Biomedical subjects
PR Bell
Publications and source records attributed to PR Bell.
Vascular surgical society of great britain and ireland: impact of spontaneous embolization on cognitive function
BACKGROUND: Although microembolization may not be associated with focal neurological events following carotid endarterectomy (CEA), it might contribute towards cognitive impairment. METHODS: Forty-nine patients undergoing CEA underwent 30 min of preoperative ipsilateral transcranial Doppler (TCD) monitoring and a battery of tests of cognitive function, and the results were compared with those of age-matched normal controls. RESULTS: Seven patients who were spontaneously embolizing had significantly worse preoperative cognitive function scores than 42 patients with no recorded emboli (P = 0.03). Overall, patients undergoing CEA had a significant cognitive deficit compared with age-matched normal controls. CONCLUSION: Patients who have evidence of spontaneous preoperative embolization on TCD monitoring have a greater degree of preoperative cognitive impairment. This finding underlines the potential clinical importance of microembolization and suggests that this phenomenon should be investigated further.
Vascular surgical society of great britain and ireland: In situ replacement of infected aortic grafts with rifampicin-bonded prostheses
BACKGROUND: Prosthetic graft infection following abdominal aortic aneurysm (AAA) surgery is life threatening. Treatment options include total graft excision and extra-anatomic bypass or in situ replacement of the graft. The latter option is gaining popularity but the long-term outcome remains uncertain, particularly in light of the increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) infection. A retrospective study was undertaken to assess the outcome after graft excision and in situ replacement with a rifampicin-bonded prosthesis for the treatment of major aortic graft infection. The prevalence of MRSA and its influence on outcome was also assessed. METHODS: Over 6 years between January 1992 and December 1997, 11 patients (eight men) with major aortic graft infection underwent total graft excision and in situ replacement with a rifampicin-bonded prosthesis. RESULTS: The median age was 66 (range 49-78) years. Four patients presented with haemorrhage from an aortoenteric fistula, three had retroperitoneal abscess, two had graft occlusion, one had a perigraft collection on computed tomography and one presented with a ruptured suprarenal false aneurysm. Organisms were cultured from ten patients. Staphylococcus epidermidis and Streptococcus faecalis were predominant. MRSA was isolated from two patients, both of whom had originally undergone ruptured AAA repair. Two patients died and three suffered non-fatal complications. Two patients died during follow-up, one from suspected ongoing MRSA infection and the other from recurrent graft infection. Seven patients remain alive and clinically free from infection, although two were lost to follow-up at 12 and 15 months. CONCLUSION: The long-term results following total graft excision and in situ replacement with a rifampicin-bonded prosthesis appear to be favourable. MRSA infection seems to be associated with a poor prognosis.
Vascular surgical society of great britain and ireland: endovascular aortic aneurysm repair reduces mortality: a physiological analysis
BACKGROUND: Endovascular techniques are gaining acceptance as minimally invasive methods for abdominal aortic aneurysm repair, although there have been few studies that provide direct comparison with conventional techniques. A prospective study that compares morbidity and mortality rates following abdominal aortic aneurysm repair, using a physiological scoring system, is presented. METHODS: Between December 1994 and November 1997, 104 elective open aneurysm repairs and 49 endovascular aneurysm repairs were performed at this institution. These patient cohorts were compared using the Portsmouth predictor equation scoring system, which has been shown to predict outcome in vascular surgery. Prospective data from patient notes were used to obtain physiological and operative severity scores that were analysed to predict expected (E) to observed (O) mortality and morbidity rates. RESULTS: Although physiological variables were equivalent in both groups, conventional surgery had a higher mortality (P < 0.05) and morbidity (P < 0.001) rate than endovascular surgery, which was related to the operative severity scores. CONCLUSION: These data suggest that open aortic aneurysm repair has a higher operative severity than endovascular repair which may be reflected in increased mortality rates.
