Upper extremity trauma: current trends in management.

Upper extremity trauma can be penetrating or blunt in etiology. The close proximity of vein, artery and nerve makes for a complicated presentation and potentially complicated reconstruction. Orthopedic and neurologic injuries can cause the more long term disability of these patients, but vascular injuries are initially more life threatening. Control of vascular injuries can be particularly difficult due to anatomic issues in the upper extremities. The intervention carried significant morbidity until evolution to endovascular approaches occurred. By reconstructing the injury from a more ''remote'' access site, less concomitant injury to the extremity can be encountered. However, although control of vascular injuries may result in greater survival rates with less morbidity from the procedure, long term outcome remains dependent upon concomitant injuries. This review will encompass both vascular and neurologic injuries secondary to trauma to the upper extremity and outline some of the trends in management.

Brave new world: the role for endovascular aneurysm repair in contemporary vascular surgery.

Endovascular abdominal aortic aneurysm repair (EVAR) poses certain challenges to the vascular surgeon. Based upon our 6-year experience, we have highlighted important aspects of patient selection. EVAR can be performed in patients with significant co-morbidities, but technical success may be limited by anatomic criteria. Short to mid-term outcomes report low mortality and morbidity from EVAR. Acute and delayed conversion, rupture, endoleak, limb occlusion, and migration are complications occurring in EVAR; their frequency, presentation and management are described. EVAR has up to 90% success rate at several years follow-up including the use of secondary procedures. Secondary procedures are not infrequent after EVAR; thus close follow-up is of the utmost importance. We predict that EVAR will continue to be a valuable tool in the future.

Prevention and management of ureteral injuries during aortic surgery.

Ureteral injury during aortic surgery may lead to life-threatening consequences. Unlike gynecologic or abdominal surgical procedures in which ureteral injuries more commonly occur, this type of iatrogenic injury may be particularly hazardous because of the presence of prosthetic graft material. Ureteral obstruction by extrinsic compression, from an anteriorly placed graft limb or retroperitoneal fibrosis, is the most commonly reported type of ureteral complication. In most vascular surgical series, direct ureteral injury occurs in less than 1% of cases, and ureteral obstruction occurs from 2% to 14% of aortoiliac reconstructions. Prevention of ureteral injury begins with an intimate knowledge of the anatomy of the ureter along its entire course from the abdomen to the pelvis, and a realization of possible anomalies. Recognition of an injury is the next key to a successful outcome. Intraoperative recognition of an injury may allow immediate repair with a high rate of success. There are many options for the management of ureteral injuries depending on the nature of the injury, the time of diagnosis, and the level of the ureter at which the injury has occurred. The authors review the anatomy and most common causes of ureteral injury during aortic surgery and provide a guide to appropriate surgical management of these injuries.

Influence of NASCET/ACAS trial eligibility on outcome after carotid endarterectomy.

PURPOSE: Proponents of carotid angioplasty and stenting suggest that "high risk" patients, defined as patients excluded from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and Asymptomatic Carotid Atherosclerosis Study (ACAS), may have a significantly higher risk of stroke with carotid endarterectomy (CEA). However, this selected patient cohort has been poorly studied. METHODS: A retrospective review of patients who underwent CEA during a 2-year period at a tertiary referral institution was performed. Each patient was evaluated and categorized, according to the exclusion criteria, by NASCET and ACAS standards. Statistical analysis using chi(2) and Fisher exact tests was performed. RESULTS: There were 366 CEAs performed on 348 patients, including 32 (8.7%) for recurrent stenosis. A subgroup of 169 (46.2%) patients were trial ineligible. Focal ipsilateral symptoms were present in 148 (40.4%) of the patients. There were 9 (2.5%) strokes and 1 (0.3%) death, secondary to a major stroke, for an overall stroke and death rate of 2.5%. Trial-eligible patients had a stroke/death rate of 1.5% (3/197) while trial-ineligible patients had a 3.6% (6/169) stroke/death rate (P = .17). CONCLUSION: Patients who were considered high risk for CEA as defined by trial ineligibility were common, comprising approximately half of our patients. Although trial-ineligible patients had a nonsignificant trend toward higher neurologic morbidity when compared with the eligible group, the risks were still comparable with NASCET/ACAS results. CEA was a safe procedure even in this "high risk" group. As such, ineligibility for a randomized carotid intervention trial should not be employed as a "de novo" indication for carotid stenting.

