Improved results with conventional management of infrarenal aortic infection

Management and Clinical Outcome of Aortic Graft Infections: A Single-Center Retrospective Study

BACKGROUND

This study aimed to evaluate the outcome of various treatment options for aortic graft infection (AGI) patients and identify factors affecting their prognosis.

METHODS

The data of AGI patients from January 2008 to December 2019 were retrospectively collected and analyzed. The primary endpoints were 30-day mortality and perioperative complication-related morbidity; the secondary endpoints were re-infection (RI) rates, primary and secondary graft patency, overall mortality, duration of antibiotic therapy, and the number of antibiotic types used in treatment.

RESULTS

There was no significant difference in the 30-day mortality and perioperative-related complications between the conservative treatment, in-situ reconstruction (ISR), and extra-anatomic reconstruction (EAR) groups. The ISR group had lower re-infection rates and better overall survival rates than the EAR and conservative treatment groups. Different bypass graft conduits had no significant influence on the RI rate or primary and secondary graft patency. AGI patients infected with high-virulence pathogens had higher RI and overall mortality rates than those infected with low virulence pathogens, but this was not statistically significant. Initial procedures prior to the AGI also had no influence on the prognosis of AGI patients. Patients undergoing ISR or EAR surgery received antibiotic therapy for a longer duration than patients undergoing conservative treatment. Patients without RI received more types of antibiotics than patients with RI.

CONCLUSIONS

ISR had lower RI rates and better overall survival rates than EAR and conservative treatment and may be a better choice for patients with AGI. Several factors were found to have no influence on patients' prognosis however, further studies are required.

Infected Aortic Aneurysm Caused by Streptococcus zooepidemicus: A Case Report and Literature Review

A 66-year-old Japanese male working at a stable developed abdominal pain and fever and was brought to the emergency department. The computed tomography scan revealed an aneurysm of approximately 70 mm in diameter, with an irregular border, at the infrarenal abdominal aorta. Emergency surgery was performed with a bifurcated Dacron graft. Streptococcus zooepidemicus was observed on the aneurysm wall. He was discharged in good condition and was prescribed oral amoxicillin/clavulanic acid for 4 months. He has remained well and did not develop inflammation. Evaluation of patient history and data, including the consumption of unpasteurized dairy food, occupation, and direct contact with animals, is important for an early diagnosis, a prompt surgery, and an appropriate antibiotic therapy.

Mid-Term Outcome of Infected Abdominal Aortic Stent Graft Dismantlement with Reconstruction of Bilateral Axillofemoral Bypass

Background: Abdominal aortic stent graft infection (AAGI) is a severe complication. The optimal management of AAGI remains unclear. This study provides updated results of bilateral axillofemoral bypasses (AFBs) for patients with AAGI. Patients and Methods: In total, 31 patients (25 men; mean age, 67.1 years) with AAGI treated using AFB between January 2006 and April 2020 were included. Overall, the mean follow-up duration was 24 months (range, 1-72). In the 23 patients who survived the post-operative period, the mean follow-up duration was 32 months (range, 12-72). Results: Thirty-day and in-hospital mortality rates was 16% and 26%, respectively. The 12-month primary and secondary patency rates for the AFB graft were both 91%. In total, seven (30%) patients received re-interventions such as thrombectomy and balloon angioplasty. No amputation was required during follow-up. Culture results were positive in 87% of pre-operative cultures and 84% of intra-operative cultures. Staphylococcus aureus was the most prevalent pathogen, with four cases of methicillin-resistant Staphylococcus aureus and one each of vancomycin-resistant enterococci, carbapenem-resistant Klebsiella pneumoniae, and carbapenem-resistant Enterobacteriaceae. In-hospital mortality rate was 57% in patients with drug-resistant pathogens. Conclusions: Reconstruction with bilateral AFB and stent graft removal in patients with AAGI is a feasible treatment modality and provided an acceptable patency rate and low amputation rate. Additional studies investigating long-term results and the optimal treatment of AAGI are required.

