Primary Graft Infection Research Articles

Endovascular Treatment of Infected Aortic Aneurysms: A Retrospective Multicenter Analysis from the GORE®GREAT Registry Study

Objective: The Global Registry for Endovascular Aortic Treatment (GREAT), which is a retrospective sponsored registry (W.L Gore & Associates; Flagstaff – AZ; USA), was queried to evaluate the outcomes of infected aortic aneurysms (inf-AAs) after abdominal (EVAR) or thoracic endovascular aortic repair (TEVAR). Methods: This is a multicenter, observational cohort study. For the current study, all patients were treated only with the standard GORE® devices for INFAA. Primary graft infections, aorto-enteric fistulae, and graft-enteric fistulae were excluded, as well as cases that did not meet the predefined criteria of an inf-AA. All serious adverse events within 30 days of the procedure were documented by sites. Primary outcomes were early (≤ 30 days) and late survival, and freedom from endograft infection. Results: Thirty-one (0.6% of the entire GREAT cohort) patients met the inclusion criteria and were included: 23 (74.2%) were males and 8 (25.8%) females. The mean age was 72 years ± 11 (range, 49-92). This included 26 (83.9%) abdominal inf-AAs and 5 (16.1%) thoracic inf-AAs. Operative-related mortality occurred in 1 (3.2%) patient. Immediate conversion to open surgical repair was not required. Mean follow-up was 23.6 ± 15 months (range, 1-49): estimated survival rate was 80% (95%CI, 60.8-90.5) at 12 months, and 53.2% (95%CI, 30.0-71.1) at 48 months. Secondary aortic rupture as well as endograft explanation was also not reported. Conclusion: Endovascular treatment of inf-AA is feasible and effective. While endograft infection was not detected during the follow-up, long-term results from GREAT registry may reveal how durable T/EVAR could be for inf-AAs.

Primary aortoenteric fistula following endovascular aortic repair due to type II endoleak

An 84-year-old female was lost to follow-up after endovascular aneurysm repair at another hospital with known type II endoleak. She later presented with presyncope and hematemesis. A referral center esophagogastroduodenoscopy showed possible duodenal diverticulum. She had recurrent symptoms and repeat computed tomography scan showed air within the aortic sac. At our center, she underwent stent graft explantation and axillofemoral reconstruction for a primary aortoenteric fistula. She was discharged and is doing well 5 months postoperatively. A high degree of suspicion for aortoenteric fistula is imperative in any patient with upper gastrointestinal hemorrhage after open or endovascular abdominal aortic aneurysm repair.

In-situ Revascularisation for Patients with Aortic Graft Infection: A Single Centre Experience with Silver Coated Polyester Grafts

Objective: The aim of this study was to evaluate the early and mid term outcom of patients with aortic graft infection who underwent in-situ revascularisation with a silver coated prosthesis. Material: From January 2000 to December 2006, 24 consecutive patients (22 male, 2 female) with mean age 67 years were prospectively entered in this study of aortic graft infection at our single centre. Infection was managed with either total (n = 19) or partial (n = 5) excision of the infected graft and in- situ reconstruction with a silver coated prosthesis, Inter Gard Silver (IGSG). Methods: The primary endpoint was recurrence of infection. Secondary endpoints were early and late mortality, peri-operative morbidity, primary graft patency, major amputation rates and patient survival. Results: Fourteen patients had a primary graft infection, however 10 of 24 patients had graft infection secondary to aorto digestive (n = 9) or aorto urinary (n = 1) tract fistulas. Bacteriological cultures were negative in 8 (33%) patients. Most organisms cultivated where virulent and the majority of graft infections were polymicrobial (71%). Silver grafts were placed emergently in 6 (25%) patients. Mean follow up 32.5 ± 31.0 months (range 2–78 months). Peri-operative morbidity and mortality were 46% and 21% respectively. Early interventions occurred in 6 (25%) patients and late secondary intervention were required in 3 (15.7%), caused by silver graft reinfection. The late mortality was 26%. Conclusion: In-situ reconstruction with the silver graft confirms similarity with other modalities. The greatest advantage for the silver graft is its ease of use but the risk of reinfection remains significant.

