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S Sheehan

Publications and source records attributed to S Sheehan.

At least 19 recordsLinked to original sources
PubMed2007

Abdominal aortic aneurysm repair and colonic infarction: a risk factor appraisal.

OBJECTIVE: Colonic infarction is a recognized complication of abdominal aortic aneurysm (AAA) surgery. The clinical difficulty in establishing the diagnosis combined with the patient's poor physiological status is usually associated with a fatal outcome. We assessed our experience with this problem to identify a possible risk factor profile for these patients. METHOD: Patients records were identified from the operative logs, intensive care unit, Hospital Inpatient Enquiry system and vascular unit databases over a 6-year period. RESULTS: A total of 405 patients underwent AAA repair during this period; 140 as emergency ruptures. Nine patients were identified from the databases with known colonic infarction (2.2%). One was a woman. The mean age was 70 years. Seven patients had emergency ruptures (5%). Twenty independent risk factors were analysed using univariate and multivariate logistic regression models. Significant risk factors identified by using a multivariate analysis included the nature of the presenting patient, preoperative hypotension, prolonged cross-clamp time, intra-operative ischaemia and postoperative acidosis. Confirmatory diagnosis was made by colonoscopy in eight patients. One patient survived following the salvage surgery. The mean duration of survival was 10.5 days. The overall mortality was 89% of patients. CONCLUSION: In our unit infrarenal AAA repair has a 2.2% rate of colonic infarction. A definitive diagnosis is best made by colonoscopy. A risk factor profile for the development of colonic infarction may be constructed on the basis of specific clinical parameters. Earlier intervention on the basis of this profile may ultimately reduce the current excessive mortality.

Aged↗
PubMed2004

Radiation-induced femoral arteritis.

Radiation arteritis is currently an uncommon sequalae of external beam radiation, however because of the increasing use of radiotherapy in the management of neoplastic conditions its recognition is increasingly important. We present two cases of debilitating femoral occlusive disease, secondary to radiation exposure, at a long period post irradiation and review the pathophysiolgy and management options for this condition.

Adult↗
PubMed2003

Evaluation of the impact of transthoracic endoscopic sympathectomy on patients with palmar hyperhydrosis.

OBJECTIVES: We assessed the impact of transthoracic endoscopic sympathectomy (TES) on the quality of life of patients with palmar hyperhydrosis. DESIGN: A retrospective questionnaire based study. METHODS: Patients undergoing TES at our institution between 1997 and 2002 received a SF-36 quality of life postal questionnaire. The pre- and post-operative symptoms were assessed. Statistical analysis was by means of the Student's t test. RESULTS: Ninety-four TES were carried out in 62 patients. Forty-one cases were female. The age range was 17-64 years. The mean follow-up period was 38.46 months. Mean hospital stay was 3 days. Compensatory hyperhydrosis was reported in 29 cases and only considered severe in four cases (9.7%). Forty-one patients replied to the questionnaire (66%). The overall quality of life (as assessed by the SF-36 form) was unanimously improved (p<0.0009) and demonstrated significant improvements in social functioning (p<0.0002), physical role limitations (p<0.0007), emotional well-being (p<0.0007) and overall energy levels (p<0.05). CONCLUSION: TES resulted in significant improvements inpatient's overall quality of life, social and emotional functioning. The procedure is associated with minimal morbidity and only a short inpatient stay is required. Patients should be cautioned on the possibility of compensatory hyperhydrosis which may occur in a small number of cases.

Adolescent↗
PubMed2003

Nontuberculous mycobacteria: incidence in Southwest Ireland from 1987 to 2000.

