Stanton Newman

The impact of microemboli during cardiopulmonary bypass on neuropsychological functioning.

Background and Purpose Microemboli have been implicated in the etiology of neuropsychological deficits after cardiopulmonary bypass. This study examined the incidence of high‐intensity transcranial signals (microemboli) and their relation to changes in neuropsychological performance after surgery. Methods Transcranial Doppler ultrasonography was used to measure middle cerebral artery blood flow velocity and detect microemboli. The number of high‐intensity transcranial signals was determined and related to a neurological examination and absolute changes in neuropsychological performance as well as the number of patients considered to exhibit a neuropsychological deficit. Data were available on 100 consenting patients undergoing routine cardiopulmonary bypass. Fifty of the patients were randomly assigned to a procedure that included a 40‐&mgr;m arterial line filter, and 50 had the procedure without any arterial line filter. Results Significantly more patients were found to have neuropsychological deficits in the group without the arterial line filter at both 8 days (P<.05) and 8 weeks (P<.03) after surgery. In addition, more “soft” neurological signs were found in the nonfiltered group 24 hours after surgery (P<.05). More high‐intensity transcranial signals were found in the nonfiltered group, and the number of high‐intensity transcranial signals was found to be related to the likelihood of a patient having a neuropsychological deficit at 8 weeks. Conclusions These data suggest that neuropsychological deficits after routine cardiopulmonary bypass are related to the number of microemboli delivered during surgery. Furthermore, the numbers of microemboli may be reduced by including a 40‐&mgr;m filter on the arterial line. (Stroke. 1994;25:1393‐1399.)

Self-management interventions for chronic illness

An increasing number of interventions have been developed for patients to better manage their chronic illnesses. They are characterised by substantial responsibility taken by patients, and are commonly referred to as self-management interventions. We examine the background, content, and efficacy of such interventions for type 2 diabetes, arthritis, and asthma. Although the content and intensity of the programmes were affected by the objectives of management of the illness, the interventions differed substantially even within the three illnesses. When comparing across conditions, it is important to recognise the different objectives of the interventions and the complexity of the issues that they are attempting to tackle. For both diabetes and asthma, the objectives are concerned with the underlying control of the condition with clear strategies to achieve the desired outcome. By contrast, strategies to deal with symptoms of pain and the consequences of disability in arthritis can be more complex. The interventions that were efficacious provide some guidance as to the components needed in future programmes to achieve the best results. But to ensure that these results endure over time remains an important issue for self-management interventions.

Effect of telehealth on use of secondary care and mortality: findings from the Whole System Demonstrator cluster randomised trial

Objective To assess the effect of home based telehealth interventions on the use of secondary healthcare and mortality. Design Pragmatic, multisite, cluster randomised trial comparing telehealth with usual care, using data from routine administrative datasets. General practice was the unit of randomisation. We allocated practices using a minimisation algorithm, and did analyses by intention to treat. Setting 179 general practices in three areas in England. Participants 3230 people with diabetes, chronic obstructive pulmonary disease, or heart failure recruited from practices between May 2008 and November 2009. Interventions Telehealth involved remote exchange of data between patients and healthcare professionals as part of patients’ diagnosis and management. Usual care reflected the range of services available in the trial sites, excluding telehealth. Main outcome measure Proportion of patients admitted to hospital during 12 month trial period. Results Patient characteristics were similar at baseline. Compared with controls, the intervention group had a lower admission proportion within 12 month follow-up (odds ratio 0.82, 95% confidence interval 0.70 to 0.97, P=0.017). Mortality at 12 months was also lower for intervention patients than for controls (4.6% v 8.3%; odds ratio 0.54, 0.39 to 0.75, P<0.001). These differences in admissions and mortality remained significant after adjustment. The mean number of emergency admissions per head also differed between groups (crude rates, intervention 0.54 v control 0.68); these changes were significant in unadjusted comparisons (incidence rate ratio 0.81, 0.65 to 1.00, P=0.046) and after adjusting for a predictive risk score, but not after adjusting for baseline characteristics. Length of hospital stay was shorter for intervention patients than for controls (mean bed days per head 4.87 v 5.68; geometric mean difference −0.64 days, −1.14 to −0.10, P=0.023, which remained significant after adjustment). Observed differences in other forms of hospital use, including notional costs, were not significant in general. Differences in emergency admissions were greatest at the beginning of the trial, during which we observed a particularly large increase for the control group. Conclusions Telehealth is associated with lower mortality and emergency admission rates. The reasons for the short term increases in admissions for the control group are not clear, but the trial recruitment processes could have had an effect. Trial registration number International Standard Randomised Controlled Trial Number Register ISRCTN43002091.

