A reappraisal of a modified through-knee amputation in patients with peripheral vascular disease.

BACKGROUND: Through-knee amputation provides a longer lever arm and improved muscle control of the limb compared with above-knee amputation. Through-knee amputation also allows use of a total end-bearing prosthesis, which avoids the ischial pressure and suspension belts required of the above-knee amputation prosthesis. Several reports in the European literature tout the superiority of the through-knee amputation over the above-knee amputation in the patient with vascular disease. Through-knee amputation has received little attention in the United States, however, owing to the belief that the long flaps necessary to close a standard through-knee amputation are associated with an unacceptable rate of wound problems and offer no functional ambulatory advantage to above-knee amputation. We reviewed our experience with a modified technique of through-knee amputation in a group of patients with severe lower extremity ischemia who were not candidates for below-knee amputation to determine the incidence of wound complications and their functional outcome. METHODS: Since 1996, 12 patients with severe lower extremity arterial insufficiency have undergone through-knee amputation utilizing a technique designed to limit flap length and facilitate the fit of a suction prosthesis. Two patients died of myocardial infarction in the immediate postoperative period and were excluded from the study. In the remaining 10 patients (1 man, 9 women; mean age 63 years (range 40 to 86), the below-knee amputation level was precluded because of gangrene or nonhealing wounds of the mid leg in 5 patients, failure of a previous below-knee amputation attempt in 4 patients, and severe ischemia that would compromise below-knee amputation healing in 1 patient. Nine patients had at least one failed vascular reconstruction procedure. RESULTS: Mean follow-up is 25 months (range 6 to 41). Six (60%) patients had primary healing of their amputations. Two (20%) patients had delayed healing (6 weeks and 8 weeks). Two (20%) patients developed wound infections, which required amputation revision to the above-knee level. Seven (70%) patients were fitted with a suction socket prosthesis and are fully ambulatory. One patient healed but has not ambulated because of ischemia and subsequent ulceration of the contralateral limb. CONCLUSIONS: These data show that through-knee amputation is associated with an acceptable primary healing rate (80%) and satisfactory functional outcomes (70% ambulation) in a high-risk vascular population. The functional advantages of through-knee amputation over above-knee amputation make it the preferred alternative for patients with vascular disease.

Concomitant renal revascularization with aortic surgery: are the risks of combined procedures justified?

Indications for concomitant renal revascularization during aortic surgery are not well established. Higher mortality and poorer results are often cited. To examine this, all combined aortic and renal revascularization procedures from August 1992 until May 1998 were reviewed. Of 2003 major arterial reconstructions performed on the Vascular Teaching Service, 45 patients (2%) underwent renal revascularization. Of these 31 patients (69%) had combined aortic and renal procedures. Aortic pathology in these 31 patients (54% male, 94% white, median age 64 years) included arterial occlusive disease (n = 21; 47%), abdominal aortic aneurysm (n = 6; 13%), and thoracoabdominal aortic aneurysm (n = 4; 9%). In all 31 cases the patient presented because of the aortic pathology. Indications for concomitant renal revascularization included renovascular hypertension (n = 21; 68%) and preservation of renal function (n = 10; 32%). Renal revascularization procedures included transaortic endarterectomy (n = 23; 74%), renal bypass (n = 7; 23%), and both bypass and endarterectomy (n = 1; 3%). Seven (22%) complications and two (6%) deaths (both patients operated on for renal salvage) occurred perioperatively. Complications included wound infection (n = 2; 6%), postoperative bleeding (n = 1; 3%), respiratory failure (n = 1; 3%), deep venous thrombosis (n = 1; 3%), cerebrovascular accident (n = 1; 3%), and pseudomembranous enterocolitis (n = 1; 3%). All patients either were cured of their hypertension (n = 5; 24%) or were improved (n = 16; 76%) at 3 months. No patient to date operated on for renal salvage progressed to chronic hemodialysis, but mortality was higher after renal revascularization for renal salvage versus hypertension (20% vs. 0; P = 0.034). There was no significant difference in mortality between the combined aortic/renal procedures versus aortic procedures alone. Despite adding complexity, renal revascularization in patients undergoing aortic surgery appears relatively safe and effective. These data favor an aggressive approach toward renal revascularization in selected patients needing aortic surgery.