SETTING: The Southwest of Ireland (Counties Cork and Kerry) 1987-2000, average population 549,500. OBJECTIVE: Nontuberculous mycobacteria (NTM) cause significant morbidity worldwide and the study of epidemiology and characteristics helps in their prevention and treatment. This study was performed to determine the incidence of NTM disease in comparison to Mycobacterium tuberculosis (M. tuberculosis) and Mycobacterium bovis (M. bovis) in Southwest Ireland, over the above time period. DESIGN: A retrospective study was carried out in all human isolates of NTM, M. tuberculosis and M. bovis between 1987 and 2000, in the Southwest Region of Ireland. RESULTS: The mean incidence of NTM (0.4/100,000 population) has risen since 1995, principally of pulmonary Mycobacterium avium intracellulare complex (MAC). The annual incidence of M. tuberculosis in humans over 14 years in the same region was 971/100,000 population with a significant reduction since 1994 and M. bovis remained constant at 0.5/100,000 population. CONCLUSION: The increasing incidence of disease causing NTM noted in Southwest Ireland reflects global data and is surmised to be due to an ageing population, increased incidence related to chronic fibrotic lung disease, and environmental mycobacterial factors.

Adult↗
PubMed2000

The ligase chain reaction as a primary screening tool for the detection of culture positive tuberculosis.

BACKGROUND: The ligase chain reaction Mycobacterium tuberculosis assay uses ligase chain reaction technology to detect tuberculous DNA sequences in clinical specimens. A study was undertaken to determine its sensitivity and specificity as a primary screening tool for the detection of culture positive tuberculosis. METHODS: The study was conducted on 2420 clinical specimens (sputum, bronchoalveolar lavage fluid, pleural fluid, urine) submitted for primary screening for Mycobacterium tuberculosis to a regional medical microbiology laboratory. Specimens were tested in parallel with smear, ligase chain reaction, and culture. RESULTS: Thirty nine patients had specimens testing positive by the ligase chain reaction assay. Thirty two patients had newly diagnosed tuberculosis, one had a tuberculosis relapse, three had tuberculosis (on antituberculous therapy when tested), and three had healed tuberculosis. In the newly diagnosed group specimens were smear positive in 21 cases (66%), ligase chain reaction positive in 30 cases (94%), and culture positive in 32 cases (100%). Using a positive culture to diagnose active tuberculosis, the ligase chain reaction assay had a sensitivity of 93.9%, a specificity of 99.8%, a positive predictive value of 83.8%, and a negative predictive value of 99.9%. CONCLUSIONS: This study is the largest clinical trial to date to report the efficacy of the ligase chain reaction as a primary screening tool to detect Mycobacterium tuberculosis infection. The authors conclude that ligase chain reaction is a useful primary screening test for tuberculosis, offering speed and discrimination in the early stages of diagnosis and complementing traditional smear and culture techniques.

Adolescent↗
PubMed1998

Effects of human recombinant growth hormone (rhGH) on inflammatory responses in patients undergoing abdominal aortic aneurysm repair.

BACKGROUND: Human recombinant growth hormone (rhGH) has been shown to increase skeletal muscle protein synthesis and improve nitrogen balance in critically ill patients and those undergoing surgery. rhGH effects on hepatic protein turnover in critically ill patients are less clearly understood. OBJECTIVE: To examine rhGH effects on hepatic acute phase protein responses and inflammatory cytokine release in patients undergoing major surgery. DESIGN: Prospective double blind randomised trial. SETTING: Tertiary referral university teaching hospital. PATIENTS: Patients undergoing elective abdominal aortic aneurysm repair. INTERVENTION: Patients received rhGH (Genotropin, 0.3 IU/kg per day, n = 8) or placebo (n = 10) for 6 days prior to surgery. RESULTS: Blood levels of growth hormone (GH) and insulin-like growth factor (IGF-1) were measured following rhGH treatment and C-reactive protein (CRP), serum amyloid A (SAA) and the cytokines interleukin-6 (IL-6) and the IL-1 receptor antagonist (IL-1ra) were measured for up to 24 h following surgery. Significant increases in plasma rhGH (0.84 +/- 0.3, mean (sem) versus 52 +/- 20 mU/l, p < 0.0008) and IGF-1 levels (119 +/- 13 versus 644 +/- 110 ng/ml, p < 0.0001) were seen prior to surgery following rhGH administration. No differences in acute phase protein or cytokine levels were seen following surgery in patients receiving rhGH. CONCLUSIONS: These results indicate that pre-operative administration of rhGH does not alter acute phase protein or inflammatory cytokine release in response to major surgery.

