring + temperature + urine output (especially if prolonged/contrast load)
Arterial line: commonly used (beat-to-beat BP, blood sampling); site away from radiation field and accessible
IV access: at least 2 large-bore cannulae; consider rapid infuser availability; long extension lines
Central venous access: not routine; consider for poor access, vasoactive infusions, complex/ruptured cases
Blood: group & save vs crossmatch depending on complexity; ensure MHP pathway known

Intraoperative management: key physiological issues

Anticoagulation: systemic heparin after access; monitor ACT if used; reversal with protamine per protocol
- Be alert to protamine reactions (hypotension, pulmonary hypertension, anaphylactoid reactions)
Haemodynamics: treat hypotension promptly (bleeding, vasodilation, myocardial ischaemia, arrhythmia, IVC compression, pacing)
- Vasopressors commonly needed (metaraminol/phenylephrine/noradrenaline); tailor to HR/contractility
Myocardial ischaemia: high-risk cohort; maintain oxygenation, Hb, coronary perfusion pressure; avoid tachycardia
Renal protection: avoid hypotension; maintain euvolaemia; minimise contrast where possible; consider bicarbonate/acetylcysteine only if per local policy (evidence mixed)
Contrast reactions: anaphylactoid reactions and bronchospasm possible; ensure emergency drugs available and team aware
Radiation safety: time, distance, shielding; dosimeter; protect thyroid/eyes; keep hands out of beam
Temperature: forced-air warming as feasible; cold contrast/fluids; hypothermia worsens coagulopathy

Complications (know classification and anaesthetic implications)

Access site complications: bleeding/haematoma, pseudoaneurysm, arterial dissection/rupture, limb ischaemia
- May present as hypotension, falling Hb, groin swelling, loss of distal pulses, pain
Endoleak (persistent flow into aneurysm sac)
- Type I: inadequate seal at proximal/distal attachment (high pressure; urgent correction)
- Type II: retrograde flow from branch vessels (e.g., lumbar/IMA); often surveillance unless sac expands
- Type III: graft defect/modular disconnection (high pressure; urgent correction)
- Type IV: graft porosity (rare with modern grafts)
- Type V: endotension (sac expansion without visible leak)
Aneurysm rupture (intra- or post-procedure): catastrophic haemorrhage; may require conversion to open repair
- Activate MHP; permissive hypotension may be used in uncontrolled bleeding until proximal control (case-dependent, consultant-led)
Embolisation: cholesterol/thrombus → limb ischaemia, renal/mesenteric ischaemia
Renal failure: contrast nephropathy, atheroembolism, renal artery compromise
Spinal cord ischaemia: more relevant to TEVAR/extensive coverage; presents as paraparesis/paraplegia
- Risk factors: extensive aortic coverage, hypotension, prior aortic surgery, occlusion of hypogastric/subclavian, anaemia
- Management principles: maintain MAP, optimise Hb/oxygenation, consider CSF drainage per protocol, avoid hypothermia
Post-implantation syndrome: fever, raised inflammatory markers, malaise (self-limiting; exclude infection)

Postoperative care

Destination: PACU/ward for uncomplicated elective EVAR; HDU/ICU if significant comorbidity, haemodynamic instability, renal risk, complex repair, or rEVAR
Analgesia: paracetamol ± opioid; local anaesthetic infiltration; avoid NSAIDs if renal risk/bleeding risk
Monitor: limb perfusion (pulses, colour, pain), groin haematoma, urine output/creatinine, ECG/troponin if indicated
Antithrombotics: restart antiplatelets/anticoagulants per vascular plan; VTE prophylaxis
Imaging follow-up: surveillance for endoleak and sac size (CT/duplex per protocol)

You are asked to anaesthetise a 78-year-old with COPD, CKD3 and IHD for elective EVAR. Talk through your preoperative assessment and optimisation.

Structure: comorbidities + investigations + optimisation + consent/communication + planning for complications/conversion.

Cardiac: symptoms/functional capacity, recent ACS/stents, angina control, HF signs; ECG; troponin only if symptomatic; echo if murmur/HF/poor METs with unclear function
Respiratory: COPD severity, exacerbations, sputum, exercise tolerance; optimise inhalers, treat infection, consider steroids if recent exacerbation; baseline SpO2/ABG if severe
Renal: baseline creatinine/eGFR, electrolytes; contrast nephropathy risk; ensure hydration plan; avoid nephrotoxins; discuss contrast volume with operator
Medications: continue beta-blocker/statin; clarify ACEi/ARB day-of-surgery policy; plan for antiplatelets/anticoagulants with surgeon/haematology
Blood: FBC/coag; group & save/crossmatch depending on complexity; ensure major haemorrhage protocol available
Shared plan: discuss anaesthetic technique (GA vs LA/sedation), possibility of conversion to open repair, postoperative destination (HDU if high risk)

Discuss the advantages and disadvantages of local anaesthesia with sedation versus general anaesthesia for EVAR.