Collagen-Based Tissue Engineering Strategies for Vascular Medicine

Cardiovascular diseases (CVDs) account for the 31% of total death per year, making them the first cause of death in the world. Atherosclerosis is at the root of the most life-threatening CVDs. Vascular bypass/replacement surgery is the primary therapy for patients with atherosclerosis. The use of polymeric grafts for this application is still burdened by high-rate failure, mostly caused by thrombosis and neointima hyperplasia at the implantation site. As a solution for these problems, the fast re-establishment of a functional endothelial cell (EC) layer has been proposed, representing a strategy of crucial importance to reduce these adverse outcomes. Implant modifications using molecules and growth factors with the aim of speeding up the re-endothelialization process has been proposed over the last years. Collagen, by virtue of several favorable properties, has been widely studied for its application in vascular graft enrichment, mainly as a coating for vascular graft luminal surface and as a drug delivery system for the release of pro-endothelialization factors. Collagen coatings provide receptor-ligand binding sites for ECs on the graft surface and, at the same time, act as biological sealants, effectively reducing graft porosity. The development of collagen-based drug delivery systems, in which small-molecule and protein-based drugs are immobilized within a collagen scaffold in order to control their release for biomedical applications, has been widely explored. These systems help in protecting the biological activity of the loaded molecules while slowing their diffusion from collagen scaffolds, providing optimal effects on the targeted vascular cells. Moreover, collagen-based vascular tissue engineering substitutes, despite not showing yet optimal mechanical properties for their use in the therapy, have shown a high potential as physiologically relevant models for the study of cardiovascular therapeutic drugs and diseases. In this review, the current state of the art about the use of collagen-based strategies, mainly as a coating material for the functionalization of vascular graft luminal surface, as a drug delivery system for the release of pro-endothelialization factors, and as physiologically relevant in vitro vascular models, and the future trend in this field of research will be presented and discussed.

A meta-analysis of outcomes of in-situ reconstruction after total or partial removal of infected abdominal aortic graft

INTRODUCTION

There is currently a lack of evidence for the relative effectiveness of partial resection (PR) and total resection (TR) before managing abdominal aortic graft infection (AGI). Most authorities agree that TR is mandatory for intracavitary AGI in patients with favorable conditions but there is an increasing number of patients with severe comorbidities for whom this approach is not suitable, resulting in a prohibitive mortality rate. The purpose of this study was to determine the most appropriate indication for TR or PR.

EVIDENCE ACQUISITION

A meta-analysis was conducted on the rates of early/late mortality, amputations and reinfection. A meta-regression was performed with eight variables: patient age, male prevalence, presence of virulent or nonvirulent organisms, urgency, omentoplasty and follow-up.

EVIDENCE SYNTHESIS

Twenty-one studies and 1052 patients were included. For TR and PR, the rates of early mortality and reinfection were 16.8% and 10.5%, 11% and 27%, respectively. For TR urgency and male gender were associated with increased rate of early mortality and male gender, PDF and virulent organisms were associated with increased risk of reinfection. For PR no statistical correlation was analyzable except for PDF with increased risk of reinfection.

CONCLUSIONS

Early mortality rates are higher for TR and reinfection rates are higher for PR. For TR early mortality increases in urgent cases and it is suggested that alternative option must be discussed, reinfection decreases in the presence of nonvirulent organisms and TR seems optimal. For TR and PR reinfection increases in presence of PDF and alternative technique may be more appropriate.

Current Evidence on Management of Aortic Stent-graft Infection: A Systematic Review and Meta-Analysis

BACKGROUND

Aortic stent-graft infection (SGI) is rare but remains one of the most challenging and threatening complications. This systematic review aimed to identify the clinical features, treatment, and outcomes of endograft infection after abdominal endovascular aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR).

METHODS

A systematic literature review of all published literature from January 1991 to September 2016 on SGI was performed under the instruction of Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Aorta, aneurysm, endovascular, stent-graft, endograft and infection were the keywords used in our comprehensive search in PubMed and MEDLINE databases. Data analysis was performed using SPSS, V 22.0.

