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Biomedical subjects

J J Schuler

Publications and source records attributed to J J Schuler.

At least 19 recordsLinked to original sources

A comparison of operative approaches and parameters predictive of success in multilevel arterial occlusive disease.

BACKGROUND: The correction of abnormal inflow alone in patients with multilevel arterial occlusive disease (MLAOD) may be inadequate to relieve limb-threatening ischemia. This study was undertaken to compare operative approaches and attempt to define preoperative parameters predictive of limb salvage in patients with MLAOD. STUDY DESIGN: The outcome after revascularization for 194 patients with limb-threatening ischemia MLAOD was assessed retrospectively. One hundred fifty-one patients initially underwent an inflow operation alone. Based on whether or not these patients required an outflow operation within one year, they were divided into two groups: group 1, no outflow operation (121 patients, 121 limbs), and group 2, outflow operation required for continued ischemic symptoms (30 patients, 30 limbs). A separate group of forty-three patients (43 limbs) underwent synchronous inflow-outflow operations, or multilevel revascularization, as their initial operative procedure (group 3). RESULTS: Perioperative complications and mortality rates did not differ between groups. Limb salvage rates were similar for groups 1 and 3, whereas in group 2, limb salvage rates were significantly reduced (p = 0.0184). Long-term limb salvage after an isolated inflow procedure was associated with lack of prior vascular reconstructions (p = 0.0002), the absence of tissue loss (p = 0.0019), and an infrageniculate angiographic runoff score of less than 6 (p = 0.054). CONCLUSIONS: In patients with limb-threatening MLAOD, synchronous inflow-outflow operations can be performed with resultant morbidity and mortality rates comparable with inflow alone. After an inflow operation, the approach of "expectant management" may ultimately compromise limb salvage if a subsequent outflow operation is required.

Adult

Fetal haemoglobin levels in adult type 1 (insulin-dependent) diabetic patients.

Glycated haemoglobin levels (HbA1 and HbA1c) are established parameters of long-term glycaemic control in diabetic patients. Depending on the method used, fetal haemoglobin interferes with the assays for glycated haemoglobin. If present in high amounts, fetal haemoglobin may lead to overestimation of glycated haemoglobin levels, and therefore, of average blood glucose concentration in diabetic patients. Glycated (HbA1c) and fetal haemoglobin levels were measured by high pressure liquid chromatography in 60 (30 female) adult Type 1 (insulin-dependent) diabetic patients of Swiss descent, and were compared with levels obtained from 60 normal, non-diabetic control subjects matched for age and sex. Fetal haemoglobin levels were significantly higher in the diabetic patients (0.6 +/- 0.1%, mean +/- SEM; range: 0-3.6%) than in the control subjects (0.4 +/- 0.1%, p < 0.001). Elevated fetal haemoglobin levels (> or = 0.6%) were found in 23 of 60 diabetic patients (38%) compared to 9 of 60 control subjects (15%; chi 2 = 8.35, p < 0.01). In addition, fetal haemoglobin levels in diabetic patients are weakly correlated with glycated haemoglobin (HbA1c) (r = 0.38, p < 0.01). Fetal haemoglobin results were confirmed with the alkali denaturation procedure, and by immunocytochemistry using a polyclonal rabbit anti-fetal haemoglobin antibody. A significant proportion of adult patients with Type 1 diabetes has elevated fetal haemoglobin levels. In certain patients this may lead to a substantial over-estimation of glycated haemoglobin levels, and consequently of estimated, average blood glucose levels. The reason for this increased prevalence of elevated fetal haemoglobin remains unclear, but it may be associated with poor glycaemic control.

Adolescent

Acute ischemic proctitis. Report of six cases.

Acute ischemic proctitis is a rare clinical entity caused by vascular insufficiency of the major or collateral circulation to the rectum. It usually occurs following aortic or aortoiliac operations. Six patients with acute ischemic proctitis are presented; four cases occurred after direct arterial interruption, one after accidental embolization of the blood supply to the rectum, and one from tumor edema. Bloody diarrhea was the most common symptom. Loss of anal sphincter tone was also an early sign in three patients. The diagnosis of ischemia was made by mucosal appearance on proctosigmoidoscopy and is differentiated from infectious proctitis by stool culture. Superficial mucosal ischemia was treated without surgery, but deeper levels of necrosis required laparotomy and Hartmann's resection. Rectal excision was not necessary. Four patients survived the ischemic event.

