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W O'Neill

Publications and source records attributed to W O'Neill.

At least 19 recordsLinked to original sources
PubMed2003

ABC chromogenic agar: a cost-effective alternative to standard enteric media for Salmonella spp. isolation from routine stool samples.

Salmonellosis is the second most common cause of bacterial gastroenteritis, yet the yield from routine stool culture is low. Commonly used selective enteric media have poor specificities for salmonella identification, resulting in a high laboratory workload. A special chromogenic medium, ABC agar, is a promising alternative but its cost-effectiveness has not been evaluated in diagnostic laboratories. A collaborative study is therefore undertaken in two district general hospitals laboratories. Routine stool samples (n=866) were subcultured onto ABC agar half plates after selective enrichment in selenite broth. Similarly, 246 and 620 stool samples were subcultured onto desoxycholate lactose sucrose (DCLS) and xylose lactose desoxycholate (XLD) whole agar plates, respectively. Salmonella spp. were isolated from only 14 (1.6%) of stool samples tested. Specificity was significantly higher for ABC (98%) than DCLS (67%) or XLD (78%) agars. Welcan workload units (ABC 4.8, XLD and DCLS both 7.3) and costs per specimen (ABC 1.26 pounds sterling, DCLS 3.81 pounds sterling and XLD 1.83 pounds sterling) were similarly lower with ABC agar. The results indicate that ABC chromogenic agar offers improvements in specificity, workload and costs over conventional enteric media for Salmonella spp. isolation.

Agar↗
PubMed2003

Coronary stenting versus coronary bypass surgery in patients with multiple vessel disease and significant proximal LAD stenosis: results from the ERACI II study.

PURPOSE: To compare percutaneous coronary intervention (PCI) using stent implantation versus coronary artery bypass graft (CABG) in patients with multiple vessel disease with involvement of the proximal left anterior descending coronary artery (LAD). METHODS: 230 patients with multiple vessel disease and severe stenosis of the proximal LAD (113 with PCI, 117 with CABG). They were a cohort of patients from the randomised ERACI (Argentine randomized trial of percutaneous transluminal coronary angioplasty versus coronary artery bypass surgery in multivessel disease) II study. RESULTS: Both groups had similar baseline characteristics. There were no significant differences in 30 day major adverse cardiac events (death, myocardial infarction, stroke, and repeat procedures) between the strategies (PCI 2.7% v CABG 7.6%, p = 0.18). There were no significant differences in survival (PCI 96.4% v CABG 95%, p = 0.98) and survival with freedom from myocardial infarction (PCI 92% v CABG 89%, p = 0.94) at 41.5 (6) months' follow up. However, freedom from new revascularisation procedures (CABG 96.6% v PCI 73%, p = 0.0002) and frequency of angina (CABG 9.4% v PCI 22%, p = 0.025) were superior in the CABG group. CONCLUSION: Patients with multivessel disease and significant disease of the proximal LAD randomly assigned in the ERACI II trial to PCI or CABG had similar survival and survival with freedom from myocardial infarction at long term follow up. Repeat revascularisation procedures were higher in the PCI group.

Aged↗
PubMed2003

Detection of juvenile sleep deprivation by stochastic optimization of pupillographic records.

OBJECTIVE: To address the challenging problem of measuring juvenile sleep deprivation, we test the hypothesis that a pupillographic method found successful for adult narcoleptics might also discriminate between sleep deprived juveniles acting as their own controls. METHODS: A linear, nonstationary model relating pupillary diameter and a random photic stimulus are estimated by recursive regressions from pupillographic records of 8 juveniles of median age 7 years acting as their own rested controls. The estimated pupillary impulse response noise functions are stochastically optimized using the Kullback divergence measure to maximally separate the sleep deprived records from the control records. RESULTS: Both the average and covariance statistics of the estimated pupillary noise functions exhibit statistically significant differences between sleep deprived and rested subjects. The main result is that sleep deprivation decreases pupillary noise variance; a finding consistent with a previous study of adult narcoleptics. Further, it was found that virtually the same stochastic parameters were optimal for the juvenile sleep deprived data and for the previous adult narcoleptic study. CONCLUSIONS: Although our results are preliminary, the consistent reduction of pupillary noise appears to justify a comprehensive clinical trial across a broad range of age classes. In addition, the finding that the same parameters stochastically optimize both juvenile and adult recordings suggests the procedure holds promise as a clinical test which could produce sleep deprivation measures simultaneous with data collection.