RESULTS

A total of 185 potential relevant articles were identified, but only 11 studies with 402 patients met the inclusion criteria. Majority of the patients were male (308/402, 77%), with a mean age ranging from 65 to 73 years. Most of the endografts were implanted for EVAR (351/402, 87%), while the other 51 (13%) endografts were infected following TEVAR. Among the 402 patients, 39 (9.7%) patients presented with aortic rupture. Ninety-two of 380 (24.2%) patients with available data had aortoenteric fistula (AEF). Sixty-nine patients (17%) died in hospital or within 30 days after operation. One hundred fourteen patients (28%) died during follow-up. The most commonly used stent grafts were Zenith (Cook Inc, Bloomington, IN) (22%) and Excluder (W.L. Gore, Flagstaff, AZ) (20%). Of the 402 patients in this series, 108 patients (27%) had negative culture, and multiple microorganisms were identified in 103 patients (26%). The most frequently isolated microorganisms were Staphylcoccus species (30.1%), Streptococcus (14.8%), and fungus (9.2%). Forty-two patients (42/401, 10%) received conservative treatment, whereas 359 (90%) patients underwent surgical treatment, including stent graft removal with in situ reconstruction or extra-anatomical bypass, and secondary endovascular procedure. Patients in the surgical group had a higher survival rate compared with conservative group (58% vs. 33%, P = 0.002). The survival rate was higher in the patients with infected EVAR than TEVAR (58% vs. 27%, P = 0.000). Patient with AEF had a worse prognosis (survival rate 72% vs. 33%, P = 0.002).

CONCLUSIONS

Current evidence suggests that surgical treatment is a better option compared with conservative management in selected patients with aortic endograft infection. The outcome was worse in patients with infected TEVAR and AEF.

Spondylitis transmitted from infected aortic grafts: a review

Graft infection following aortic aneurysms repair is an uncommon but devastating complication; its incidence ranges from <1% to 6% (mean 4%), with an associated perioperative and overall mortality of 12% and 17.5-20%, respectively. The most common causative organisms are Staphylococcus aureus and Escherichia coli; causative bacteria typically arise from the skin or gastrointestinal tract. The pathogenetic mechanisms of aortic graft infections are mainly breaks in sterile technique during its implantation, superinfection during bacteremia from a variety of sources, severe intraperitoneal or retroperitoneal inflammation, inoculation of bacteria during postoperative percutaneous interventions to manage various types of endoleaks, and external injury of the vascular graft. Mechanical forces in direct relation to the device were implicated in fistula formation in 35% of cases of graft infection. Partial rupture and graft migration leading to gradual erosion of the bowel wall and aortoenteric fistulas have been reported in 30.8% of cases.

Rarely, infection via continuous tissues may affect the spine, resulting in spondylitis. Even though graft explantation and surgical debridement is usually the preferred course of action, comorbidities and increased perioperative risk may preclude patients from surgery and endorse a conservative approach as the treatment of choice. In contrast, conservative treatment is the treatment of choice for spondylitis; surgery may be indicated in approximately 8.5% of patients with neural compression or excessive spinal infection. To enhance the literature, we searched the related literature for published studies on continuous spondylitis from infected endovascular grafts aiming to summarize the pathogenesis and diagnosis, and to discuss the treatment and outcome of the patients with these rare and complex infections.

Bovine Pericardium as New Technical Option for In Situ Reconstruction of Aortic Graft Infection

BACKGROUND

Alloplastic aortic graft infection is a devastating complication following aortic surgery. It is associated with excessively high mortality and morbidity caused by anastomotic rupture or septicemia. Many authors consider in situ replacement after complete surgical graft removal as the method of choice. However, there is an ongoing debate about the most suitable material for reconstruction. We present our first experiences with replacing the descending and infrarenal aorta using custom-made bovine pericardium grafts.

MATERIAL AND METHODS

From January 2013 to 2015, 13 patients (10 male, median age 70 years, range 53-84) were treated for 5 early-graft infections after open reconstructions and 7 late graft infections (1 TEVAR, 2 EVAR, and 4 open reconstructions), and 1 patient was treated for mycotic aneurysm. Septicemia was evident in 8 patients, whereas 5 patients were presented with low-grade infection. In all cases, graft infection was proven by a synopsis of clinical findings, laboratory tests, imaging, and microbiologic tests (positive pathogen detection in 11 patients). Cutaneous and aortoenteric fistulae were present in 3 and 4 patients, respectively. All patients received an in situ replacement using a hand-sewn xenoprosthesis or patch made from a bovine pericardium sheet. Follow-up was routinely performed 3, 12, and 24 months after discharge.

