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Biomedical subjects

W H Wagner

Publications and source records attributed to W H Wagner.

At least 37 records · Page 2Linked to original sources
PubMed1990

Objective measurement of limb perfusion by dermal fluorometry. A criterion for healing of below-knee amputation.

Quantitative fluorometry has been recommended as an accurate adjunct to clinical judgment in the preoperative assessment of lower-extremity amputation level. In this prospective study of 56 patients who had below-knee amputation, clinical judgment was used as the sole criterion for site selection. Quantitative fluorometry was compared with clinical judgment in a prospective, blinded study. All patients were studied before amputation with administration of intravenous fluorescein. Fifteen minutes after injection, objective measurement of dye fluorescence was performed at multiple sites with a quantitative fluorometer, and a dye fluorescence index was derived. All limbs undergoing amputation were ischemic, manifested by rest pain, nonhealing ulcers, or gangrene. Five patients (8.7%) failed to heal at the below-knee level. The mean dye fluorescence index for the group that healed was 81 +/- 51 (range, 13 to 259) and for the group that failed to heal, 110 +/- 49 (range, 70 to 195). Objective measurement of fluorescein perfusion did not correlate with amputation healing at the below-knee level in our patient population.

Adult↗
PubMed1990

Angioscopy for intraoperative management of thromboembolectomy.

Our experience with angioscopy suggests that direct visualization of the arterial lumen during thromboembolectomy procedures would provide a more reliable method of assessing luminal morphologic characteristics than angiography alone. We inspected 32 grafts (seven aortobifemoral, 18 infrainguinal bypass, and seven dialysis access fistula grafts) in 32 patients. Thirty-one patients had thrombotic events and one patient had an acute embolus. Angioscopy following standard catheter thrombectomy revealed significant amounts of retained thrombus or neointima in all thrombectomies. Angioscopic information from 18 patients with an infrainguinal bypass graft led to graft revision in six cases and placement of a new graft in 10 cases. One graft limb was replaced in seven aortobifemoral grafts, and multiple repeated thrombectomies were employed to extract debris in the remaining six cases. Repeated graft thrombectomy was also beneficial in dialysis access fistulas. Angioscopy allowed us to omit the completion angiogram and led to an improved technical result. We conclude that angioscopy is useful during thromboembolectomy procedures.

Aged↗
PubMed1990

The influence of neutralizing heparin after carotid endarterectomy on postoperative stroke and wound hematoma.

The influence of neutralizing or not neutralizing heparin after carotid endarterectomy on postoperative stroke and wound hematoma is unknown. During the past 6 years some of the authors frequently gave protamine sulfate to neutralize heparin, whereas others did not unless a patch was used or wound hemostasis was not readily obtained. To determine the influence of protamine sulfate on stroke and wound hematoma the records of 697 patients having a carotid endarterectomy from January 1984 to September 1989 were reviewed. Protamine sulfate was given to 328 patients, and 369 did not receive protamine sulfate. The incidence of stroke in the two groups was 1.8% (n = 6) and 2.7% (n = 10), respectively, and the difference was not significant (p = 0.6019). Excluding three strokes that could not be related to neutralizing or not neutralizing heparin, the difference remained insignificant (1.5% vs 2.2%, p = 0.7290). The incidence of wound hematoma was 1.8% (n = 6) in patients given protamine sulfate and 6.5% (n = 24) in patients not given protamine sulfate, and this difference was significant (p = 0.0044). The difference remained significant when three hematomas not related to protamine sulfate were excluded (1.2% vs 6.2%, p = 0.0013). In patients not given protamine sulfate draining the wound lessened the incidence of wound hematoma (4.4% vs 8.6%), but this difference was not statistically significant (p = 0.1475). In patients given protamine sulfate the dose of protamine sulfate (15 to 45 mg vs 50 to 75 mg) had no statistically significant effect on the incidence of stroke (0.8% vs 2.0%, p = 0.6530) or wound hematoma (1.6% vs 1.0%, p = 1.000).

Aged↗
PubMed1989

Comparison of contrast arteriography to arterial mapping with color-flow duplex imaging in the lower extremities.

Color flow duplex scanning was used to "map" the iliofemoral and femoral popliteal segments in 61 patients (84 extremities) undergoing evaluation for excimer laser angioplasty. Eight locations, iliac, common femoral, profunda femoris, proximal and distal superficial femoral artery, proximal and distal popliteal, and tibioperoneal trunk were scored as normal versus abnormal, greater than 50% stenosis, or occluded, and occlusions were measured in centimeters. Specificity, sensitivity, and accuracy were calculated with the arteriogram as the gold standard (83% and 96%, respectively, for normal vs abnormal, 87% and 99% for 50% stenosis, and 81% and 99% for occlusions). Color flow accurately identified the presence and extent of occlusions in 48 of 51 extremities (94%) when compared to arteriography plus operative findings, since arteriography alone tended to overestimate occlusion length. It is concluded that color flow Doppler alone may be used to screen patients with peripheral vascular disease to assess candidacy for endovascular procedures without antecedent arteriography, and that arteriography alone would exclude some patients from consideration by falsely overestimating occlusion lengths.