Development of oral heparin therapy for prophylaxis and treatment of deep venous thrombosis.

OBJECTIVE: To review the current research and published literature regarding the development of oral heparin therapy for the prophylaxis and treatment of deep venous thrombosis. BACKGROUND: Currently, the accepted practice of prophylaxis and/or treatment of acute deep venous thrombosis (DVT) is intravenous or subcutaneous (SQ) heparin followed by oral warfarin or SC low molecular weight heparin (LMWH) therapy followed by warfarin. Both of which are less than ideal. More recently, advances have been made towards an effective oral heparin preparation that would resolve many of the drawbacks to the current therapies. METHODS: A review of the current and relevant English literature identified via a search of the Medline database from January 1990 to present. RESULTS: Initial oral heparin therapy for DVT was unsuccessful due to presumed inadequate intestinal absorption as a result of heparin's molecular and structural characteristics. The development of oral heparin therapy, based on combining heparin with the carrier molecule Sodium N-(8[2-hydroxybenzoyl]amino) caprylate (SNAC) to enhance its intestinal absorption and bioavailability for the prophylaxis and treatment of DVT has been demonstrated to be effective in animal models. More recent efforts have been aimed at human trials. CONCLUSION: Recent advances in prophylaxis and treatment of DVT have stimulated great interest among researchers to develop an effective, convenient, and well tolerated oral therapy. An effective oral heparin therapy may represent an ideal method of prophylaxis and treatment of DVT.

External transabdominal manipulation of vessels: a useful adjunct with endovascular abdominal aortic aneurysm repair.

During endovascular abdominal aortic aneurysm repair, a severely angulated aortic neck or tortuous iliac arteries can make delivery of endografts difficult. We describe a simple adjunct in which transabdominal manipulation of vessels is used, which can greatly facilitate delivery of these devices in patients with challenging anatomy.

Comparison of open transabdominal AAA repair with endovascular AAA repair in reduction of postoperative stress response.

Operative intervention causes a necessary biologic response known as the hypermetabolic stress response. Less invasive operative procedures may cause fewer metabolic and endocrine derangements. To evaluate the metabolic and endocrine differences between endovascular and transperitoneal abdominal aortic aneurysm (AAA) repair, 10 patients underwent standard open repair (open group) and 10 patients underwent endovascular repair of AAA (endovascular group) with a modular bifurcated endograft. Blood samples were obtained prior to general anesthesia (baseline) and every 6 hr for a 24-hr period. Assays for hormones related to the postoperative stress response as well as retinol-binding protein were performed. Peak hormonal values are presented in relation to the baseline. Demographic analysis of the two groups showed that there were no significant differences in age or ASA classification. The open group had a 9.6-fold increase in epinephrine release, which was significantly higher than the 1.6-fold increase in the endovascular group (p < 0.05). Elevations in cortisol were also significantly higher in the open group. Early postoperative nutritional derangements, as reflected by the levels of retinol-binding protein, were far less in the endovascular group than in the open group. Endovascular AAA repair appears to be associated with a marked reduction in the hypermetabolic stress response and nutritional deterioration, compared to traditional open repair. This reduction in physiologic stress may have salutary effects on the incidence of postoperative medical morbidity.

Orally administered unfractionated heparin with carrier agent is therapeutic for deep venous thrombosis.