Isolated arteriovenous dialysis access graft segment infection: the results of segmental bypass and partial graft excision.

Arteriovenous (AV) access graft infection results in disruption of dialysis and usually necessitates graft removal when the entire graft is involved. The management of an isolated infected segment of an otherwise noninfected AV access graft, however, remains controversial. To evaluate the utility of segmental bypass and partial graft excision for the treatment of an isolated infected AV access graft segment, 17 consecutive cases in 12 patients (7 females/5 males; 14 arm grafts/3 leg grafts; median age = 69 years) were analyzed on a vascular teaching service that performed 1244 total access procedures from January 1995 through February 1999. Infections presented as a draining sinus or a sinus with hemorrhage emanating from an area over the graft. At operation, the infected sinus was covered by a transparent occlusive dressing and the graft was explored through clean incisions proximal and distal to the infected segment. If the graft was incorporated and free of infection, a piece of expanded polytetrafluoroethylene (ePTFE) was anastomosed proximally end-to-end and tunneled through noninfected tissues around the infected sinus. After the distal anastomosis was performed, the skin incisions were closed and covered with occlusive dressings. The infected graft segment was then removed through the infected sinus wound. The technique of segmental bypass and partial graft excision results in predictable eradication of infection, graft salvage, and maintenance of uninterrupted dialysis in patients presenting with an isolated AV dialysis access infection.

Ultrasound-guided thrombin injection of iatrogenic femoral pseudoaneurysms: a prospective analysis.

An adverse consequence of the use of the femoral artery for the endovascular evaluation and treatment of arterial disease is the increased incidence of iatrogenic femoral pseudoaneurysms. Although surgical repair has traditionally been used to treat such aneurysms, less invasive modalities have emerged. The purpose of this study is to prospectively evaluate ultrasound-guided thrombin injection (UGTI) for the treatment of iatrogenic femoral pseudoaneurysms. A treatment protocol was approved and 30 stable patients (21 female; age range 43-85 years; mean 67 years) were prospectively enrolled from December 1997 through June 1999 to undergo UGTI on 30 iatrogenic femoral pseudoaneurysms. Pseudoaneurysms occurred after cardiac intervention (n = 22, 73%), peripheral intervention (n = 7, 23%), and after a femoral line placement (n = 1, 3%). They ranged in size from one to 5 cm with a time interval from intervention until UGTI of one to 132 days (median 3 days). Eleven patients (37%) were systematically anticoagulated at the time of UGTI. All pseudoaneurysms were treated using sterile technique and local anesthesia with ultrasound-guided injection via a 20-gauge spinal needle of 0.1 to 2 cm3 (median 0.6 cm3) of 1000 units/cm3 topical thrombin solution administered by one of six physicians. A period of bedrest for 4 to 6 hours after injection was followed by repeat groin duplex scan at 24 hours and a clinical follow-up at 30 days. There were no procedural deaths or nonvascular complications. Twenty-seven (90%) UGTIs resulted in successful pseudoaneurysm ablation with no recurrences at 24 hours or 30 days. Two (7%) UGTIs failed and one (3%) femoral artery embolic complication occurred; all were successfully treated with surgery. Success appeared to be independent of anticoagulation status, pseudoaneurysm age, size, or operator experience. We conclude that UGTI is a safe, easy, well-tolerated and effective noninvasive method for treatment of iatrogenic femoral pseudoaneurysms and should be considered in all stable patients before operative repair.

The impact of a community-wide vascular access program on the management of graft thromboses in a dialysis population of 495 patients.

