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Biomedical subjects

C Wilkinson

Publications and source records attributed to C Wilkinson.

At least 19 recordsLinked to original sources
PubMed2005

Maternal and neonatal side-effects of remifentanil patient-controlled analgesia in labour.

BACKGROUND: Remifentanil has been suggested as an ideal opioid for patient-controlled analgesia (PCA) in labour, but the safety profile has not been established. The aims of this preliminary prospective observational study were to investigate the maternal side-effects and early neonatal effects, and to assess the placental transfer of remifentanil PCA during labour. METHODS: Women with no known obstetric complications or contraindication to remifentanil were recruited (n=50). Remifentanil was administered at a bolus dose of 0.5 microg kg(-1) and a lockout period of 2 min. A visual analogue scale was used to assess pain, nausea and itching. Maternal observations were recorded hourly and fetal heart rate trace was assessed every 2 h. Umbilical cord gases, 1 and 5 min Apgar scores and neurological evaluation of the neonate were recorded. Maternal venous blood and umbilical artery and vein cord blood samples were collected for analysis of remifentanil concentration. RESULTS: Fifty women enrolled in the study (24 multiparous, 26 primiparous). There was no evidence of cardiovascular instability or respiratory depression. Pain scores decreased significantly, but there was no significant change in nausea after initiating the PCA. A statistically significant increase in itching was found to be clinically mild and 22 women were slightly drowsy (95% confidence interval [CI], 30-58.7%) but alert to voice. Ten fetal heart rate traces demonstrated changes in the first 20 min, but did not require intervention (95% CI, 10-33.7%). The median 1 and 5 min Apgar scores were 9. The mean umbilical cord gases and neurological examination were within normal limits. Maternal vein and umbilical vein cord samples demonstrated placental transfer of remifentanil, and small amounts were detected in umbilical artery samples. CONCLUSIONS: At the bolus dose used remifentanil PCA has an acceptable level of maternal side-effects and minimal effect on the neonate. Remifentanil crosses the placenta and appears to be either rapidly metabolized or redistributed in the neonate.

Adolescent↗
PubMed2005

Interventions for asymptomatic retinal breaks and lattice degeneration for preventing retinal detachment.

BACKGROUND: Asymptomatic retinal breaks and lattice degeneration are visible lesions that are risk factors for later retinal detachment. Retinal detachments occur when fluid in the vitreous cavity passes through tears or holes in the retina and separates the retina from the underlying retinal pigment epithelium. Creation of an adhesion surrounding retinal breaks and lattice degeneration, with laser photocoagulation or cryotherapy, has been recommended as an effective means of preventing retinal detachment. This therapy is of value in the management of retinal tears associated with the symptoms of flashes and floaters and persistent vitreous traction upon the retina in the region of the retinal break, because such symptomatic retinal tears are associated with a high rate of progression to retinal detachment. Retinal tears and holes unassociated with acute symptoms and lattice degeneration are significantly less likely to be the sites of retinal breaks that are responsible for later retinal detachment. Nevertheless, treatment of these problems is frequently recommended, in spite of the fact that the effectiveness of this therapy is unproven. OBJECTIVES: The purpose of this review is to evaluate the effectiveness of interventions for asymptomatic retinal breaks and lattice degeneration. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials - CENTRAL (which includes the Cochrane Eyes and Vision Group Trials Register) on The Cochrane Library (Issue 3 2004) MEDLINE (1966 to July 2004) and EMBASE (1980 to August 2004). Textbooks regarding retinal detachment and the reference lists of relevant reports were reviewed for additional study reports. Experts in the field were contacted for details of other published and unpublished studies. SELECTION CRITERIA: This review was designed to include randomised controlled trials in which one treatment for asymptomatic retinal breaks and lattice degeneration was compared to another treatment or to no treatment. DATA COLLECTION AND ANALYSIS: One reviewer assessed the search results and collected relevant studies. Since no studies met the inclusion criteria, no studies were assessed for methodological quality. No data were extracted and no meta-analysis could be performed. MAIN RESULTS: No trials were found that met the inclusion criteria for this review. AUTHORS' CONCLUSIONS: No conclusions could be reached about the effectiveness of surgical interventions to prevent retinal detachment in eyes with asymptomatic retinal breaks and/or lattice degeneration. Some current recommendations for treatment, based upon a consensus of expert opinion, are contradicted by the best available evidence.

