SCOTTSDALE, ARIZ. – Acute renal failure occurred postoperatively in one-third of patients who underwent endograft explantation after endovascular abdominal aortic aneurysm repair (EVAR), according to the results of a small retrospective study.
The perioperative infected EVAR (I-EVAR) mortality across the study’s 36 patient records (83% male patients, average age 69 years), culled from four surgery centers’ data from 1997 to 2014, was 8%. The overall mortality was 25%, according to Dr. Victor J. Davila of Mayo Clinic Arizona, Phoenix, and his colleagues. Dr. Davila presented the findings at the Southern Association for Vascular Surgery annual meeting.
“These data show that I-EVAR explantation can be performed safely, with acceptable morbidity and mortality,” said Dr. Davila, who noted that while acceptable, the rates were still high, particularly for acute renal failure.
Whitney McKnight/Frontline Medical News
Dr. Victor J. Davila
“We did not find any difference between the patients who developed renal failure and the type of graft, whether or not there was suprarenal fixation, and an incidence of postoperative acute renal failure,” Dr. Davila said, “However, because acute renal failure is multifactorial, we need to minimize aortic clamp time, as well as minimize the aortic intimal disruption around the renal arteries.”
Three deaths occurred within 30 days post operation, all from anastomotic dehiscence. Additional short-term morbidities included respiratory failure that required tracheostomy in three patients, and bleeding and sepsis in two patients each. Six patients required re-exploration because of infected hematoma, lymphatic leak, small-bowel perforation, open abdomen at initial operation, and anastomotic bleeding. Six more deaths occurred at a mean follow-up of 402 days. One death was attributable to a ruptured aneurysm, another to a progressive inflammatory illness, and four deaths were of indeterminate cause.
Only three of the explantations reviewed by Dr. Davila and his colleagues were considered emergent. The rest (92%) were either elective or urgent. Infected patients tended to present with leukocytosis (63%), pain (58%), and fever (56%), usually about 65 days prior to explantation. The average time between EVAR and presentation with infection was 589 days.
Although most underwent total graft excision, two patients underwent partial excision, including one with a distal iliac limb infection that showed no sign of infection within the main portion of the endograft. Nearly three-quarters of patients had in situ reconstruction.
While nearly a third of patients had positive preoperative blood cultures indicating infection, 81% of intraoperative cultures taken from the explanted graft, aneurysm wall, or sac contents indicated infection.
The gram-positive Staphylococcus and Streptococcus were the most common organisms found in cultures (33% and 17%, respectively), although anaerobics were found in a third of patients, gram negatives in a quarter of patients, and fungal infections in 14%. A majority (58%) of patients received long-term suppressive antibiotic therapy.
Surgeons should reserve the option to keep a graft in situ only in infected EVAR patients who likely would not survive surgical explantation and reconstruction, Dr. Davila said. “Although I believe [medical management] is an alternative, the best course of action is to remove the endograft.”
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