BACKGROUND: The unpredictability of prosthetic vascular access thrombosis precludes the scheduling of elective graft thrombectomy. This results in inconsistent dialysis for patients, as well as logistical challenges for dialysis clinics and surgeons, and increased cost. In an effort to solve this problem a community-wide, prospective vascular access program (VAP) was established. This study evaluates the impact of the VAP by comparing the operative procedures and outcomes of vascular access surgery performed in the community before and after establishment of the program. METHODS: All 17 surgeons who perform vascular access, representing five independent practice groups in Greenville, South Carolina, formed a VAP in November 1996. Dialysis patients were pooled, and all graft thrombectomies were managed on a rotational basis by a surgeon assigned daily to a specifically designated access thrombectomy operating room. The hospital records of all patients undergoing vascular access procedures from November 1, 1995, through October 31, 1996 (pre-VAP), and November 1, 1996, through October 31, 1997 (post-VAP), were reviewed. RESULTS: Comparison of the pre-VAP and post-VAP groups showed no significant difference in the number of patients undergoing vascular access procedures (391 versus 378), number of vascular access procedures performed (1034 versus 1,048), or average number of vascular access procedures performed per patient (2.64 versus 2.79). There was no statistical difference in the number of thrombectomies and revisions (786 versus 765; P = 0.114) or thrombectomies alone (248 versus 283; P = 0.114) in the pre-VAP and post-VAP groups. There was a significant increase in the number of procedures performed on an outpatient basis in the post-VAP group (757; 73%) compared with the pre-VAP group (575; 56%); P <0.001. There was also a significant difference in the percentage of cases performed after 6:00 PM in the pre-VAP group (262; 25%) compared with the post-VAP group (48; 4.5%; P = 0.001). CONCLUSIONS: Dialysis graft thrombosis, occurring in 75% of our patients annually, represents a substantial logistical dilemma necessitating the incorporation of 1,000 additional operations into a busy elective surgery schedule. An organized VAP reduces inpatient hospitalization, minimizes expensive after hours surgery, and enhances patient and physician convenience while providing a mechanism to monitor clinical outcomes and assure timely dialysis.

An analysis of limb-threatening lower extremity wound complications after 1090 consecutive coronary artery bypass procedures.

The objective of this study was to examine and characterize limb-threatening lower extremity wound or soft tissue complications after coronary artery bypass (CABG) and determine risk factors for their cause. While minor wound problems of the leg after CABG are not uncommon, serious limb-threatening complications, though less frequent, do occur and are often de-emphasized in the surgical literature. A review of 1090 consecutive CABG procedures performed from January 1, 1995 through December 31, 1995 was instituted, which screened for limb-threatening lower extremity wound or soft tissue complications defined as wounds that: required additional surgery for treatment; prolonged the length of stay; or which required lengthy home health nursing for treatment. Minor lymph leaks, leg swelling, infections or wound problems treated as an outpatient were excluded. Of 1090 patients, 54 (5.0%) experienced a limb-threatening lower extremity complication. Complications were categorized as vein harvest incision non-healing (n = 36, 66.7%), decubitus ulceration (n = 11, 20.4%), forefoot ischemia/embolization (n = 10, 18.5%), groin hematoma/abscess (n = 6, 11.1%), severe cellulitis (n = 3, 5.6%), or a combination (n = 12, 22.2%). Statistically significant risk factors by univariate and bivariate analysis for a complication included older age (68 years vs 62 years, p = 0.007), female sex (57% vs 28%, p < 0.001), diabetes (57% vs 33%, p = 0.005) and longer pump time (129 min vs 114 min, p = 0.009). These complications necessitated five major lower extremity amputations and nine revascularization procedures. Chronic lower extremity ischemia from peripheral vascular disease (PVD) was a major contributing factor for the development of wounds in at least 23 (42.6%) of these patients, though suspected in only 10 (43.5%) preoperatively. A non-healing vein harvest incision below the knee of a patient retrospectively found to have inadequate distal circulation for healing occurred in 17 (31.5%) of the total 54 cases. It was concluded that non-healing vein incisions, decubitus ulcers and forefoot ischemic lesions frequently occurring in older diabetic females with undetected pre-existing PVD, comprise the majority of limb-threatening leg complications after CABG. Nearly one-third of the complications may have been avoided had the vein harvest incision not been made at the ankle of a patient with unappreciated PVD.