RESULTS

For reconstruction, 4 pericardium tubes, 7 bifurcated grafts, and 2 large patches were implanted in situ. Technical success was 100%. Median length of hospital stay was 44 days (range, 20-136 days), with an in-hospital mortality rate of 7.7% (n = 1). Major procedure- and disease-related complications were temporary (n = 2) and permanent dialysis (n = 1), limb loss (n = 1), and long-term ventilation (n = 5). Complete infection control and initial healing could be achieved in 75% (n = 10). During the follow-up (median 9 months, range: 1-27 months), primary graft patency was 100%, and mortality was 41.7%. We observed 2 secondary ruptures due to reinfection at 4 and 7 months.

CONCLUSIONS

Custom-made bovine pericardium grafts provide a good option for in situ replacement following early or late aortic graft infection. Despite of its high biocompatibility, pericardium provides not an absolute protection against ongoing retroperitoneal infection. For the treatment, the principles of septic surgery need to be applied and close follow-up is mandatory.

Recurrent Aortoenteric Fistula: Two Different Bridge Solutions

A “recurrent” aortoenteric fistula (AEF) is very rare and in literature anecdotic. Currently, graft excision and extra-anatomic bypass are considered the treatments of choice, but are associated with significant mortality and morbidity. Herein, we describe the case of a “recurrent” AEF treated before definitive extra-anatomic bypass, by two different, staged bridge solutions: allograft in situ replacement and endovascular grafting. At 1, 3 and 6-month follow-up, the patient was asymptomatic and normally active.

Results from the Multicenter Study on Aortoenteric Fistulization After Stent Grafting of the Abdominal Aorta (MAEFISTO)

OBJECTIVE

This study investigated the frequency, clinical features, therapeutic options, and results of aortoenteric fistulas (AEFs) developing after endovascular abdominal aortic repair (EVAR).

METHODS

Eight Italian centers with an EVAR program participated in this retrospective multicenter study and collected data on AEFs that developed after a previous EVAR.

RESULTS

A total of 3932 patients underwent EVAR between 1997 and 2013 at the participating centers. During the same period, 32 patients presented with an AEF during EVAR follow-up, 21 with original EVAR performed for atherosclerotic aneurysmal disease (ATS group) and 11 with the original EVAR performed for a postsurgical pseudoaneurysm (PSA group). The incidence of AEF development after EVAR was 0.46% in the ATS group and 3.9% in the PSA group. Anastomotic PSA as the indication to EVAR (P < .0001) and urgent/emergency EVAR (P = .01) were significantly associated with AEF development. Median time between EVAR and the AEF diagnosis was 32 months (interquartile range, 11-75 months) for the ATS group and 14 months (interquartile range, 10.5-21.5 months) for the PSA group. Among five AEF patients treated conservatively, two (40%) died, at 7 and 15 months, and the remaining three were alive at a median follow-up of 12 months. The AEF was treated surgically in 27 patients, including aortic stent graft explantation in all cases, in situ aortic reconstruction in 14 (52%), and extra-anatomic bypass in 13 (48%). Perioperative mortality was 37% (10 of 27). No additional aortic-related death was recorded in operated-on patients at a median follow-up of 28 months.

CONCLUSIONS

Late AEFs rarely occur during EVAR follow-up, but the risk is significantly increased when EVAR is performed for PSA after previous aortic surgery and EVAR is performed as an emergency. Conservative and surgical treatment of post-EVAR AEF are both associated with high mortality. However, beyond the perioperative period, surgical correction of AEFs appears to be durable at midterm follow-up.

A Case of Primary Aortoenteric Fistula: Review of Therapeutic Challenges

BACKGROUNDS

Primary aortoenteric fistula (PAEF) is a lethal cause of gastrointestinal bleeding. They mainly originate from eroding abdominal aortic aneurysms into the intestinal wall. Other known causes involve malignancies, infection, corpora aliena, or radiation therapy. Traditional treatment consists of resection of the fistula and extra-anatomic reconstruction. In situ repair and endovascular stenting have offered new therapeutic options in managing this complex entity.

CASE REPORT

A 79-year-old woman presented with a PAEF. She was known with a 3.9-cm abdominal aortic aneurysm and polymyalgia rheumatica. The initial treatment consisted of endovascular stenting. Several months later, she presented with persistent inflammation of the aortic endoprosthesis. The prosthesis and inflammatory tissue were resected, and in situ reconstruction with autologous superficial femoral vein and omentoplasty was performed. Two years later, she remains well with no evidence for infection or bleeding.

