Biomedical subjects

M S Baguneid

Publications and source records attributed to M S Baguneid.

8 recordsLinked to original sources

PubMed2006

Tissue engineering of blood vessels.

BACKGROUND: Tissue engineering techniques have been employed successfully in the management of wounds, burns and cartilage repair. Current prosthetic alternatives to autologous vascular bypass grafts remain poor in terms of patency and infection risk. Growing biological blood vessels has been proposed as an alternative. METHODS: This review is based on a literature search using Medline, PubMed, ISIS and CAS of original articles and reviews, and unpublished material and abstracts. RESULTS AND CONCLUSIONS: Complete incorporation into host tissues and the maintenance of a viable and self-renewing endothelial layer are the fundamental goals to be achieved when developing a tissue-engineered blood vessel. Sourcing of cells and modulating their interaction with extracellular matrix and supporting scaffold have been the focus of intense research. Although the use of tissue-engineered blood vessels in humans is so far limited, advances in our knowledge of stem cell precursors and the development of new biomaterials should enable this technology to reach routine clinical practice within a decade.

Biotechnology↗

PubMed2004

Routine measurement of radioisotope left ventricular ejection fraction prior to vascular surgery: is it worthwhile?

OBJECTIVE: To determine whether estimation of left ventricular (LV) ejection fraction (EF) by means of multiple gated acquisition (MUGA) scanning could reliably stratify cardiac risk prior to elective major vascular surgery. METHODS: A review of the English-language literature. RESULTS AND CONCLUSIONS: Twenty-two studies enrolling a total of 3096 patients were identified from 1984 to date. Selection bias, blinding of the results, different cut-off limits, and several retrospective studies were some of the problems preventing a comprehensive analysis. The resting LVEF was not found to be a consistent predictor of perioperative ischaemic cardiac events. In the perioperative phase, poor LV function was, mainly, predictive of congestive heart failure, and, in the long-term, of cardiac outcome. The presence of myocardial wall motion abnormalities was also associated with both a higher chance of postoperative cardiac complications and a worse long-term cardiac outcome. Although measurements of LV function seem to play a key role in defining a patient's long-term prognosis, the value of routinely measuring LVEF preoperatively is limited and, therefore, MUGA scanning cannot be recommended as a general screening test. Despite this, it has been widely used for cardiac risk assessment in vascular surgery, and only recently its popularity has started declining. Other tests, such as stress-echocardiography and myocardial perfusion imaging, used selectively in moderate-risk patients can refine prediction of cardiac risk. In the future, gated stress myocardial perfusion scintigraphy, perhaps combined with ANP/BNP plasma level determination, may become a first choice test in preoperative cardiac risk assessment.

Gated Blood-Pool Imaging↗

PubMed2001

Outcome of transaxillary rib resection for thoracic outlet syndrome--a 10 year experience.

BACKGROUND: This study assessed the outcome of transaxillary first and/or cervical rib resection in a unit, which has a policy of combined assessment by a neurologist and vascular surgeon. METHODS: 61 patients underwent 83 transaxillary rib resections for thoracic outlet syndrome. A retrospective case note review of these patients was undertaken. All patients completed a telephone questionnaire regarding long-term outcome. RESULTS: Post-operative outpatient assessment at a median of 6 months recorded 91.5% improved, of whom 61.5% were symptom-free. 61% were available for the telephone questionnaire at a median follow-up of 4 yr. 74% reported an improvement, with complete resolution in 58%. Six described temporary improvement following surgery. CONCLUSION: Transaxillary rib resection is a safe and effective procedure, allowing almost two thirds of patients a return to normal activity. Combined assessment by vascular and neurological teams may help in patient selection for surgery, as well as the accurate long-term assessment of outcome.

Adolescent↗

PubMed2001

A comparison of para-anastomotic compliance profiles after vascular anastomosis: nonpenetrating clips versus standard sutures.

PURPOSE: Anastomotic compliance is an important predictive factor for long-term patency of small diameter vascular reconstruction. In this experimental study we compare the compliance of continuous and interrupted sutured vascular anastomoses with those using nonpenetrating clips. METHODS: Both common carotid arteries in nine goats (average weight, 57 +/- 5.7 kg) were transected, and end-to-end anastomoses were constructed with nonpenetrating clips or polypropylene sutures. The latter were applied with both interrupted and continuous techniques. Intraluminal pressure was measured with a Millar Mikro-tip transducer, and vessel wall motion was determined with duplex ultrasound equipped with an echo-locked wall-tracking system. Diametrical compliance was determined. Environmental scanning electron microscopy was performed on explanted anastomoses. RESULTS: There was a reduction in anastomotic compliance and associated proximal and distal para-anastomotic hypercompliant zones with the use of all techniques. However, compliance loss was significantly less in those anastomoses with clips and interrupted sutures when compared with continuous suture (P <.001). Furthermore, the total compliance mismatch across anastomoses with continuous sutures was significantly greater than those with clips or interrupted sutures (P <.05). The mean time for constructing clipped anastomoses was 5.7 +/- 1.4 minutes, which was significantly less than either continuous (P <.0001) or interrupted sutures (P <.0001). Furthermore, environmental scanning electron microscopy demonstrated minimal intimal damage with good intimal apposition in the clip group. CONCLUSION: Anastomoses performed with nonpenetrating clips resulted in improved para-anastomotic compliance profiles and reduced intimal damage when compared with those with polypropylene sutures. These benefits may enhance long-term graft patency by reducing the risk of anastomotic intimal hyperplasia.

