Allograft replacement for infrarenal aortic graft infection

14° CONGRESS OF ASIAN SOCIETY FOR VASCULAR SURGERY

DANIELE MASOTTIDIVISION OF VASCULAR SURGERY

TREVISO HOSPITAL ITALY

Alexis Carrel reported the use of allograft in animal experiments

Robert Gross was the first to treat aortic coartationon by human arterial allograft

Charles Dubost replaced the infrarenal aorta with a fresh aortic allograft

A BRIEF HISTORY

ABDOMINAL AORTIC GRAFT INFECTION

Abdominal aortic graft infection is rare Operative mortality in patients with infected

aortic aneurysms remains high Abdominal aortic graft infection remains a

major surgical challenge

CLASSIFICATION

By time of apparence Early: < 4 months Late: > 4 months

By extent to post-operative wound infection Grade I: cellulitis involving the wound Grade II: infection involving sottocutaneus tissue Grade III: infection involving the vascular prosthesis

Bandyk

Szilagyi

CLINICAL MANIFESTATIONS

Leukocytosis and an elevated erythrocyte sedimentation rate (in 70% of the cases)

Weight loss The onset is insidiousus, and a low grade of

fever may be present for several months bifore diagnosis

Fever is present in over 70% of the patients

CLINICAL MANIFESTATIONS

Salmonella and gram negative infections have a greater tendency a early rupture and death

Overall mortality from abdominal aortic graft infection is over 50% despite advances in therapy

Diagnosis of the abdominal aortic graft infetion

BacteriologyGram stain

Blood cultureTissue culture

Clinical featuresSeptic symptomOperative findingSatellite infectionRisk factors

Imaging StudyCE-CT

MRIPET CT

WBC scan

DIAGNOSIS

Blood culture are helpful in suggesting the diagnosis and identifyng the pathogen (though 25% negative)

Abdominal ultrasnonography CT scan is generally performed preopertively

to assist in surgical planning

CT scan demonstrating abscess formation around an infected prosthetic graft

MANAGEMENT

Abdominal aortic gaft infection is treated with intravenous antibiotics and surgical exicision

Antibiotic therapy must be continued post-operatively for at least 6 weeks

MANAGEMENT

The standard surgical approach involves:

Resection of infected aortic aneurysm and infected retroperitoneal tissueOwersewing of the native aorta as stumpsRestoration of distal perfusion

ALLOGRAFT

The aim of this prospective , observational study was the evaluate the safety and efficacy of cryopreserved arterial allograft reconstruction in the treatment of abdominal aortic infection

ALLOGRAFT

Cryopreserved in liquid nitrogen

Expensive

Delay

ALLOGRAFT

Technical points

Unfreeze and rinse just before implantation

Ligature of side branches

Coverage of the graft

6 weeks of antibiotics

STUDY DESIGN IN PATIENTS WITH ABDOMINAL AORTIC GRAFT INFECTION

STUDY DESIGN 19 patients with abdominal aortic graft

infection presenting to our institution over a recent 8-years period were studied

INITIAL SURGERY

All patients were referred from other hospitals.

8 aortobifemoral bypasses 4 aorto-aortic grafts4 aortobiliac bypasses2 aortofemoral bypasses1 endoprosthesis

RESULTS

19 patient with infected aortic graft were treated with surgery with cryopreserved allograft

(November 1999-February 2007)

90% were febrile, 90% had leukocytosis and 30% were emodinamically unstable

The most common responsible pathogens were Staphylococcus aureus (31%)

BACTERIOLOGICAL DATAOrganisms:•No patogen cultured 3•Staphylococcus aureus 6•Staphylococcus epidermidis 1•Staphylococcus capitis 1•Proteus vulgaris 1•Proteus mirabilis 1•Candida glabrata 1•Escherichia coli 1•Staphylococcus hominis 1•Staphylococcus coag.neg. 1

•Multiple pathogens 2

INDICATION FOR CRYOPRESERVED AORTIC

ALLOGRAFT

→ 15 were patients for primary graft infection

(78,9%)

→ 1 patient for mycotic aneurism (5,3%)

→ 2 patients for aortoenteric fistulas (10,5%)

→ 1 patient for endoprostesis infection (5,3%)

RESULTS

Early postoperative mortality was 36,8% (7 patients) including 3 (15,79%) allograft related deaths from rupture of the allograft

Four deaths were not allograft related There were six (31,58%) non lethal allograft

complication (rupture n = 2, thromboses, which were successfully treated at repeat operation, n = 4

Amputation n = 1 One patient need dialitic treatment Four patients (21,05%) were lost to follow-up Mean follow-up was 24 months Late mortality was 10,53% (2 patients)

Postoperative aortogram shows bilateral revascularization in a patient who underwent allograft replacement to treat infrarenal ortic graft infection

AORTOENTERIC FISTULA

Direct communication between the aorta and the GI tract.

Aortoenteric Fistula (AEF) is a rare, lifethreatening disease process.

Most commonly a complication of repair of abdominal aortic aneurysms.

Occurs in approximately 0.3-2% of patients with open AAA repairs.

PROGNOSIS

Prognosis is poor Mortality rate of 100% if no surgical

intervention done. Mortality rate between 60-90% with surgical

intervention

CONCLUSION

Our experience with cryopreserved arterial allograft in the management of abdominal aortic infection suggests that this tecnique seems to be a useful option for treating one of the most dreaded vascular complications