Adding value to laboratory medicine: a professional responsibility

Laboratory medicine is a medical specialty at the centre of healthcare. When used optimally laboratory medicine generates knowledge that can facilitate patient safety, improve patient outcomes, shorten patient journeys and lead to more cost-effective healthcare. Optimal use of laboratory medicine relies on dynamic and authoritative leadership outside as well as inside the laboratory. The first responsibility of the head of a clinical laboratory is to ensure the provision of a high quality service across a wide range of parameters culminating in laboratory accreditation against an international standard, such as ISO 15189. From that essential baseline the leadership of laboratory medicine at local, national and international level needs to ‘add value’ to ensure the optimal delivery, use, development and evaluation of the services provided for individuals and for groups of patients. A convenient tool to illustrate added value is use of the mnemonic ‘SCIENCE’. This tool allows added value to be considered in seven domains: standardisation and harmonisation; clinical effectiveness; innovation; evidence-based practice; novel applications; cost-effectiveness; and education of others. The assessment of added value in laboratory medicine may be considered against a framework that comprises three dimensions: operational efficiency; patient management; and patient behaviours. The profession and the patient will benefit from sharing examples of adding value to laboratory medicine

Flow instability of centre-body diffusers at supersonic speeds

This note offers explanations for certain types of flow instability which occur with centre-body diffusers at supersonic speeds. These instabilities manifest themselves as oscillations of the shock pattern ahead of the diffuser and the flow through the diffuser for certain conditions of operation and are likely to affect seriously the performance. Two main types of oscillation have been distinguished : a violent oscillation which occurs when the flow through the diffuser is throttled below a certain value ; a less severe oscillation which occurs when the vortex sheet from the intersection of the shock waves ahead of the diffuser or a separated boundary layer strikes the cowl. The explanations of the oscillations are substantiated by schliere'n photographs of two- and three-dimensional model diffuser tests in a wind tunnel. It seems possible, in the light of the explanation given in this note, to be able to predict the range of instability of any centre-body diffuser configuration by fairly simple model tests

Favourable results from predictive testing in Huntington's Disease: an exploration of the long-term impact on close relationships

Background: Huntington’s disease (HD) is a chronic neurodegenerative condition caused by a genetic mutation. H D is incurable and affects a person’s cognitive,behavioural, emotional and motor functioning. Symptoms typically develop around 30- 45 years old with life expectancy approximately 15-20 years from onset. Children of an affected parent are at 50 per cent risk of inheriting the disease, and those individuals who inherit the abnormal gene will eventually be affected by HD. The H D gene was discovered in 1993 which resulted in a direct genetic test which could confirm the absence or presence of H D in at-risk individuals. There is a large amount of research into the psychological consequences of predictive testing, with more interest in those individuals who receive unfavourable test results. Less is known about those who receive favourable results and it is has been suggested that those individuals do not always experience uncomplicated relief.Research Aim: The study aimed to explore how receiving a favourable result from predictive testing for H D can impact on close relationships in the long-term.Methodology: A constructivist grounded theory approach was used to meet the aim of the study, generating data through in-depth interviews with 10 people who received favourable results from predictive testing for H D at least five years previously. The interviews were transcribed verbatim and analysed line-by-line using a series of coding procedures.Findings: The findings suggest that when people find out they are at risk of H D they face a journey into the unknown and have to try to manage the uncertainty related to living at risk. Making the decision to be tested ends this uncertainty and once people receive a favourable result from predictive testing for HD, they go through a process of trying to distance themselves from HD. Those who have close family members (siblings in particular) with H D or who are at risk of H D can find this process more challenging.Having a sense of duty to family members with H D explains some of the difficulties faced by the participants.Conclusions: The findings of this study could help raise awareness of the long-term issues and support needs affecting individuals who receive favourable results from genetic testing. Implications of the findings for clinical practice are discussed, and recommendations for research are made

The effect of a spike protruding in front of a bluff body at supersonic speeds

Wind-tunnel tests at M = 1.5, 1.6 and 1.8 are described in which the effect of mounting a stem, with different nose pieces, on the forward face of a bluff-nosed body is studied. The drag on the front face of the body was derived from pressure measurements for different projections of the stem. Schlieren equipment was used and several interesting phenomena observed in the flow are discussed, in particular a flow oscillation resembling that which sometimes occurs with centre-body intakes

A frost-point hygrometer for supersonic wind tunnels

This report describes a frost-point hygrometer suitable for measuring the water-vapour content of the air in supersonic wind tunnels at any stagnation pressure within their present range of operatiom It uses CO2 as a coolant and is economical in construction and operation

Traceability in laboratory medicine: what is it and why is it important for patients?

The between method variability of patient results is a source of uncertainty that can have adverse consequences for patient safety and clinical outcomes. Globalisation requires that laboratory medicine results should be transferable between methods. Traceability in laboratory medicine aims to reduce between method variability so that results are independent of time or location. Application of the metrological traceability chain facilitates a universal approach based around the preparation, adoption and use of higher order international commutable reference materials and reference measurement procedures, supported by expert reference laboratories. Global collaboration is required, involving several different stakeholder groups ranging from international experts to laboratory medicine specialists in routine clinical laboratories

Attitudes and perceptions of health professionals towards management of hypothyroidism in general practice:a qualitative interview study

Objective To explore the attitudes and perceptions of health professionals towards management of hypothyroidism that contributes to the suboptimal treatment of hypothyroidism in general practice. Design A qualitative interview study using semistructured interviews. Participants Sixteen participants were interviewed between March and August 2016 comprising nine general practitioners (GPs), four pharmacists, two practice nurses and one nurse practitioner. Setting General practice and community pharmacies in the counties of Northumberland, Tyne and Wear, Stocktonon- Tees and North Cumbria, North of England, UK. Method A grounded-theory approach was used to generate themes from interviews, which were underpinned by the theory of planned behaviour to give explanation to the data. Results Although health professionals felt that hypothyroidism was easy to manage, GPs and nurses generally revealed inadequate knowledge of medication interactions and levothyroxine pharmacokinetics. Pharmacists felt limited in the advice that they provide to patients due to lack of access to patient records. Most GPs and nurses followed local guidelines, and relied on blood tests over clinical symptoms to adjust levothyroxine dose. The information exchanged between professional and patient was usually restricted by time and often centred on symptoms rather than patient education. Health professionals felt that incorrect levothyroxine adherence was the main reason behind suboptimal treatment, although other factors such as comorbidity and concomitant medication were mentioned. Enablers perceived by health professionals to improve the management of hypothyroidism included continuity of care, blood test reminders, system alerts for interfering medications and prescription renewal, and accessible blood tests and levothyroxine prescriptions for patients. Conclusion There is a significant health professional behavioural component to the management of hypothyroidism. Addressing the differences in patient and professional knowledge and perceptions could reduce the barriers to optimal treatment, while continuity of care and increased involvement of pharmacists and practice nurses would help to promote optimal thyroid replacement