Angiography↗
PubMed1989

Differences in secretion of prostacyclin by venous and arterial endothelial cells grown in vitro in a static versus a mechanically active environment.

The objective of this study was to compare the effect of cyclic tension on prostacyclin secretion by venous and arterial endothelial cells. Early passage endothelial cells from bovine aortas and venae cavae were subjected to cyclic deformation (up to 17% elongation and 60 cycles/min). On posttreatment days 3 and 5 a radioimmunoassay was used to assess supernatant fluids from the endothelial cells for prostacyclin activity. The results indicate that in vitro (1) under static or control conditions, venous endothelial cells secrete significantly more prostacyclin (an increase of 1.5- and 4.8-fold on days 3 and 5, respectively) than do arterial endothelial cells isolated from the same animal and (2) prostacyclin secretion by mechanically deformed venous and arterial endothelial cells was significantly less than static control cultures on days 3 and 5. However, prostaglandin I2 secretion remained at higher levels in cyclically deformed venous endothelial cells than in cyclically deformed arterial endothelial cells. These data suggest that endothelial cells from the vena cava have a greater capacity for prostacyclin secretion than have their aortic counterparts. If these observations are maintained in vivo, greater prostacyclin secretion by venous endothelial cells could represent a homeostatic mechanism aimed at reducing thrombus formation in low-velocity areas of the vasculature.

Arteries↗
PubMed1989

Monocular blindness after penetrating trauma to the carotid artery.

Near-total or total blindness caused by chronic ocular ischemia is a well-recognized complication of severe atherosclerotic occlusive disease of the carotid artery (CA) but has not been previously reported in the English-language literature as a sequela of an occlusive CA injury. This report describes a patient who sustained a gunshot wound to the neck, which injured the ipsilateral internal CA, external CA, and vertebral artery. The location of the injuries precluded arterial repair. The patient was neurologically intact after operative exploration. Twenty months after the injury a marked loss of vision in the ipsilateral eye was detected. Chronic ocular ischemia was diagnosed from clinical findings and ophthalmoscopic examination results. Knowledge that chronic ocular ischemia and blindness can occur after an occlusive CA injury supports the use of primary arterial repair for all CA injuries. In those instances in which repair is not technically possible, frequent ophthalmoscopic examinations and testing of visual acuity should be used postoperatively to diagnose ocular ischemia; thus treatment to prevent the loss of sight can be carried out.

Adolescent↗
PubMed1988

The role of arterial reconstruction in penetrating carotid injuries.

The outcome of 80 patients with 85 penetrating injuries to the extracranial carotid artery (CA) were analyzed after three types of treatment: (1) 54 patients, 17 with a neurologic deficit, who underwent arterial reconstruction; (2) 18 patients, eight with a neurologic deficit, who had CA ligation or non-operative management of a CA occlusion; and (3) eight patients, two with a deficit, who had minimal nonocclusive injuries managed nonoperatively. Outcome was analyzed using a Carotid Neurologic Score (CNS). The CNS is a quantitative measure of neurologic outcome and survival and ranges from -1 to +3. The higher the CNS, the more favorable the outcome. The conditions of nine patients in group 1 neurologically improved after treatment, 41 were the same, and four were worse. Forty-four patients were neurologically intact and three died. The mean (+/- SD) CNS was 1.9 +/- 0.8. In group 2, one patient's condition improved, 13 stayed the same, and four deteriorated. Ten patients were intact and two died. The mean CNS was 1.3 +/- 1.13. In group 3, two patients' conditions improved and six stayed the same. All eight patients were intact; there were no deaths. The mean CNS was 2.3 +/- 0.35. There was a significantly higher CNS for groups 1 and 3 compared with group 2. The CNSs of groups 1 and 3 were not significantly different. Arterial reconstruction provides the best outcome for all penetrating CA injuries except nonocclusive limited intimal injuries that require only observation.

Adolescent↗
PubMed1988

Blunt popliteal artery trauma: one hundred consecutive injuries.

An institutional experience with 100 consecutive blunt popliteal artery injuries over a 20-year period was reviewed. The overall amputation rate was 15%; however, during the past 7 years this has declined from 23% to 6%. Minimizing delay in the revascularization of ischemic limbs, routine systemic heparinization, primary arterial repair when possible, repair of popliteal venous injuries, aggressive wound debridement, and early soft tissue coverage have contributed to improved limb salvage during the 1980s.

