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Biomedical subjects

E J Harris

Publications and source records attributed to E J Harris.

At least 19 recordsLinked to original sources
PubMed1992

Neurologic deficits following noncarotid vascular surgery.

Neurologic events following noncarotid vascular surgery (NCVS) are considered unpredictable. To test this hypothesis, we reviewed our vascular registry for a 3-year period and identified all patients with new postoperative focal neurologic events (stroke, hemispheric transient ischemic attack [TIA]) within 2 weeks of a category I or II vascular procedure as defined by the American Board of Surgery, exclusive of carotid surgery and arterial trauma. Thirteen of 1,390 NCVS procedures (0.9%) in 13 patients were associated with focal neurologic events. There were 2 TIAs, 10 anterior circulation strokes, and 1 posterior circulation stroke. Twenty-seven percent of strokes were fatal. The neurologic deficit developed in the immediate postoperative period in 31%, more than 4 hours but less than 72 hours postoperatively in 54%, and within 3 to 14 days postoperatively in 15%. Patients with anterior circulation events (group A, n = 12) were compared for variables potentially influencing postoperative stroke with case controls who were selected using a table of random numbers (group B, n = 12). Controls were derived from a pool of all category I or II NCVS procedures recorded in our vascular registry sequentially during the same time period and who were without new neurologic deficits postoperatively. Using Fisher's exact test, comparisons between groups A and B revealed that new anterior circulation neurologic events in vascular surgical patients tended to be associated with intra-abdominal procedures (p less than 0.05), perioperative hypotension (p less than 0.05), and the presence of a greater than or equal to 50% internal carotid artery stenosis ipsilateral to the neurologic event (p less than 0.001). Such information may prove useful in the management of selected patients prior to arterial reconstruction and in operated NCVS patients with postoperative neurologic events.

Aged↗
PubMed1992

Upper extremity arterial bypass distal to the wrist.

Seventeen arterial bypass procedures distal to the wrist have been performed in 13 men and two women at the Oregon Health Sciences University during the past 9 years. Ten patients had traumatic true or false aneurysms of the ulnar artery with digital embolization. Five patients with end-stage renal disease had severe hand and finger ischemia manifested by rest pain or digital ulceration resulting from widespread forearm and hand arterial occlusions. Patients with aneurysms of the ulnar artery underwent excision and reversed autogenous vein grafting (n = 11) from the distal ulnar artery in the forearm to the superficial palmar arch. All the patients with end-stage renal disease had severe occlusive disease of the forearm and hand arteries and underwent a variety of procedures including radial-radial bypass (n = 2), ulnar-ulnar bypass (n = 2), radial-radial bypass with takedown of a Brescia-Cimino fistula (n = 1), and brachial-radial bypass (n = 1). High-quality upper extremity and magnification hand arteriography was essential for operative planning and was available on all patients. Distal saphenous vein from the ankle or foot was the graft source in 16 procedures and basilic vein the source in one procedure. All operations were performed with headlight illumination, optical loupes, fine sutures, and microvascular instruments. There were no operative deaths or major complications. The mean follow-up period was 14 months. Of the 17 grafts, 16 remained patent by clinical and vascular lab criteria. The single occlusion occurred in an ulnar aneurysm bypass and was accompanied only by mild intolerance to cold.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

The association of elevated plasma homocyst(e)ine with progression of symptomatic peripheral arterial disease.