Examiners want: patient factors, procedural factors, environment, and safety/rescue plan.

LA/sedation advantages: less myocardial depression, fewer pulmonary complications, quicker recovery, earlier mobilisation, potentially shorter length of stay
LA/sedation disadvantages: movement, discomfort, prolonged cases, oversedation/airway compromise, limited airway access in hybrid suite, conversion to GA may be challenging
GA advantages: immobility, controlled ventilation/CO2, easier management of complications, easier conversion to open repair, better tolerance of long/complex cases
GA disadvantages: haemodynamic instability, higher pulmonary complication risk in COPD, longer recovery; need for invasive monitoring more likely
Decision: individualise (anatomy complexity, expected duration, patient cooperation, comorbidities, team experience, location constraints)

Intraoperatively the blood pressure suddenly drops during EVAR. Give a differential diagnosis and immediate management.

Approach: ABC + check monitors + communicate + treat likely causes in parallel.

Immediate actions: call for help, inform surgeon, increase FiO2, check pulse/ECG, confirm arterial trace, assess ventilation/ETCO2, check access/infusions
Bleeding/rupture/access vessel injury: look for groin swelling, falling Hb, rising HR, decreasing ETCO2; request angiographic check; activate MHP if suspected
Anaesthetic causes: excessive depth, vasodilation (propofol), high neuraxial block, anaphylaxis (including contrast), protamine reaction
Cardiac causes: myocardial ischaemia, arrhythmia, RV failure/PE, tamponade (rare); treat per ALS/ACLS principles
Management: vasopressor boluses (metaraminol/phenylephrine), start noradrenaline if persistent; fluid/blood guided by context; obtain ABG, Hb, lactate; prepare for conversion

Explain contrast-induced nephropathy risk in EVAR and how you would reduce it perioperatively.

Key is haemodynamic stability and avoidance of additional renal insults.

Risk factors: pre-existing CKD, diabetes, dehydration, heart failure, large contrast volume, hypotension, nephrotoxic drugs
Pre-op: check baseline renal function; ensure euvolaemia; consider holding nephrotoxins (e.g., NSAIDs); coordinate contrast minimisation
Intra-op: avoid hypotension; maintain MAP and perfusion; balanced crystalloid to maintain euvolaemia; monitor urine output; avoid unnecessary diuretics
Post-op: monitor creatinine/UO; avoid nephrotoxins; treat sepsis/low output states early; involve renal team if AKI develops

Describe endoleaks after EVAR and their clinical significance.

Common FRCA viva topic: classification + pressure + urgency.

Type I (attachment site leak): proximal or distal inadequate seal → high-pressure leak; usually requires urgent endovascular correction
Type II (branch retrograde): lumbar/IMA back-bleeding → often low pressure; observe unless sac expands or persistent
Type III (graft defect/disconnection): high-pressure; urgent correction
Type IV (porosity): rare; often self-limiting
Type V (endotension): sac expansion without visible leak; may need intervention

How does EVAR differ from open AAA repair in terms of anaesthetic considerations and physiological stress?

Contrast key stressors: aortic cross-clamp vs contrast/radiation/access complications.

EVAR avoids laparotomy and aortic cross-clamping → less afterload change, less ischaemia–reperfusion, less fluid shift, less pain
EVAR still carries risk of major haemorrhage (rupture/access), myocardial events, AKI (contrast/embolism), limb ischaemia
Environment: remote/hybrid theatre, radiation, limited access to patient; need for robust set-up and rescue plan
Post-op: typically shorter stay and less analgesic requirement; ongoing surveillance for endoleak

You are doing EVAR under sedation. The patient becomes agitated and starts moving during stent deployment. What do you do?

Assesses crisis management, communication, and airway planning in remote environments.

Immediate: tell operator to pause deployment if possible; ensure patient safety (arms, lines, sterile field); increase oxygen; check capnography and airway patency
Assess cause: pain (groin/sheath), hypoxia/hypercapnia, hypotension, full bladder, anxiety/delirium
Treat: titrate analgesia (small opioid bolus or adjust remifentanil), deepen sedation carefully (propofol), consider local infiltration top-up
If unsafe/ongoing: convert to GA early with pre-agreed plan; call for additional anaesthetic help; ensure airway access and equipment positioning

What are the specific hazards of working in a hybrid theatre/angiography suite and how do you mitigate them?

Key points: radiation, remote site, access, equipment, communication.