BACKGROUND: Orally administered heparin (OHEP) is unreliable because of poor absorption. Sodium N-(8[2-hydroxybenzoyl]amino) caprylate (SNAC) is an amido acid that facilitates the gastrointestinal absorption of heparin. We evaluated the effectiveness of OHEP combined with SNAC (OHEP/SNAC) in the treatment of deep-vein thrombosis (DVT). METHODS AND RESULTS: An internal jugular DVT was produced in 54 male Sprague-Dawley rats. Animals were assigned to 6 different groups for 7 days of treatment: untreated control, subcutaneous heparin (SC HEP) (300 U/kg SC TID), SNAC only (300 mg/kg PO TID), OHEP only (30 mg/kg PO TID), low-molecular-weight heparin (LMWH) (enoxaparin 5 mg/kg SC QD), and OHEP/SNAC (30 mg/kg:300 mg/kg PO TID). The activated partial thromboplastin time (aPTT) and anti-factor X (anti-Xa) levels were measured. The incidence of residual DVT after 1 week of treatment was 100% (9 of 9) in the control group versus 10% (1 of 10) in the OHEP/SNAC and 10% (1 of 10) in the LMWH groups (P<0.001). There was also a significant reduction in clot weights between these groups. Compared with controls, there were no significant differences in the residual DVT in the SNAC-only (6 of 6), OHEP-only (9 of 9), or SC HEP (8 of 10) groups. Combination OHEP/SNAC was as effective in the resolution of the clot and reducing clot weight as LMWH. The aPTT levels in the OHEP/SNAC group peaked at 30 minutes and were significantly higher than in all other groups (P<0.01). Anti-Xa levels were elevated at 15 minutes after dosing in the OHEP/SNAC group and remained significantly elevated at 4 hours (P<0.001). CONCLUSIONS: OHEP combined with a novel carrier agent (SNAC) successfully treated DVT in this rat model.

Endovascular treatment of multiple visceral artery paradoxical emboli with mechanical and pharmacological thrombolysis.

PURPOSE: To report a case of paradoxical emboli to multiple visceral vessels treated with both mechanical (AngioJet device) and pharmacological (urokinase) thrombolysis. METHODS AND RESULTS: A 72-year-old man presented with a 48-hour history of symptomatic right renal ischemia, which was treated with heparinization. Five days later, an abrupt creatinine elevation prompted arteriography, which demonstrated thromboembolism of the superior mesenteric artery (SMA) and both renal arteries. The AngioJet aspiration device was employed to successfully remove the clot from the SMA; urokinase infusion restored flow to the left kidney. At the 16-month follow-up evaluation, the patient was normotensive without medication and had a stable creatinine (1.4 mg/dL). CONCLUSIONS: Because of its speed and minimal morbidity, the AngioJet device may be an attractive alternative to surgical embolectomy or pharmacological thrombolysis in highly selected cases of acute visceral artery thromboembolism.

Treatment of experimentally induced caval thrombosis with oral low molecular weight heparin and delivery agent in a porcine model of deep venous thrombosis.

OBJECTIVE: This experiment evaluated enterally administered low molecular weight heparin (LMWH) combined with sodium N-[10-(2-hydroxybenzoyl)amino] decanoate (SNAD) for the treatment of induced venous thrombosis. SUMMARY BACKGROUND DATA: SNAD is a delivery agent that potentiates the gastrointestinal absorption of LMWH. METHODS: Forty female pigs were equally assigned to four groups: control (saline); enteral LMWH, 2,000 IU/kg; enteral SNAD, 50 mg/kg; and enteral LMWH, 2,000 IU/kg and SNAD, 50 mg/kg. Under fluoroscopic guidance, the infrarenal vena cava was occluded with a balloon catheter. Two milliliters of ethanol was injected into the distal vena cava. The inflated balloon catheter remained in situ for 5 days, at which time animals angiographically exhibiting thrombus were randomly assigned to the four groups. Study medications were dosed at 12-hour intervals by means of a gastrostomy tube placed previously. After 7 days of treatment, thrombus was extracted. A separate group of 10 animals was used to measure plasma antifactor Xa levels for 6 hours after enteral dosing of LMWH/SNAD. RESULTS: The amount of residual thrombus after treatment with enteral LMWH/SNAD was significantly decreased. Antifactor Xa levels were significantly elevated in the LMWH/SNAD group versus baseline. CONCLUSION: The combination of enterally administered LMWH and SNAD given for 7 days appeared to decrease caval thrombosis in this model of deep vein thrombosis. Enteral LMWH/SNAD effected an increase in plasma levels of antifactor Xa.

Hospital cost of endovascular versus open repair of abdominal aortic aneurysms: a multicenter study.