Plasma homocyst(e)ine (the sum of free and bound homocysteine, homocystine, and the mixed disulfide homocysteine-cysteine, expressed as homocysteine) levels were determined by high performance liquid chromatography in 214 patients with symptomatic (claudication, rest pain, gangrene, amputation) lower extremity arterial occlusive disease and/or symptomatic (stroke, cerebral transient ischemic attacks) cerebral vascular disease and in 103 control persons. Mean plasma homocyst(e)ine was significantly higher in patients than in controls (14.37 +/- 6.89 nmol/ml vs 10.10 +/- 2.16, p less than 0.05). Thirty-nine percent of patients (83 of 214) had plasma homocyst(e)ine values greater than control mean + 2 standard deviations. Plasma homocyst(e)ine values were contrasted to age, male sex, diabetes, hypertension, smoking, renal failure, and plasma cholesterol. No difference was found in the incidence and/or level of any of these risk factors when patients with normal plasma homocyst(e)ine were compared to those with elevated plasma homocyst(e)ine, both by univariate and multivariate analysis. Patients with elevated plasma homocyst(e)ine were more likely to demonstrate clinical progression of lower extremity disease and of coronary artery disease, but not of cerebral vascular disease than were patients with normal plasma homocyst(e)ine, and the rate of progression was more rapid (p = 0.002). Progression of lower extremity disease as assessed in the vascular laboratory was also more common in patients with elevated plasma homocyst(e)ine (p = 0.01). We conclude that elevated plasma homocyst(e)ine is an independent risk factor for symptomatic lower extremity disease or cerebral vascular disease or both. Symptomatic patients with lower extremity disease and with elevated plasma homocyst(e)ine also appear to have more rapid progression of disease.

Age Factors↗
PubMed1990

Avoiding coagulopathy in vascular surgery.

The possibility of coagulopathy can be minimized by attending to certain general perioperative details to avoid hypothermia, hypotension-shock, and multiple transfusions. In this paper, we present our protocol for avoiding coagulopathy in vascular surgery. In the past 1 1/2 years, we have used perioperative plasmapheresis in 204 patients undergoing cardiac or aortic peripheral vascular surgery. Autologous platelet-rich plasma is transfused at the completion of the operation after heparin reversal. Our data show an approximate 50% reduction in homologous blood product requirement. Seventy-five percent of patients having aortic surgery received no homologous blood products during their hospital stay. For those undergoing cardiac surgery, there has been about a 45% reduction in the use of homologous blood products. In our experience, autologous platelet-rich plasma not only decreases the risk of transmittable disease, but promotes hemostasis.

Blood Coagulation↗
PubMed1990

Improving survival and limb salvage in patients with aortic graft infection.

A 15-year experience with 38 aortic graft infections, including 15 patients with graft enteric fistulas, is reviewed in order to analyze modern-day surgical results utilizing extra-anatomic bypass and aortic graft excision. Perioperative mortality was 14% during the most recent 7-year interval, which was a notable improvement compared with the earlier time interval (p = 0.06). Extended follow-up of the perioperative survivors demonstrated a 77% cumulative 5-year survival and a 76% cumulative 5-year limb salvage rate. Subsequent axillofemoral graft infection occurred in 22% of survivors and resulted in a significantly higher amputation rate compared with those patients with no axillofemoral graft infection (p less than 0.001). The results suggest good perioperative and long-term survival in patients with aortic graft infection, with excellent limb salvage if subsequent axillofemoral graft infection can be avoided.

Aged↗
PubMed1990

Surgical treatment of distal ulnar artery aneurysm.

In the past 7 years, we have encountered six patients with finger ischemia as a result of digital artery occlusion associated with seven distal ulnar artery aneurysms. Our experience with the management of these patients forms the basis of this report. All patients were men, with a mean age of 29 years, and all experienced repetitive trauma to the involved upper extremity. Each patient presented with the acute onset of cool and painful digits, with no previous history of cold sensitivity or Raynaud's syndrome. None of the patients had any serologic or clinical evidence of autoimmune disease. Angiography revealed occlusion of the ulnar artery on the affected side in two patients and patent ulnar artery aneurysms in the remaining five patients. There was occlusion of multiple common and proper digital arteries in all patients. One patient with bilateral ulnar artery aneurysms underwent operative repair consisting of aneurysm excision and replacement with autogenous vein grafts from the lower extremity. All patients have improved symptoms, and the grafts remained patent over a mean follow-up of 24 months (range: 13 to 57 months). Based on these results, we recommend that excision and grafting be considered for patients with symptomatic patent ulnar artery aneurysms. Selected patients with thrombosed aneurysms with ongoing digital ischemia may also benefit from surgical intervention.