CONCLUSIONS

Polymyalgia rheumatica might induce an AEF as in this patient no other provoking factors were retained. The different therapeutic options all have their advantages and disadvantages. In line with this case, we suggest an individualized approach for AEFs. In case of precarious hemodynamical state or life expectancy, endovascular treatment is indicated. Afterward, the possibility and/or necessity of open repair should be discussed. For stable patients with respectable life expectancy in situ repair with autologuous vein or rifampicin-soaked prosthesis (adjusted to comorbidities) might be most appropriate. Extra-anatomic reconstruction still remains a valuable alternative in older patients and in the presence of any other local factors hampering in situ reconstruction.

Management of infected vascular grafts

Infections of vascular grafts are associated with significant mortality and morbidity risk and cost an estimated $640 million annually in the United States. Clinical presentation varies by time elapsed from implantation and by surgical site. A thorough history and physical examination in conjunction with a variety of imaging modalities is often essential to diagnosis. For infected aortic grafts, there are several options for treatment, including graft excision with extra-anatomic bypass, in situ reconstruction, or reconstruction with the neo-aortoiliac system. The management of infected endovascular aortic grafts is similar. For infected peripheral bypasses, graft preservation techniques can be utilized, but in cases where it is not possible, graft removal and revascularization through uninfected tissue planes is necessary. Infected dialysis access can be surgically treated by complete or subtotal graft excision. Diagnosis, general management, and surgical approaches to infected vascular grafts are discussed in this review.

Conservative Treatment of an Infected Aortic Graft with Antibiotic Irrigation

Conservative management of an aortic graft infection is defined as "the nonresectional treatment of an aortic graft that has an established infection." Incidence of aortic graft infections is 0.5 to 5% and the estimated mortality rate from aortic graft infections ranges from 8 to 27%. We present the case of a 73-year-old male patient with an infected abdominal aortic graft following an emergency ruptured abdominal aortic aneurysm repair. Postemergency repair, he developed ischemic colitis with sigmoid colon perforation leading to fecal peritonitis and secondary sepsis. He developed a large infective collection within the aortic sac growing vancomycin-resistant enterococcus sensitive to linezolid. A percutaneous drain was placed in the aortic sac and this was irrigated with linezolid for a total of 28 days. The patient clinically improved. Overall, 7 months later, follow-up scan shows complete resolution of infection and the patient remains clinically stable. Conventional treatment of aortic graft infections involves an extra-anatomical bypass. Percutaneous drainage and antibiotic use may be used as bridging therapy for surgery or as definitive therapy when surgical treatment is impractical. Most aortic graft infections grow gram-positive cocci, the organisms form a biofilm which is protected from the external environment. Percutaneous drainage and antibiotic irrigation could possibly penetrate the biofilm and eradicate infection. Morris et al conducted a study on 10 patients having irrigation therapy and systemic antibiotic treatment and found a 1-year survival rate of 80%. In conclusion, conservative aortic graft treatment may be an effective alternative where surgical intervention is not suitable.

Strategies for managing aortoiliac occlusions: access, treatment and outcomes

Treatment of severe aortoiliac disease has dramatically evolved from a dependence on open aortobifemoral grafting to hybrid and endovascular only approaches. Open surgery has been the gold standard treatment of severe aortoiliac disease with excellent patency rates, but with increased length of stay and major complications. In contrast, endovascular interventions can successfully treat almost any lesion with decreased risk, compared to open surgery. Although primary patency rates remain inferior, secondary endovascular interventions are often minor procedures resulting in comparable long-term outcomes. The risks of renal insufficiency, embolization and access complications are not insignificant; however, most can be prevented or managed without significant clinical consequence. Endovascular therapies should be considered a first-line treatment option for all patients with aortoiliac disease, especially those with high-risk cardiovascular comorbidities.

Surgical and antimicrobial treatment of prosthetic vascular graft infections at different surgical sites: a retrospective study of treatment outcomes

Objective

Little is known about optimal management of prosthetic vascular graft infections, which are a rare but serious complication associated with graft implants. The goal of this study was to compare and characterize these infections with respect to the location of the graft and to identify factors associated with outcome.