Postoperative cognitive dysfunction after noncardiac surgery: a systematic review.

This article describes a systematic review on the research into postoperative cognitive dysfunction (POCD) in noncardiac surgery to ascertain the status of the evidence and to examine the methodologies used in studies. The review demonstrated that in the early weeks after major noncardiac surgery, a significant proportion of people show POCD, with the elderly being more at risk. Minimal evidence was found that patients continue to show POCD up to 6 months and beyond. Studies on regional versus general anesthesia have not found differences in POCD. Many studies were found to be underpowered, and a number of other methodologic difficulties were identified. These include the different types of surgery in studies and variations in the number and range of neuropsychological tests used. A particular issue is the variety of definitions used to classify individuals as having POCD.

The cerebral effects of ascent to high altitudes

Cellular hypoxia is the common final pathway of brain injury that occurs not just after asphyxia, but also when cerebral perfusion is impaired directly (eg, embolic stroke) or indirectly (eg, raised intracranial pressure after head injury). We Review recent advances in the understanding of neurological clinical syndromes that occur on exposure to high altitudes, including high altitude headache (HAH), acute mountain sickness (AMS), and high altitude cerebral oedema (HACE), and the genetics, molecular mechanisms, and physiology that underpin them. We also present the vasogenic and cytotoxic bases for HACE and explore venous hypertension as a possible contributory factor. Although the factors that control susceptibility to HACE are poorly understood, the effects of exposure to altitude (and thus hypobaric hypoxia) might provide a reproducible model for the study of cerebral cellular hypoxia in healthy individuals. The effects of hypobaric hypoxia might also provide new insights into the understanding of hypoxia in the clinical setting.

A systematic review of psychosocial outcomes following education, self-management and psychological interventions in diabetes mellitus

Self-management and psychological interventions for diabetes have become increasingly common and have shown some positive impact on glycemic control. The association of such interventions with psychosocial outcomes is however, less clear. The current review examines the impact of these interventions on psychosocial outcomes including depression, anxiety, adjustment and quality of life. A systematic search of the literature was performed on Medline, Embase and Psychlit. Reference lists were screened for studies that met inclusion/exclusion criteria. Studies were coded on outcomes both over time and relative to control groups. In addition studies were classified as being principally educational, self-management or psychological in type, and the different components in the intervention were determined. Thirty-six studies were identified. Detrimental effects were not generally seen following any type of intervention. Depression seemed to be particularly improved following psychological interventions, whilst quality of life improved more following self-management interventions. A number of methodological issues, such as the specificity of measure used, characteristics of the population and type of intervention were however, influential in the impact of interventions on outcomes. It is recommended that future studies would benefit from being larger with controlled designs, using diabetes specific measures and providing clearer descriptions of intervention components. This will allow greater understanding of what contexts different interventions are most suited to, and which components are key to, improving psychological well-being and quality of life.

Exploring barriers to participation and adoption of telehealth and telecare within the Whole System Demonstrator trial: a qualitative study

BackgroundTelehealth (TH) and telecare (TC) interventions are increasingly valued for supporting self-care in ageing populations; however, evaluation studies often report high rates of non-participation that are not well understood. This paper reports from a qualitative study nested within a large randomised controlled trial in the UK: the Whole System Demonstrator (WSD) project. It explores barriers to participation and adoption of TH and TC from the perspective of people who declined to participate or withdrew from the trial.MethodsQualitative semi-structured interviews were conducted with 22 people who declined to participate in the trial following explanations of the intervention (n = 19), or who withdrew from the intervention arm (n = 3). Participants were recruited from the four trial groups (with diabetes, chronic obstructive pulmonary disease, heart failure, or social care needs); and all came from the three trial areas (Cornwall, Kent, east London). Observations of home visits where the trial and interventions were first explained were also conducted by shadowing 8 members of health and social care staff visiting 23 people at home. Field notes were made of observational visits and explored alongside interview transcripts to elicit key themes.ResultsBarriers to adoption of TH and TC associated with non-participation and withdrawal from the trial were identified within the following themes: requirements for technical competence and operation of equipment; threats to identity, independence and self-care; expectations and experiences of disruption to services. Respondents held concerns that special skills were needed to operate equipment but these were often based on misunderstandings. Respondents’ views were often explained in terms of potential threats to identity associated with positive ageing and self-reliance, and views that interventions could undermine self-care and coping. Finally, participants were reluctant to risk potentially disruptive changes to existing services that were often highly valued.ConclusionsThese findings regarding perceptions of potential disruption of interventions to identity and services go beyond more common expectations that concerns about privacy and dislike of technology deter uptake. These insights have implications for health and social care staff indicating that more detailed information and time for discussion could be valuable especially on introduction. It seems especially important for potential recipients to have the opportunity to discuss their expectations and such views might usefully feed back into design and implementation.