In-situ Revascularisation for Patients with Aortic Graft Infection: A Single Centre Experience with Silver Coated Polyester Grafts

Objective The aim of this study was to evaluate the early and mid term outcome of patients with aortic graft infection who underwent in-situ revascularisation with a silver coated prosthesis. Material From January 2000 to December 2006, 24 consecutive patients (22 male, 2 female) with mean age 67 years were prospectively entered in this study of aortic graft infection at our single centre. Infection was managed with either total ( n = 19) or partial ( n = 5) excision of the infected graft and in- situ reconstruction with a silver coated prosthesis, Inter Gard Silver (IGSG). Methods The primary endpoint was recurrence of infection. Secondary endpoints were early and late mortality, peri-operative morbidity, primary graft patency, major amputation rates and patient survival. Results Fourteen patients had a primary graft infection, however 10 of 24 patients had graft infection secondary to aorto digestive ( n = 9) or aorto urinary ( n = 1) tract fistulas. Bacteriological cultures were negative in 8 (33%) patients. Most organisms cultivated where virulent and the majority of graft infections were polymicrobial (71%). Silver grafts were placed emergently in 6 (25%) patients. Mean follow up 32.5 ± 31.0 months (range 2–78 months). Peri-operative morbidity and mortality were 46% and 21% respectively. Early interventions occurred in 6 (25%) patients and late secondary intervention were required in 3 (15.7%), caused by silver graft reinfection. The late mortality was 26%. Conclusion In-situ reconstruction with the silver graft confirms similarity with other modalities. The greatest advantage for the silver graft is its ease of use but the risk of reinfection remains significant.

Allograft replacement for infrarenal aortic graft infection: early and late results in 179 patients

Objectives We evaluated early and late results of allograft replacement to treat infrarenal aortic graft infection in a large number of patients and compared the results in patients who received fresh allografts versus patients who received cryopreserved allografts. Methods From 1988 to 2002 we operated on 179 consecutive patients (mean age, 64.6 ± 9.0 years; 88.8% men). One hundred twenty-five patients (69.8%) had primary graft infections, and 54 patients (30.2%) had secondary aortoenteric fistulas (AEFs). Fresh allografts were used in 111 patients (62.0%) until 1996, and cryopreserved allografts were used in 68 patients (38.0%) thereafter. Results Early postoperative mortality was 20.1% (36 patients), including four (2.2%) allograft-related deaths from rupture of the allograft (recurrent AEF, n = 3), all in patients with fresh allografts. Thirty-two deaths were not allograft related. Significant risk factors for early mortality were septic shock ( P < .001), presence of AEF ( P = .04), emergency operation ( P = .003), emergency allograft replacement ( P = .0075), surgical complication ( P = .003) or medical complication ( P < .0001), and need for repeat operation ( P = .04). There were five (2.8%) nonlethal allograft complications (rupture, n = 2; thromboses, which were successfully treated at repeat operation, n = 2; and amputation, n = 1), all in patients with fresh allografts. Four patients (2.2%) were lost to follow-up. Mean follow-up was 46.0 ± 42.1 months (range, 1-148 months). Late mortality was 25.9% (37 patients). There were three (2.1%) allograft-related late deaths from rupture of the allograft, at 9, 10, and 27 months, respectively, all in patients with fresh allografts. Actuarial survival was 73.2% ± 6.8% at 1 year, 55.0% ± 8.8% at 5 years, and 49.4% ± 9.6% at 7 years. Late nonlethal aortic events occurred in 10 patients (7.2%; occlusion, n = 4; dilatation < 4 cm, n = 5; aneurysm, n = 1), at a mean of 28.3 ± 28.2 months, all but two in patients with fresh allografts. The only significant risk factor for late aortic events was use of an allograft obtained from the descending thoracic aorta ( P = .03). Actuarial freedom from late aortic events was 96.6% ± 3.4% at 1 year, 89.3% ± 6.6% at 3 years, and 89.3% ± 6.6% at 5 years. There were 63 late, mostly occlusive, iliofemoral events, which occurred at a mean of 34.9 ± 33.7 months in 38 patients (26.6%), 28 of whom (73.7%) had received fresh allografts. The only significant risk factor for late iliofemoral events was use of fresh allografts versus cryopreserved allografts ( P = .03). Actuarial freedom from late iliofemoral events was 84.6% ± 7.0% at 1 year, 72.5% ± 9.0% at 3 years, and 66.4% ± 10.2% at 5 years. Conclusions Early and long-term results of allograft replacement are at least similar to those of other methods to manage infrarenal aortic graft infections. Rare specific complications include early or late allograft rupture and late aortic dilatation. The more frequent late iliofemoral complications may be easily managed through the groin. These complications are significantly reduced by using cryopreserved allografts rather than fresh allografts and by not using allografts obtained from the descending thoracic aorta.