Humans↗
PubMed2005

A micro costing of NHS cancer genetic services.

This paper presents the first full micro costing of a commonly used cancer genetic counselling and testing protocol used in the UK. Costs were estimated for the Cardiff clinic of the Cancer Genetics Service in Wales by issuing a questionnaire to all staff, conducting an audit of clinic rooms and equipment and obtaining gross unit costs from the finance department. A total of 22 distinct event pathways were identified for patients at risk of developing breast, ovarian, breast and ovarian or colorectal cancer. The mean cost per patient were pound sterling 97- pound sterling 151 for patients at moderate risk, pound sterling 975- pound sterling 3072 for patients at high risk of developing colorectal cancer and pound sterling 675- pound sterling 2909 for patients at high risk of developing breast or ovarian cancer. The most expensive element of cancer genetic services was labour. Labour costs were dependent upon the amount of labour, staff grade, number of counsellors used and the proportion of staff time devoted to indirect patient contact. With the growing demand for cancer genetic services and the growing number of national and regional cancer genetic centers, there is a need for the different protocols being used to be thoroughly evaluated in terms of costs and outcomes.

Costs and Cost Analysis↗
PubMed2004

Estimating the survival benefits gained from providing national cancer genetic services to women with a family history of breast cancer.

The aim of this paper is to compare a service offering genetic testing and presymptomatic surveillance to women at increased risk of developing breast cancer with its predecessor of no service at all in terms of survival and quality-adjusted survival (QALYs) by means of a Markov cohort chain simulation model. Genetic assessment and presymptomatic care provided between 0.07-1.61 mean additional life years and 0.05-1.67 mean QALYs over no services. Prophylactic surgery and surveillance extended mean life expectancy by 0.41-1.61 and 0.32-0.99 years, respectively over no services for high-risk women. Model outcomes were sensitive to all the parameters varied in the sensitivity analysis. Providing cancer genetic services increase survival and as long as services do not induce adverse psychological effects they also provide more QALYs. The greatest survival and QALY benefits were found for women with identified mutations. As more cancer genes are identified, the survival and cost-effectiveness of genetic services will improve. Although mastectomy provided most additional life years, when quality of life was accounted for oophorectomy was the optimal strategy. Delayed entry into coordinated genetic services was found to diminish the average survival and QALY gains for a woman utilising these services.

Adult↗
PubMed2003

Detergent structure in crystals of the integral membrane light-harvesting complex LH2 from Rhodopseudomonas acidophila strain 10050.

Integral membrane proteins are solubilized by their incorporation into a detergent micelle. The detergent micelle has a critical influence on the formation of a three-dimensional crystal lattice. The bulk detergent phase is not seen in X-ray crystal structures of integral membrane proteins, due to its disordered character. Here, we describe the detergent structure present in crystals of the peripheral light-harvesting complex of the purple bacteria Rhodopseudomonas acidophila strain 10050 at a maximal resolution of 12A as determined by neutron crystallography. The LH2 molecule has a toroidal shape and spans the membrane completely in vivo. A volume of 16% of the unit cell could be ascribed to detergent tails, localized on both the inner and outer hydrophobic surfaces of the molecule. The detergent tail volumes were found to be associated with individual LH2 molecules and had no direct role in the formation of the crystalline lattice.

Crystallization↗
PubMed2003

Welsh women's comments about breast problems and the care given: a qualitative study in the community.