BACKGROUND: Technology-driven innovation in medicine is frequently associated with higher costs than conventional therapy. A significantly higher cost for endovascular ($21,250, n = 190) versus open abdominal aortic aneurysm (AAA) repair ($12,342, n = 60) was suggested by a direct cost analysis of patients in a multicenter trial. Estimated inpatient costs (not charges) incurred nationwide by hospitals for endovascular and open repair of AAA were studied to validate these observed trends. METHODS: A retrospective analysis of 131 patients undergoing endovascular AAA repair was compared with 49 patients undergoing open repair as part of a Food and Drug Administration phase II prospective multicenter clinical investigation (AneuRx-Medtronic). A model to estimate costs was constructed using important clinical descriptors of these patients. These clinical characteristics where then matched with those from 22, 460 patients undergoing AAA repair obtained from a large national database (Medicare Provider Analysis and Review). Estimated hospital cost was then assigned to each study patient according to the national average of the total hospital costs for the respective matched patients in Medicare Provider Analysis and Review. RESULTS: Total inpatient hospital costs of endovascular repair were significantly higher than that of open repair ($19,985 +/- 7396 versus $12,546 +/- 5944, respectively, P =.0001). Endograft device cost ($10,400) accounted for 52% of the total cost of endovascular repair. The 1999 mean blended Medicare reimbursement for AAA repair was $18,989. CONCLUSION: In this early development stage, hospital cost for endovascular AAA repair is significantly greater than open repair when device cost greatly exceeds $5000. Although incremental reductions in cost of endovascular repair may be anticipated if use of diagnostic studies, operating time, and length of stay decrease, device cost has the single greatest impact on the expense of endovascular AAA repair. At current device pricing, mean blended Medicare reimbursement does not cover the cost of endovascular AAA repair.

Minimally invasive vascular techniques.

The recent and continuing developments in radiotherapy, gene therapy, and the technologies of imaging, materials, and devices, as well as the techniques for their implementation, have expanded the options available for the treatment of peripheral vascular disease. Though long-term data are still lacking, percutaneous transluminal angioplasty (PTA) has developed into a treatment modality in its own right and continues to be an adjuvant treatment to traditional surgical revascularization. Numerous stents and grafts are currently available for the treatment of arterial lesions and aneurysms, while the testing of many more continues. In addition to these new devices, developments in gene therapy and brachytherapy have brought several new minimally invasive options to the treatment of peripheral vascular disease.

Complications associated with percutaneous closure devices.

BACKGROUND: In an effort to reduce time to hemostasis after angiography, several closure devices have been marketed. We report some of their complications. METHODS: A retrospective review was conducted. RESULTS: Over an 8-month study period, 2,181 diagnostic and interventional procedures were performed. Closure devices were used in 408 (19%) of these patients. The Angio-Seal closure device is composed of a collagen sponge and an absorbable polymer anchor that compresses the hole in the arteriotomy. The ProstarXL sealing device consists of a rotating barrel that deploys 4 needles through the arteriotomy, and then individual knots are extracorporeally tied. The Duett device consists of a balloon occluding catheter and injectable collagen and thrombin. Ten of the patients developed a complication from the closure device (2.5%). Four of these were subcutaneous abscesses. Two of these patients had expanding pseudaneurysms, 2 had lower extremity ischemia, and 1 patient had an acute bleed. These complications were all managed surgically. Another patient developed a retroperitoneal bleed that was managed nonoperatively. CONCLUSIONS: As the use of these devices increase, these complications will become more common.

Oral low-molecular weight heparin and delivery agent prevents jugular venous thrombosis in the rat.

