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When an autologous vein is not available for lower extremity revascularization, prosthetic grafts are often required. However, prosthetic bypass grafts have limited patency for infrageniculate reconstruction. To potentially improve patency, a new geometric modification of the polytetrafluoroethylene (PTFE) graft, Distaflo (Impra, Tempe, AZ), has been developed for lower extremity bypass. We reviewed our early experience with the Distaflo graft in patients who required infrageniculate bypass for lower extremity ischemia when no suitable autologous saphenous vein was available. All patients were maintained on warfarin anticoagulation postoperatively. All grafts were followed at 6- to 12-week intervals with duplex ultrasound evaluation. Patient characteristics, operative procedures, and graft surveillance information were maintained on a computerized registry. Thirty-two patients with limb-threatening ischemia underwent 35 infrageniculate reconstructions with a Distaflo graft between February 26, 1999, and August 24, 2000. Thirty-two of 35 bypasses were performed on extremities that had previously undergone a surgical procedure. Forty-eight previous revascularization procedures were done on these 25 extremities. Thirty grafts were constructed to the tibial outflow sites, whereas the remaining five grafts were placed to the below-knee popliteal artery. One patient died on the second postoperative day secondary to unrelated causes, and only one graft (3%) failed during the same hospitalization. Fifteen of 35 grafts (43%) remained patent 1 to 30 months later. Four patent grafts (6%) were ligated between 2 and 14 months for infectious indications. When considering the 20 failed grafts, 9 patients underwent major amputation, 5 patients remain with chronically ischemic limbs, and 6 patients underwent additional bypass grafts. Twenty-three patients (72%) maintained limb salvage. The Distaflo PTFE graft achieves promising early patency for complex infrageniculate revascularization and may be used as an alternative conduit in patients with critical limb ischemia who do not have an adequate vein for lower extremity revascularization.

Commercially available aortic stent grafts differ in construction and clinical advantage such that creating hybrid endografts by combining components from different manufacturers is sometimes useful. We describe a multicenter experience using hybrid endografts to treat patients with challenging anatomy. Hospital records and office charts were reviewed from four institutions. Hybrid endografts were defined as those with two types of covered stents in continuity to treat an abdominal aortic aneurysm (AAA). Indications for hybrid grafts were defined by type of endoleak and whether an endoleak was expected or unexpected as determined by the preoperative radiographic evaluation. Endpoints include intraoperative endoleaks, late endoleaks, change in aneurysm size, and rupture. Hybrid endografts were used to treat AAA (endovascular aneurysm repair [EVAR]) in 90 patients, representing 7.9% of the total multicenter experience. In 7 patients (7.8%), a hybrid graft construction as a secondary procedure successfully corrected a type 1 endoleak. In the remaining 83 patients (92.2%), hybrid grafts were created at the time of original EVAR to treat expected challenging anatomy or unexpected endoleaks. Hybrid endografts corrected 88 (97.8%) type 1 endoleaks, but 2 patients (2.2%) persisted with a proximal type 1 leak requiring conversion. During follow-up of 1 to 24 months, computed tomography and ultrasound surveillance, available for 73 patients (81.1%), detected one unresolved distal type 1 (1.1%) and seven type 2 (7.8%) endoleaks. Aneurysm size decreased at least 0.5 cm in 23 of 50 patients (46.0%) at 6 months and in 19 of 31 patients (61.3%) at 12 months. Aneurysm size increased at least 0.5 cm in 4 of 50 patients (8.0%) at 6 months and in 1 of 31 patients (3.2%) at 12 months. There were no ruptures. Hybrid endografts have favorable early and intermediate results in the treatment of AAA. Long-term follow-up will be needed to confirm the absence of significant adverse biomaterial interaction and the effect on AAA exclusion. We advocate the use of hybrid endografts as endovascular therapy for patients whose anatomy may be unsuitable for a single endograft type.

