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D O'Leary

Publications and source records attributed to D O'Leary.

At least 19 recordsLinked to original sources
PubMed2006

Sub-specialization in general surgery: the problem of providing a safe emergency general surgical service.

BACKGROUND: The increasing subspecialization of general surgeons in their elective work may result in deskilling and create problems in providing expert care for emergency cases. To evaluate the size of the problem this study determined how often complex emergency surgical cases are treated by general surgeons working outside their own elective subspecialty. METHOD: In a district general hospital in the south of the UK serving a population of 550 000 where there is almost complete subspecialization within general surgery, 1554 patients having emergency general surgical operations were studied in a one-year review. The time an operation occurred, the seniority of the operating surgeon, the subspecialty interest of the consultant responsible for the case compared with the specialist nature of the operation was determined. RESULTS: Of 1554 patients having emergency general surgical operations, 23% (352/1554) were of a high category of complexity. Ninety were vascular procedures and were dealt with by specialist vascular surgeons on a separate rota. Of the remaining 262 operations, 78 (30%) did not match the subspecialty of the consultant surgeon responsible for their care; 56 (72%) of these occurred out of hours of which 14 (18%) had a consultant surgeon present and scrubbed in the theatre; one per month of the study. Seventy-three percent (57/78) of these were complex colorectal operations. CONCLUSION: The mismatch between the subspecialist elective interests of the consultant general surgeon and out of hours specialist major surgery needing consultant involvement occurred infrequently, and was mainly due to major lower gastrointestinal cases managed by upper gastrointestinal and breast surgeons. This has important implications for the future training of general surgeons and the provision of an emergency nonvascular general surgical service.

Emergency Service, Hospital↗
PubMed2004

Increasing film-focus distance (FFD) reduces radiation dose for x-ray examinations.

Increasing film-focus distance (FFD) from the traditional 100 cm has been shown to be an effective method of reducing dose whilst maintaining image quality. In particular, previous work increasing the FFD from 100 to 130 cm for lumbar spine examinations demonstrated an effective dose reduction of 44%. Objective. The current study continues on from this work by investigating the dose-reducing efficacy of this FFD change for pelvis X-ray examinations. Materials and methods. Dose measurements at 100 and 130 cm using thermoluminescent dosemeters were undertaken using an anthropomorphic phantom and patients. Image quality was assessed using CEC anatomical criteria and psychophysical tests. Results. The results showed that increasing the FFD results in a reduction in effective dose of 33%, with no change in image quality. The data provided in this and previous studies demonstrate the need for rapid implementation of this simple cost-effective procedure across imaging departments, leading to an important reduction in collective dose. Conclusion. The CEC recommendation of using 115 cm FFD for a number of procedures, although useful compared with 100 cm, undervalues by a factor between 2 and 3 the potential of this dose-reducing tool.

Adult↗
PubMed2003

Do CEC guidelines under-utilise the full potential of increasing kVp as a dose-reducing tool?

Increasing beam energies are well established as a radiation dose-reducing tool in diagnostic radiology. This has led to useful recommendations by the Commission of European Communities (CEC) for appropriate kVp values to be employed for a variety of examinations. The current work tests the hypothesis that kVp levels above those recommended by the CEC will result in reduced patient dose while still producing images of acceptable quality. This study explored the effect of a range of kVp levels within and above CEC recommendations for lumbar spine radiology. A phantom investigation facilitated selection of appropriate kVp levels for a patient study ( n=59): 81 kVp (CEC) and 96 kVp (non-CEC) for the AP projection and 90 kVp (CEC) and 102 kVp (non-CEC) for the lateral projection. Entrance surface and effective dose were calculated and image quality quantified using CEC image criteria and images of a detail contrast test tool. Data analysis demonstrated significant reduction in effective radiation dose for AP (29.9%) and lateral (24.6%) when a kVp value above the CEC range was employed compared with a kVp recommended by the CEC. Although significant reductions in total image quality of 18.3% and 10.1% for the antero-posterior and lateral projections, respectively, were noted, all patient images produced with all kVp values were considered acceptable by each member of the evaluative panel with all image criteria receiving a score of 2 (out of 3) or better. The psychophysical tests revealed minor non-significant reductions in visualisation scores. The current study demonstrated that kVp values outside the CEC recommended range offer reductions in dose while producing acceptable images. Practitioners should be guided, rather than constrained, by the CEC recommendations on good radiographic technique. The need for further work exploring the effect of higher energies on visualisation of subtle pathological lesions has been identified.

Female↗
PubMed2002

Delivery of formoterol from a novel multi-dose inhaler Airmax.

