Overview
Definition:
Endovascular Aneurysm Repair (EVAR) requires access to the femoral or iliac arteries to introduce endovascular devices
The method of arterial access and closure is a critical decision influencing procedural success, complications, and patient recovery.
Epidemiology:
EVAR is the predominant treatment for infrarenal abdominal aortic aneurysms (AAA) and some thoracic aortic aneurysms (TAAA)
Access site complications can occur in 5-15% of EVAR procedures, impacting morbidity and healthcare costs.
Clinical Significance:
Optimal access and closure technique can reduce operative time, length of hospital stay, blood loss, and the risk of access-related complications such as pseudoaneurysm, hematoma, infection, and limb ischemia, directly impacting patient outcomes and DNB/NEET SS exam knowledge.
Diagnostic Approach
History Taking:
Assess patient comorbidities: coagulopathy, peripheral arterial disease, previous groin surgeries or interventions
Document allergies to contrast agents or local anesthetics
Inquire about prior interventions in the access area
Red flags include active infection or severe obesity at the access site.
Physical Examination:
Palpate bilateral femoral pulses to assess adequacy for access
Examine the skin for integrity, presence of infection, or significant scarring
Assess limb perfusion
Evaluate the inguinal region for hernias or lymphadenopathy.
Investigations:
Pre-operative imaging (CTA of abdomen and pelvis) is crucial to evaluate the anatomy of the infrarenal aorta and iliac/femoral arteries, identifying tortuosity, calcification, and vessel diameter, which guides the choice of access strategy and closure device
Arterial duplex ultrasound can assess vessel patency if history or examination is equivocal.
Differential Diagnosis:
Not directly applicable for access technique selection itself, but understanding the underlying pathology (e.g., AAA, TAAA) is paramount for appropriate EVAR planning.
Management
Initial Management:
The decision between surgical cutdown and percutaneous access is made pre-operatively based on anatomical factors, patient comorbidities, and surgeon preference
Meticulous sterile technique is mandatory for all access methods.
Surgical Management:
Surgical cutdown involves a direct incision over the femoral artery, typically in the common femoral artery bifurcation
The artery is dissected, ligated proximally and distally, and an arteriotomy is made for device insertion
Closure is achieved with direct suture repair
This method is preferred in cases of inadequate percutaneous access, severe tortuosity, or heavy calcification
It offers excellent hemostasis and is reliable for large sheath insertion.
Percutaneous Management:
Percutaneous access utilizes pre-closure devices (e.g., Angio-Seal, Perclose) or post-closure techniques
Pre-closure involves deploying a device to approximate the arteriotomy site before sheath removal
Post-closure involves manual compression or a secondary closure device after sheath removal
This technique offers minimally invasive benefits, reduced operating time, and faster ambulation, but is dependent on adequate vessel wall for device efficacy and can be challenging in tortuous or heavily calcified vessels
Device failure may necessitate conversion to cutdown.
Supportive Care:
Post-procedure monitoring includes vigilance for bleeding, hematoma formation, pseudoaneurysm, limb ischemia, and infection at the access site
Mobilization protocols vary based on access technique and closure method
percutaneous access generally allows earlier mobilization.
Complications
Early Complications:
Hematoma formation at the access site
Hemorrhage
Pseudoaneurysm
Arterial dissection
Arteriovenous fistula
Local infection
Nerve injury
Limb ischemia due to thrombus or dissection.
Late Complications:
Chronic pseudoaneurysm
Persistent groin pain
Incisional hernia (more common with cutdown)
Stenosis at the access site
Chronic limb ischemia.
Prevention Strategies:
Careful patient selection and pre-operative assessment
Adequate imaging
Appropriate sheath size relative to vessel diameter
Meticulous technique during access and closure
Prompt recognition and management of any signs of bleeding or ischemia
Judicious use of anticoagulation and antiplatelet agents post-procedure
Patient education on activity restrictions.
Prognosis
Factors Affecting Prognosis:
The choice of access and closure technique can influence recovery time and the likelihood of access site complications
Patients with significant comorbidities may have poorer outcomes related to any access strategy
Early identification and management of complications are crucial.
Outcomes:
Successful EVAR with minimal access site complications is associated with rapid recovery, shorter hospital stays, and reduced morbidity
Major access site complications can lead to re-intervention, prolonged hospitalization, and increased costs.
Follow Up:
Routine follow-up with physical examination and duplex ultrasound of the access site is recommended, particularly in patients who experienced early complications or who have risk factors for pseudoaneurysm formation
Adherence to post-operative mobilization and activity guidelines is important.
Key Points
Exam Focus:
Understand indications for each access method: Surgical cutdown for difficult anatomy (tortuosity, calcification, small vessel) or large sheath needs
Percutaneous for simpler anatomy, desire for minimally invasive approach
Recognize complications and their management
Know closure device types and their limitations.
Clinical Pearls:
Always perform a bilateral femoral pulse assessment
Consider pre-closure devices for patients on anticoagulation
If percutaneous closure fails, do not hesitate to convert to a surgical cutdown
it is safer and more definitive
Small hematomas may resolve spontaneously, but expanding hematomas or signs of ischemia require immediate attention.
Common Mistakes:
Attempting percutaneous access in severely tortuous or calcified iliac/femoral arteries without appropriate pre-planning
Over-reliance on closure devices without adequate vessel wall integrity
Delaying conversion to surgical cutdown when percutaneous access is failing
Inadequate post-operative surveillance of the access site.