Methods

This was a retrospective study over more than a decade at a tertiary care university hospital that has an established multidisciplinary approach to treating graft infections. Cases of possible prosthetic vascular graft infection were identified from the hospital's infectious diseases database and evaluated against strict diagnostic criteria. Patients were divided into groups according to the locations of their grafts: thoracic-aortic, abdominal-aortic, or peripheral-arterial. Statistical analyses included evaluation of patient and infection characteristics, time to treatment failure, and factors associated specifically with cure rates in aortic graft infections. The primary endpoint was cure at one year after diagnosis of the infection.

Results

Characterization of graft infections according to the graft location did show that these infections differ in terms of their characteristics and that the prognosis for treatment seems to be influenced by the location of the infection. Cure rate and all-cause mortality at one year were 87.5% and 12.5% in 24 patients with thoracic-aortic graft infections, 37.0% and 55.6% in 27 patients with abdominal-aortic graft infections, and 70.0% and 30.0% in 10 patients with peripheral-arterial graft infections. In uni- and multivariate analysis, the type of surgical intervention used in managing infections (graft retention versus graft replacement) did not affect primary outcome, whereas a rifampicin-based antimicrobial regimen was associated with a higher cure rate.

Conclusions

We recommend that future prospective studies differentiate prosthetic vascular graft infections according to the location of the grafts and that rifampicin-based antimicrobial regimens be evaluated in clinical trials involving vascular graft infections caused by staphylococci.

Femoral vein repair of arterial infections: technical tips to reduce procedure time

INTRODUCTION

Success with the neoaortoiliac system (NAIS) bypass has previously been reported. Drawbacks to this procedure include prolonged operative times and significant morbidity. The aim of this study was to evaluate whether a 2-team approach in addition to a consistent anastomosis technique reduces the operative time of the NAIS procedure.

METHODS

A single-center retrospective review was performed for operations using femoral vein in arterial reconstruction from 2003 to 2012.

RESULTS

A total of 40 patients, 25 men and 15 women, were included for analysis. Median operative time for all operations was 300 minutes (interquartile range). Thirty-day mortality was 7.5% (n = 3). Assisted primary patency at 1 year was 100%.

CONCLUSION

A 2-surgical team approach can reduce the operative time by up to 50%. This improves the attractiveness of this procedure, particularly when recalling that the treatment is definitive by virtue of its eradication of the source of infection.

Prevention and treatment of aortic graft infection

Prosthetic vascular graft infection remains one of the most challenging surgical problems for vascular surgeons. This condition is classically associated with high morbidity and mortality rates. Accurate diagnosis of a vascular graft infection can typically be made based on a thorough history and physical examination; although, infrequently, an extensive radiological evaluation is necessary to establish the clinical finding. Complete graft excision and extra-anatomic bypass grafting remains a commonly accepted surgical treatment strategy. Recent clinical data have supported other treatment modalities, including the use of in situ antibiotic-impregnated graft replacement, in situ allograft replacement and in situ autologous graft replacement. This article will review the pathobiology of aortic graft infection, as well as methods to prevent a prosthetic graft infection. Furthermore, various surgical treatment modalities of aortic graft infection will be discussed.

Contemporary management of infrarenal aortic graft infection: early and late results in 82 patients

Management of aortic graft infection (AGI) remains contentious. The purpose of this study was to evaluate factors of clinical significance which influence the outcome of different treatment modalities for AGI. From 2000 to 2008, 82 consecutive patients were treated for AGI. In situ reconstruction (ISR) was performed in 63 patients with various conduits, extra-anatomic reconstruction (EAR) in 11, conservative treatment in five and resection without reconstruction in three. The perioperative mortality rate for the series (33%) was similar for EAR and ISR and was higher in patients with secondary aortoenteric fistula ( P < 0.001) in those undergoing emergency aortic reconstruction ( P < 0.001) and in AGI caused by virulent organisms ( P < 0.05). Fifteen (27%) of the surviving patients developed a recurrence of infection (RI). EAR patients were more exposed to RI ( P < 0.04). In conclusion, ISR may be more appropriate for AGI, but this study cannot draw a conclusion relating to the optimal conduit for ISR.