Acute Disease

Long-term results of venous reconstruction after vascular trauma in civilian practice.

The natural history of venous reconstruction (VR) in terms of patency and clinical outcome after vascular trauma has not been well documented. This study consists of 32 patients who had VR performed for extremity vascular trauma and were available for long-term assessment (mean follow-up time 49 months, range 6 to 108 months). The types of repair performed were as follows: lateral venorrhaphy (simple repair) (56%), interposition grafting (22%), patch repair (12.5%), and end-to-end repair (9.5%). Seventeen patients underwent venography after the operation with documentation of repair patency in eight patients (46%) and thrombosis in nine (54%). Only two patients had significant clinical edema at follow-up examination. Noninvasive venous evaluation consisted of Doppler ultrasonography, impedance plethysmography, photoplethysmography, and color-flow duplex scanning (CFDS). The photoplethysmography-derived venous refilling time of the injured extremity was 34.9 +/- 16.2 seconds whereas that of the contralateral noninjured extremity was 36.8 +/- 16.1 seconds (p = 0.5). Based on standard criteria for CFDS, 90% of VRs were patent. Eight repairs that were patent in the early postoperative period remained patent on CFDS. Of the nine repairs with early thrombosis, eight were assessed as patent on follow-up CFDS. In conclusion, VR is a durable surgical procedure associated with minimal morbidity, good long-term patency, and preservation of venous competence. The natural history of thrombosed VRs appears to be one of thrombus absorption with recanalization.

Adolescent

A nine-year experience with crossover femoro-femoro-popliteal sequential bypass.

Multisegmental arterial occlusive disease may require a combined inflow and outflow procedure for optimal treatment of limb ischemia. Twenty-one patients with unilateral iliac artery stenosis or occlusion and ipsilateral superficial femoral artery occlusion underwent crossover femoro-femoro-popliteal sequential bypass during a 9-year period. Seventeen operations were for limb salvage. Patency rates were determined separately for each segment of the bypass. Primary patency rates for the femoro-femoral segment were 89%, 83%, and 57% at 1, 2, and 5 years, respectively. Primary patency rates for the femoro-popliteal segments were 68%, 62%, and 40% at 1, 2, and 5 years, respectively. Limb salvage rates were 100%, 90%, and 77% at 1, 2, and 5 years, respectively. This experience indicates that femoro-femoro-popliteal bypass is an effective treatment in selected patients with severe ischemia due to combined iliac artery and superficial femoral artery disease.

Aged

Autogenous vein graft repair of injured extremity arteries: early and late results with 134 consecutive patients.

Autogenous vein tissue is recognized as the preferred material for extremity revascularizations that require the use of a conduit. However, the results after vascular repair of injured extremity arteries with autogenous vein interposition or bypass grafts have not been well defined. This study was done to determine both the early and late patency and limb salvage rates as well as the graft infection rate of autogenous vein repairs of injured extremity arteries. The records of 134 consecutive patients with acute extremity arterial injuries requiring repair with a reversed autogenous vein graft over a recent 5-year period were reviewed. Follow-up graft patency was defined by the presence of a palpable pulse and an extremity Doppler-derived pressure index of greater than or equal to 0.9 distal to the arterial repair. Cumulative patency was assessed by the life-table method. Acute graft thrombosis occurred in two patients, one of whom underwent successful graft thrombectomy. Four patients (3%) required extremity amputation: one patient with a thrombosed vein graft and three patients with patent vein grafts but nonsalvageable limbs as a result of myonecrosis (2) or osteomyelitis (1). No perioperative graft infections occurred. One hundred twenty-eight patients (97%) had an intact extremity and a patent vein graft at the time of hospital discharge. One hundred three patients (80%) were examined at 30 days, and all grafts were patent. Seventy-three patients (57%) were available for follow-up at intervals exceeding 6 months, and 40 patients (31%) were followed-up for periods exceeding 24 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

The natural history of intimal flaps in a canine model.

The natural history of arterial intimal flaps has not been well defined. This study characterizes the natural history of unrepaired intimal flaps. Thirty-nine 1-, 2-, and 3-mm hemispheric, distally based intimal flaps were made in 4- to 5-mm diameter canine femoral and carotid arteries. Twenty arteries had 2- and 3-mm intimal flaps and were monitored for short-term arterial thrombosis and flap extension. Nineteen had 1- and 2-mm intimal flaps and were monitored for thrombosis, long-term development of neointimal hyperplasia, arterial stenosis, and persistence of the flap. While 40% of the arteries with 3-mm intimal flaps developed thrombosis in 3 to 5 days, only 3% of the arteries with 1- or 2-mm intimal flaps developed thrombosis. Most 1- to 2-mm intimal flaps resolved and the subsequent development of neointimal hyperplasia or arterial stenosis was minimal. Arteries with hemodynamically significant stenoses from intimal flaps warrant repair, while arteries with smaller intimal flaps may not require repair.