Radiation: wear lead apron/thyroid shield, dosimeter; maximise distance, minimise time; use shielding; keep hands out of beam
Limited patient access: plan airway strategy; secure lines; use long extensions; position monitoring where visible; ensure suction and difficult airway kit immediately available
Equipment: check compatibility with imaging (e.g., avoid artefact), ensure infusion pumps and ventilator can be positioned safely
Team factors: pre-brief, clear conversion-to-open plan, define roles in haemorrhage/contrast reaction

Outline your plan for major haemorrhage during EVAR, including communication and transfusion strategy.

Focus: early recognition, MHP activation, balanced transfusion, haemostatic resuscitation, and preparation for conversion.

Recognise: sudden hypotension, tachycardia, falling ETCO2, increasing vasopressor requirement, visible bleeding/groin swelling; confirm with surgeon/angiography
Actions: call for help, activate MHP, large-bore access, rapid infuser, warm patient/fluids, send urgent labs (FBC, coag, fibrinogen, ABG, lactate, calcium)
Transfusion: balanced RBC:FFP:platelets per local MHP; early fibrinogen replacement if low; give calcium; consider TXA early if appropriate
Haemodynamic strategy: vasopressors as bridge; consider permissive hypotension only if uncontrolled bleeding and agreed with surgeon; aim for definitive control/conversion
Post-event: ICU, ongoing correction of coagulopathy/hypothermia/acidosis; document and debrief

A patient develops hypotension and bronchospasm shortly after contrast injection. How do you manage this?

Treat as anaphylaxis/anaphylactoid reaction until proven otherwise.

Stop trigger if possible; call for help; high-flow oxygen; assess airway and ventilation; prepare for intubation if deteriorating
Give adrenaline titrated to severity (IV boluses in anaesthetised patient); start infusion if refractory; give IV fluids
Adjuncts: chlorphenamine, hydrocortisone; bronchodilators (salbutamol); consider nebulised adrenaline if upper airway oedema
Investigations: tryptase samples; document contrast agent; refer to allergy clinic; plan future contrast avoidance/premedication per specialist advice

Describe the anaesthetic considerations for endovascular repair of an abdominal aortic aneurysm.

A common structured FRCA topic: technique choice, monitoring, haemodynamic goals, complications, and post-op care.

Technique: GA vs LA/sedation vs neuraxial; justify choice based on patient, complexity, and conversion risk
Monitoring/access: arterial line, large-bore IV, blood availability, temperature and urine output; consider CVC in complex/ruptured cases
Key intra-op issues: heparinisation/ACT, contrast load and renal protection, haemodynamic swings and myocardial ischaemia, radiation/remote site constraints
Complications: access bleeding, rupture, endoleak, embolisation/limb ischaemia, AKI; plan for MHP and conversion to open repair
Post-op: analgesia, limb checks, renal monitoring, cardiac monitoring in high-risk patients, surveillance imaging

Compare and contrast EVAR with open repair of AAA from the anaesthetist’s perspective.

Examiners expect a table-like comparison in words: physiology, monitoring, analgesia, complications, and postoperative course.

Open: laparotomy + cross-clamp → major afterload changes, ischaemia–reperfusion, large fluid shifts, significant pain; EVAR: less physiological insult but still high-risk cohort
Monitoring: both often need arterial line; open more likely to need CVC, cardiac output monitoring, epidural; EVAR may be done with LA/sedation
Renal: open risk from clamp/ischaemia; EVAR risk from contrast/embolism; hypotension harmful in both
Complications: open—bleeding, ileus, respiratory failure; EVAR—endoleak, access complications, radiation/contrast issues; both—MI/stroke risk
Post-op: open often ICU/HDU and higher opioid/epidural needs; EVAR often quicker recovery but requires long-term surveillance

What are the causes of acute kidney injury after EVAR and how would you manage it?

Expect multifactorial causes and a practical management plan.

Causes: contrast nephropathy, hypotension/low cardiac output, atheroembolism, renal artery compromise, sepsis, nephrotoxins
Immediate management: assess volume status and haemodynamics; optimise MAP; stop nephrotoxins; monitor UO and labs; ultrasound if obstruction/renal artery issue suspected
Supportive care: fluid balance, electrolyte management (K+), acid-base; consider renal referral early; RRT if refractory hyperkalaemia, acidosis, pulmonary oedema, uraemic complications

Describe the classification of endoleaks and which are most concerning.

High-pressure leaks (I and III) are typically most urgent.

Type I and III: high-pressure → higher rupture risk → usually require urgent correction
Type II: often observe unless sac expansion/persistence
Type IV/V: uncommon; manage according to sac behaviour and specialist advice