Prosthetic Graft Research Articles

Extra-Anatomical Bypass for Chronic Mesenteric Ischemia with Saphenous Vein Grafts from a Previous Axillofemoral Artery Bypass Graft: A Case Report

A 74-year-old woman who was diagnosed with chronic mesenteric ischemia was under hemodialysis maintenance and had previously undergone axillobifemoral bypass surgery because of abdominal aortoiliac occlusion. Endovascular and antegrade or retrograde surgical revascularizations from the aortoiliac artery were contraindicated because of a severely calcified arteriosclerotic lesion, which included aortoiliac occlusion. During median laparotomy, revascularization consisting of bypass grafting from a previous prosthetic graft to the mesenteric arteries was performed using saphenous vein grafts. Although extra-anatomical bypass for chronic mesenteric ischemia is challenging, it provides a feasible option in cases where conventional endovascular or surgical revascularization is contraindicated.

Management of infected arteriovenous grafts for haemodialysis: Outcomes and strategies using a novel objective scoring system.

In haemodialysis patients with exhausted autogenous options, prosthetic arteriovenous grafts (AVGs) are frequently utilised as tertiary vascular access. However, the prosthetic nature of AVGs precipitates an increased risk of infection which may translate to excess morbidity and life-threatening complications. The current evidence remains divided on the optimal treatment strategy for arteriovenous graft infections (AVGi) with arguments for conservative management by antibiotics, salvaging with graft revision or total/subtotal excision. To address this gap, we assessed the outcomes of AVGi patients treated in our institution, developing an AVGi severity classification model and a proposed treatment algorithm to guide AVGi management. We conducted a single centre retrospective review of outcomes of patients with AVGi managed either by sole antibiotics therapy, graft revision or surgical excision between June 2016 and May 2021. Outcomes of AVGi patients across differing treatment groups were compared, including 1-year mortality, 6-month and 1-year functional vascular access. We also analysed the outcomes of tunnelled haemodialysis lines (THL), which were used as a temporary vascular access in several AVGi patients in our study. A total of 34 AVGi patients were managed within that time frame and included in the study (5 conservatively management by antibiotics, 5 graft revisions and 24 surgical excision) with a mean age of 60.4 ± 14.4 years (67.6% males). Overall 1-year mortality was 14.7%. A 6-month functional vascular access status across the three groups stood at 60%, 60% and 10% while 1-year functional vascular access status was 60%, 75% and 42% respectively. When clinically appropriate, conservative management by antibiotics or salvage/graft revision can present as prudent AVGi treatment options. The adoption of our proposed severity classification system and treatment algorithm provides a more thorough objective assessment of the infection and helps guide the clinical decision-making process.

Pediatric Cranioplasty Patients With Hostile Reconstructive Environments: Split Calvarial Versus Prosthetic Implant.

Pediatric cranial defects can be preceded by prior infection, radiation therapy, failed prior cranioplasty, or cerebrospinal fluid leak, leading to a complex reconstructive environment. The primary aim of this study was to investigate differences in outcomes between pediatric patients with hostile reconstructive environments who received split-calvarial autologous grafts as opposed to prosthetic grafts in cranioplasty. We performed an institutional review board-approved retrospective chart review of 51 patients younger than 18 years who underwent cranioplasty with a hostile setting between 1998 and 2020. Patients were then stratified into prosthetic (45%) and autologous groups (54%). The primary outcome measured was postoperative complication, defined as requirement of a subsequent surgery or revision. Overall, there were no significant differences in age, sex, type of hostile setting, etiology of cranial defect, or side of the cranial defect between the 2 groups. Complication rate among the 2 graft groups was 18%. However, there were no significant differences in complications, defined as infection, failure or resorption of the graft, wound breakdown or necrosis, resulting bone defect, or hematoma, between the 2 populations. There was a significant difference in etiology between patients with complications, with patients who required a cranioplasty due to previous hemicraniectomy being nearly 5 times as likely to face a complication ( P = 0.045). In our study, there was no significant difference observed in complications between prosthetic and split-thickness autologous grafts in pediatric patients with hostile settings. It does, however, seem that patients who had a previous hemicraniectomy are more likely to face complications as a result of cranioplasty.

Fresh arterial allograft as a replacement for an infected common femoral prosthetic graft and recurrent false aneurysm.