The Chemically Treated Bovine Ureter—Clinical Performance of a Novel Biological Vascular Prosthesis

Aim This paper describes the rationale, development and clinical performance of a novel small-diameter vascular prosthesis of non-vascular animal tissue origin. Method Durable conduits suitable for coronary and peripheral arterial reconstruction are prepared for the first time from non-vascular animal tissue. Australian bovine ureters from young steers from protected herds are processed to form strong, bloodflow-compatible and non-immunogenic biologic grafts (‘Flonova’ R, Bionova International Pty Ltd, Melbourne). Fifty-six patients lacking suitable autogenous veins received 62 prostheses (32 bypasses were implanted above knee and 30 below knee). Determination of patency and function included Doppler ultrasound, duplex scanning and angiography. Findings The primary patency rate at 1, 2 and 5 years, respectively was 67, 59 and 52% and the secondary patency for the same time frames was 88, 73 and 61%. There were no occlusions as a result of intimal hyperplasia. Dilatation of the wall was diagnosed in one prosthesis at 3.5 years, and one at 7 years, and a false aneurysm of unknown aetiology occurred in another at 3 months. There were no primary graft infections. Conclusion This evaluation shows the chemically treated bovine ureter (CTBU) is a viable medium-term alternative to the currently available artificial vascular prostheses for peripheral revascularisation.

The chemically treated bovine ureter—clinical performance of a novel biological vascular prosthesis

Aim: This paper describes the rationale, development and clinical performance of a novel small-diameter vascular prosthesis of non-vascular animal tissue origin. Method: Durable conduits suitable for coronary and peripheral arterial reconstruction are prepared for the first time from non-vascular animal tissue. Australian bovine ureters from young steers from protected herds are processed to form strong, bloodflow-compatible and non-immunogenic biologic grafts (‘Flonova’ R, Bionova International Pty Ltd, Melbourne). Fifty-six patients lacking suitable autogenous veins received 62 prostheses (32 bypasses were implanted above knee and 30 below knee). Determination of patency and function included Doppler ultrasound, duplex scanning and angiography. Findings: The primary patency rate at 1, 2 and 5 years, respectively was 67, 59 and 52% and the secondary patency for the same time frames was 88, 73 and 61%. There were no occlusions as a result of intimal hyperplasia. Dilatation of the wall was diagnosed in one prosthesis at 3.5 years, and one at 7 years, and a false aneurysm of unknown aetiology occurred in another at 3 months. There were no primary graft infections. Conclusion: This evaluation shows the chemically treated bovine ureter (CTBU) is a viable medium-term alternative to the currently available artificial vascular prostheses for peripheral revascularisation.

Abdominal aortic reconstruction in infected fields: Early results of the United States cryopreserved aortic allograft registry

Objective: Aortic reconstructions for primary graft infection (PGI), mycotic aneurysm (MA), and aortic graft-enteric erosion (AEE) bear high morbidity and mortality rates, and current treatment options are not ideal. Cryopreserved grafts have been implanted successfully in infected fields and may be suitable for abdominal aortic reconstructions. Registry data from several institutions were compiled to examine results of cryopreserved aortic allograft (CAA) placement. Methods: The experience of 31 institutions was reviewed for CAAs inserted from March 4, 1999, to August 23, 2001. Indications for CAA, organisms, mortality, and complications were identified. Results: Fifty-six patients, 43 men and 13 women, with a mean age of 66 years (range, 44 to 90 years) had in situ aortic replacement with CAA. Indications for CAA placement were PGI in 43 patients (77%), MA in seven (14%), AEE in four (7%), and aortic reconstruction with concomitant bowel resection in two (4%). Infectious organisms were identified in 33 patients (59%); the most frequent organism was Staphylococcus aureus in 17 (52%). Thirty-one patients (55%) needed an additional cryopreserved segment for reconstruction. The mean follow-up period was 5.3 months (range, 1 to 22 months). One patient died in the operating room, and the 30-day surgical mortality rate was 13% (7/56). Seven additional patients died during the follow-up period, yielding an overall mortality rate of 25% (14 patients). Two patients (4%) had graft-related mortality as the result of hemorrhage from the CAA and persistent infection. Graft-related complications included persistent infection with perianastomotic hemorrhage in five patients (9%), graft limb occlusion in five (9%), and pseudoaneurysm in one (2%). Three patients (5%) needed amputation. Conclusion: In situ aortic reconstruction with CAA in infected fields carries a high mortality rate, but most deaths are not the result of allograft failure. However, CAA infection and lethal hemorrhage caused by graft rupture occurs and is concerning. Early reinfection was not reported. Late graft-related complications, such as reinfection, thrombosis, or aneurysmal changes, are unknown. Preliminary data from this registry fail to justify the preferential use of CAA for PGI, MA, or AEE. A multicenter, randomized study is needed to compare results with established techniques. (J Vasc Surg 2002;35:847-52.)

