The weight of obesity in patients with lower extremity vascular injuries.

OBJECTIVE: Clinical obesity is an epidemic problem in the United States. The impact of this disease upon traumatic lower extremity vascular injuries (LEVI) is as yet undefined. We hypothesized that clinical obesity adversely affects outcome in patients with traumatic LEVI. METHODS: All adult patients admitted over a 5-year period with a traumatic LEVI were identified. Clinical obesity was defined as body mass index (BMI)>30. Obese and non-obese patient groups were compared for surgical management and outcome. RESULTS: A total of 145 patients were identified. BMI data were available for 115 (79.3%) of these patients (obese n=47; non-obese n=68). Obese and non-obese groups were similar. Obese patients underwent more vascular repairs but the amputation rate and mortality were not significantly different. CONCLUSIONS: While obese body habitus can increase the complexity of evaluation and management of patients with LEVI, we have demonstrated that equivalent outcomes to the non-obese population can be achieved for the clinically obese patient with a BMI>30. However, patients with a BMI>40 did reveal a significantly higher chance of amputation and death after LEVI. Due to the small number of patients in this subset, one should use caution when interpreting this data.

Popliteal artery injuries in an urban trauma center with a rural catchment area: do delays in definitive treatment affect amputation?

Extended length of time from injury to definitive vascular repair is considered to be a predictor of amputation in patients with popliteal artery injuries. In an urban trauma center with a rural catchment area, logistical issues frequently result in treatment delays, which may affect limb salvage after vascular trauma. We examined how known risk factors for amputation after popliteal trauma are affected in a more rural environment, where patients often experience delays in definitive surgical treatment. All adult patients admitted to the Level I trauma center, the University of Mississippi Medical Center, with a popliteal artery injury between January 2000 and December of 2007 were identified. Demographic information management and outcome data were collected. Body mass index, mangled extremity severity score (MESS), Guistilo open fracture score, injury severity score, and time from injury to vascular repair were examined. Fifty-one patients with popliteal artery injuries (53% blunt and 47% penetrating) were identified, all undergoing operative repair. There were nine amputations (17.6%) and one death. Patients requiring amputation had a higher MESS, 7.8 versus 5.3 (P < 0.01), and length of stay, 43 versus 15 days (P < 0.01), compared with those with successful limb salvage. Body mass index, injury severity score, Guistilo open fracture score, or time from injury to repair were not different between the two groups. Patients with a blunt mechanism of injury had a slightly higher amputation rate compared with those with penetrating trauma, 25.9 per cent versus 8.3 per cent (P = non significant). MESS, though not perfect, is the best predictor of amputation in patients with popliteal artery injuries. Morbid obesity is not a significant predictor for amputation in patients with popliteal artery injuries. Time from injury to repair of greater than 6 hours was not predictive of amputation. This study further demonstrates that a single scoring system should be used with caution when determining the need for lower extremity amputation.

Emergency procedures on the descending thoracic aorta in the endovascular era.

BACKGROUND: Thoracic endovascular aortic repair (TEVAR), initially developed for the treatment of degenerative aneurysms of the descending thoracic aorta, has been applied to the entire spectrum of descending thoracic aortic pathology in both the elective and emergent settings. This single center study evaluates the effectiveness of TEVAR for the treatment of acute surgical emergencies involving the descending thoracic aorta, including traumatic aortic disruption (TAD), ruptured descending thoracic aneurysm (RDTA), and acute complicated Type B dissection (cTBD). METHODS: A retrospective review of the medical records of all patients undergoing emergent TEVAR at the University of Mississippi Medical Center between August 2007 and November 2010 was undertaken. Patients were studied for 30-day survival, complications, type of device used for the repair, and technical aspects of the procedure. RESULTS: A total of 44 patients (59% male) with an average age of 49 years (range, 16-87 years) underwent emergent TEVAR during the study period. The technical success rate was 100%, with no patient requiring emergent open surgery for conditions involving the descending thoracic aorta at our institution during the study period. The majority (73%) of the repairs were accomplished using commercially available thoracic stent grafts. Abdominal endograft proximal extension cuffs were used in 12 (38%) of the 32 patients undergoing repair of TAD. Twenty-one patients (48%) required coverage of the left subclavian artery, two (10%) of whom subsequently required subclavian artery revascularization. Procedure-related complications included two strokes, one spinal cord ischemia, one unintentional coverage of the left carotid artery, one episode of acute renal failure, and three access site injuries. One patient undergoing repair of TAD had collapse of the stent graft in the early postoperative period. He was successfully treated by placement of an additional stent graft. Seven patients (16%) died within 30 days of surgery. Three of the deaths occurred in patients who had successfully undergone repair of a TAD and died of associated injuries. CONCLUSIONS: Emergent TEVAR has become the treatment of choice for acute surgical emergencies involving the descending thoracic aorta. Short-term morbidity and mortality compare favorably with historic results for emergent open surgical procedures on the descending thoracic aorta. Survival is highest in patients undergoing repair of TAD. Using current endograft technology, nearly all emergent conditions of the descending thoracic aorta can be successfully treated with TEVAR.

Infrarenal origin of the superior mesenteric artery: implications in endovascular repair of abdominal aortic aneurysm.