Using a proprietary technology known as the X-ACT system--Active-metering, Cyclone-separator Technology, a novel multi-dose inhaler (Airmax) was developed to provide accurate and consistent dosing and a high-fine particle fraction ofthe drug. Formoterol, present as a blend with lactose monohydrate was delivered from Airmax to obtain a nominal formoterol dose of 6 or 12 microg. The devices were tested using a five-stage liquid impinger and a unit dose sampling apparatus, operated under conditions specified in European Pharmacopoeia (2000). Fine-particle dose (FPD) was defined as the dose of the aerosolized drug particles with an aerodynamic diameter < 5 microm and fine particle fraction (FPF) was the ratio of FPD to the total recovered dose. Dose per actuation was found to be 97.0+/-11.5% label claim (LC) or 5.8+/-0.7 microg (n = 140), and 100+/-9.4% LC or 12+/-1.1 microg (n=440), for the 6 and 12 microg strengths, respectively. The mass median aerodynamic diameter was 2.4+/-0.1 microm (n = 14), the geometric standard deviation 2.1+/-0.1 (n = 14), and FPF 44.4+/-24% (n= 14) for both strengths. Thus, the combination of active metering and cyclone separator produces highly consistent doses of formoterol that have a large respirable fraction.

Administration, Inhalation↗
PubMed2002

Delivery of salbutamol and of budesonide from a novel multi-dose inhaler Airmax.

A novel multi-dose inhaler has been developed to closely approach the characteristics of an "ideal" inhaler. The new device, Airmax, uses proprietary technologies known as the X-ACT system to provide accurate and consistent dosing and excellent lung deposition--even at low inspiratory flow rates--combined with ease of use by the patient. Dose delivery was close to label claim, with relative standard deviation of typically around 5% for through-life emitted mass and around 10% for dose per actuation. At a flow rate (60-70 l/min), which corresponds to 4 kPa pressure drop across the device, the mean fine particle (<5 microm) dose (FPD) from 100, 200 and 400 microg strength budesonide Airmax was around 46, 98 and 244 microg, respectively. The mean FPD from 100 microg strength salbutamol Airmax was approximately 50 microg at the same flow rate. At 30 l/min, the delivered dose from Airmax is over 85% label claim with fine particle fraction of over 35%. Performance was unaffected by shaking or orientation, provided the device was not used completely upside down, and priming was not required. There was no change in dose content uniformity and aerodynamic particle-size distribution after the devices have been stored unwrapped at 30 degrees C/60% RH up to 24 months. Airmax is robust, portable and intuitive to use.

Administration, Inhalation↗
PubMed2001

The outbreak of West Nile virus infection in the New York City area in 1999.

BACKGROUND: In late August 1999, an unusual cluster of cases of meningoencephalitis associated with muscle weakness was reported to the New York City Department of Health. The initial epidemiologic and environmental investigations suggested an arboviral cause. METHODS: Active surveillance was implemented to identify patients hospitalized with viral encephalitis and meningitis. Cerebrospinal fluid, serum, and tissue specimens from patients with suspected cases underwent serologic and viral testing for evidence of arboviral infection. RESULTS: Outbreak surveillance identified 59 patients who were hospitalized with West Nile virus infection in the New York City area during August and September of 1999. The median age of these patients was 71 years (range, 5 to 95). The overall attack rate of clinical West Nile virus infection was at least 6.5 cases per million population, and it increased sharply with age. Most of the patients (63 percent) had clinical signs of encephalitis; seven patients died (12 percent). Muscle weakness was documented in 27 percent of the patients and flaccid paralysis in 10 percent; in all of the latter, nerve conduction studies indicated an axonal polyneuropathy in 14 percent. An age of 75 years or older was an independent risk factor for death (relative risk adjusted for the presence or absence of diabetes mellitus, 8.5; 95 percent confidence interval, 1.2 to 59.1), as was the presence of diabetes mellitus (age-adjusted relative risk, 5.1; 95 percent confidence interval, 1.5 to 17.3). CONCLUSIONS: This outbreak of West Nile meningoencephalitis in the New York City metropolitan area represents the first time this virus has been detected in the Western Hemisphere. Given the subsequent rapid spread of the virus, physicians along the eastern seaboard of the United States should consider West Nile virus infection in the differential diagnosis of encephalitis and viral meningitis during the summer months, especially in older patients and in those with muscle weakness.

Adolescent↗
PubMed2001

Anatomic and functional variability: the effects of filter size in group fMRI data analysis.

In the analysis of group fMRI scans, an optimal spatial filter should be large enough to accurately blend functionally homologous anatomic regions, yet small enough not to blur the functionally distinct regions. Hanning filters varying from 0.0 to 18.0 mm were evaluated in a group analysis of six healthy controls performing a simple finger-tapping paradigm. Test-retest reliability and Talairach-based measurements of the sensorimotor region were used to explore the optimal filter size. Two distinct regions of functional activation were noted in the sensorimotor cortex in group images (n = 6) at both time 1 and time 2. These regions merge once the filter size exceeds approximately 6.0 mm. The original hypothesis that these represented a motor and sensory activation was rejected on the basis of structural and functional variability. A discussion of the inherent difficulties in choosing an appropriate filter size is presented.