Replacing an infected vascular prosthetic conduit with an allograft is a possible solution of this complication given the low recurrence of infection. It is most commonly utilized for cases where the use of autologous tissue is not an option. We present the case of a 70-year-old patient who had undergone repeated vascular reconstructions in the right lower limb. He was admitted to our department due to a progressively growing mass in the right groin and subsequently placed on the waiting list for a fresh allograft. The patient had the infected false aneurysm and prosthetic material of the femoral bifurcation replaced with an arterial allograft. The previous femoral popliteal autovenous bypass graft was reimplanted into the allograft. There were signs of sepsis during the operation; however, the blood culture was negative. Cultures from neither the wound nor the drain revealed the presence of any bacteria. The patient was discharged on the seventh post-operative day with prophylactic antibiotics. An early followup confirmed that there were no signs of recurrent infection and that the reconstruction remained patent. Seven and half months after the surgery, the femoral popliteal bypass graft became occluded and a conservative approach was chosen. A small thrombosed false aneurysm of the graft was revealed two years after the surgery due to transient non-compliance of the patient to immunosuppression therapy. It was treated conservatively. Two and a half years after the surgery, the allograft still remains open and the limb is preserved.

Staged autogenous to prosthetic hemodialysis access creation strategy to maximize forearm options

ObjectiveWhen an adequate cephalic vein is not available for fistula construction, surgeons often turn to basilic vein or prosthetic constructions. Single-stage forearm prosthetic hemodialysis accesses are associated with poor durability, and upper arm non-autogenous access options are often limited by axillary outflow failure, which inevitably drives transition to the contralateral arm or lower extremity. We hypothesized that initial creation of a modest flow proximal forearm arterial-venous anastomosis to dilate (“develop”) inflow and outflow vessels, followed by a planned second-stage procedure to create a cannulation zone with a prosthetic graft in the forearm, would result in reliable and durable hemodialysis access in patients with limited options. MethodsWe performed an institutional cohort study from 2017 to 2021 using a prospectively maintained database supplemented with adjudicated chart review. Patients without traditional autogenous hemodialysis access options in the forearm underwent an initial non-wrist arterial-venous anastomosis creation in the forearm as a first stage, followed by a second-stage interposition graft sewn to the existing inflow and venous outflow segments to create a useable cannulation zone in the forearm while leveraging vascular development. Outcomes included time from second-stage access creation to loss of primary and secondary patency, frequency of subsequent interventions, and perioperative complications. ResultsThe cohort included 23 patients; first-stage radial artery-based (74%) configurations were more common than brachial artery-based (26%). Mean age was 63 years (standard deviation, 14 years), and 65% were female. Median follow-up was 340 days (interquartile range [IQR], 169-701 days). Median time to cannulation from second-stage procedure was 28 days (IQR, 18-53 days). Primary, primary assisted, and secondary patency at 1 year was 16.7% (95% confidence interval [CI], 5.3%-45.8%), 34.6% (95% CI, 15.2%-66.2%), and 95.7% (95% CI, 81.3%-99.7%), respectively. Subsequent interventions occurred at a rate of 3.02 (IQR, 1.0-4.97) per person-year, with endovascular thrombectomy with or without angioplasty/stenting (70.9%) being the most common. There were no cases of steal syndrome. Infection occurred in two cases and were managed with antibiotics alone. ConclusionsFor patients without adequate distal autogenous access options, staged prosthetic graft placement in the forearm offers few short-term complications and excellent durability with active surveillance while strategically preserving the upper arm for future constructions.

Assessment of 3-Year Patency after Endoluminal versus Surgical Bypass Therapy for Complex Femoropopliteal Artery Disease