Algorithms↗
PubMed2002

Immunological and haematinic consequences of feeding a standardised Echinacea (Echinacea angustifolia) extract to healthy horses.

This study was undertaken to compile new data on the efficacy of Echinacea in stimulating the immune system of the horse. Use of Echinacea is becoming widespread in horses, despite an absence of controlled laboratory research into its effectiveness or safety. This paper documents results of a double-blind, placebo-controlled, cross-over trial investigating the effect of standardised Echinacea extract on 8 horses. Animals were supplemented with Echinacea or placebo for 42 days, and their response to supplements recorded. Treatment with Echinacea increased phagocytic ability of isolated neutrophils, boosted peripheral lymphocyte counts and appeared to stimulate neutrophil migration from peripheral circulation into the tissues. Echinacea supplement also increased the size and concentration of peripheral red blood cells, and the concentration of haemoglobin and packed cell volume. It was concluded that Echinacea effectively stimulates equine immunocompetence, and the plant extract behaves, in equine subjects, as a haematinic agent, i.e. one which improves the quality of blood by increasing haemoglobin levels and the number of erythrocytes and which, by virtue of their effects on oxygen transport cells, are considered to improve parameters of exercise physiology and performance.

Adjuvants, Immunologic↗
PubMed2001

Argentine Randomized Study: Coronary Angioplasty with Stenting versus Coronary Bypass Surgery in patients with Multiple-Vessel Disease (ERACI II): 30-day and one-year follow-up results. ERACI II Investigators.

OBJECTIVE: The purpose of this study was to compare percutaneous transluminal coronary revascularization (PTCR) employing stent implantation to conventional coronary artery bypass graft surgery (CABG) in symptomatic patients with multivessel coronary artery disease. BACKGROUND: Previous randomized studies comparing balloon angioplasty versus CABG have demonstrated equivalent safety results. However, CABG was associated with significantly fewer repeat revascularization procedures. METHODS: A total of 2,759 patients with coronary artery disease were screened at seven clinical sites, and 450 patients were randomly assigned to undergo either PTCR (225 patients) or CABG (225 patients). Only patients with multivessel disease and indication for revascularization were enrolled. RESULTS: Both groups had similar clinical demographics: unstable angina in 92%; 38% were older than 65 years, and 23% had a history of peripheral vascular disease. During the first 30 days, PTCR patients had lower major adverse events (death, myocardial infarction, repeat revascularization procedures and stroke) compared with CABG patients (3.6% vs. 12.3%, p = 0.002). Death occurred in 0.9% of PTCR patients versus 5.7% in CABG patients, p < 0.013, and Q myocardial infarction (MI) occurred in 0.9% PTCR versus 5.7% of CABG patients, p < 0.013. At follow-up (mean 18.5 +/- 6.4 months), survival was 96.9% in PTCR versus 92.5% in CABG, p < 0.017. Freedom from MI was also better in PTCR compared to CABG patients (97.7% vs. 93.4%, p < 0.017). Requirements for new revascularization procedures were higher in PTCR than in CABG patients (16.8% vs. 4.8%, p < 0.002). CONCLUSIONS: In this selected high-risk group of patients with multivessel disease, PTCR with stent implantation showed better survival and freedom from MI than did conventional surgery. Repeat revascularization procedures were higher in the PTCR group.

Aged↗
PubMed2001

Stenting to reverse left ventricular ischemia due to left main coronary artery compression in primary pulmonary hypertension.

Angina is a common symptom of severe pulmonary hypertension. Although many theories for the source of this pain have been proposed, right ventricular ischemia is the one most commonly accepted as the cause. We report on two patients with primary pulmonary hypertension who had angina with normal activity or on provocation. One patient had severe left ventricular dysfunction. Both were found to have severe ostial stenosis of the left main coronary artery as a result of compression from a dilated pulmonary artery. Both patients underwent stenting of the left main coronary artery with excellent angiographic results, and complete resolution of the signs and symptoms of angina and left ventricular ischemia. Left ventricular ischemia due to compression of the left main coronary artery may be a much more common mechanism of angina and left ventricular dysfunction in patients with pulmonary hypertension than previously acknowledged. Stenting of the coronary artery can be done safely with the resolution of these symptoms.