Adult↗
PubMed2001

Personality and outcome in depression: an 18-month prospective follow-up study.

BACKGROUND: The relationship between personality and depressive illness is complex. The aim of this study was to assess whether the presence of a personality disorder or high neuroticism (N) scores predicted longer times to discharge or remission onset or higher risks of relapse for a cohort of depressed subjects admitted for the first time. METHODS: 100 consecutive subjects with ICD-10-defined depression were recruited on admission and followed up prospectively over an 18-month period. Personality function was rated using the informant-rated Standard Assessment of Personality in addition to the self-rated Maudsley Personality Inventory. Remission onset and relapse were defined operationally by scores on the Hamilton Rating Scale using recommended criteria. RESULTS: The presence of a personality disorder predicted longer times to remission onset. Personality trait accentuation did not. Higher end N-scores correlated with longer times to remission onset. Neither personality disorder nor high N-scores predicted relapse or discharge risk. Subjects with a personality disorder were treated as aggressively as those without but those with higher N-scores were not. LIMITATIONS: It is an in-patient sample. Fifteen subjects dropped out of follow-up and those who did so were more likely to have met criteria for two or more personality disorder categories or four or more traits from one personality disorder category. The analysis assumes that state and scar effects on N-scores were minimised. Treatment decisions were not controlled. CONCLUSIONS: These findings support the view that the presence of a personality disorder and high N-scores modify the short-term course to remission onset in depression.

Adult↗
PubMed2001

Suicide in primary affective disorders revisited: a systematic review by treatment era.

BACKGROUND: We reviewed suicide rates in affective disorder and their variation with electroconvulsive therapy (ECT) and antidepressant availability. METHOD: Suicide rates were calculated from 75 follow-up studies, identified by systematic literature searches and analyzed for differences over time eras characterized by the availability of specific treatments. DATA SOURCES AND STUDY SELECTION: MEDLINE, EMBASE, BIOSIS Previews, and Psychological Abstracts literature searches were conducted for the years 1966 to 1995. References from review articles identified from these sources from 1985 onward and textbook references were also included. Publications prior to 1966 were obtained from article references identified for the period 1966 to 1976 and reviews. Inclusion criteria were (1) articles written in English, French, or German; (2) sample size > 30; (3) age at recruitment between 18 and 64 years for each subject; (4) sample had to contain subjects hospitalized at time of recruitment; and (5) naturalistic follow-up of at least 6 months. RESULTS: Suicide rates decreased with longer follow-up periods. For follow-up periods over 20 years, the mean rate was 3.76/1,000 person-years (95% confidence interval [CI] = 2.35 to 5.17). Suicides accounted for 12.3% (95% CI = 8.52 to 16.04) of all deaths in samples in which 40% or more of patients had died. For studies with minimal overlap between eras, the mean suicide rate differed significantly between eras (pretreatment, before 1940: 6.3/1000; ECT treatment, 1940 to 1959: 5.7/1,000: antidepressant treatment, 1960 onward: 3.3/1,000; F = 31.4. df = 2,42; p < .001). CONCLUSION: The risk of suicide in follow-up studies of affective disorder has decreased compared to that reported in previous reviews. The availability of ECT and antidepressants may have contributed to this decrease, but prescription of these treatments cannot be assumed for all patients.

Antidepressive Agents↗
PubMed2000

Sexual dimorphism in the human brain: evaluation of tissue volume, tissue composition and surface anatomy using magnetic resonance imaging.

Magnetic resonance imaging (MRI) was used to evaluate sex differences in brain morphology by comparing measures of brain tissue volume, brain tissue composition (proportions of gray and white matter), and measures of cortical surface anatomy. A large and well-matched sample of healthy women (n=42) and healthy men (n=42) were evaluated. There was a significant gender effect on intracranial volume, males being larger. However, this increase in size was limited to the cerebrum as there was no sex difference in the volume of the cerebellum. The gender difference in size of the cerebral volume was evenly distributed, with all four lobes equally larger in males compared to females. Gray and white matter tissue proportions were similar between the sexes globally. Regional tissue composition analysis showed sex differences within the parietal lobes with females having proportionately more gray matter on the right side. There were no differences between the sexes in cortical surface anatomy measures. Overall, against the background of similarity in morphology, there are differences between the sexes with regard to general and regional brain measures. The functional significance of these sex differences is unclear, but may represent the differential effects of gonadal hormones during brain growth and development.

Adult↗
PubMed2000

Lack of mucin MUC5AC field change expression associated with tubulovillous and villous colorectal adenomas.