PURPOSE: Sodium N-[10-(2-hydroxybenzoyl)amino]decanoate (SNAD) is a novel carrier that allows the gastrointestinal absorption of low-molecular weight heparin (LMWH). The purpose of this experiment was to evaluate oral LMWH with SNAD for the prevention of deep venous thrombosis. METHODS: Sixty Sprague-Dawley rats were equally assigned to five experimental groups: group 1 (control), oral saline solution; group 2, oral LMWH (15 mg/kg); group 3, oral SNAD (300 mg/kg); group 4, subcutaneous LMWH (5 mg/kg); and group 5, oral LMWH (15 mg/kg) and SNAD (300 mg/kg). After treatment, the jugular vein was isolated, occluded, and bathed in an ethanol and formalin solution for 2 minutes. Two hours later, the vessel was examined for patency, presence of thrombus, and thrombus weight. Serum measurement of anti-factor Xa activity was performed in a separate set of 30 rats, which were placed into the following four groups: group A, LMWH (5 mg/kg); group B, oral LMWH (15 mg/kg) and SNAD (300 mg/kg); group C, oral LMWH (15 mg/kg); and group D, SNAD (300 mg/kg). RESULTS: The animals that underwent oral LMWH/SNAD therapy had a statistically significant decrease in visible thrombi. The thrombus weight of the oral LMWH/SNAD group was significantly less than the weights of all other groups, except the subcutaneous LMWH group. Anti-factor Xa levels were significantly elevated in the LMWH/SNAD group. There was no statistically significant difference between the data for the oral LMWH/SNAD group and the subcutaneous LMWH group. CONCLUSION: The combination of oral LMWH and SNAD prevented deep venous thrombosis. The oral LMWH and SNAD therapy effected an increase in levels of anti-factor Xa.

Carotid endarterectomy in patients with significant renal dysfunction.

PURPOSE: Recent reports suggest that carotid endarterectomy (CEA) should not be performed in patients with end-stage renal disease (ESRD) because of an unacceptable rate of perioperative stroke and other morbidity. Because these conclusions were based on a small number of patients, we reviewed the perioperative and long-term outcome of patients with ESRD and chronic renal insufficiency (CRI) who underwent CEA at our institution. METHODS: The 1081 patients who had a CEA between 1990 and 1997 were cross-referenced with those patients in whom renal insufficiency had been diagnosed. These charts were reviewed for patient demographics and perioperative and long-term outcome. Patients undergoing CEA during a 1-year period (1993) served as controls. RESULTS: Fifty-one CEAs were performed in 44 patients with CRI (32 in 27 patients) and ESRD (19 in 17 patients). In the CRI+ESRD group, 66.7% were symptomatic, and 70.7% of the control group were symptomatic. Six operations (11.8%) in the CRI+ESRD group were redo endarterectomies. There were no perioperative strokes in the CRI+ESRD group, but one patient died 29 days postoperatively because of a myocardial infarction, for a combined stroke-mortality rate of 2.0%. The control group had a 2.6% combined stroke-mortality rate. Long-term survival analysis revealed a 4-year survival rate of 12% for patients with ESRD and 54% for patients with CRI, compared with 72% for controls (P <.05). CONCLUSION: CEA can be performed safely in patients with ESRD or CRI, with perioperative stroke and death rates equivalent to that of patients without renal dysfunction. However, the benefit of long-term stroke prevention in the asymptomatic patient with ESRD is in question because of the high 4-year mortality rate of this patient population.

Endovascular repair of abdominal aortic aneurysms.

Endovascular treatment of abdominal aortic aneurysms (AAAs) is an exciting new minimally invasive treatment option for patients with this disease. Ochsner Clinic has been the only institution in the Gulf South participating in FDA clinical trials of these investigational devices. Early results with endovascular AAA repair demonstrate a trend towards lower mortality and morbidity when compared with traditional open surgery. Length of stay has been reduced by two-thirds with a marked reduction in postoperative pain and at-home convalescence. If the long-term data on efficacy and durability of these devices are good, most AAAs in the future will be treated with this minimally invasive technique.

Orally administered heparin for preventing deep venous thrombosis.

BACKGROUND: Sodium N-(8-[2-hydroxybenzoyl] amino) caprylate (SNAC) is an acetylated amino acid molecule that facilitates the gastrointestinal absorption of heparin. This study was undertaken to evaluate the efficacy of orally administered combination SNAC:heparin in preventing deep venous thrombosis in a standard rat model. METHODS: Forty-four adult male Sprague-Dawley rats were randomly divided into five groups: group I control, group II SNAC, group III oral heparin, group IV combination SNAC:heparin, and group V intravenous heparin. Thirty minutes after drug administration, the internal jugular vein was bathed in a sclerosant mixture for 2 minutes and reexplored at 120 minutes. Activated partial thromboplastin times (aPTT) were measured in 30 rats equally divided into three groups: group I SNAC, group II oral heparin, and group III combination SNAC:heparin. Forty-five minutes posttreatment, blood was obtained for aPTT levels. RESULTS: The incidence of deep venous thrombosis in the control group was 89% (8 of 9) versus 25% (2 of 8) in the combination SNAC:heparin group (p < 0.01). There was also a significant reduction in clot weight among groups. Combination SNAC:heparin significantly increased aPTT levels compared with SNAC or oral heparin alone. CONCLUSION: In a rat model of venous thrombosis, combination of orally administered heparin:SNAC elevated aPTT levels and significantly reduced the formation of deep venous thrombosis.