Objective: To evaluate the early results of endovascular grafting for high-risk surgical candidates in the treatment of abdominal aortic aneurysms (AAA)., Summary Background Data: Since the approval of endoluminal grafts for treatment of AAA, endovascular repair of AAA (EVAR) has expanded to include patients originally considered too ill for open AAA repair. However, some concern has been expressed regarding technical failure and the durability of endovascular grafts., Methods: The University of Alabama at Birmingham (UAB) Computerized Vascular Registry identified all patients who underwent abdominal aneurysm repair between January 1, 2000, and June 12, 2002. Patients were stratified by type of repair (open AAA vs. EVAR) and were classified as low risk or high risk. Patients with at least one of the following classifications were classified as high risk: age more than 80 years, chronic renal failure (creatinine > 2.0), compromised cardiac function (diminished ventricular function or severe coronary artery disease), poor pulmonary function, reoperative aortic procedure, a "hostile" abdomen, or an emergency operation. Death, systemic complications, and length of stay were tabulated for each group., Results: During this 28-month period, 404 patients underwent AAA repair at UAB. Eighteen patients (4.5%) died within 30 days of their repair or during the same hospitalization. Two hundred seventeen patients (53%) were classified as high risk. Two hundred fifty-nine patients (64%) underwent EVAR repair, and 130 (50%) of these were considered high-risk patients (including four emergency procedures). One hundred forty-five patients (36%) underwent open AAA repair, including 15 emergency operations. All deaths occurred in the high-risk group: 12 (8.3%) died after open AAA repair and 6 (2.3%) died after EVAR repair. Postoperative length of stay was shorter for EVAR repair compared to open AAA., Conclusions: High-risk and low-risk patients can undergo EVAR repair with a lower rate of short-term systemic complications and a shorter length of stay compared to open AAA. Despite concern regarding the durability of EVAR, high-risk patients should be evaluated for EVAR repair before committing to open AAA repair.

Revascularization of extracranial carotid artery stenosis (ECAS) continues to be the subject of spirited academic debate. Conflicting studies in the literature have fostered uncertainty among patients choosing between CEA and CAS. We obtained preference-based utilities from prospective patients being evaluated for ECAS and incorporated them into a decision analytic model. Patients being evaluated for ECAS in an outpatient setting were interviewed prior to their initial visit with a vascular surgeon. Patient preference data were elicited using probability trade-off (PTO) assessment and time trade-off (TTO) method. Decision analysis was performed to compare CEA with CAS. Morbidity and mortality rates were obtained from recent literature reports from the same institution. Our results showed that when patients are informed, they prefer and will more often choose CEA over CAS for revascularization of ECAS. Among patients preferring CAS, they expect no more than a 46% increase in the rate of stroke and/or death. Future clinical studies on true stroke rates for CAS will be required to further refine this analysis.

Background: Only two aortic stent grafts (Ancure-Guidant, Menlo Park, CA, and AneuRx-Medtronic, Sunnyvale, CA) have been FDA-approved for endovascular aortic aneurysm repair (EndoAAA). These grafts differ significantly in construction and clinical advantage, and combining components of these grafts (hybrid graft) is occasionally necessary. The role and outcome of hybrid aortic stent grafts is unknown., Methods: All EndoAAA procedures during an 18-month period (10/99-4/01) were reviewed using the hospital record and a computer registry. Endografts were classified as hybrid if components from more than one type of stent graft were used or standard if constructed from only one stent graft type. Hybrid grafts were further classified as "anticipated" or "unanticpated." Outcomes were compared between hybrid and standard grafts using Fisher's exact test., Results: One hundred forty-five EndoAAA repairs were performed (AneuRx, 67; Ancure, 70; and custom-made, 8) of which 14 (9.6%) were hybrid grafts. The majority of hybrid grafts (11) were constructed by adding AneuRx aortic or iliac cuffs to Ancure grafts. In most cases, the need for a hybrid graft was unanticipated (10) and related to an intraoperative proximal type I endoleak (7). Conversion to open operation was avoided in six patients by constructing hybrid grafts. When anticipated (4), hybrid grafts were constructed to treat complex iliac aneurysms. Outcomes in all categories were similar (P > 0.05) for hybrid vs standard grafts: technical success (93 vs 99%), conversion toopen AAA (7.1 vs 2.3%), vascular complications (7.1 vs 7.6%), systemic complications (21 vs 11%), endoleak (15 vs 14%), and rupture (0 vs 0%)., Conclusions: The short-term safety and effectiveness of hybrid grafts are similar to those of standard grafts. Combining graft components to create hybrid grafts may increase the ability to treat complex iliac aneurysmal disease and may reduce conversions to open AAA repair. Thus, access to multiple graft types may be an important factor in the success and safety of EndoAAA repair.