The aim of this study was to undertake a systematic analysis, using qualitative software, of the free text comments from a postal survey exploring women's experiences of breast symptoms, their expectations of treatment, knowledge of breast cancer risk factors and perceptions of risk, in 34 group general practices in South Wales. The 959 women who returned the questionnaire, out of 1126 (response rate 85%), comprised 497 women who consulted their general practitioner (GP) with a new breast symptom during the baseline data collection period and 462 controls who had not. When the survey was conducted the researchers did not know whether these women had cancer or had previously been treated for it. One-third (33.1%) of those returning the survey (n = 318) wrote comments. Compared to the rest, they were significantly more likely to have consulted their GP for a new breast symptom and to have stayed on at school and/or gone on to more education or training. The majority wrote about their own experience of breast symptoms and/or the care received in primary and secondary settings. The general tone was factual and when evaluation took place positive comments were more frequent than negative ones. Nothing suggested that the respondents had been upset or made more anxious by the preceding questions on such a potentially sensitive topic. Free text comments gathered in surveys can provide valuable data if systematically analysed. Doctors, particularly GPs, can be reassured that more women in this community sample who expressed an opinion on care were positive. The negative comments, however, highlight issues that still need to be addressed in therapeutic relationships.

Adolescent↗
PubMed2003

Estimating psychological treatment effects from a randomised controlled trial with both non-compliance and loss to follow-up.

BACKGROUND: The Outcomes of Depression International Network (ODIN) trial evaluated the effect of two psychological interventions for the treatment of depression in primary care. Only about half of the patients in the treatment arm complied with the offer of treatment, prompting the question:'what was the effect of treatment in those patients who actually received it?' AIMS: To illustrate the estimation of the effect of receipt of treatment in a randomised controlled trial subject to non-compliance and loss to follow-up. METHOD: We estimated the complier average causal effect (CACE) of treatment. RESULTS: In the ODIN trial the effect of receipt of psychological intervention (an average of about 4 points on the Beck Depression Inventory) is about twice that of offering it. CONCLUSIONS: The statistical analysis of the results of a clinical trial subject to non-compliance to allocated treatment is now reasonably straightforward through estimation of a CACE and investigators should be encouraged to present the results of analyses of this type as a routine component of a trial report.

Data Interpretation, Statistical↗
PubMed2002

The development of a new site-specific measure of quality of life for breast problems: the Cardiff breast scales.

The management of women presenting to primary care with symptoms of breast disease is of increasing interest given recent organisational changes aimed at improving accuracy and speed of referrals. As part of a randomised controlled trial, 1063 women were recruited following a primary care consultation for a variety of breast-related problems. In the absence of a suitable outcome measure for such women, a site-specific instrument was developed to complement a generic quality of life scale (SF-36). Items were generated using key informant interviews with health professionals. Draft scale items were piloted using a postal questionnaire and subsequent patient debrief interviews. A sample of respondents were also sent the same questionnaire I month later to assess test-retest reliability. Across the whole sample (n = 848), three factors were identified: 'general well-being', 'concerns' and 'relationships'. These factors accounted for 60% of total variance. Evidence of scale validity, reliability and responsiveness are reported for this new outcome measure for use in women presenting with breast problems.

Breast Diseases↗
PubMed2002

It doesn't cost anything just to ask, does it? The ethics of questionnaire-based research.

Patient-based outcome measures are increasingly important in health care evaluations, often through the use of paper-based questionnaires. The likely impact of questionnaires upon patients is not often considered and therefore, the balance of benefit and harm not fully explored. Harms that might accrue for research staff are even less frequently considered. This paper describes the use of postal questionnaires within a study of breast disease management in primary care. Questionnaire responses are used to describe the nature of discomfort or harms that may occur in such studies. Ethical issues raised by the harms are discussed in relation to the benefits of the study. Practical suggestions for reducing harm to patients are proposed. A secondary consideration, discomfort to the researcher, is also identified and suggestions made to reduce its effect. Finally, the role of research questionnaires as a study intervention is discussed.

Biomedical Research↗
PubMed2002

Provision of Chlamydia trachomatis screening in family planning clinics and emergency contraception in genitourinary medicine clinics: a collaborative cross-speciality survey.

Two surveys were undertaken to review (1) provision of Chlamydia trachomatis screening by family planning (FP) clinics in the London region and (2) access to emergency contraception (EC) from genitourinary#10; medicine (GUM) clinics within the former North Thames region. The findings from the first survey suggest that there is insufficient screening (and treatment) in vulnerable groups attending FP clinics. Results#10; from the second survey show that hormonal EC is widely available from within GUM clinics, and those clinics also provide a range of other contraception services. However, these details may not be widely#10; recognised either by policymakers or the general public. #10;

Ambulatory Care Facilities↗
PubMed2001

Rapid neutron-diffraction data collection for hydrogen-bonding studies: application of the Laue diffractometer (LADI) to the case study zinc (tris)thiourea sulfate.