PurposeTo compare the 3-year clinical outcomes of endoluminal bypass with those of surgical bypass for complex femoropopliteal (FP) arterial lesions. Materials and MethodsIn this retrospective multicenter study, 530 patients with symptomatic peripheral artery disease (Rutherford classification 1–3, 66.0%; 4–6, 34.0%) who underwent either endoluminal bypass with Viabahn stent grafts (n = 276) or surgical bypass (n = 254) (with saphenous vein grafts, 74.4%; prosthetic grafts, 25.6%) for FP arterial lesions between 2010 and 2018 were analyzed. The propensity score-matched analysis was performed to compare the 3-year clinical outcomes of endoluminal bypass with those of surgical bypass. The primary end point was primary patency (freedom from restenosis). The secondary end points were secondary patency, freedom from target lesion revascularization (TLR), limb salvage, and overall survival. The interaction effect of baseline characteristics on the association of the revascularization strategy with the risk of restenosis was analyzed using the Poisson mixed-effect model. ResultsThe propensity score-matched analysis extracted 107 pairs. After propensity score matching, the primary patency rate at 1, 2, and 3 years was 84.5%, 75.1%, and 70.9%, respectively, for the endoluminal bypass group versus 78.6%, 73.3%, and 72.0%, respectively, for the surgical bypass group (P = .65). There was no significant difference in secondary patency, freedom from TLR, limb salvage, and overall survival (all P > .05). The subsequent interaction analysis revealed that the involvement of popliteal lesions, small distal reference vessel diameters, and long lesions favored surgical bypass over endoluminal bypass because of improved primary patency (all P for interaction < .05). ConclusionsThe 3-year clinical outcomes after endoluminal bypass or surgical bypass for FP arterial lesions were similar.

Methicillin-Susceptible Staphylococcus aureus Biofilm Formation on Vascular Grafts: an In Vitro Study.

The aim of this study was to quantify in vitro biofilm formation by methicillin-susceptible Staphylococcus aureus (MSSA) on the surfaces of different types of commonly used vascular grafts. We performed an in vitro study with two clinical strains of MSSA (MSSA2 and MSSA6) and nine vascular grafts: Dacron (Hemagard), Dacron-heparin (Intergard heparin), Dacron-silver (Intergard Silver), Dacron-silver-triclosan (Intergard Synergy), Dacron-gelatin (Gelsoft Plus), Dacron plus polytetrafluoroethylene (Fusion), polytetrafluoroethylene (Propaten; Gore), Omniflow II, and bovine pericardium (XenoSure). Biofilm formation was induced in two phases: an initial 90-minute adherence phase and a 24-hour growth phase. Quantitative cultures were performed, and the results were expressed as log10 CFU per milliliter. The Dacron-silver-triclosan graft and Omniflow II were associated with the least biofilm formation by both MSSA2 and MSSA6. MSSA2 did not form a biofilm on the Dacron-silver-triclosan graft (0 CFU/mL), and the mean count on the Omniflow II graft was 3.89 CFU/mL (standard deviation [SD] 2.10). The mean count for the other grafts was 7.01 CFU/mL (SD 0.82). MSSA6 formed a biofilm on both grafts, with 2.42 CFU/mL (SD 2.44) on the Dacron-silver-triclosan graft and 3.62 CFU/mL (SD 2.21) on the Omniflow II. The mean biofilm growth on the remaining grafts was 7.33 CFU/mL (SD 0.28). The differences in biofilm formation on the Dacron-silver-triclosan and Omniflow II grafts compared to the other tested grafts were statistically significant. Our findings suggest that of the vascular grafts we studied, the Dacron-silver-triclosan and Omniflow II grafts might prevent biofilm formation by MSSA. Although further studies are needed, these grafts seem to be good candidates for clinical use in vascular surgeries at high risk of infections due to this microorganism. IMPORTANCE The Dacron silver-triclosan and Omniflow II vascular grafts showed the greatest resistance to in vitro methicillin-susceptible Staphylococcus aureus biofilm formation compared to other vascular grafts. These findings could allow us to choose the most resistant to infection prosthetic graft.

Treatment of infected thoracic aortic aneurysm with combined abscess debridement and stent-graft wrapping using pedicled latissimus dorsi muscle flaps after thoracic endovascular aortic repair