Adolescent↗
PubMed1988

Noninvasive determination of healing of major lower extremity amputation: the continued role of clinical judgment.

Various tests are used preoperatively to differentiate patients who require an above-knee amputation (AKA) from those whose vascular supply is adequate to heal a below-knee procedure (BKA). This 15-month study of 109 amputations compared four of these methods: segmental Doppler systolic pressure measurements, transcutaneous oxygen measurement (tcPO2), fluorescein angiography, and skin thermometry. There were 66 BKAs (85% healed primarily) and 43 AKAs (93% healed primarily). The actual level of amputation was determined by the operating surgeon without consideration of the preoperative test results, and the incidence of healing was then related to the test parameters. The average skin temperature at the amputation site was higher (93.7 degrees F) in the group that healed primarily compared with those who required operative stump revision (89.9 degrees F) (p less than 0.001). The mean midcalf tcPO2 was also higher in the BKA group that healed (PO2 = 36.6 mm Hg) compared with those who failed (PO2 = 16.4 mm Hg) (p less than 0.001). Qualitative skin fluorescence was less successful in differentiating success from failure. Of the 63 BKAs that fluorescein predicted would heal, eight failed (13%). Doppler pressures at the thigh, popliteal, midcalf, or ankle level were unreliable in predicting healing of a BKA. Formulation of indexes relating absolute pressures to the brachial systolic pressure did not improve the value of this examination. From this review it is concluded that the skin temperature and tcPO2 obtained at the site of proposed amputation were the most reliable prognostic noninvasive examinations.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1988

Differences in morphology, growth rate, and protein synthesis between cultured arterial and venous endothelial cells.

Intrinsic differences between aortic and venous endothelial cells were demonstrated by studies of morphology, growth rates, and protein synthesis. Endothelial cells from bovine thoracic aortas (AECs) and inferior vena caval (VECs) were harvested, maintained in cell culture, and characterized. VECs were consistently larger (mean cell diameter 14.3 micron vs 12.7 micron; p less than 0.001) and more pleomorphic than were AECs. Scanning electron microscopy revealed that VECs were thinner than AECs and that VECs had numerous fine, cellular processes that were much less abundant on the AECs. Enzymatic disaggregation of confluent cells resulted in a reduced generation time by the AECs compared with VECs. Moreover, VECs responded to disaggregation by a significantly larger increase in cell size than the AECs. Protein synthesis was quantitated by computer analysis of autoradiograph of two-dimensional gel eletrophoresis and separation of 998 35S-methionine-labeled proteins from cell lysates. Synthesis of 257 proteins was significantly different (p less than 0.05); synthesis of 239 proteins by VECs was either decreased (219) or undetectable (20) compared with those of AECs. In contrast, only 18 proteins were produced in significantly greater quantity by VECs than by AECs. The cytoskeletal proteins actin and alpha- and beta-tubulins were produced in significantly greater quantity by AECs than VECs. These results indicate that cultured endothelial cells of arterial origin are substantially different from those of the venous circulation. These phenotypic differences are maintained in vitro despite eliminating variability in hemodynamic stress and interaction with other cellular elements of the vessel wall.

Animals↗
PubMed1988

Chronic ocular ischemia and neovascular glaucoma: a result of extracranial carotid artery disease.

Severe occlusive disease of the carotid artery may produce a rare syndrome of chronic ocular ischemia. Prolonged retinal hypoxia is associated with characteristic funduscopic changes and neovascularization of the iris, with subsequent obstruction of aqueous humor resorption. A case of neovascular glaucoma as a result of severe bilateral carotid occlusive disease and the pathophysiology involved are discussed. Definitive treatment consisted of carotid endarterectomy and aggressive control of intraocular pressure, including operative placement of a drainage implant in the anterior chamber of the eye. Seizure activity and an exacerbation of glaucoma developed after successful revascularization, exemplifying the derangements in cerebral and ocular function that may result from chronic hypoperfusion.

Arterial Occlusive Diseases↗
PubMed1986

[Control of malaria--chemotherapy and immunoprophylaxis. 1. Chemotherapy].

A survey on the advances of the fight against malaria is given, and the present world-wide situation of this disease is described including the important role World Health Organization (WHO) is playing in this fight. The chapter on chemotherapy deals with recent progress in this field with special regard to mefloquine and quinghaosu, but other newer compounds are also discussed. The prospects of vaccination against malaria in general are considered, and the results of in vitro and in vivo experiments using antigens from sporozoites, asexual blood stages and gametocytes are reported. Humoral and cellular immunity and their part in the immune response of the infected host are evaluated as well as the progress in the continuous cultivation of the malaria parasites. Finally, the perspectives of the fight against malaria in the years to come are discussed.

Antimalarials↗