Background: Carotid angioplasty and stenting is under investigation in clinical trials as an alternative to endarterectomy. Some clinicians have hypothesized that stenting would be applicable for patients at high risk who need carotid revascularization. To further test this hypothesis, we stratified our carotid endarterectomy procedures according to current carotid stent protocols., Methods: We reviewed our computerized registry and the clinical charts of patients who underwent carotid endarterectomy. Each procedure was categorized as high risk or low risk, according to the following six separate high-risk factors: 1, severe cardiac dysfunction; 2, the requirement for combined coronary and carotid vascularization; 3, severe pulmonary dysfunction; 4, contralateral internal carotid artery occlusion; 5, previous ipsilateral carotid endarterectomy; and 6, anatomically limited access for carotid endarterectomy. Rates of stroke at 30 days, cardiac complications, and death were tabulated., Results: Between January 1, 1998, and December 31, 2000, 415 carotid endarterectomies were performed on 389 patients. Ninety-eight procedures (23.6%) were classified as high risk on the basis of the following factors: 1, severe cardiac dysfunction (n = 30); 2, requirement for combined coronary and carotid revascularization (n = 14); 3, severe pulmonary dysfunction (n = 8); 4, contralateral carotid occlusion (n = 31); 5, previous ipsilateral carotid endarterectomy (n = 25); and 6, anatomically limited access (n = 4). Seven patients had ipsilateral postoperative strokes (1.7%), with two additional patients having contralateral hemispheric strokes. One patient died from exacerbation of congestive heart failure 9 days after undergoing a second carotid endarterectomy. The total stroke and death rate was 2.6% for all the patients. Two of the 98 procedures in the high-risk group were complicated with ipsilateral stroke (2.0%) as compared with six of the 317 low-risk procedures (1.9%; P = 1). Six procedures were complicated with cardiac dysfunction after surgery, including myocardial infarction, congestive heart failure, or the new onset of atrial fibrillation. Three cardiac complications occurred in the low-risk group (1%), and three occurred in the high-risk group (3.1%; P =.15)., Conclusion: This series shows that patients at high risk can undergo carotid endarterectomy with stroke rates equivalent to the rates of patients at low risk. The cardiac morbidity rate may be increased in the high-risk group. Carotid stenting is unlikely to offer any improvement in stroke risk as compared with carotid endarterectomy, but stenting may reduce non-stroke morbidity rates associated with some high-risk cases.

Background: Endoscopic saphenous vein harvest has been explored as a minimally invasive alternative to a long continuous leg incision for removal of the greater saphenous vein. The endoscopic technique uses limited incisions (2-4) with extended "skin bridges" and videoscopic equipment for the dissection and removal of the greater saphenous vein. This study was undertaken to evaluate the long-term durability of saphenous vein grafts harvested by an endoscopic technique and used for lower extremity arterial revascularization., Methods: All patients who underwent endoscopic saphenous vein harvesting for lower extremity arterial bypass grafting were prospectively followed for graft patency and risk factors. Grafts were surveyed with serial duplex scans at 3- to 6-month intervals over this 5-year study. Life-table methods were used to assess graft survival. A computerized registry and medical records were reviewed to determine graft patency and patient survival., Results: From September 1994 to August 2000, 164 lower extremity arterial saphenous vein grafts harvested by an endoscopic technique were used for lower extremity arterial bypass grafting in 150 patients. The patient population included 111 males (75%) and 112 smokers (75%), but also included a high-risk cohort of 65 diabetic patients (43%) and 15 patients undergoing dialysis/renal transplant (10%). Twenty-eight patients (19%) died within the study period. With life-table methods, 1-, 3-, and 5-year secondary patency rates were 85% (+/- 3.2%), 74% (+/- 5.7%), and 68% (+/- 11.6%). Of the 30 failed grafts, 7 (4%) failed in the first month related to inadequate runoff (4), cardiac instability (2), and an additional surgical procedure (1). Twenty-three grafts (14%) failed between 1 and 42 months. Twenty-two (16%) of these 134 patent grafts underwent a second procedure to maintain patency (13 as primary-assisted patency and 9 as secondary patency)., Conclusions: Endoscopic saphenous vein harvest for lower extremity arterial reconstruction provides a satisfactory conduit for lower extremity bypass grafting. Although increased manipulation from this limited access technique may incite an injury response in the vein, these vein grafts can maintain an adequate patency for lower extremity bypass grafting.