Animals

A rapid, accurate, noninvasive technique for diagnosing critical and subcritical stenoses in aortoiliac arteries.

Accurate hemodynamic evaluation of the aortoiliac system for the purpose of determining the need for an inflow procedure currently requires invasive pressure measurements. This study was undertaken to evaluate a noninvasive technique with the aortofemoral transfer function. Twenty-eight human aortoiliac segments were studied with intraarterial pressure measurements, with and without papaverine injection, and by calculation of the Doppler-derived mean power frequency index obtained by digital signal processing of aortic and femoral spectra. The procedure is menu driven and can be performed by any duplex ultrasound technologist. This technique involves recording 20 aortic and 20 femoral Doppler signals, requiring less than 1 minute of data acquisition time. Intraarterial pressure measurements were used to classify arteries into the three following groups: (1) normal arteries, (2) arteries with subcritical stenoses, and (3) arteries with critical stenoses. The mean power frequency index of group 1 arteries (n = 7) was 0.63 +/- 0.04, of group 2 arteries (n = 6) was 0.46 +/- 0.02, and of group 3 arteries (n = 15) was 0.21 +/- 0.05. These mean power frequency index values were significantly different by analysis of variance (ANOVA) (p less than 0.0001). Each group could be differentiated from the other groups with a sensitivity of 0.83 to 1.00, a specificity of 1.00, and an accuracy of 0.92 to 1.00 compared to intraarterial pressure measurements, including papaverine testing. Measurement of the mean power frequency index is a rapid, noninvasive technique that diagnoses and quantifies aortoiliac stenoses with an accuracy similar to intraarterial pressure measurements.

Aortic Diseases

The role of isolated profundaplasty for the treatment of rest pain.

This study was undertaken to determine the efficacy and durability of profundaplasty and define preoperative factors predictive of success. The hospital charts, vascular laboratory data, and arteriograms of 20 patients having 21 isolated profundaplasties for ischemic rest pain between 1979 and 1987 were reviewed. Follow-up extended to 72 months (mean, 26 months). Early success was achieved in 12 extremities (57%) and life-table analysis showed continued success to six years in 11 extremities (55%). Of the multiple preoperative factors assessed, only a low-thigh/ankle gradient pressure index (TAGI) of less than 0.55 was predictive of success. Life-table analysis for limbs with a TAGI of less than 0.55 showed an 89% success rate at six years compared with only a 32% success rate for limbs with a TAGI of more than 0.55. Isolated profundaplasty for the treatment of ischemic rest pain can be an efficacious and durable procedure when patients are selected based on objective hemodynamic measurements.

Arteries

Open transmetatarsal amputation in the treatment of severe foot infections.

Severe forefoot infections may lead to limb loss, even if addressed aggressively. Infection or gangrene that compromises the plantar skin flap may preclude a standard transmetatarsal or midfoot amputation, thereby culminating in a below-knee amputation. We report a series of forefoot infections with loss of the distal plantar skin. Open or guillotine amputation at the mid-metatarsal level led to a high rate of healing and a durable stump, provided that the level of infection did not extend beyond the metatarsal heads. Wound closure was obtained by wound contracture alone or by use of partial-thickness skin grafting. Rehabilitation was dependable. The association of diabetes mellitus or gangrene did not adversely affect outcome. Open transmetatarsal amputation is a safe surgical option preferable to midfoot or below-knee amputation for the treatment of severe forefoot infection that does not extend proximally beyond the metatarsal heads.

Amputation, Surgical

Hypercoagulable states and lower limb ischemia in young adults.