BackgroundOpen thoracic surgery (with infected lesion removal, prosthetic graft replacement, and pedicled tissue flap) has remained the main treatment for infected thoracic aortic aneurysms to date. Recent reports have highlighted good prognostic outcomes with thoracic endovascular aortic repair. However, thoracic endovascular aortic repair for infected thoracic aortic aneurysms is associated with an exacerbation of infection due to residual infected tissues. We discuss the control of refractory infections following endovascular treatment of infected thoracic aortic aneurysms.Case presentationAn 81-year-old man, with a history of insulin-dependent diabetes mellitus and pancreaticoduodenectomy, presented to our emergency department with a fever. Blood tests revealed a markedly elevated leukocyte count, and contrast-enhanced computed tomography suggested a descending thoracic aortic pseudoaneurysm. We diagnosed the patient with an infected descending thoracic aortic aneurysm, and performed urgent thoracic endovascular aortic repair; he was started on an intravenous antibiotic treatment. Postoperatively, blood tests revealed a decreased leukocyte count and the patient remained afebrile. However, computed tomography revealed temporal enlargement of the abscess cavity; therefore, an abscess debridement and stent graft wrapping with pedicled latissimus dorsi muscle flaps were performed, which successfully controlled the infection. Six weeks after abscess debridement, the patient was switched to an oral antibiotic therapy. There was no evidence of recurrence of infection 8 months after the surgery.ConclusionsA combined abscess debridement and pedicled tissue flap approach is useful for patients with poor surgical tolerance in whom infection control is difficult after thoracic endovascular aortic repair for infected thoracic aortic aneurysms. Pedicled latissimus dorsi muscle flaps are useful when using the omentum for pedicled tissue flap is difficult.

Surgical creation of upper extremity arteriovenous fistula and grafts: a narrative review.

Surgical creation of arteriovenous fistulas (AVF) and grafts (AVG) continues to be the mainstay access for hemodialysis (HD). Avoidance of dependence on dialysis catheters continues to be a worldwide mission in dialysis access. Importantly, there is no one-size-fits-all approach to hemodialysis access and each patient should undergo access creation that is patient-centered. The aim of this paper is to review the literature, current guidelines, and discuss the common types of upper extremity hemodialysis access and their reported outcomes. We will also share our institutional experience regarding the surgical creation of upper extremity hemodialysis access. The literature review incorporates twenty-seven relevant articles from 1997 to present and one case report series from 1966. Sources were gathered from electronic databases including PubMed, EMBASE, Medline, and Google Scholar. Only articles written in the English language were considered and study designs varied from current clinical guidelines, systematic and meta-analyses, randomized controlled trials, observational studies, and two main vascular surgery textbooks. This review exclusively focuses on the surgical creation of upper extremity hemodialysis accesses. Creating a graft versus fistula ultimately is decided by the existing anatomy, and is centered around the need of the patient. Preoperatively, the patient should undergo a thorough history and physical exam, with special attention to any previous central venous access, as well as, delineating the vascular anatomy with ultrasound imaging. The major tenets of access creation are choosing the most distal site of the non-dominant upper extremity whenever possible; and ideally creation of an autogenous access is preferred over a prosthetic graft. Described in this review are multiple surgical approaches for upper extremity hemodialysis access creation and associated institutional practices performed by the surgeon author. In the postoperative period, follow up care and surveillance are imperative to preserve a functioning access. The most recent guidelines regarding hemodialysis access still favor arteriovenous fistula as the primary goal for patients with suitable anatomy. Preoperative evaluation including patient education, intraoperative ultrasound assessment, meticulous technique, and careful postoperative management are all paramount for successful access surgery. Dialysis access remains quite challenging, but with diligence the great majority of patients can be dialyzed without catheter dependence.

Inflammatory popliteal aneurysm associated with SARS-CoV-2 infection.

SARS-CoV-2 infection involves the phase of viral replication and inflammatory response predicting the severity of COVID-19. Vascular involvement in SARS-CoV-2 infection has been well established. Thrombotic complications are common, while only few cases of dilatative diseases have been reported. We herein report the case of a 65-year-old male patient with an inflammatory 25-mm saccular popliteal artery aneurysm detected six months after symptomatic COVID-19 (pneumonia, and pulmonary embolism). The popliteal aneurysm was surgically managed with aneurysmectomy, and reversed bifurcated vein graft. Histological examination detected the infiltration of monocytes and lymphoid cells into the arterial wall. Popliteal aneurysm could be related to inflammatory response related to SARS-CoV-2 infection. The aneurysmal disease should be considered mycotic and surgically managed without prosthetic grafts.

Exogenous Testosterone Replacement Therapy Is Associated With Increased Risk For Arterial Graft Infections

Prosthetic graft infections are a major source of morbidity following vascular bypass surgery. Recent urologic data suggests that hypogonadal men and low testosterone may infer an increased risk for infection of prosthetic implants. We designed this study to evaluate the relationship between hypogonadism, testosterone replacement therapy (TRT) and vascular graft infections.