Adolescent↗
PubMed1990

The effects of cooling on human saphenous vein reactivity to adrenergic agonists.

Human saphenous veins were obtained at surgery and assayed immediately (n = 10). The veins were cut into rings, suspended in organ chambers, and connected to force transducers for the recording of isometric tension. One ring served as control whereas others were treated with the alpha 1-adrenoceptor antagonist prazosin (3 X 10(-7) mol/L), or the alpha 2-adrenoceptor antagonist rauwolscine (10(-7) mol/L). In quiescent rings cooling from 37 degrees C to 24 degrees C had no significant effect. Norepinephrine (10(-8)-10(-5) mol/L) caused concentration-dependent contractions with an EC20 (-log concentration of norepinephrine required to induce contractions 20% of maximal) = 6.97 +/- 0.10. The contractions were inhibited by prazosin (EC20 = 5.89 +/- 0.17, p less than 0.001) and rauwolscine (ED20 = 5.78 +/- 0.11, p less than 0.001). In control rings cooling potentiated contractions evoked at concentrations of norepinephrine below 10(-6) mol/L and inhibited those at higher concentrations. In rings treated with alpha-antagonists cooling depressed the maximal contractile responses. Contractions to the alpha 1-agonist, phenylephrine (10(-7)-10(-4) mol/L), were inhibited by cooling, whereas those to the alpha 2-specific agonist B-HT 920 (10(-7)-10(-4) mol/L) showed a pattern similar to that seen with norepinephrine. The data indicate that the human saphenous vein possesses both alpha 1- and alpha 2-adrenoceptors postjunctionally, and that both contribute to contractile responses. Cold augments saphenous vein reactivity to norepinephrine by an apparent increase in the responsiveness of alpha 2-adrenoceptors to agonists. The relationship between temperature and adrenoceptor responsiveness may be of pivotal importance in defining the mechanism of cold-induced vasospasm.

Cold Temperature↗
PubMed1990

Clinical results of axillobifemoral bypass using externally supported polytetrafluoroethylene.

Seventy-six axillobifemoral grafts with externally supported polytetrafluoroethylene prostheses were performed since 1983. The indications for operation were absolute (aortic sepsis) in 20 (26%) patients and relative (excessive operative risk or technical difficulty) in 56 (74%) patients. The life-table primary patency for these operations at 4 years follow-up (mean follow-up, 2 years, 4 months) was 85%. We conclude that the patency results achieved in this patient series are sufficiently satisfactory to warrant use of axillobifemoral grafts in an expanded number of patients with high operative risk and need for bypass of aortoiliac occlusive disease.

Aged↗
PubMed1990

The importance of routine surveillance of distal bypass grafts with duplex scanning: a study of 379 reversed vein grafts.

To assess the utility of routine duplex surveillance, 379 infrainguinal reversed vein grafts performed at two independent teaching hospitals were prospectively entered into a surveillance protocol from March 1986 through August 1989. An average of 3.2 postoperative duplex graft flow velocity (GFV) measurements per graft was obtained during a mean follow-up interval of 21 1/2 months. Only 2.1% of 280 grafts with GFV measurements greater than 45 cm/sec failed within 6 months of a normal surveillance examination. GFV measurements less than 45 cm/sec in 99 grafts led to arteriography in 75 grafts, identifying 50 stenotic lesions in 48 bypasses (12.6% of series). Inflow lesions were present in 5%, outflow stenoses in 2%, and intrinsic graft stenoses in only 6% of bypasses. Only 29% of grafts identified as failing by duplex scan were associated with a reduction in ankle-brachial index of greater than 0.15. Secondary reconstructions were performed in 48 grafts based on detection of a reduced GFV measurement; all such reconstructions are patent after a mean follow-up of 5 months. Duplex surveillance is more reliable in identification of failing vein grafts than is determination of ankle-brachial index.