Cerebral Emboli and Cognitive Outcome After Cardiac Surgery

There have been major advancements in cardiac surgery over the past two decades, with a concomitant decrease in mortality and major morbidity. However, several recent studies have demonstrated that cardiac surgery poses significant risk for negative neurologic and neuropsychologic outcome. Although very few patients die as a result of cardiac surgery, more than two thirds of the patients demonstrate evidence of neuropsychologic dysfunction postoperatively. The mechanisms contributing to post-cardiopulmonary bypass neuropsychologic deficits are uncertain. However, two major interrelated etiologic factors, hypoperfusion and emboli, are suggested as probable culprits. It is important to define the relationship between these two putative mechanisms and postoperative neuropsychologic outcome in order to either prevent the problem or treat the effects of emboli or hypoperfusion. For example, if embolism is the cause of the deficits, increasing cerebral perfusion would deliver more emboli and increase the amount of severity of injury. Conversely, if hypoperfusion is the cause of the injury, then decreasing brain blood flow would increase the likelihood of injury. If both are important, their relative significance must be established, then one prevented and the effects of the other treated. This report discusses the methodology for detecting cerebral emboli during cardiac surgery. The incidence and severity of neuropsychologic deficits after cardiac surgery are discussed, as well as emboli in relation to composition and time of occurrence and their effect on neuropsychologic outcome.

Cost effectiveness of telehealth for patients with long term conditions (Whole Systems Demonstrator telehealth questionnaire study): nested economic evaluation in a pragmatic, cluster randomised controlled trial.

Objective To examine the costs and cost effectiveness of telehealth in addition to standard support and treatment, compared with standard support and treatment. Design Economic evaluation nested in a pragmatic, cluster randomised controlled trial. Setting Community based telehealth intervention in three local authority areas in England. Participants 3230 people with a long term condition (heart failure, chronic obstructive pulmonary disease, or diabetes) were recruited into the Whole Systems Demonstrator telehealth trial between May 2008 and December 2009. Of participants taking part in the Whole Systems Demonstrator telehealth questionnaire study examining acceptability, effectiveness, and cost effectiveness, 845 were randomised to telehealth and 728 to usual care. Interventions Intervention participants received a package of telehealth equipment and monitoring services for 12 months, in addition to the standard health and social care services available in their area. Controls received usual health and social care. Main outcome measure Primary outcome for the cost effectiveness analysis was incremental cost per quality adjusted life year (QALY) gained. Results We undertook net benefit analyses of costs and outcomes for 965 patients (534 receiving telehealth; 431 usual care). The adjusted mean difference in QALY gain between groups at 12 months was 0.012. Total health and social care costs (including direct costs of the intervention) for the three months before 12 month interview were £1390 (€1610;

Psychosocial interventions for caregivers of people with dementia: A systematic review

2150) and £1596 for the usual care and telehealth groups, respectively. Cost effectiveness acceptability curves were generated to examine decision uncertainty in the analysis surrounding the value of the cost effectiveness threshold. The incremental cost per QALY of telehealth when added to usual care was £92 000. With this amount, the probability of cost effectiveness was low (11% at willingness to pay threshold of £30 000; >50% only if the threshold exceeded about £90 000). In sensitivity analyses, telehealth costs remained slightly (non-significantly) higher than usual care costs, even after assuming that equipment prices fell by 80% or telehealth services operated at maximum capacity. However, the most optimistic scenario (combining reduced equipment prices with maximum operating capacity) eliminated this group difference (cost effectiveness ratio £12 000 per QALY). Conclusions The QALY gain by patients using telehealth in addition to usual care was similar to that by patients receiving usual care only, and total costs associated with the telehealth intervention were higher. Telehealth does not seem to be a cost effective addition to standard support and treatment. Trial registration ISRCTN43002091.