Vascular surgical society of great britain and ireland: role of superficial vein surgery in treatment of venous ulceration
BACKGROUND: Recent colour duplex studies of patients presenting with venous ulceration in the community have shown that between 55 and 60 per cent have isolated superficial venous insufficiency. Previous studies of the role of superficial surgery in the treatment of venous ulceration have applied postoperative compression bandaging and therefore it has not been possible to determine the role of superficial surgery in promoting ulcer healing. The purpose of this prospective study was, therefore, to examine the healing rate after superficial surgery in patients with isolated superficial venous incompetence and venous ulceration who did not undergo postoperative compression bandaging. METHODS: Patients with isolated superficial venous incompetence, as demonstrated by colour duplex scanning and an ankle : brachial pressure index greater than 0.8, underwent saphenofemoral or saphenopopliteal disconnection under local anaesthesia, or a high tie and strip under general anaesthesia. Compression bandaging was not applied after operation. Patients were followed regularly after surgery and the endpoint was ulcer healing. RESULTS: Between May 1994 and July 1997, 122 legs with venous ulceration and isolated superficial venous incompetence underwent superficial surgery. Ninety-three (76 per cent) had long saphenous incompetence alone, 13 (11 per cent) had short saphenous incompetence alone and 16 (13 per cent) had combined long and short saphenous incompetence. The median (range) patient age was 72 (28-94) years and the median duration of ulceration was 32 weeks (range 2 weeks to 32 years). The median (range) ulcer area was 9 (1-500) cm2. Ninety patients (74 per cent) had a local anaesthetic procedure while 32 (26 per cent) had general anaesthesia. Of patients who had long saphenous surgery, 69 had high ligation only and 24 had high ligation and strip. The healing rate by life-table analysis was 58 per cent at 6 months, 73 per cent at 1 year and 82 per cent at 18 months. Clinical review and colour duplex examination of patients with ulcers that had failed to heal (n = 18) showed that two had recurrent superficial to deep connections; the remainder had fixed ankle joints or severe osteoarthritis of the hip and knee. CONCLUSION: Superficial venous surgery in patients with isolated superficial venous incompetence and venous ulceration can achieve a very high healing rate in the absence of postoperative compression.
Vascular surgical society of great britain and ireland: angiogenesis and the atherosclerotic carotid plaque: association between symptomatology and plaque morphology
BACKGROUND: Symptomatic carotid disease due to thromboembolism has been associated with acute plaque instability and intraplaque haemorrhage. These features may be influenced by the fragility and position of plaque neovessels. The purpose of this study was, therefore, to determine whether any association existed between neovessel density, position, morphology and thromboembolic sequelae. METHODS: Carotid endarterectomy (CEA) samples were collected from 15 asymptomatic patients with greater than 80 per cent stenosis and from 13 patients with greater than 80 per cent stenosis and symptoms within 30 days of CEA. Groups were matched for sex, age, risk factors and plaque size. Samples were stained with haematoxylin and eosin, and Van Gieson stains. An endothelial-specific antibody to CD31 was used for immunohistochemistry. Plaques were assessed for histological characteristics while neovessels were counted and characterized by size, site and shape. RESULTS: There were more neovessels in plaques (P < 0.00001) and fibrous caps (P < 0.0001) from symptomatic than asymptomatic patients. Symptomatic plaque neovessels were larger in size (P < 0.004) and more irregular in shape. There was a significant increase in plaque necrosis and rupture in symptomatic plaques. Plaque haemorrhage and rupture were associated with more neovessels within the plaque (P < 0.02, P < 0. 001) and fibrous cap (P < 0.05, P < 0.004). Patients with preoperative or intraoperative embolization had more plaque and fibrous cap neovessels (P < 0.03, P < 0.001). CONCLUSION: Symptomatic carotid disease is associated with increased neovascularization within the atherosclerotic plaque and fibrous cap; these vessels appear larger in size, more irregular in shape and may contribute to plaque instability and onset of thromboembolic events.