Enxerto aorto bi-ilíaco com veia femoral superficial: uma opção nas infecções de próteses e endopróteses aórticas - relato de caso

Uma das complicações mais temidas na cirurgia vascular é a infecção do enxerto sintético. Afeta 2% dos procedimentos cirúrgicos convencionais e 0,3 a 6% dos procedimentos endovasculares. Relatamos o caso de paciente tratada de aneurisma de aorta abdominal por ambos os métodos e que, após seis anos, foi submetida a retirada das próteses devido à infecção. A veia femoral superficial bilateral foi usada como substituto, com sucesso.

Hybrid aortoiliac revascularization to avoid nonautogenous groin reconstruction in an intravenous drug abuser

Traditional methods for revascularization of an occluded aortoiliac system have necessitated either in-line aortic reconstruction through an aortobifemoral bypass or extra-anatomic bypass. However, both these approaches require artificial material to be placed in the groin. The consequence of groin infection can be devastating leading to high rates of both limb loss and mortality. One of the most feared patient populations presenting with groin complications is that of the intravenous drug abuser. We present the case of a patient with a long history of intravenous drug abuse with severe aortoiliac disease. Instead of resorting to a more traditional open surgical approach necessitating artificial reconstruction in the groin, we chose to proceed with a hybrid open and endovascular procedure through a direct open surgical access to the aortic bifurcation. This allowed for revascularization without the placement of artificial material in the groin.

The outcome of the axillofemoral bypass: a retrospective analysis of 45 patients

Purpose

This study was designed to retrospectively analyze outcomes of axillofemoral bypass (AxFB) operations performed in patients with severe comorbidities.

Methods

All patients (n = 45) who received an AxFB between 1990 and 2005 for aortoiliac occlusive disease (AIOD, n = 35) or infectious aortic disease (IAD, n = 10) were included. Information on patency of the bypass and mortality was retrieved from patient records. A Kaplan–Meier survival analysis was performed to illustrate survival rates, limb salvage, and primary and secondary patency.

Results

Included patients had several comorbidities and a high operative risk. In this group, a 30-day mortality rate of 20% was found: 17% for the AIOD group, and 30% for the IAD group. During 5-year follow-up 20 patients died, of which 15 during the first year after operation. Survival rates were at 64 and 41% at 1 and 5 years and limb salvage rates were 84% for both these years. Primary patency rates at 1 and 5 years were 72 and 58%, respectively, and secondary patency rates were 86% at both time points.

Conclusions

High mortality rates were found in AIOD or IAD patients who received an AxFB. However, for high-risk patients with an already reduced life expectancy, the AxFB remains an alternative with acceptable patency rates.

Infrarenal iterative aortic surgery: early and late morbi-mortality observed in 61 patients

The aim of this study was to analyze the early and late results of iterative aortic surgery after bypass of infrarenal aorta. Results from Clermont-Ferrand and Saint-Etienne hospitals have been collected. Between January 1993 and December 2001, 61 patients (59 men and two women, mean age 65 years) underwent a partial or complete second aortic reconstruction through a direct approach. Three different indications that required redo surgery were detected. Twenty-three patients presented with an infection (37%), 17 with an occlusive pathology (28%), and 21 with an aneurysm (34%). Medical or endoluminal treatment could no longer be considered. Mean period of time for redo surgery was 101 months (range 1-294). Eighteen of the procedures were emergency surgeries. A polyester prosthesis was used in 45 cases, an arterial allograft in 15 cases, and autogenous venous material in one case. In 22 cases (36%) a visceral, renal, or infracrural revascularization was associated. Four patients died (6.5%): three with an infection and one with an occlusive pathology. Global morbidity rate was 64%. Twelve vascular surgical complications (19%) required redo surgery: seven limb ischemia, three hemorrhage, and two colic ischemia. The preoperative factors generating severe complications were a septic context, renal insufficiency, and American Society of Anesthesiologists grade 3 or 4. Follow-up concerned the 57 surviving patients with a 43-month mean period of time (range 4-105). Actuarial survival rate was 80.7% at 3 years and could be compared to that observed after infrarenal aortic first surgery. Primary and secondary global patency rates were, respectively, 66.4 +/- 6.7% and 94.6 +/- 3% at 3 years with no major amputation. In our series including 37% of septic patients and nearly 30% of patients operated on in emergency, aortic iterative surgery led to mortality and morbidity rates twice and four times as important as those resulting from infrarenal aortic initial surgery, respectively. In the long term, patient survival and limb salvage rates were quite similar to those obtained with de novo surgery.