This study prospectively evaluates hypercoagulable states in patients under 51 years of age undergoing lower extremity revascularization for ischemia and assesses early outcome after operation. Twenty patients whose ages range from 23 to 50 years (mean 40.8 years) were identified prospectively who underwent lower extremity revascularization and evaluation of hypercoagulability. Fifteen patients were male (75%), 10 were black (50%), six had hypertension (30%), and four were diabetic (20%). All but two were cigarette smokers (90%). Seven aortoiliac procedures and 13 infrainguinal procedures were performed. Six patients had one or more abnormalities of regulatory proteins (protein S deficiency, four; protein C deficiency, three; presence of lupus-like anticoagulant, three; plasminogen deficiency, two). Eight of 17 patients in whom platelet aggregation profiles were obtained showed increased reactivity (47%). Only 4 of 17 patients (24%) were normal when tested for all parameters. Arterial or graft thrombosis developed in four of the 20 patients within 30 days after operation. Hypercoagulability was found in all four patients whose revascularizations failed. A high incidence of hypercoagulable states was found in patients under 51 years of age with lower limb ischemia requiring revascularization. Hypercoagulability may have contributed to early postoperative thrombosis of the vascular procedure.

Adult

The fate of unrepaired minor technical defects detected by intraoperative ultrasonography during carotid endarterectomy.

This report describes the natural history of unrepaired minor technical defects detected by intraoperative B-mode ultrasonography during carotid endarterectomy. Intraoperative ultrasonography was used to assess the technical adequacy of 80 carotid endarterectomies. Sixty-two arteries were normal on intraoperative ultrasound examination, whereas the remaining 18 arteries had a total of 21 minor residual technical defects. The 21 minor defects consisted of four internal carotid artery lesions, nine common carotid artery lesions, and eight external carotid artery lesions, 19 had 1 to 3 mm intimal flaps, and two had small stenoses. Sixteen of the 19 intimal flaps resolved before the first postoperative ultrasound study. These arteries had normal examination results, which indicated that these intimal flaps had healed. The two stenoses detected intraoperatively could not be detected by postoperative carotid duplex scanning at 1 month follow-up. No statistically significant relationship was found between the presence of a minor residual defect on intraoperative ultrasonography and the subsequent development of recurrent stenosis or occlusion in any of the arteries assessed. These data suggest that certain minor technical defects in the carotid artery that were detected by intraoperative ultrasonography are benign and may not require repeat exploration of the carotid artery for repair.

Actuarial Analysis

The use of sartorius muscle rotation-transfer in the management of wound complications after infrainguinal vein bypass: a report of eight cases and description of the technique.

Although rare, major wound breakdown after infrainguinal bypass resulting in vein graft exposure carries the risk of vein graft disruption with threat to both life and limb. The use of sartorius muscle rotation-transfer specifically in the management of exposed autogenous infrainguinal vein grafts has not been previously described. Eight patients were evaluated for major wound disruption resulting in graft exposure after infrainguinal vein bypass. Soft tissue coverage was provided in all eight cases by means of a distally based sartorius muscle rotation flap. There was no instance of postoperative death, graft thrombosis, secondary hemorrhage, or persistent infection. Late follow-up has shown continued satisfactory results. We conclude that effective soft tissue coverage and salvage of exposed infrainguinal vein bypass grafts can be accomplished in selected cases by means of sartorius muscle rotation-transfer.

Adult

Lupus-like anticoagulants and lower extremity arterial occlusive disease.

Lupus-like anticoagulants (LLA), lupus anticoagulant and/or anticardiolipin antibody, are increasingly recognized in association with venous and arterial thrombotic events. We recently reviewed our experience with patients undergoing revascularization for lower-limb ischemia who were found to have LLA. Nine patients had LLA based on a prolongation of the partial thromboplastin time or by anticardiolipin assay by an enzyme-linked immunosorbent assay system. The ages of the patients ranged from 23 to 57 years. There were seven (78%) men, six (67%) blacks, two (22%) diabetic patients, and three (33%) hypertensive patients. One patient had systemic lupus erythematosus. All patients except one were cigarette smokers. Four patients had concurrent regulatory protein abnormalities: three protein C deficiencies, one protein S deficiency, and one plasminogen deficiency. The nine patients had 10 lower-extremity arterial reconstructions with two postoperative failures within 30 days. Patients were anticoagulated with heparin or aspirin after all but one operation. Patients at risk were identified on the basis of age (less than 51 years), unexplained early graft thrombosis, or history of venous or arterial thrombotic events. This group of patients is believed to be at risk for early postoperative thrombosis. Postoperative anticoagulation after revascularization for patients with LLA may be beneficial.

Adult

Risk factors affecting the natural history of intermittent claudication.