Long-term follow-up after in situ graft replacement in patients with aortofemoral graft infections

Aortic graft infection is among the most dreaded complications in vascular surgery. Regardless of management, it leads to high morbidity and mortality. Successful treatment traditionally involves removal of the infected prosthesis and revascularisation of the lower extremities by an extra-anatomic bypass. >3 Initial reviews of institutional series of patients with aortic graft infection emphasised the immediate postoperative mortality and morbidity. The long-term success of conventional treatment is measured in terms of patient survival, limb salvage and the abscence of complications related to graft excision, for example aortic stump blow-out. 4-1° As a treatment option for selected patients no clinical evidence of septicaemia or retroperitoneal purulent collections and no bacteriological evidence of pseudomonas infectionmany vascular surgeons now prefer in situ graft replacement of an infected aortic graft. ~>~9 Its long-term success should be measured in terms of persistent retroperitoneal infections that can develop even years after graft replacement. Late infectious complications most commonly arise in patients with primary graft infections caused by the less virulent micro-organism, for example coagulasenegative Staphylococcus epidermidis. 19 Hence the need for clinical and diagnostic imaging follow-up for reliable retroperitoneal surveillance. Newly introduced functional diagnostic techniques capable of detecting graft infections in their early stages, notably leukocytelabelled 99m HMPAO Technetium Scintigraphy (99mTc), seem to meet this requirement. 2°-22 We report a long-term follow-up (mean 37 months) of 18 patients, nine with an aortoenteric erosion (AEE)

Autogenous reconstruction with the lower extremity deep veins: an alternative treatment of prosthetic infection after reconstructive surgery for aortoiliac disease.

This report evaluates the efficiency of use of the lower extremity deep vein as arterial conduits in the autogenous repair of prosthetic infection after reconstructive aortoiliac surgery. We reviewed our records for the period 1990 to 1994 of all patients with prosthetic infection after reconstruction for aortoiliac disease, and we selected for this study all those patients who underwent autograft repair with the lower extremity deep veins. Included were 15 patients: 12 had previously undergone direct aorto(ilio)femoral reconstruction, and three had an extraanatomic prosthetic graft. Thirteen patients were admitted with primary graft infection, and two were admitted with secondary graft-enteric erosion. Treatment consisted of prosthetic excision and aorto(ilio)femoral reconstruction with the superficial femoral vein. In situ reconstruction was performed in 12 cases. The operative mortality rate was 7%. There were no early graft occlusions. One patient underwent an above-knee amputation because of concomitant femoropopliteal occlusion in the presence of a patent deep venous aortofemoral graft. Early postoperative limb swelling was common and was controlled with bed rest, elastic stockings, or intermittent pneumatic compression. The mean follow-up of this series was 17 months (range 4 to 33 months). Two patients died of unrelated causes. One graft occluded after 16 months. There were no reinfections, and all but one patient resumed normal daily activities. Disability from removal of the deep veins was minimal: only one patient continues to wear elastic stockings for limb swelling and shows signs of venous hypertension more than 2 years after surgery. Harvesting of the lower extremity deep veins is well tolerated. Autogenous reconstruction with these veins provides good potential for salvage of life and limbs in case of prosthetic infection. A longer period of follow-up is required to study the long-term behavior of these grafts and to allow definite comparison with more conventional approaches.