Aged↗
PubMed2001

One-year follow-up after primary coronary intervention for acute myocardial infarction in diabetic patients. A substudy of the STENT PAMI trial.

OBJECTIVE: This analysis was undertaken to determine the composite incidence of cumulative adverse events (death, reinfarction, disabling stroke, and target vessel revascularization) at the end of the first year after acute myocardial infarction, in diabetic patients who underwent coronary stenting or primary coronary balloon angioplasty. METHODS: From the STENT PAMI trial, we analyzed the 6-month angiographic and 1-year clinical outcomes of 135 diabetic (112, noninsulin dependent) patients who underwent the randomization process of the trial and compared them with 758 nondiabetic patients. RESULTS: Coronary stenting did not significantly reduce the primary composite clinical end point when compared with PTCA (20 vs. 30%, p=0.2). A significant benefit from stenting was observed in patients with noninsulin dependent diabetes, with a trend toward a lesser need for new revascularization procedures (10 vs. 21%, p<.001), with a significant reduction in the primary composite clinical end point at 1 year (12 vs. 28%, p=. 04). At 6 months, the restenosis rate were significantly reduced only in nondiabetic patients (18 vs. 33%, p<. 001). Diabetic patients had the same restenosis rate (38%) either with stenting or balloon PTCA. CONCLUSIONS: Coronary Stenting in diabetics noninsulin dependent offered a significant reduction in the composite incidence of major clinical adverse events compared with balloon PTCA.

Angioplasty, Balloon, Coronary↗
PubMed2000

Rotational atherectomy or balloon angioplasty in the treatment of intra-stent restenosis: BARASTER multicenter registry.

The BARASTER registry was formed to evaluate the initial success and long-term results of rotational atherectomy in the management of in-stent restenosis. Rotational atherectomy was used in 197 cases of in-stent restenosis: 46 with stand-alone rotational atherectomy or at most 1 atmosphere of balloon inflation (Rota strategy), and 151 with rotational atherectomy and adjunctive balloon angioplasty <1 atmosphere (Combination strategy). These were compared with 107 episodes of in-stent restenosis treated with balloon angioplasty alone. In this observational study, the use of Combination therapy was associated with a slightly higher initial success rate (95% vs. 87% with the Rota strategy and 89% with Balloons, P = 0.08). There was a reduction in one year clinical outcomes (death, myocardial infarction or target lesion revascularization) in the combination group (38% vs. 60% with Rota and 52% with balloons, P = 0.02). These data support a benefit of the strategy of debulking with rotational atherectomy followed by adjunctive balloon angioplasty, in the management of in-stent restenosis.

Aged↗
PubMed2000

Cervical cancer screening in Ireland.

Screening for cervical cancer commenced in Ireland on an opportunistic basis in the late 1960s. The Data Protection Act was recently amended to allow access to specific databases for the purpose of setting up an age sex register for breast and cervical cancer screening. A pilot cervical screening programme is planned for women aged 25-60 years living in the Mid Western Area Health Board region.

Adult↗
PubMed2000

A comparative analysis of primary stenting and optimal balloon coronary angioplasty in acute myocardial infarction. Six month results from the STENT PAMI trial.

OBJECTIVE: To compare the outcome of balloon PTCA with final coronary stenosis diameter (SD) < or =30 %, with elective coronary stenting. METHODS: We performed a comparative analysis of the 6 month outcomes in patients treated with primary stenting and those who obtained an optimal balloon PTCA result treated during the first 12 hours of AMI onset included in the STENT PAMI randomized trial. RESULTS: The results were analysed into 3 groups: primary stenting (441 patients, SD=22+/-6 %), optimal PTCA (245 patients), and non-optimal PTCA (182 patients, SD= 37+/-5 %). At the end of the 6 months primary stent group presented with the lowest restenosis(23 vs. 31 vs. 45 %, p=0.001, respectively). Ischemia-driven target vessel revascularization rate (TVR) (7 vs. 15.5 vs. 19 %, p=0.001, respectively). CONCLUSION: At the 6 month follow-up, primary stenting offered the lowest restenosis and ischemia-driven TVR rates. Compared to optimal balloon PTCA. Non-optimal primary balloon PTCA pts (SD=31-50 %), had the worst late angiographic outcomes and should be treated more actively with coronary stent implantation.

Angioplasty, Balloon, Coronary↗
PubMed1998

Safety and cost-effectiveness of early discharge after primary angioplasty in low risk patients with acute myocardial infarction. PAMI-II Investigators. Primary Angioplasty in Myocardial Infarction.