Nonendarterectomy procedures of the carotid artery: a five-year review.

Although the efficacy of carotid endarterectomy has been well established, nonendarterectomy procedures of the carotid bifurcation have only sporadically been reported. Of 334 consecutive nontraumatic carotid procedures performed on 321 patients from July 1992 until May 1997, 306 (91.6%) were carotid endarterectomies, 14 (4.2%) were carotid-subclavian bypasses/transpositions, and 14 (4.2%) were nonendarterectomy procedures of the carotid artery. These latter 14 cases (nine females and five males; mean age, 63 years) were all symptomatic (neurological or painful mass) and included carotid kink/coil resection (n = 3; 0.9%), endarterectomy and vertebral transposition (n = 2; 0.6%), carotid aneurysm resection (n = 2; 0.6%), carotid body tumor resection (n = 2; 0.6%), carotid stump ligation/external endarterectomy (n = 1; 0.3%), infected/bleeding carotid patch removal with vein graft replacement (n = 1; 0.3%), saphenous vein graft replacement (n = 1; 0.3%), carotid dilatation for fibromuscular dysplasia (n = 1; 0.3%), and descending aorta to carotid bypass (n = 1; 0.3%). With 30 day follow-up complete for all 334 carotid operations, 10 perioperative strokes (2.9%) and five deaths (1.5%) occurred for a combined stroke/death rate of 3.3 per cent. Of the 14 nonendarterectomy carotid artery operations, there were no strokes or deaths; with mean follow-up of 13 months, 13 patients (92.9%) are asymptomatic, patent, and disease-free. Three severe transient cranial nerve (CN) neuropraxias (21.4%), one myocardial infarction (7.1%), and one late death (mesenteric ischemia at 2 months), however, occurred. Although no statistical differences in stroke, death, and stroke/death occurred between the endarterectomy versus the nonendarterectomy group, transient CN injury was more common in the nonendarterectomy group (21.4% versus 4.1%; P = 0.027). Although nonendarterectomy procedures of the carotid bifurcation are infrequently needed, they seem safe, effective, and indicated in selected patients, despite a higher incidence of transient CN injury.

Internal carotid artery patency following common carotid artery occlusion: management of the asymptomatic patient.

Rarely, internal carotid artery (ICA) patency is maintained above a common carotid artery occlusion (CCAO) through collateral flow of the ipsilateral external carotid artery or an aberrant ICA branch. Several small series report excellent results of ICA revascularization in relieving cerebral ischemic symptoms in these patients. The natural history of CCAO with patent ICA in the asymptomatic patient, however, is unknown. The Greenville Memorial Hospital Vascular Teaching Service registry and all carotid duplex scans done in the Greenville Hospital System vascular laboratory from January 1994 through December 1997 were reviewed. Data collection included chart review, phone interviews, and the review of angiograms and duplex scans. This study suggests that carotid duplex is more sensitive for detecting ICA flow after CCAO than routine contrast angiography. It also suggests that while rare in presentation, asymptomatic patients with CCAO and a patent ICA appear to have a benign neurologic course and can probably be observed without a high risk of stroke.

Superficial femoral artery eversion endarterectomy: a useful adjunct for infrainguinal bypass in the presence of limited autogenous vein.