Open surgical replacement of the descending aorta: single-center experience.

This study presents a single center's experience and analyzes clinical outcomes following elective open surgical descending aortic replacement. Between January 2000 and August 2019, 96 patients with mean age 64 years (range, 49.5-71 years) (62.5% (n=60) male) underwent elective descending aortic replacement due to aneurysm (n=60) or chronic dissection (n=36). Marfan syndrome was present in 12 patients (12.5%). In-hospital mortality rate was 3.1% (n= 3. 2 in the aneurysm group, 1 in the dissection group). New-onset renal insufficiency postoperatively with (creatinine ≥ 2.5 mg/dl) manifested in 10 patients (10.8%). One patient (1%) suffered from stroke, and paraplegia developed in 1 pts (1%). The median follow-up time was 7 years (IQR: 2.5-13 years). The 5- and 10-year survival rates were 70.8% and 50.7% respectively. We did not observe any early or late prosthetic graft infection. The Cox proportional hazards regression analysis identified age (HR: 1.044, 95% CI: 1.009-1.080, p-value: 0.014), diabetes (HR: 2.544, 95% CI: 1.009-6.413, p-value: 0.048), and chronic obstructive pulmonary disease (COPD) (HR: 2.259, 95% CI: 1.044-4.890, p-value: 0.039) as risk factors for late mortality. This study showed that the elective open surgical replacement of the descending aorta can be achieved with excellent outcomes in terms of perioperative mortality and morbidity. Prosthetic graft is not a problem with open surgical descending aortic replacement, even in the long term. The online version contains supplementary material available at 10.1007/s12055-022-01443-x.

Peri-operative infection after pancreatectomy with prosthetic graft vein reconstruction

Background: Continued advancements in chemotherapeutic regimens for pancreatic cancer renders more patients who would have previously been deemed unresectable to become surgical candidates. It is increasingly more common to perform curative-intent pancreatic resections with concurrent vascular resections in the setting of an anticipated vascular defect amenable to reconstruction. There are many possible conduits for vascular reconstruction, including autologous, cadaveric, and prosthetic. A cited concern using prosthetic grafts for vascular reconstruction is infection in a contaminated field. We present infectious outcomes in two patients from our experience using prosthetic interposition grafts for vascular resection.

The evolution of dialysis access surgery over 38 years: One surgeon's perspective.

The surgery for dialysis access has changed over the past 38 years. In the 1980s and 1990s, prosthetic grafts were the most common form of access. Then, autogenous fistulae had a rebirth due to their durability and decreased complications. The continued expansion of the dialysis population, coupled with the paucity of adequate superficial veins in many patients, required other techniques of dialysis access such as tunneled dialysis catheters, and more complex surgery on deeper veins. This study of one surgeon's practice over 38 years mirrors the extensive changes in dialysis access. The changes in surgical technique, interventional procedures, and approaches were documented and evaluated. During the 38-year period, there were 1531 autogenous fistulae, 409 prosthetic grafts, and 1624 tunneled dialysis catheters placed for access. The first 20 years had 130 autogenous fistulae with 302 prosthetic grafts, while in the last 10 years there were 740 fistulae and only 17 prosthetic grafts. Prosthetic grafts were not salvageable for a long term with exposure, infection, and persistent bleeding. Autogenous fistulae were best salvaged with autogenous tissue rather than prosthetic material. Interventional procedures were most valuable in stenting high-grade stenosis centrally and dilating areas of recurrent stenosis. They were not helpful in treatment of large aneurysms or as a long-term solution for persistent and/or massive bleeding. Dialysis access has progressed back to autogenous fistula. This may require longer use of tunneled dialysis catheters, and more surgical procedures, but the construction of an autogenous fistula can be achieved in many dialysis patients.