The successful application of the newly developed image-plate neutron Laue diffractometer (LADI) at the Institut Laue-Langevin (ILL), Grenoble, France, for rapid hydrogen-bonding characterization is reported. The case study concerns the promising non-linear optical material zinc (tris)thiourea sulfate (ZTS), which contains 30 atoms in the asymmetric unit and crystallizes in the orthorhombic space group, Pca2(1), a = 11.0616 (9), b = 7.7264 (6), c = 15.558 (1) A [T = 100.0 (1) K]. The results from a 12 h data collection from ZTS on LADI are compared with those obtained over 135 h using the monochromatic four-circle diffractometer D9 at the same reactor source with a crystal 13 times larger in volume. Both studies reveal the extensive hydrogen bonding and other close non-bonded contacts within the material. As expected, the results from D9 are more precise than those obtained from LADI; however, the bond geometry determined from the two experiments is the same within the larger estimated standard deviations. Furthermore, the conclusions drawn from the two studies separately regarding the nature of all supramolecular features are identical. This illustrates that LADI is eminently suitable for rapid characterization of hydrogen-bonded structures by neutron diffraction, with the gain in speed compared with traditional instrumentation being several orders of magnitude.

Journal Article↗
PubMed2001

Antenatal day care units versus hospital admission for women with complicated pregnancy.

BACKGROUND: The use of antenatal day care units is widely recognized as an alternative for inpatient care for women with complicated pregnancy. OBJECTIVES: The objective of this review was to assess the clinical safety, plus maternal, perinatal and psychosocial consequences for the women and cost effectiveness of this type of care. SEARCH STRATEGY: The Group's Specialised Register of Controlled Trials was searched in May 2001 as well as the Cochrane Controlled Trials Register (CENTRAL/CCTR), CINAHL (1982-04 to 1998-10) and Current Contents (Life Sciences/Clinical Medicine 1995-05 to 1999). Conference proceedings of PSANZ (Perinatal Society of Australia and New Zealand) and FIGO (Fédération Internationale de Gynécologie et d'Obstétrie) (1997) were searched. SELECTION CRITERIA: Randomized trial comparing day care with inpatient care for women with complicated pregnancy. DATA COLLECTION AND ANALYSIS: Trial quality was assessed by two reviewers independently. The author of the study was contacted for additional information. Data were extracted by the same two reviewers independently. MAIN RESULTS: One trial involving 54 women was included. This trial was of average quality. It was found that day care assessment for non-proteinuric hypertension can reduce inpatient stay (difference in mean stay: 4.0 days; 95% confidence interval (CI): 2.1 to 5.9 days). Also a significant increase in the rate of induction of labour in the control group was found (4.9 times more likely: 95% CI: 1.6 to 13.8). The other clinical outcomes did not show a statistically significant difference between the control and intervention group. No other significant differences were observed. REVIEWER'S CONCLUSIONS: Admission to day care for non-proteinuric hypertension reduces the amount of time spent in the hospital and proportion of women induced for labour. However, one trial of 54 women is not sufficient to draw sound conclusions. Additional studies are needed to give more solid evidence to confirm the advantages of antenatal day care units.

Cost-Benefit Analysis↗
PubMed2001

Interventions for asymptomatic retinal breaks and lattice degeneration for preventing retinal detachment.