PURPOSE: To evaluate, in a group of technically high-risk patients, the results of infrainguinal revascularization using a conduit constructed with endarterectomized superficial femoral artery (SFA) and available arm or saphenous vein. METHODS: Of 237 consecutive lower extremity vein graft bypass procedures performed in 195 patients from July 1992 through August 1996, 15 SFA eversion endarterectomies (in 10 men and five women; median age, 70 years) were performed and used as a composite bypass conduit with available autogenous vein for the treatment of limb-threatening ischemia. In each case, an occluded SFA was divided 8 to 15 cm distal to its origin, proximally endarterectomized, and sewn end-to-end to a segment of vein to provide adequate conduit length for bypass grafting. Indications for this technique were unavailability of vein as a result of failed previous bypass grafting (n = 10) or previous coronary artery bypass grafting (n = 5). Veins were sewn distally to a below-knee popliteal artery (n = 4; 27%) or tibial artery (n = 11; 73%). RESULTS: Primary patency, secondary patency, and limb salvage rates at 36 months by life table analyses for the 237 grafts were 62.3%, 81.0%, and 77.2%, respectively. The 15 composite SFA-vein bypass grafts had 36-month primary patency, secondary patency, and limb salvage rates of 60.0%, 72.0%, and 65.9%, respectively (mean follow-up, 15 months). Currently, eight of these patients (53%) have patent bypass grafts; two (13%) died at 4 and 18 months after the operation with patent grafts; two (13%) underwent amputations for progressive foot gangrene despite a patent bypass graft; and three (20%) had grafts that thrombosed at 4, 5, and 10 months. Typical hyperplastic intrinsic graft-threatening stenoses developed in two patients (13%) in the SFA segment at 4 and 8 months; they were discovered by routine duplex scan surveillance. CONCLUSION: Composite SFA eversion endarterectomy/vein graft conduits yield acceptable results, behave similarly to other autogenous conduits used for technically high-risk infrainguinal revascularization, and are beneficial when autogenous vein is limited.

Epidural, intrathecal, and patient-controlled analgesic use in a university medical center.

OBJECTIVE: To determine the number and profile of surgical patients receiving epidural, intrathecal, and patient-controlled analgesia. DESIGN: Two-month audit of epidural, intrathecal, and patient-controlled analgesia. SETTING: A 300-bed, tertiary care, university medical center. PATIENTS: All patients undergoing surgery and receiving epidural, intrathecal, or patient-controlled analgesia. RESULTS: Of 1123 operations performed during the two-month audit, 185 patients (16 percent) received one of the three forms of analgesia studied. Sixty-three percent of the 185 patients received patient-controlled analgesia and 33 percent received epidural injections for pain control. The most common types of surgery associated with the use of these specialized pain-control techniques were obstetric/gynecologic, orthopedic, general, urologic, and cardiothoracic. CONCLUSIONS: Specialized forms of analgesia are becoming increasingly common. Our audit defined the number of patients receiving such therapies according to type of surgery. Collection of such information by other institutions should allow for targeted evaluations of cost-effectiveness (e.g., drug use evaluations).

Synthesis of phytoalexins in sorghum as a site-specific response to fungal ingress.

Sorghum produces phytoalexins that are 3-deoxyanthocyanidin flavonoids. The compounds inhibit the growth of phytopathogenic fungi in vitro. The phytoalexins appear to be synthesized in subcellular inclusions within a host epidermal cell that is about to be penetrated by a fungus. This site-restricted synthesis suggests that the phytoalexin response occurs initially in the first cells that come under fungal attack and is not simply a response of cells that surround the original infection site.

Regional anesthesia in the pediatric patient.

Pediatric regional anesthesia has been viewed less favorably in the past because it was often considered an extra and unnecessary procedure. Current anesthesia practice demonstrates that local anesthetic techniques are of great value either as the sole anesthetic or for postoperative analgesia in the pediatric population. This review of literature contrasts the anatomic, physiologic, and pharmacokinetic differences between the pediatric and adult populations regarding regional anesthesia. The advantages and special considerations of the pediatric population also are reviewed. Regional anesthesia in the pediatric patient population does have its benefits and should be considered as an option in the provision of anesthesia in the pediatric age group.

Spontaneous pneumothorax associated with tuberous sclerosis.

Tuberous sclerosis is a rare hereditary anomaly of variable penetrance characterized by adenoma sebaceum, mental retardation, and epilepsy. Pulmonary disease with spontaneous pneumothorax is a rare complication with this disease. We have recently seen two patients with this complication. A review of the literature reveals 17 other patients with spontaneous pneumothorax and tuberous sclerosis. Eight of these died of pneumothorax. Fifty-three percent of the patients, including all those who died, had normal intelligence. The pathological and roentgenographic findings of the disease are discussed. Recommendations for therapeutic management are given.