OBJECTIVES: The second Primary Angioplasty in Myocardial Infarction (PAMI-II) study evaluated the hypothesis that primary percutaneous transluminal coronary angioplasty (PTCA), with subsequent discharge from the hospital 3 days later, is safe and cost-effective in low risk patients. BACKGROUND: In low risk patients with myocardial infarction (MI), few data exist regarding the need for intensive care and noninvasive testing or the appropriate length of hospital stay. METHODS: Patients with acute MI underwent emergency catheterization with primary PTCA when appropriate. Low risk patients (age <70 years, left ventricular ejection fraction >45%, one- or two-vessel disease, successful PTCA, no persistent arrhythmias) were randomized to receive accelerated care (admission to a nonintensive care unit and day 3 hospital discharge without noninvasive testing [n = 237] or traditional care [n = 234]). RESULTS: Patients who received accelerated care had similar in-hospital outcomes but were discharged 3 days earlier (4.2+/-2.3 vs. 7.1+/-4.7 days, p = 0.0001) and had lower hospital costs ($9,658+/-5,287 vs. $11,604+/-6,125 p = 0.002) than the patients who received traditional care. At 6 months, accelerated and traditional care groups had a similar rate of mortality (0.8% vs. 0.4%, p = 1.00), unstable ischemia (10.1% vs. 12.0%, p = 0.52), reinfarction (0.8% vs. 0.4%, p = 1.00), stroke (0.4% vs. 2.6%, p = 0.07), congestive heart failure (4.6% vs. 4.3%, p = 0.85) or their combined occurrence (15.2% vs. 17.5%, p = 0.49). The study was designed to detect a 10% difference in event rates; at 6 months, only a 2.3% difference was measured between groups, indicating an actual power of 0.19. CONCLUSIONS: Early identification of low risk patients with MI allowed safe omission of the intensive care phase and noninvasive testing, and a day 3 hospital discharge strategy, resulting in substantial cost savings.

Aged↗
PubMed1997

Predictors of acute and long-term outcome with transluminal extraction atherectomy: the New Approaches to Coronary Intervention (NACI) registry.

The New Approaches to Coronary Intervention (NACI) registry was established to define the role of new coronary devices in overcoming the limitations of balloon angioplasty. The purpose of the present study was to evaluate the acute and long-term efficacy of the transluminal extraction catheter (TEC) device utilizing data from the NACI registry and identify clinical and anatomic patient subsets who may benefit from this device. From 1990-1994, >4,300 patients from 39 clinical sites enrolled consecutive patients treated with one of the 7 new devices to the NACI registry. The study population consists of 331 patients (385 lesions) treated with planned TEC as the sole new device. Of these patients, 243 (292 lesions) were treated for saphenous vein graft (SVG) disease and 88 (93 lesions) for native disease. Patients undergoing SVG treatment were older and more likely to be male. They had lower ventricular function, more unstable angina, and a higher incidence of congestive heart failure. Multivessel disease was more prevalent in the SVG cohort, as was evidence of thrombus before treatment. Although device success was achieved in 50% of SVG lesions and 41% of native lesions, lesion success was achieved in 90% and 78%, respectively, after adjunctive balloon angioplasty, and procedure success rates were 86% and 79%, respectively. The in-hospital major complication (death/Q-wave myocardial infarction/emergency coronary artery bypass graft [CABG] surgery) rate was higher in the SVG cohort (6.2% vs 2.3%), mainly due to higher mortality rate (5.3% vs 1.1%). Multivariate analysis showed that SVG was not an independent predictor for either an in-hospital major complication or clinical failure. The risk factors for major in-hospital complications were history of congestive heart failure (odds ratio = 3.17) and thrombus (odds ratio = 3.36). For clinical failure the risk factors were diabetes (odds ratio = 1.88), thrombus (odds ratio = 2.08), and calcium (odds ratio = 3.09). One-year rates of death, Q-wave myocardial infarction, or any repeat revascularization were 51% in the SVG cohort and 41% in the native cohort. Following adjustment, patients treated for SVG disease did not have a higher risk when compared with those treated for native disease. The factors significantly associated with this composite event at 1 year are male (relative risk = 1.41), patients with history of congestive heart failure (relative risk = 1.56), and total occlusions (relative risk = 1.52). This study shows that for both SVG and native cohorts, device success rates were low with TEC alone, but acceptable lesion success rates were achieved when adjunctive PTCA was used. In-hospital as well as 1-year major complications were higher in the SVG cohort. However, after adjusting for other risk factors, SVG attempt was not significantly associated with either in-hospital or 1-year events.