Adult↗
PubMed1989

The plasma collection system: a new concept in autotransfusion.

We have used the Haemonetics Cell-Saver autotransfusion technique in over 6,500 cases since 1979, salvaging more than 11,000 units of packed red blood cells. Major utilization has been in cardiac, vascular, and orthopedic cases. Coagulopathy associated with hypothermia, shock, multiple transfusions, and the autotransfusion technique, which removes clotting factors and platelets, often necessitated use of fresh-frozen plasma and platelet packs postoperatively to control bleeding and clotting problems. However, this defeats the prevention of disease transmission, transfusion reaction, and autoimmunization. Haemonetics has recently developed a plasma collection system which salvages up to 1,000 cc of platelet-rich plasma. Early experience suggests this technique will not only decrease the incidence of postoperative bleeding but further decrease the use of homologous (bank) blood and components. A step-by-step guide to the plasma collection system is discussed. The plasma collection system augments the present autotransfusion technique that conserves red blood cells, thus making complete autologous blood transfusion a reality.

Blood Transfusion, Autologous↗
PubMed1989

Epithelioid hemangioendothelioma of the external iliac vein: a primary vascular tumor presenting as traumatic venous obstruction.

A 32-year-old man employed as a laborer presented with the signs and symptoms of iliofemoral venous obstruction of 1 months' duration. Results of initial phlebography from the ankle to the femoral area were normal. No iliac vein anatomy was seen. This led to a group of tests directed toward neuromuscular function, which were unrewarding. On referral to our institution a noninvasive venous vascular laboratory examination was performed, which clearly indicated iliac vein obstruction/stenosis, with a normally patent distal venous system. Subsequent repeat phlebography, including direct femoral vein injection, visualized a mass lesion partially occluding the iliac vein. This lesion was treated with primary excision and segmental venous replacement with an interposition graft of autogeneous internal jugular vein. The excised lesion proved to be an epithelioid hemangioendothelioma of the iliac vein.

Adult↗
PubMed1989

Short limb and the ball-and-socket ankle deformity.

Congenital ball-and-socket ankle deformity is a complex pediatric orthopedic deformity that usually is associated with a short limb, a short fibula, distal tibial dysplasia, rearfoot coalition, and ray deficiency. The author reviews the literature on this orthopedic complex, presents two cases, and discusses the practical clinical management of this syndrome.

Abnormalities, Multiple↗
PubMed1988

A comparative study of the clinical presentation of tarsal coalitions.

Twenty patients have received the radiographic diagnosis of tarsal coalition. Seven were talocalcaneal (35 per cent), seven were calcaneonavicular (35 per cent), and six were talonavicular (30 per cent). The average age at time of diagnosis was 19.3 years for talocalcaneal coalition, 14.7 years for calcaneonavicular coalition, and 15.2 years for talonavicular coalition. Bilateral involvement was seen in more than half of the talocalcaneal and talonavicular coalitions. Symptoms were more severe in talocalcaneal and calcaneonavicular coalitions. All patients in these two groups had pain. Talonavicular coalitions either were asymptomatic (picked up on radiographs taken for other complaints) or were associated with painful medial navicular masses. In our study, five of the six patients (81 per cent) had this mass. We report a surprisingly high number of talonavicular coalitions for such a small group. In studies based on the investigation of peroneal spastic flatfoot, this form of coalition is not as frequently encountered. This suggests that talonavicular coalitions may be much more common than the literature to date has suggested.

Adolescent↗
PubMed1986

The cell-saver and autologous transfusion: an underutilized resource in vascular surgery.

The vascular surgeon's best resource for blood transfusion is the patient's own blood. It is readily available for recycling, already precisely typed and crossmatched, and without the risk of transfusion-related diseases such as hepatitis and AIDS. The relative ease, safety, and cost-effectiveness of autologous blood transfusions, intraoperative autotransfusions, and postoperative autotransfusions has been shown in our hospital experience with 320 cases and in the literature. We predict that autologous donor blood and autotransfusion will soon be widely accepted and utilized as the best and safest method of blood replacement.