BACKGROUND: MUC5AC is a secreted mucin aberrantly expressed by polypoid colorectal adenomas. It has been hypothesised that the "normal" surrounding colorectal mucosa expresses MUC5AC as a field change phenomenon that can be used to predict adenoma recurrence following resection. AIM: To determine if there is a field change of de novo MUC5AC expression in histologically normal rectal mucosa adjacent to villous and tubulovillous adenomas, and thus whether MUC5AC expression can be used as a marker of early tumour recurrence. METHODS: In a prospective cohort study paired mucosal biopsies of adenomatous and macroscopically "normal" mucosa were obtained from 11 patients with villous and 11 patients with tubulovillous adenomas who underwent primary resection for purpose of cure. The tissues were studied to determine MUC5AC gene expression by immunohistochemistry and in situ hybridisation. Patients were followed up by flexible sigmoidoscopy to detect the presence of early local recurrence. RESULTS: 10 villous adenomas showed mature MUC5AC glycoprotein and all 11 expressed MUC5AC mRNA. Five tubulovillous adenomas showed mature MUC5AC glycoprotein and 10 expressed MUC5AC mRNA. Neoexpression of the MUC5AC mucin gene was not detected in any of the mucosal biopsies taken adjacent to either villous or tubulovillous adenomas, even in three patients with early, locally recurrent disease. CONCLUSIONS: Aberrant MUC5AC gene expression is not a "field change" in the colorectal mucosa in patients with rectal adenomas and therefore cannot be used to predict local recurrence of villous and tubulovillous adenomas.

Adenoma, Villous↗
PubMed1999

Generalized cognitive deficits in schizophrenia: a study of first-episode patients.

BACKGROUND: Cognitive impairment is recognized as a core characteristic of schizophrenia. There has always been a debate about the nature, selectivity, and time of onset of these deficits in relationship to the onset of illness and treatment factors. To our knowledge, the present study represents the largest sample of mostly neuroleptic-naive patients with first-episode schizophrenia that has been reported to date. METHODS: A group of 94 patients experiencing their first episode of schizophrenic illness and 305 normal comparison subjects were administered a comprehensive clinical and neuropsychological evaluation. Seventy-three patients were neuroleptic naive, 14 had received treatment for less than 1 week, and the remaining 7 had been medicated for less than 2 weeks. RESULTS: Patients performed significantly worse than the comparison subjects on every neuropsychological variable except those assessing savings scores (ie, forgetting over time). Twenty-five of 30 tests had an effect size (ES) greater than 0.75 when the 2 groups were compared. An ES analysis within the schizophrenia group revealed that the greatest relative impairments were on the Wechsler Adult Intelligence Scale-Revised digit symbol (ES, -0.52) and comprehension (ES, -0.42) subscales. CONCLUSIONS: Our findings are in concert with others demonstrating that significant cognitive impairment across multiple ability domains is a core characteristic of schizophrenia and is not caused by chronic illness, treatment, or institutionalization. The ES analysis emphasizes that patients with schizophrenia have a generalized deficit that is not easily explained by a single anatomical region or ability area.

Adult↗
PubMed1999

First admissions for depression: is the 'no-treatment interval' a critical predictor of time to remission?

BACKGROUND: This study aimed to replicate findings that length of episode prior to adequate antidepressant treatment (the 'no-treatment interval') and premorbid neuroticism predict time to remission from the institution of adequate treatment for depression. METHODS: Eighty-three inpatients meeting ICD-10 criteria for a depressive illness were entered into an 18-month prospective follow-up study of illness course. Subjects were assessed using the Schedules for Clinical Assessment in Neuropsychiatry, Maudsley Personality Inventory (MPI) and the Hamilton Rating Scale for Depression (HRSD). Remission was defined as an HRSD score of < 8 for 2 consecutive weeks. RESULTS: Twenty-two patients (27%) remained depressed 12 months after the onset of adequate treatment. Significantly longer times to remission were predicted by a longer no-treatment interval and higher premorbid neuroticism scores. LIMITATIONS: Adequate antidepressant treatment was commenced prior to admission in half the cases, requiring a retrospective assessment of illness course prior to study entry. Twenty-four patients (29%) had not remitted at the time of completion of the MPI. CONCLUSIONS: These results replicate previous findings identifying a longer time to treatment and higher neuroticism scores as predictors of chronicity in depression.

Adolescent↗
PubMed1998

Time to initial medical presentation in a first-admission group with depression.

This paper examines the interval between the onset of depressive illness and subsequent medical presentation in a group of patients undergoing their first psychiatric admission with moderate to severe depression. The average preconsultation interval was 76 days, compared with an average time from consultation to the commencement of adequate treatment of 40 days. The time to initial consultation was found to correlate significantly with neuroticism, but not with sociodemographic factors. This study suggests that neuroticism may act as a predictor of poor outcome in depressive illness through its impact on help-seeking behaviour.

Adolescent↗