Efficacy of collagen silver-coated polyester and rifampin-soaked vascular grafts to resist infection from MRSA and Escherichia coli in a dog model

The primary objective of this study was to compare the efficacy of a collagen silver-coated polyester graft, InterGard, with a gelatin-sealed graft, Gelsoft, both soaked in rifampin, for resistance to direct bacterial contamination in an animal model. The second objective was to confirm the lack of inflammation from silver acetate. Vascular grafts, 6 mm in diameter, were implanted in the infrarenal aorta of 28 dogs. Intravenous cefamandole (20 mg/kg) was injected intraoperatively in all dogs. The dogs were divided into three groups. Group I included 12 dogs. Six dogs received silver grafts and six dogs received gelatin-sealed grafts, all soaked with rifampin. Grafts implanted in group I were directly infected with methicillin-resistant Staphylococcus aureus (MRSA). Group II included also six silver grafts and six gelatin-sealed grafts, all soaked with rifampin. Dogs of group II were directly infected with Escherichia coli. Group III comprised four dogs, which received gelatin unsealed grafts, directly infected with MRSA, the control group. All dogs were followed by regular clinical examination, including blood cultures. Grafts in groups I and III and in group II were harvested at 30 days and 10 days, respectively. Bacterial analyses were performed on the explanted grafts. Histology was performed on both the tissue samples and the anastomotic sites of the harvested grafts. In group I, no grafts were infected with MRSA, irrespective of graft type. In group II, no silver grafts were infected with E. coli, whereas one (16.6%) of six gelatin-sealed grafts was infected (p = 0.317). In group III, three (75%) of the four grafts were infected with MRSA. The infection rate in the silver grafts and the gelatin-sealed grafts soaked in rifampin in group I compared with the unsealed gelatin grafts in group III was statistically significantly different (p < 0.05). There was no statistically significant difference in the inflammation score, obtained by histological analysis, between rifampin-soaked silver and Gelsoft grafts in either group I or group II. There were signs of necrosis at the anastomoses in three (25%) gelsoft grafts of 12 in groups I and II. There were no clinical or biological signs of inflammation from use of silver-coated grafts. These results indicate that collagen silver-coated grafts and gelatin-sealed grafts, both soaked in rifampin, provide resistance against MRSA and E. coli. There was a trend toward better resistance but without statistical significance against E. coli from the rifampin silver graft compared with the rifampin-soaked Gelsoft graft, without signs of inflammation from InterGard silver grafts.

Prevention of Staphylococcus aureus graft infection by a new gelatin-sealed vascular graft prebonded with antibiotics

OBJECTIVE

The aim of this study was to evaluate the efficacy of a new gelatin-sealed graft prebonded with two antibiotics in resisting infection with Staphylococcus aureus (S aureus) A980142 after direct bacterial application in a dog model.

METHODS

Twelve 6.0-mm polyester grafts were implanted in dogs end-to-end into the infrarenal aorta. The dogs were divided into two groups. A test group (n = 6) received experimental antibiotic-bonded gelatin-sealed knitted polyester grafts, loaded with two antibiotics, rifampin and tobramycin. A control group (n = 6) received commercial gelatin-sealed knitted polyester grafts. At the end of graft implantation, 50 mul of a 1.8 x 10(4) CFU/mL S aureus solution were instilled directly over the graft. One week after implantation, grafts were harvested with sterile technique. Quantitative cultures were obtained from all the harvested grafts. The results were expressed as colony-forming units per cm(2) of surface of the graft. Bacteriological study was also performed on various tissue samples. The chi(2) test was used to compare the culture proven infection of control and antibiotics-bonded grafts.

RESULTS

Mean inoculum size was similar in the two groups of dogs. Five of the six control grafts grew S aureus A980142 at the time of graft removal, whereas none of the six antibiotic-bonded gelatin-sealed grafts were infected (P = .0192). None of the organ samples were infected in the group implanted with antibiotic-bonded grafts, whereas 15/34 samples grew S. aureus in the control group.

CONCLUSION

These results indicate that this gelatin sealed graft prebonded with two antibiotics resists infection caused by S aureus graft contamination in a dog model.