Endovascular aneurysm repair (EVAR) has become the preferred modality for the treatment of infrarenal abdominal aortic aneurysms (AAAs). A variety of anatomic factors must be considered when planning EVAR, including the relationship of the visceral arteries to the aneurysmal segment of the aorta. This report describes 2 patients with infrarenal AAA in whom the superior mesenteric artery was the most caudal visceral vessel, originating inferior to the renal arteries.

Endovascular repair of a chronic aortocaval fistula using a thoracic aortic endoprosthesis.

Penetrating abdominal trauma with injury to the aorta and vena cava usually requires emergent intervention and is frequently lethal. Formation of a chronic aortocaval fistula (ACF) is an uncommon late complication of these injuries. We report a case of an ACF presenting 17 years after a gunshot wound to the abdomen, with progressive congestive heart failure as the presenting symptom. The ACF was successfully treated with an endoprosthesis designed for the thoracic aorta.

Efficacy and safety results with the LifeSite hemodialysis access system versus the Tesio-Cath hemodialysis catheter at 12 months.

PURPOSE: To compare the performance and safety of a fully subcutaneous vascular access device, the LifeSite hemodialysis access system, versus a tunneled hemodialysis catheter, the Tesio-Cath, at 1 year after implantation. MATERIALS AND METHODS: Sixty-eight patients who required hemodialysis received implantation of the LifeSite device or a Tesio-Cath device as a part of this multicenter study. Thirty-four patients were treated in each group. The endpoints observed included blood flow rates and associated venous pressures, overall and device-related adverse events, the need for thrombolytic infusions, device-related infections (DRIs) and associated hospitalizations, and technical device survival. RESULTS: During the 12-month observation period, significantly higher venous pressures were required in patients with the Tesio-Cath to achieve blood flow rates comparable with those achieved with the LifeSite device. Patients in the LifeSite group experienced a significantly lower rate of non-device-related adverse events (P < .001), device-related adverse events (P < .016), need for thrombolytic infusions (P < .002), and DRIs (P < .013) compared with patients in the Tesio-Cath group. There was a trend toward a lower number of hospital days per month for DRIs in the LifeSite group, with the rate for the Tesio-Cath group being twice that in the LifeSite group. The use of the LifeSite device was also associated with a significantly higher probability of device survival for 12 months after censoring for planned removals (P < .031). CONCLUSIONS: The results of the present study demonstrate superior device performance and technical device survival, reduced complications, and the need for fewer interventions with the LifeSite hemodialysis access system compared with a standard hemodialysis catheter during a 1-year time period after implantation.

Multicenter clinical trial results with the LifeSite hemodialysis access system.

BACKGROUND: The LifeSite Hemodialysis Access System is a subcutaneous access device designed to maximize blood flow while minimizing access-related complications. The purpose of this study was to compare the efficacy and safety of the LifeSite System to a similar but transcutaneous access device, the Tesio-Cath Hemodialysis Catheter. METHODS: The study was conducted in two phases. A multi-center randomized prospective design was utilized for the first phase (Phase 1) where thirty-four patients were enrolled in the Tesio-Cath group and 36 patients into the LifeSite group where 0.2% sodium oxychlorosene was used as an antimicrobial solution for the LifeSite. A nonrandomized, but otherwise identical, second phase of the study followed where a 70% isopropyl alcohol solution was utilized as the antimicrobial solution for 34 additional LifeSite patients (Phase 2). RESULTS: Device function was evaluated in Phase 1 of the trial. Actual blood flow (determined by ultrasound dilution) was greater in the LifeSite versus the Tesio-Cath group (358.7 vs. 331.8 mL/min, P < 0.001 for machine-indicated blood flow of 400 mL/min). Infection comparisons were performed for all three groups encompassing Phase 1 and 2 of the trial; Tesio-Catheter, LifeSite System with oxychlorosene, and LifeSite System with 70% isopropyl alcohol. Device-related infections were defined as systemic bacteremia without another obvious site of origin and exit site infections requiring systemic antibiotics or device removal. This revealed infection rates per 1000 device use days of 1.3 for the LifeSite alcohol group, 3.3 for the Tesio-Cath group, and 3.4 per for the LifeSite oxychlorosene group. There was no statistically significant difference in device related infection rates between the Tesio-Cath and the LifeSite oxychlorosene groups. There were significant differences in infection rate between LifeSite alcohol group and the other two groups (P < 0.05). Device thrombosis was defined by the need for instillation of thrombolytic agents to maintain blood flow>300 mL/min. There was no difference in the need for thrombolytic infusions between the LifeSite oxychlorosene group and the Tesio-Cath group (P = 0.1496); however, the LifeSite alcohol group required significantly fewer thrombolytic infusions than the Tesio-Cath group (P = 0.0295) to maintain adequate blood flow. Device survival at 6 months after stratification by diabetic status and adjusting for age was significantly better in the LifeSite alcohol group (89.9%) than in the LifeSite oxychlorosene group (64.8%, P = 0.0286) and in the Tesio-Cath (69.1%, P = 0.0292) group. CONCLUSIONS: The LifeSite Hemodialysis Access System, when used with 70% isopropyl alcohol as an antimicrobial solution, provides superior performance with a lower infection rate and better device survival than a standard cuffed tunneled hemodialysis catheter.