Blood Transfusion, Autologous↗
PubMed1985

Arterial thromboembolism. A 20-year perspective.

Our experience with 739 patients with lower extremity thromboembolism since the advent of the balloon catheter has led us to several important observations: As the etiology has shifted from rheumatic to atherosclerotic, we treat a more complex group of patients, one fourth of whom have severe, preexisting peripheral occlusive disease. Early diagnosis and treatment is essential to decrease the mortality and morbidity, which has ranged about 25% +/- 10%. Anticoagulation must be continued in the postoperative period, accepting wound hematomas as a fair "trade-off" to prevent recurrent embolus and distal thrombosis in areas inaccessible to the catheter. Postoperative use of heparin "buys time" to further assess marginal results of embolectomy allowing arteriography and careful planning of secondary operations to assure not only a viable but a functional limb. There is little mention in the literature to emphasize this approach, which we think is essential for long-term salvage. Early in the series, patients were treated with heparin or embolectomy alone. There were 161 secondary operations in 135 patients following embolectomy consisting of repeated thromboembolectomy, popliteal exploration, sympathectomy, bypass graft(s), angioplasty, and endarterectomy. Additionally, 44 patients had a direct attack correcting the cardiac source of their embolism. Our overall mortality (12%) and limb salvage (95%) shows marked improvement compared with earlier reports. Therefore, we recommend combined embolectomy and heparin as the primary choice of therapy.

Adult↗
PubMed1981

Stimulation of calcium-ion efflux from liver mitochondria by sodium ions and its response to ADP and energy state.

The Ruthenium Red-insensitive efflux of Ca2+ from previously loaded rat liver mitochondria was studied as a function of the added Na+ concentration and ADP present. Stimulation of Ca2+ efflux is sigmoidally dependent on the Na+ concentration; maximal stimulation of efflux was observed with 12--15 mM-NaCl. Na+-stimulated Ca2+ efflux from liver mitochondria is about one-tenth that from cardiac mitochondria. No synergistic effect of K+ on the Na+-stimulated efflux was found. The alkali-metal cations other than Na+ did not stimulate efflux and did not prevent stimulation by Na+. In the absence of Na+, Ca2+ efflux was diminished by added ADP, but the Na+-stimulated efflux was made correspondingly greater as ADP concentration was increased to 16 microM. The Na+-stimulated Ca2+ efflux was inhibited by 70% by oligomycin and was not observed in the presence of antimycin. It is suggested that failure to observe Na+-stimulation of Ca2+ efflux from liver mitochondria by some investigators is attributable to a high basal efflux existing before addition of the Na+ salt.

Adenosine Diphosphate↗
PubMed1980

Uptake of safranine by cardiac mitochondria. Competition with calcium ions and dependence on anions.

Some characteristics of the energized uptake of safranine by rat heart mitochondria were studied. When monitored by changes in differential absorbance (between 524 and 554 nm) of a whole suspension in safranine-containing medium, the changes seen are not linearly related to the quantity of the safranine moving. It happens coincidentally that the changes observed are nearly linearly related to the logarithm of the ratio between the accumulated safranine and its residual concentration in the medium; this explains why the changes of absorbance have been found by other authors to be linearly related to the logarithms of the ratio of internal/external concentrations of such other cations as are permeable. The uptake process appears to compete for energy with Ca2+ uptake and vice versa. Energized safranine uptake has an anion requirement, which is seen when movement of endogenous Pi has been inhibited; the small residual safranine uptake obtained when energy is provided in the presence of mersalyl may be attributable to internal Pi. However, a limited anion-independent energized uptake of safranine, in exchange for internal K+, may be elicited in the presence of nigericin. Adding ATP to the energized system in the presence of an inhibitor of Pi movement elicits an additional uptake of safranine that is oligomycin-sensitive and that probably arises on account of generation of internal Pi by hydrolysis of the entering ATP.

Adenosine Triphosphate↗