BACKGROUND: Asymptomatic retinal breaks and lattice degeneration are visible lesions that are risk factors for later retinal detachment. Retinal detachments occur when fluid in the vitreous cavity passes through tears or holes in the retina and separates the retina from the underlying retinal pigment epithelium. Creation of an adhesion surrounding retinal breaks and lattice degeneration, with laser photocoagulation or cryotherapy, has been recommended as an effective means of preventing retinal detachment. This therapy is of value in the management of retinal tears associated with the symptoms of flashes and floaters and persistent vitreous traction upon the retina, because such symptomatic retinal breaks are associated with a high rate of progression to retinal detachment. Retinal tears and holes unassociated with acute symptoms and lattice degeneration are significantly less likely to be the sites of retinal breaks that are responsible for later retinal detachment. Nevertheless, treatment of these problems is frequently recommended, in spite of the fact that the effectiveness of this therapy is unproven. OBJECTIVES: The purpose of this review is to evaluate the effects of interventions for asymptomatic retinal breaks and lattice degeneration. SEARCH STRATEGY: We searched the Cochrane Controlled Trials Register - CENTRAL (which includes the Cochrane Eyes and Vision Group specialized register), MEDLINE and EMBASE. Textbooks regarding retinal detachment and the reference lists of relevant reports were reviewed in an effort to find additional study reports. Experts in the field were contacted for details of other published and unpublished studies. SELECTION CRITERIA: This review was designed to include randomised controlled trials in which one treatment for asymptomatic retinal breaks and lattice degeneration was compared to another treatment or to no treatment. DATA COLLECTION AND ANALYSIS: One reviewer assessed the search results and collected relevant studies. Since no studies met the inclusion criteria, no studies were assessed for methodological quality. No data were extracted and no meta-analysis could be performed. MAIN RESULTS: No trials were found that met the inclusion criteria for this review. REVIEWER'S CONCLUSIONS: No conclusions could be reached about the effects of surgical interventions to prevent retinal detachment in eyes with asymptomatic retinal breaks and/or lattice degeneration. Some current recommendations for treatment, based upon a consensus of expert opinion, are contradicted by the best available evidence.

Humans↗
PubMed2001

Nantotechniques and approaches in biotechnology.

Nanotechnology has enabled the development of an amazing variety of methods for fabricating nanotopography and nanopatterned chemistry in recent years. Some of these techniques are directed towards producing single component particles, as well as multi-component assembly or self-assembly. Other methods are aimed at nanofeaturing and patterning surfaces that have a specific chemistry or topography. This article concentrates mainly on surface-directed nanobiotechnologies because they are nearer to commercial realisation, such as use in tissue engineering, control of biofouling and cell culture, than those directed at producing nanoparticles.

Animals↗
PubMed2001

Measuring the involvement of patients in shared decision-making: a systematic review of instruments.

We wanted to determine whether research instruments exist which focus on measuring to what extent health professionals involve patients in treatment and management decisions. A systematic search and appraisal of the relevant literature was conducted by electronic searching techniques, snowball sampling and correspondence with field specialists. The instruments had to concentrate on assessing patient involvement in decision-making by observation techniques (either direct or using audio or videotaped data) and contain assessments of the core aspects of 'involvement', namely evidence of patients being involved (explicitly or implicitly) in decision-making processes, a portrayal of options and a decision-making or deferring stage. Eight instruments met the inclusion criteria. But we did not find any instruments that had been specifically designed to measure the concept of 'involving patients' in decisions. The results reveal that little attention has been given to a detailed assessment of the processes of patient involvement in decision-making. The existing instrumentation only includes these concepts as sub-units within broader assessments, and does not allow the construct of patient involvement to be measured accurately. Instruments developed to measure 'patient-centeredness' are unable to provide enough focus on 'involvement' because of their attempt to cover so many dimensions. The concept of patient involvement (shared decision-making; informed collaborative choice) is emerging in the literature and requires an accurate method of assessment.

Decision Making↗
PubMed2001

Administration of blood transfusions to adults in general hospital settings: a review of the literature.

The Serious Hazards of Transfusion (SHOT) haemovigilance scheme for the United Kingdom and Republic of Ireland has clearly indicated that there are avoidable risks to which recipients of blood transfusion are exposed. Sometimes errors in practice have led to serious and even fatal consequences, particularly when a haemolytic response occurs due to an incompatible transfusion. Despite the risks, blood transfusion is an important and frequently life-saving therapy and its use in clinical practice is common. This paper discusses recently published national guidelines for the care of recipients of blood transfusion in the light of a review of the literature relevant to the administration of blood transfusions to adults in general hospital settings. Recommendations for practitioners, managers and teachers are offered in relation to preventing errors and to patient care associated with blood transfusion in the context of contemporary emphasis upon evidence based care.

Adult↗