Bilateral rectus femoris myocutaneous flaps to salvage exposed axillo-bifemoral graft of bilateral groins

Exposed prosthetic grafts are a challenge to vascular specialists. Groin dissections in vascular surgery can lead to local tissue breakdown, especially in patients who have multiple comorbidities and poor nutritional status. In this report, we describe a patient with exposed prosthetic bypass conduits in the groin region which was successfully covered with bilateral myocutaneous flaps. A 75-year-old Sri Lankan male with diabetes, hypertension and Parkinson's disease presented with bilateral non-healing wound and rest pain for 3 months. Since his premorbid status precluded the aortic cross-clamping and aorto-bifemoral graft, a decision was made to perform a right axillo-bifemoral bypass using a prosthetic graft. Re-operation was required for graft thrombectomy on the same day of surgery. His post-operative period was complicated with lymph leak and surgical site infection of bilateral groin wounds which ultimately led to exposed prosthetic graft which was fortunately patent. After optimizing his nutritional status and comorbidities, he underwent bilateral rectus femoris myocutaneous flaps to cover the soft-tissue defect over the exposed prosthetic grafts. His initial post-operative period was unremarkable except for a small area of skin breakdown. Myocutaneous flaps are preferred as they are more resilient to breakdown compared to facio-cutaneous flaps, especially in a patient with compromised blood supply. The type of loco-regional flap should be carefully selected in an individualized manner depending on the regional vascularity. The rectus femoris flap is a suitable option in terms of ease of surgical technique and durability. Comorbidities and local factors should be optimized prior to definitive reconstruction to maximize the chances for optimal wound healing.

Clinical outcomes of in situ graft reconstruction in treating infected abdominal aortic stent grafts following endovascular aortic aneurysm repair: a single-center experience.

This study aimed to review our experience with the explantation of infected endovascular aneurysm repair (EVAR) grafts. This single-center, retrospective, observational study analyzed the data of 12 consecutive patients who underwent infected aortic stent graft explantation following EVAR between January 1, 2010 and December 31, 2019, of which 11 underwent in situ graft reconstruction following graft removal. The presentation symptoms, infection route, original pathology of abdominal aortic aneurysms (AAA), graft materials, and clinical outcomes were analyzed. Six patients underwent total explantation, whereas 5 underwent removal of only the fabric portions. For in situ reconstructions, prosthetic grafts and banked allografts were used in 8 and 3 patients, respectively. Four mechanisms of graft infection were noted in 11 patients: 4 had bacteremia from systemic infections, 3 had persistent infections following EVAR of primary infected AAA, 3 had ascending infections from adjacent abscesses, and 1 had an aneurysm sac erosion resulting in an aortoenteric fistula. No infection-related postoperative complications or reinfections occurred during the mean 65.27-month (standard deviation, ±52.51) follow-up period. One patient died postoperatively because of the rupture of the proximal aortic wall pseudoaneurysm that had occurred during forceful bare stent removal. Regardless of graft material, in situ graft reconstruction is safe for interposition in treating an infected aortic stent graft following EVAR. In our experience, the residual bare stent is no longer a risk factor for reinfection. Therefore, it is important not to injure the proximal aortic wall when removing the bare stent by force.

Open surgical repair of common femoral artery aneurysm

Common femoral artery (CFA) aneurysms are rare with an unknown exact incidence and often found in elderly males with chronic diseases. Early recommendations are to repair aneurysms with a maximum diameter of ≥2.5cm. We present the case of a 37-year-old male with a right CFA aneurysm. Open surgical repair (OSR) consisting of aneurysmectomy and reconstruction of the femoral artery with a bifurcated prosthetic graft was applied. Our study details this case and thoroughly reviews on the treatment of femoral artery aneurysms in the literature. OSR and vascular reconstruction with interposition prosthetic graft were durable and associated with favorable outcomes.

Ressecção cirúrgica de leiomiossarcoma de veia cava inferior retro-hepática sem reconstrução vascular: relato de caso

Abstract Inferior vena cava leiomyosarcoma (IVCL) is a rare malignant mesenchymal tumor. Surgical treatment is a challenge because it must combine free surgical margins with vascular reconstruction, using prosthetic or autologous grafts, primary suture, or simple ligation without vein reconstruction. The ligation option is possible thanks to the slow growth of the tumor, allowing collateral venous circulation to develop. We present a case of an IVCL treated with radical resection without vascular reconstruction. The patient was a 48-year-old female with abdominal pain in the right upper quadrant, asthenia, and postprandial dyspeptic symptoms. Abdominal tomography revealed a mass with an expansive formation located in the infrahepatic segment of the inferior vena cava and reduced vessel lumen. During surgery, vein clamping did not provoke hemodynamic repercussions, suggesting sufficient collateral circulation formation. It was decided to perform a radical resection of the entire portion of the retrohepatic vena cava and ligate the vena cava without vascular reconstruction. The patient recovered without complications.