Blunt abdominal aortic trauma occurs in up to 0.04% of all nonpenetrating traumas. Although uncommon, mortality from this injury ranges from 18% to 37%. Seat belt injury is associated with almost 50% of reported blunt abdominal aortic traumas. The authors present the case of a 21-year-old man, a restrained passenger who was involved in a high-speed motor vehicle accident. In the emergency room, he had obvious evidence of lap-belt injury. His peripheral pulses were normal and there was no pulsatile abdominal mass. Computer tomography (CT) revealed a large amount of free intraperitoneal fluid throughout with signs of mesenteric avulsion and fracture/dislocation of T11-T12. The patient underwent an exploratory laparotomy. Right hemicolectomy and resection of small bowel was performed. CT angiography revealed an aortic transection and surrounding pseudoaneurysm 2 cm above the aortic bifurcation. The patient returned to the operating room for endovascular repair. Via a right femoral cutdown, a 14 mm x 5.5 cm stent-graft was placed across the distal abdominal aorta. Follow-up arteriogram revealed complete obliteration of the pseudoaneurysm without evidence of leak. There were no complications related to the aortic stent-graft in the postoperative period. The patient was discharged in good condition. As this case demonstrates, endovascular repair of traumatic aortic injury is feasible and may represent an improved treatment in certain settings.

Purpose: Telemedicine coupled with digital photography could potentially improve the quality of outpatient wound care and decrease medical cost by allowing home care nurses to electronically transmit images of patients' wounds to treating surgeons. To determine the feasibility of this technology, we compared bedside wound examination by onsite surgeons with viewing digital images of wounds by remote surgeons., Methods: Over 6 weeks, 38 wounds in 24 inpatients were photographed with a Kodak DC50 digital camera (resolution 756 x 504 pixels/in2). Agreements regarding wound description (edema, erythema, cellulitis, necrosis, gangrene, ischemia, and granulation) and wound management (presence of healing problems, need for emergent evaluation, need for antibiotics, and need for hospitalization) were calculated among onsite surgeons and between onsite and remote surgeons. Sensitivity and specificity of remote wound diagnosis compared with bedside examination were calculated. Potential correlates of agreement, level of surgical training, certainty of diagnosis, and wound type were evaluated by multivariate analysis., Results: Agreement between onsite and remote surgeons (66% to 95% for wound description and 64% to 95% for wound management) matched agreement among onsite surgeons (64% to 85% for wound description and 63% to 91% for wound management). Moreover, when onsite agreement was low (i.e., 64% for erythema) agreement between onsite and remote surgeons was similarly low (i.e., 66% for erythema). Sensitivity of remote diagnosis ranged from 78% (gangrene) to 98% (presence of wound healing problem), whereas specificity ranged from 27% (erythema) to 100% (ischemia). Agreement was influenced by wound type (p < 0.01) but not by certainty of diagnosis (p > 0.01) or level of surgical training (p > 0.01)., Conclusions: Wound evaluation on the basis of viewing digital images is comparable with standard wound examination and renders similar diagnoses and treatment in the majority of cases. Digital imaging for remote wound management is feasible and holds significant promise for improving outpatient vascular wound care.