To determine the prognostic significance of the level of arterial disease in claudicators, risk factors affecting the progression of intermittent claudication, including hemodynamic variables obtained from noninvasive vascular laboratory examinations, were assessed. We identified 378 patients with intermittent claudication by characteristic history and the presence of abnormal treadmill exercise examination results. Results of serial examinations were available for 195 of these patients, who had 310 claudicating limbs. Life-table analysis revealed that after eight years, 41% of these patients had progressed to critical ischemia, defined as rest pain or tissue loss, and 50% had died. Cox proportional hazards general linear regression analysis found that at a patient's first examination in the vascular laboratory, the ankle-brachial index and the decrease in ankle-brachial index after exercise were significantly associated with the subsequent development of critical ischemia. The level of disease at the initial examination in the vascular laboratory was not a significant risk factor for progression to critical ischemia and therefore should not be used as an indicator for or against operation in patients with intermittent claudication.

Adult

Analysis of 18 recent cases of penetrating injuries to the common and internal carotid arteries.

Penetrating injuries to the common and internal carotid artery carry the unique potential for irreversible neurologic damage, respiratory collapse, and exsanguination. This study analyzes a recent 4 year experience with 18 cases of penetrating injury to the carotid artery to identify the factors influencing surgical decision-making, perioperative complications, and mortality. Sixteen patients with acute respiratory distress required emergent airway intubation. Three patients in hemorrhagic shock were brought directly to the operating room; the remaining 15 underwent emergency carotid arteriography. Three patients with multiple intramediastinal vascular injuries exsanguinated on the operating table before hemorrhage could be controlled. There were no deaths or neurologic complications in the 14 surviving patients who had an operation on the carotid artery, including 2 patients treated by internal carotid artery ligation. Early control of the airway was the most common initial requirement in this group of patients. Judicious use of preoperative arteriography was thought to facilitate the operative approach in selected patients. A flexible surgical approach to the damaged carotid artery is essential based on the patient's hemodynamic status, degree of neurologic impairment, and nature and extent of arterial damage.

Adolescent

Long-term results of infragenicular bypasses with autogenous vein originating from the distal superficial femoral and popliteal arteries.

Forty-nine bypasses originating from the distal superficial femoral artery or popliteal artery in 46 patients were reviewed to examine late patency, limb salvage, and factors leading to graft failure. Operations were performed because of tissue loss in 86%, rest pain in 12%, and limiting claudication in 2% of limbs. Proximal anastomosis was from the distal superficial femoral artery in 12% and the popliteal artery in 88%. Distal anastomosis was to the below-knee popliteal artery or proximal tibial vessels in 20% and the distal tibial vessels in 80%. Life-table analysis showed a primary patency rate of 83%, 62%, and 41%, at 1, 3, and 5 years, respectively. The rate of limb salvage at 6 years for all grafts was 69%. Cox proportional hazards analysis determined that stenosis of 20% or greater in the proximal superficial femoral artery before bypass was a significant risk factor for graft failure (p = 0.02) despite the presence of normal intra-arterial pressure at the site of the proximal anastomosis at the time of bypass. Long-term survival in these patients was low, with a 6-year survival rate of only 24%. Infragenicular bypasses originating from the distal superficial femoral artery or the popliteal artery can be performed with patency and limb salvage rates comparable to bypasses originating from the common femoral artery. These bypasses are more likely to fail when performed in the presence of a stenosis 20% or greater in the superficial femoral or popliteal artery proximal to the graft origin.

Aged

In situ tibial reconstruction. State-of-the-art or passing fancy.

To further evaluate the efficacy of in situ saphenous vein bypass, the authors have reviewed their experience with in situ bypass. Between October 1981 and December 1985, 120 in situ saphenous vein bypass were performed; 81 were to infrapopliteal vessels. All procedures were performed for limb salvage. The mean patient age was 74 years, and 74% were men, 57% had diabetes mellitus, 92% were smokers, and 72% had hypertension and/or coronary artery disease. All patients were evaluated by preoperative noninvasive testing and biplanar angiography. All procedures were performed by the valve incision technique. The vein utilization rate was 91%. Grafts were routinely placed into isolated tibial segments and foot vessels without evidence of a patent pedal arch. Follow-up information was obtained at 3-month intervals. Patency and limb salvage data were calculated by life-table analysis. The cumulative patency rates were 98% at 1 month, 88% at 12 months, and 82% at 50 months. These data demonstrate that the in situ bypass maintains an excellent patency rate and provides durable limb salvage.

Aged