Effect of cilostazol on walking distances in patients with intermittent claudication caused by peripheral vascular disease.

PURPOSE: This study evaluated the effects of cilostazol on walking distances in patients with intermittent claudication (IC) caused by peripheral arterial occlusive disease. METHODS: The study was a multicenter, randomized, double-blind, placebo-controlled trial. Two hundred thirty-nine patients with IC were randomly assigned to receive cilostazol (100 mg b.i.d.) or a placebo for 16 weeks. All patients underwent serial, variable-grade, constant-speed treadmill testing. Absolute claudication distance (ACD), assessed at the end of the 12-hour dosing interval (trough), was the primary end point. Secondary end points included ACD assessed 3 to 4 hours after dosing (peak) and initial claudication distances (trough and peak). Functional status measures, including the Medical Outcomes Scale (SF-36) and Walking Impairment Questionnaire, were used to assess subjective changes over the 16-week treatment period. Ankle-brachial indexes were calculated from Doppler-measured systolic pressures at every visit with treadmill testing. RESULTS: Patients treated with cilostazol demonstrated significant improvements over the placebo patients in ACD at all three time points tested after baseline (weeks 8, 12, and 16). Peak treadmill testing at weeks 8 and 12 also showed significant improvement in walking distances for cilostazol-treated patients over placebo-treated patients. At week 16, patients in the cilostazol group had a 96.4-meter (47%) increase in ACD compared with 31.4 meters (12.9%) for the placebo group (p < 0.001). In the SF-36, significant improvement was observed in the physical component subscale and the composite physical component score. In the Walking Impairment Questionnaire, improvements were significant in patient reports of walking speed and specific measures of walking difficulty. Ankle-brachial indexes improved in the cilostazol group (0.64 +/- 0.02 to 0.70 +/- 0.02) compared with the placebo group (0.68 +/- 0.02 to 0.69 +/- 0.02) (p < 0.0125). The most frequent adverse events were headache, abnormal stools (e.g. loose stools), diarrhea, and dizziness. CONCLUSIONS: Cilostazol significantly increased ACD at all measured time points and initial claudication distances at most time points. This agent may represent a new treatment option for patients with intermittent claudication.

Management of severe proximal vascular and neural injury of the upper extremity.

PURPOSE: Early amputation has been suggested to be the optimal treatment for severe combined vascular and neural injuries of the proximal upper extremity. This retrospective study was done to evaluate the long-term clinical outcome of our policy of limb salvage by revascularization and delayed treatment of neural injuries. METHODS: Forty-six patients with neural and vascular trauma to the upper extremity were treated at our institution. All of these patients had aggressive treatment directed at limb salvage with restoration of vascular supply and nerve function. Long-term vascular and neurologic outcomes were recorded. Neurologic deficits were validated by the American Medical Association's standardized disability impairment scale (0% to 100%). RESULTS: The rate of preoperative disability was 83%, which improved to 52% (p < 0.01) after treatment (mean follow-up, 43 months). Overall, 87% showed improvement. CONCLUSION: These results suggest that early amputation should not be performed unless there is massive tissue loss or an attempt at limb salvage might endanger life. Final outcomes cannot be predicted on the basis of initial clinical presentation. As a group, the majority of these patients improved with aggressive intervention.

Abdominal and thoracoabdominal aortic aneurysm.

Most abdominal aortic aneurysms (AAA) and thoracoabdominal aortic aneurysms (TAAA) are asymptomatic and are found on physical exam or incidentally during radiological studies for other indications. These aneurysms are repaired primarily because their risk of rupture increases geometrically as the size exceeds 5 cm. The potential morbidity of intraoperative visceral and spinal ischemia involved with TAAA repair may be reduced with various adjunctive maneuvers.