Myocardial infarction after noncardiac surgery in patients with coronary artery disease results from the interplay of patient-specific, anesthetic-specific, and surgery-specific factors. Surgery-specific factors include the stress response to injury, both neurohormonal and hemostatic alterations, and clinically-significant operative parameters such as urgency, duration, blood loss, body core temperature, fluid shifts, and location of surgery. The impact of these factors bears out during the entire perioperative period and influences preoperative risk assessment, cardiac evaluation and intervention, intraoperative strategy, and postoperative management. Overall, the morbidity and mortality of surgery is minimal even in high-risk patients, and the contribution of surgery-specific factors to operative risk is subtle compared with that of patient specific-factors such as severity of coronary disease and other comorbid conditions. Nonetheless, the optimal surgical management of patients with coronary disease requires the collaborative effort of the anesthesiologist, cardiologist, and surgeon.

We hypothesized that the disrupted gastrointestinal transit that occurs during endotoxemia is mediated by nitric oxide (NO) and that the inhibition of NO synthesis will normalize intestinal transit and gastric emptying. To determine the effects of endotoxin and steroids on the activity of gastrointestinal smooth muscle NO synthase, rats underwent placement of an intravenous (iv) line and then were given Escherichia coli lipopolysaccharide (LPS) 10 mg/kg/iv; LPS, 10 mg/kg/iv + dexamethasone, 3 mg/kg/iv; or saline. The activity of nitric oxide synthase in the stomach, small intestine, and colon were determined by measuring the conversion of L-[3H]arginine to L-[3H]citrulline. To determine intestinal transit and gastric emptying, gavage feedings of nonabsorbable liquid markers were given and rats divided into eight groups: 0.9% NaCl, 1 ml/hr x 5 hr (control); LPS, 10 mg/kg/iv; LPS + N-omega-nitro-L-arginine methyl ester (L-NAME), 10 mg/kg/hr x 5 hr; LPS + N-omega-nitro-D-arginine methyl ester (D-NAME), 10 mg/kg/hr x 5 hr; LPS + L-arginine, 100 mg/kg/hr x 5 hr; LPS + L+NAME + L-arginine; LPS + N-omega-nitro-L-arginine (L-NNA) 10 mg/kg/hr; or LPS + L-NNA + L-arginine. LPS increased the enzymatic activity of both the constitutive and the inducible forms of NO synthase in the small intestine and fundus of the stomach. The acceleration of intestinal transit produced by endotoxemia was reversed with both L-NAME and L-NNA but not with D-NAME. Endotoxemia slowed gastric emptying but this effect was not reversed with either L-NAME or L-NNA. We conclude that NO plays a major role in mediating the rapid intestinal transit during endotoxemia.

Prostanoid activity was correlated with the hemodynamic effects of protamine sulfate reversal of heparin in 24 dogs undergoing three different pretreatment regimens: Group I (n = 8) received saline, Group II (n = 8) received the thromboxane synthetase inhibitor U63,557A (30 mg/kg), and Group III (n = 8) received indomethacin (10 mg/kg). Pretreatment substances were administered as 5-min intravenous infusions 20 min before anticoagulation with intravenous heparin (150 IU/kg). Protamine sulfate (1.5 mg/kg) was subsequently given as a 10-sec intravenous infusion 30 min after heparin had been administered. Hemodynamic data, as well as prostacyclin (PGI2) and thromboxane (TxA2) activity in aortic, venous, and pulmonary artery blood samples, were assessed over a 30-min time period following protamine administration. Group III indomethacin pretreatment provided the most protection from declines in blood pressure, heart rate, cardiac output, venous oxygen saturation, oxygen consumption, and elevations in pulmonary pressures and was accompanied with actual declines in PGI2. Group II U63,557A pretreatment was associated with the most severe hemodynamic changes and the greatest increase in PGI2 (+576%). Elevated PGI2 correlated with hypotension at 1 and 3 min (P less than 0.01), as well as pulmonary artery pressure declines at all times following protamine reversal. TxA2 changes did not correlate with hemodynamic changes. Protamine's adverse hemodynamic responses were attenuated with cyclooxygenase blockade by indomethacin, but were worsened with selective TxA2 blockade with U63,557A. Excess arachadonic acid precursors in the latter setting may increase PGI2 production. This study, for the first time, raises the possibility that PGI2 contributes to the adverse effects accompanying protamine reversal of heparin anticoagulation.