Fate of the exposed saphenous vein graft

Patients with functioning vein grafts may present with wound problems resulting in exposure of the graft. We reviewed the courses of 16 patients presenting with this problem to determine the causative factors and the most appropriate management of this therapeutic dilemma. Diabetes mellitus (11 of 16, 68.7%) and wound infection (12 of 16, 75%) were frequent pre-existing conditions associated with exposed venous grafts. All patients with exposed vein grafts were initially treated conservatively with regular application of moist sterile dressings, followed by split-thickness skin graft coverage of the wounds when clean. The wounds healed in 7 patients, whereas 9 patients developed complications of hemorrhage (7 patients) and graft thrombosis (2 patients). The outcome of therapy was highly dependent on the type of organism originally cultured from the wounds. The incidence of vein graft disruption was lowest when the wounds were sterile (25%) or when gram-positive bacteria grew (25%). Gram-negative infection uniformly resulted in disruption of the exposed venous graft. When a new graft was placed, the secondary graft became reinfected in all patients with gram-negative primary graft infection. There were no instances of secondary graft reinfection when gram-negative bacteria were not present. These data suggest that the outcome of patients presenting with exposed vein grafts is highly dependent on the bacterial flora of the process. Vein graft disruption is frequent in patients with gram-negative infection, suggesting that these patients should be treated with distant graft ligation and extra-anatomic bypass. By contrast, patients without gram-negative infection may be successfully managed with local wound care.

Primary graft infections

Primary graft infections

Primary graft infections

An amputation rate of 8% to 52% and a mortality rate of 13% to 58% make vascular prosthetic graft infections the most dreaded complication facing a vascular surgeon. In 1978 a randomized prospective double-blind study reported a statistically significant decrease in wound infections in patients treated with prophylactic antibiotics whereas the graft infection difference only approached statistical significance. The present study reviews 2614 arterial prosthetic grafts implanted from January 1975 through June 1986. Twenty-four patients were identified as having a prosthetic graft infection, yielding an overall infection rate of 0.92%. Staphylococcus aureus was the most common organism, occurring in one third of the cases. The most common graft material was polytetrafluoroethylene (PTFE) (33%) followed by Dacron (29%), composite PTFE and Dacron (20%), and umbilical vein grafts (9%). Diabetes was a common factor in one third of the patients. Symptoms of infection were present in 15 patients (63%) within 3 months of operation, with 11 patients showing symptoms within 30 days. The longest interval between operation and onset of symptoms was 48 months. Prophylactic antibiotics were administered to 22 of the 24 patients, but in only 7 of the 22 (29.5%) were they given according to our usual practice. All patients required removal of the infected prosthesis, with limb loss in 17% and death in 17%.

Descending thoracic aorta-to-femoral artery bypass.

Descending thoracic aorta-to-femoral artery grafts were placed in 13 patients who had abdominal aortas deemed undesirable for surgical treatment. These included seven patients in whom an infected aortic graft had been removed for primary graft infection (three) or aortoduodenal fistula (four). These patients had been treated initially with axillary-femoral grafts. In five other patients, this approach was used following failure of at least two previous aortofemoral grafts. The remaining patient was so treated following multiple complex abdominal operations. The surgical technique involves a posterolateral, seventh interspace thoracoabdominal incision with a transdiaphragmatic retroperitoneal tunnel to the left groin. There was no operative mortality. The mean follow-up of all patients was 22 months (range, one to 44 months). All grafts remained patent except one, which was removed because of ascending groin infection. Three patients died, at 24, 29, and 44 months postoperatively, respectively. Reasonable perioperative morbidity and reliable patency make this an attractive technique for the conversion of axillofemoral bypasses and, when reentry of the abdominal cavity is undesirable, laparotomy is avoided.

Management of Complications Following Dermis-Fat Grafting for Anophthalmic Socket Reconstruction

Sixty consecutive cases of dermis-fat grafts for anophthalmic socket reconstruction were reviewed to examine the frequency, severity, and management of postoperative complications. In seven patients, the conjuctiva failed to resurface the graft and central ulceration developed. Ten cases resulted in enophthalmos. Two patients developed keratinized sockets with chronic discharge and desquamation. Three patients required excision of conjunctival granulomas. One patient developed a primary graft infection. A donor site hematoma occurred in one patient. Secondary surgical intervention was required in ten patients. Nine complications in eight patients were managed in the office; five complications in four patients were observed and subsequently resolved without surgical intervention. Most complications occurred in patients with severely traumatized sockets who had undergone extensive earlier ocular surgery, or who had a systemic disease contributing to defective wound healing.