Aged↗
PubMed1998

An "all comers" policy for ruptured abdominal aortic aneurysms: how can results be improved?

OBJECTIVE: To review our experience of a non-selective policy for the treatment of ruptured abdominal aortic aneurysm to see if the policy was justified, and to identify any preoperative risk factors that adversely influenced outcome. DESIGN: Retrospective study. SETTING: Teaching hospital, Republic of Ireland. SUBJECTS: 258 patients admitted with abdominal aortic aneurysms between January 1982 and December 1993. INTERVENTIONS: Definitive surgical treatment. MAIN OUTCOME MEASURES: Morbidity, mortality, and risk factors. RESULTS: In-hospital mortality for all patients was 43% (110/258). Overall, women did worse than men (28/44, 64%, died, compared with 96/214, 45%, p=0.03). The mortality among patients over the age of 80 (23/45, 51%) was not significantly different from that among younger patients (97/202, 48%). Blood pressure, platelet count, and haemoglobin concentration were all significantly lower preoperatively among those who died (p < 0.05). CONCLUSIONS: Age alone cannot be used to justify witholding definitive surgical treatment. Treatment should be aimed towards reversing haematological and haemodynamic abnormalities preoperatively to try to improve outcome.

Aged↗
PubMed1997

Immunological and physiological responses to aortic surgery: effect of reperfusion on neutrophil and monocyte activation and pulmonary function.

BACKGROUND: The aims of this study were to evaluate the effects of aortic clamping and unclamping on neutrophil and monocyte activation and release of plasma mediators in 20 patients undergoing elective aortic aneurysm surgery, and to correlate these findings with pulmonary haemodynamics and gas exchange. METHODS: Simultaneous arterial and mixed venous samples were obtained during and after aortic clamping and unclamping. RESULTS: Neutrophil respiratory burst activity in mixed venous samples increased significantly during the period of aortic clamping. An initial increase in neutrophil CD11b expression in venous blood 5 min after clamp removal was followed by a significant decrease in level of expression. Plasma tumour necrosis factor levels increased at the end of the cross-clamp period and reached a maximum 60 min following reperfusion. There was a significant and sustained rise in plasma thromboxane B2 levels following clamp removal. This increase correlated with the development of increased pulmonary vascular resistance. CONCLUSION: This study confirms the central role played by activated neutrophils in the early stages of reperfusion injury and also suggests a role for plasma mediators in mediating cardiopulmonary dysfunction during major vascular surgery.

Aged↗
PubMed1996

Glyceryl trinitrate prevents neutrophil activation but not thromboxane release following ischaemia-reperfusion injury.

The aim of this study was to determine whether glyceryl trinitrate (GTN) has a protective effect on neutrophil-mediated lung injury in a model of aortic occlusion (30 min) and reperfusion (120 min). Sprague-Dawley rats were randomized into control (n = 11), ischaemia-reperfusion (IR) (n = 12), and IR treated with GTN (2 micrograms kg-1 min-1) during reperfusion (n = 10). Myeloperoxidase (MPO) activity measured pulmonary neutrophil influx. Pulmonary endothelial permeability was measured by wet:dry weight ratio, bronchoalveolar lavage (BAL) protein and neutrophil counts. Neutrophil superoxide release was measured by flow cytometry in a further IR versus GTN experiment (n = 6 in each group). The significant increase in MPO activity produced by IR to a level of 7.99 units g-1 was prevented by GTN which reduced the level to 4.73 units g-1. The increase in pulmonary microvascular leakage after reperfusion was also prevented by GTN: BAL protein without GTN was 992 micrograms ml-1 and with GTN 579 micrograms ml-1; BAL neutrophil count without GTN was 3219 cells mm-3 and with GTN 820 cells mm-3; the wet:dry lung weight ratio without GTN was 3.8 and with GTN 3.3. Neutrophil superoxide release increased significantly after 40 min of reperfusion in the untreated IR group (P < 0.05). This increase was prevented in the GTN-treated group. GTN administration had no effect on plasma thromboxane production during revascularization. These data suggest that GTN administration during the reperfusion phase has the potential to decrease pulmonary microvascular injury.