Aged↗
PubMed1997

Timing of coronary artery bypass grafting after acute myocardial infarction.

Appropriate timing for coronary artery bypass grafting (CABG) after acute myocardial infarction (AMI) remains controversial. We retrospectively examined 423 patients who underwent CABG within 21 days of an AMI between 1992 and 1995, mainly for postinfarction angina and complex anatomy. The operative mortality rates associated with increasing time intervals between AMI and CABG were 17.4, 9.1, 4.0, and 5.8 per cent, for less than 6 hours, 6 to 24 hours, 1 to 7 days, and 7 to 21 days, respectively. There were 25 (5.9%) deaths overall. Statistical analysis was performed to evaluate the following preoperative parameters: age, sex, reoperation, previous myocardial infarction (MI), MI type and location, anatomy, cardiogenic shock, unstable angina, ventricular arrhythmias, extending MI, ejection fraction, indications for surgery, cardiac index, and interval from infarction to CABG. Interval between operation and AMI did not have a significant impact on patient outcome. Factors associated with an increased hospital mortality were ejection fraction < 30 per cent, age > 70 years, presence of cardiogenic shock, and cardiac index < 1.5. Only cardiac index proved to be a significant predictor of mortality (P < 0.001). We conclude that the timing of CABG, in and of itself, has no significant effect on hospital mortality of symptomatic patients within 3 weeks of AMI.

Age Factors↗
PubMed1996

A study of laser-based removal of polymethylmethacrylate bone cement.

Complications are often produced with the removal of bone cement from the femoral cavity in the treatment of a failed hip prosthesis. Apart from being slow and difficult the conventional process runs the risk of producing damage to the femur. Ultrasonic techniques have been suggested to achieve these ends but removal of the cement by this approach is not entirely easy. The alternative laser-based approach would seem to have significant advantages over conventional techniques. The laser is capable of delivering energy to a specific region or surface under close control. The choice of laser is determined by its ability to ablate the cement and the ease with which it can be delivered to the base of the femur cavity. This paper examines several laser wavelengths: CO2 (10.6 microns), excimer (248 nm), Hol:YAG (2.12 microns), and presents polymethylmethacrylate (PMMA) vaporization thresholds for each laser.

Absorption↗
PubMed1995

Rapid hemodynamic improvement after reperfusion during right ventricular infarction.

OBJECTIVES: This study sought to determine the effects of reperfusion on hemodynamic status and hospital course in patients with right ventricular infarction. BACKGROUND: In contrast to the relatively low risk associated with acute inferior myocardial infarction, right ventricular infarction is associated with higher in-hospital morbidity and mortality. However, the potential benefits of reperfusion in patients with right ventricular infarction are unknown. Consequently, this study evaluated the potential benefits of primary angioplasty in patients with right ventricular infarction. METHODS: Of 141 consecutive patients admitted to the hospital for inferior myocardial infarction, 27 were identified as having right ventricular involvement by electrocardiographic and hemodynamic criteria. Seventeen patients achieved patency of the infarct-related right coronary artery by primary coronary angioplasty within 24 h of hospital admission, but 10 patients did not. All patients had invasive hemodynamic monitoring at the time of hospital admission, and subsequent serial hemodynamic status and clinical events were recorded. RESULTS: Patients with successful reperfusion demonstrated improved right atrial pressure, pulmonary capillary wedge pressure and right atrial/pulmonary capillary wedge pressure ratio as early as 8 h after reperfusion, whereas patients without reperfusion had no hemodynamic improvement over 24 h. Right atrial pressure demonstrated the greatest 8-h improvement after successful reperfusion (15.4 +/- 0.8 to 8.4 +/- 0.8 mm Hg [mean +/- SD], p < 0.05) but was unchanged without reperfusion (13.7 +/- 0.9 to 13.9 +/- 0.8 mm Hg, p = NS). Additionally, persistently elevated right atrial pressure was associated with increased mortality. CONCLUSIONS: Reperfusion in the setting of right ventricular infarction leads to rapid hemodynamic improvement and may result in improved survival.

Aged↗