Anastomosis, Surgical↗

PubMed2001

A randomized study to evaluate the effect of a perioperative infusion of dopexamine on colonic mucosal ischemia after aortic surgery.

PURPOSE: Colonic ischemia after aortic surgery is associated with increased mortality and morbidity rates. This study was conducted as a single-center side arm to a multicenter, randomized, placebo-controlled study to evaluate the effect of dopexamine hydrochloride on its incidence. METHODS: Thirty patients, mean age 65.1 years (range, 46-84), undergoing elective infrarenal aortic surgery were entered. Preoperative hemodynamic and respiratory parameters were optimized. Patients were then randomly assigned to receive a perioperative infusion of dopexamine at 2 microg/kg per minute (n = 12) or 0.9% saline placebo (n = 18). All patients underwent colonoscopy and biopsy preoperatively and 1 week postoperatively. Specimens were assessed for evidence of mucosal ischemia, presence of mast cell tryptase, myeloperoxidase activity, and both the inducible and endothelial isoforms of nitric oxide synthase. RESULTS: There was no significant difference in perioperative fluid and blood requirements or hemodynamic and respiratory parameters between the two groups. However, there was significantly less evidence of mucosal ischemic changes in dopexamine-treated patients (n = 1) compared with placebo (n = 8) (P =.049). Furthermore, when preoperative biopsies were compared with those performed 1 week postoperatively, nine (50%) patients in the placebo group and two (16.7%) in the dopexamine group scored worse. Although there was no significant difference in inflammatory markers between the two groups, both mast cell tryptase and myeloperoxidase expression were increased in patients with histologic evidence of ischemia (P <.05). Furthermore, inducible nitric oxide synthase staining within the vascular (P =.001) and lamina propria (P <.05) components of the mucosa was also significantly greater. CONCLUSION: A perioperative dopexamine infusion affords significant histologic protection to colonic mucosa after aortic surgery.

Adult↗

PubMed1999

Cardiovascular surgery in the elderly.

Throughout the developed world, the population is aging at an alarming rate. This has become an issue of great concern. The growing number of elderly people within the community has several health and economic implications. The prevalence of atherosclerosis increases with age and directly impacts on the workload of both cardiac and vascular surgeons. The decision to operate should not be based on age alone but reflect an assessment of the risk benefit ratio of individual cases. Increased life expectancy, safer anaesthesia and less invasive surgical techniques have led to more patients being considered for surgical intervention. However, this will inevitably result in an overwhelming burden on national health resources, a factor that may force some practitioners to deny treatment on the grounds of chronological and not biological age.

Age Factors↗

PubMed1998

Histological study of colonic ischaemia after aortic surgery.

BACKGROUND: Colonic ischaemia is a well documented complication of abdominal aortic reconstruction. In this prospective study patients had routine preoperative and postoperative colonoscopy and biopsy, in order to determine the true incidence and implications. METHODS: Fifty-six patients undergoing elective infrarenal aortic surgery, 28 for aneurysm and 28 for occlusive disease, had colonoscopy and biopsy before and 1 week after operation. RESULTS: Colonic ischaemia was identified histologically in biopsies from 16 (30 per cent) of 53 patients. Almost half the patients had normal macroscopic appearances. Two factors exhibited a statistically significant association with the development of ischaemia: prolonged cross-clamp time (P < 0.05) and postoperative diarrhoea (P< 0.001). Co-morbidity was much higher in patients with colonic ischaemia (P< 0.005). Overall morbidity was significantly greater in the aneurysm group (P < 0.05). CONCLUSION: Colonic ischaemia is common after aortic reconstruction. When suspected, colonoscopy with biopsy is diagnostic.

Aged↗

PubMed1997

Carpal tunnel decompression under local anaesthetic and tourniquet control.

A postal survey within the North West Region (UK) revealed that 66% of the consultant orthopaedic surgeons did not use local anaesthesia routinely for carpal tunnel decompression. This prospective study was set up to assess the effectiveness, safety and patient tolerance of performing this procedure using local anaesthesia and upper arm tourniquet control. Eight-six carpal tunnel decompressions were performed on 75 consecutive and unselected patients with confirmed carpal tunnel syndrome over a 6-month period. Completed questionnaires were obtained before discharge. None or only slight discomfort was experienced for all aspects of the operation in at least 94%. None of the patients reported severe and unbearable discomfort. At review, 3 months postoperatively, all patients with the exception of two reported complete resolution of preoperative symptoms. The use of local anaesthesia and a tourniquet is safe, effective and well-tolerated in carpal tunnel decompressions.

Adult↗