Animals↗
PubMed1996

Tuberculosis due to Mycobacterium bovis in humans in the south-west region of Ireland: is there a relationship with infection prevalence in cattle?

OBJECTIVE: To compare the incidence of tuberculosis due to Mycobacterium bovis in humans to the prevalence of M. bovis infection in cattle in south-west Ireland and discuss possible links between them. SETTING: In the south-west region of Ireland, a mixed urban and rural community (pop. 536,000), there is a residuum of human tuberculosis caused by M. bovis. METHODS: A retrospective analysis of the incidence of culture-positive M. bovis disease in humans in south-west Ireland from 1983 to 1994 and of the results of tuberculin testing in cattle from 1978 to 1994 for the same region. RESULTS: One to five cases of human tuberculosis due to M. bovis were recorded per year while the overall prevalence of bovine infection fell gradually during the period of study from 467 tuberculin-positive animals per 100,000 cattle tested in 1983 to 158 per 100,000 in 1994. CONCLUSION: The low incidence plateau of human tuberculosis due to M. bovis together with the decline in prevalence of animal infection in the overall period studied suggest a cut-off in the animal to human chain of infection at two points; the animal source and the ingestion of (now pasteurized) milk. This would suggest that disease in humans is now due to reactivation of previous foci of infection which were acquired when milk pasteurization was not compulsory. Based on this, we would anticipate a further reduction and possible elimination of human tuberculosis due to M. bovis in this region in the next 10-15 years.

Animals↗
PubMed1995

Isolation of Mycobacterium chelonae in a bronchoscopy unit and its subsequent eradication.

SETTING: Contamination events with Mycobacterium chelonae in 7 patients undergoing bronchoscopy, out of a total of 100 patients in a 5-month period, were analysed. OBJECTIVE: To identify and assess the importance of factors thought to be relevant in the aetiology of these contamination events and by removing these factors, to eradicate the problem of continuing M. chelonae contamination. DESIGN: A retrospective analysis of the frequency of M. chelonae isolates from bronchoalveolar fluid, assessing the contribution of the following measures to the eradication of M. chelonae: (1) changes to the bronchoscopy unit's water supply; (2) insertion of bacterial filters; (3) installation of a new semi-automated cleaning machine incorporating an ultrasound cycle; (4) staff training in correct use of the new equipment. RESULTS: Following the discontinuation of using tapwater in the cleaning process, the above changes resulted in complete eradication of contamination events, with no further events occurring in the following 12 months. CONCLUSION: Insertion of bacterial filters into the water supply, with the addition of a more sophisticated semi-automatic cleaning machine involving an ultrasound cycle in addition to conventional cleaning methods currently used, will help reduce or eradicate contamination events with M. chelonae in bronchoscopy units.

Adult↗
PubMed1992

Morphological changes and alterations in regional intrarenal blood flow induced by graded renal ischemia.

A model of renal ischemia was used to study morphological changes and alterations in intrarenal blood flow. Renal artery blood flow was reduced from 120 to 20 ml./minute (normal 172 +/- 14) for 3 weeks. Morphological changes were assessed histologically, and by electronmicroscopy. Intrarenal blood flow was determined using microspheres. Flow rates less than 80 ml./minute resulted in a progressive loss of renal volume with arterial thrombosis and renal infarction at 20 ml./minute. Histological changes included loss of glomerular volume, tubular dilatation (60 ml./minute), tubular cast formation (50 ml./minute) tubular atrophy, interstitial fibrosis, arteriolar thickening (40 ml./minute) and glomerular hyalinization (30 ml./minute). Electronmicroscopy changes at 60 ml./minute (loss of glomerular microvasculature, unfolding of glomerular vascular tuft, appearance of blind ending vessels) progressed to disruption of glomerular architecture noted at 30 ml./minute. Narrowing of medullary blood vessels (60 ml./minute) and neovascularisation (40 ml./minute) was observed. Progressive ischemia decreased medullary, inner cortical and outer cortical blood flow (5.9 to 2.1 ml./minute/gm.) p less than 0.01, with a compensatory increase to the opposite kidney.

Animals↗