Decrease of Graft Failure Rate by Improving Tactics and Surgical Techniques in Extraanatomic Bypass Operations

We analized the early and late postoperative complications that occurred after 693 bypass operations (574 anatomic and 119 extra-anatomic) performed in 10 consecutive years (1997-2006). The bypass graft failures (infection + thrombosis) treatment and the subsequent evolution of the patients were detected by analyzing patients’ readmissions made to solve these major post-bypass complications. The follow-up period extended up to 12 years after the primary arterial bypass reconstruction. In this period we registered: 89 secondary arterial reconstructions for early and late graft thrombosis; 8 healings after removal of the infected prostheses, followed by extraanatomic bypass operations (7 obturator bypass + 1 axillo-bifemoral bypass). The most frequent vascular prosthesis infection sites were the Scarpa triangle and the thoraco-abdominal subcutaneous segment of the axillo(bi)-femoral graft. Major amputations after extraanatomic bypass operations: at 4 years postoperatively for axillo(bi)-femoral operations the amputation rate was 17.6%, while for crossover operations it was 7.5%. Perioperatory mortality after anatomic bypass operations = 2 intraoperatory and 8 postoperatory (1.38%/574 operations); perioperatory mortality after extraanatomic bypass operations: 2 postoperatory deaths (1.68%/119 operations), 1 after axillo-femoral prosthesis infection and 1 after acute myocardial infarction. In order to reduce the graft major complication rate after extraanatomic bypass operations we took the following measures: 1. When there are arterial occlusive lesions distal to the femoral tripod we ensured an adequate outflow which favores the long-term patency of the extraanatomic graft; this goal was obtained by 2 methods: by enlargement profundoplasty and/or by performing an additional distal bypass towards the popliteal artery or towards the subgenicular arteries. The distal subgenicular anastomosis was made between a venous graft and the distal outflow artery for reducing the intimal hyperplasia. 2. For crossover bypass operations we often used autologous vein grafts; 3. In crossover ilio-femoral bypass operation with venous graft we avoid the graft compression in its path through abdominal wall by passing the graft through a stable caliber hole made in a polypropylene closure mesh of the abdominal wall. 4. We promote the tunneling of the axillo-femoral prosthesis through the subaponeurotic muscular tissue because this tissue better protects the prosthetic graft against infection. 5. In order to reduce the groin prosthesis infections, we prefer performing ilio-femoral crossover bypass instead of femoro-femoral one. 6. The obturator bypass remains a valuable tratment for groin infected prosthesis.

破裂性腹部大動脈瘤に対するdamage control surgeryの必要性が示唆された1例(Case of resuscitation from ruptured abdominal aortic aneurysm: necessity of damage control surgery)

要旨症例は87歳の男性。背部痛を主訴に前医へ救急搬送され，腹部大動脈瘤破裂の診断となった。当院への転院搬送中に心停止となったが，心肺蘇生を行い自己心拍再開して当院に到着した。直接手術室へ入室し，手術を開始した。入室時に再度心停止となったが，ステント拡張用のバルーンカテーテルで遮断を試みながら心肺蘇生を継続することで自己心拍再開した。前医で撮影された造影CT解析の結果，ステントグラフト内挿術の解剖学的条件を満たさず，開腹手術の方針とした。人工血管置換術は完遂したが，大量出血および低体温を原因とした凝固能破綻による静脈出血がコントロールできず，damage control surgery（DCS）に準じて早期の手術終了を図る方針としてガーゼパッキング後に閉腹した。術後2日目にガーゼ除去および閉腹術に臨んだが，開腹するとS状結腸から直腸にかけての壊死を認めたため，壊死腸管切除および横行結腸人工肛門造設術を施行した。その後の全身管理には難渋したが，術後294日で退院となった。近年，外傷外科領域ではDCSの考え方が重要視されているが，腹部大動脈瘤破裂を扱う心臓血管外科領域においてはその考え方が浸透しているとは言い難い。腹部大動脈瘤破裂を扱う心臓血管外科医もDCSを念頭においた計画を立てて手術を始めることが，救命率向上のためには重要である。