PubMed Health⌕ Search

Biomedical subjects

R L Smyth

Publications and source records attributed to R L Smyth.

At least 19 recordsLinked to original sources
PubMed2000

Temperature measured at the axilla compared with rectum in children and young people: systematic review.

OBJECTIVE: To evaluate the agreement between temperature measured at the axilla and rectum in children and young people. DESIGN: A systematic review of studies comparing temperature measured at the axilla (test site) with temperature measured at the rectum (reference site) using the same type of measuring device at both sites in each patient. Devices were mercury or electronic thermometers or indwelling thermocouple probes. STUDIES REVIEWED: 40 studies including 5528 children and young people from birth to 18 years. DATA EXTRACTION: Difference in temperature readings at the axilla and rectum. RESULTS: 20 studies (n=3201 (58%) participants) had sufficient data to be included in a meta-analysis. There was significant residual heterogeneity in both mean differences and sample standard deviations within the groups using different devices and within age groups. The pooled (random effects) mean temperature difference (rectal minus axillary temperature) for mercury thermometers was 0.25 degrees C (95% limits of agreement -0.15 degrees C to 0.65 degrees C) and for electronic thermometers was 0. 85 degrees C (-0.19 degrees C to 1.90 degrees C). The pooled (random effects) mean temperature difference (rectal minus axillary temperature) for neonates was 0.17 degrees C (-0.15 degrees C to 0. 50 degrees C) and for older children and young people was 0.92 degrees C (-0.15 degrees C to 1.98 degrees C). CONCLUSIONS: The difference between temperature readings at the axilla and rectum using either mercury or electronic thermometers showed wide variation across studies. This has implications for clinical situations where temperature needs to be measured with precision.

Adolescent↗
PubMed2000

Randomized controlled trials in cystic fibrosis (1966-1997) categorized by time, design, and intervention.

The improved prognosis of cystic fibrosis (CF) over the last three decades has been associated with an increased use of a range of treatments, but it is important that the use of an individual treatment is based on evidence. Well-designed randomized controlled trials (RCTs) are a robust method for evaluating the effectiveness of such treatments. We have developed a register of RCTs in CF and have studied when they were performed, their design, and what interventions were investigated. We identified 506 RCTs; 37.5% were identified solely as abstract reports in conference proceedings. There has been about a 30-fold increase in the number of RCTs in CF since 1966. A high proportion of the RCTs (72.7%) had a sample size of 30 or less, and only 8.7% were multicenter trials. Reporting of study design was poor: in 51.4% the report did not state whether there was any blinding in the trial design; 53.6% of studies were of crossover design. The most common interventions studied were antibiotic treatments and physiotherapy, but a number of commonly used therapies had been evaluated only in a small number of patients. Although the number of RCTs of interventions in CF patients has increased over the last 25 years, the sample sizes of these trials are generally too small to indicate whether the intervention was effective, and very few were multicenter. Future RCTs in CF are more likely to provide clinically useful answers if higher numbers of patients are recruited into large, well-designed multicenter trials. This should be a priority of the organization of future research in CF.

Cystic Fibrosis↗
PubMed2000

Oral protein calorie supplementation for children with chronic disease.

BACKGROUND: Growth failure and poor nutritional status are common features in children with chronic diseases due to reduced appetite, malabsorption and increased nutritional requirements associated with some diseases. The provision of oral protein calorie supplements is one of a number of interventions used to improve nutritional status in these children. The use of these products, which are expensive, may be associated with a number of adverse effects, for example, they may effect development of normal eating behaviour patterns or lead to unpleasant symptoms such as vomiting and diarrhoea. OBJECTIVES: To examine the evidence that in children with chronic disease, oral protein calorie supplements alter daily nutrient intake, nutritional indices, survival and quality of life and are associated with adverse effects, for example diarrhoea, vomiting, reduced appetite, glucose intolerance, bloating and eating behaviour problems. SEARCH STRATEGY: All publications describing RCTs of the use of oral protein calorie supplements in children with chronic diseases were identified through comprehensive electronic database searches, handsearching relevant journals and handsearching abstract books of conference proceedings. The companies which market oral protein calorie supplements were also contacted. SELECTION CRITERIA: All randomised or quasi-randomised controlled trials comparing use of oral protein calorie supplements for at least one month to increase calorie intake with existing conventional therapy, which may include nutritional advice on how to improve nutritional intake from food or no specific intervention, in children with chronic disease. DATA COLLECTION AND ANALYSIS: The following outcomes were assessed: indices of nutrition and growth, anthropometric measures of body composition, calorie and nutrient intake (total, from oral protein calorie supplements and from food), eating behaviour, compliance, quality of life, specific adverse effects and disease severity scores, and mortality. MAIN RESULTS: Three trials have been identified as being suitable for inclusion in the review and we are awaiting further data from one of these trials. All of these trials were carried out in children with cystic fibrosis. Few statistical differences could be found between the treatment and control groups apart from change in total fat intake at three months (weighted mean difference 69.20 [95% CI 11.05, 127.35]). However, this was based on the results of only one, small study. No trials have been identified which assess the effectiveness of oral protein calorie supplements in children with other chronic diseases. REVIEWER'S CONCLUSIONS: Oral protein calorie supplements are widely used to improve the nutritional status of children with a number of chronic diseases. We have only been able to identify a small number of trials assessing these products in children with cystic fibrosis and have been unable to draw any conclusions based on the limited data extracted from these. We therefore recommend that a series of large, randomised controlled trials are undertaken investigating the use of these products in children with different chronic diseases. Until further data are available, we would suggest that these products are only used with caution.

Adolescent↗
PubMed2000

Intestinal inflammation in cystic fibrosis.

BACKGROUND: There is controversy about whether the inflammatory response observed in the cystic fibrosis (CF) lung occurs secondary to bacterial infection or is caused by a dysregulation of the inflammatory response associated with the basic cellular defect of CF. AIMS: To study the inflammatory response in the gastrointestinal tract of children with CF; and to investigate whether there is increased inflammation in the gastrointestinal tract of CF children with fibrosing colonopathy. METHODS: Whole gut lavage was performed on 21 pancreatic insufficient children with CF, who were clinically well, five children with CF and fibrosing colonopathy, and 12 controls. Intestinal outputs of plasma derived proteins (albumin, alpha(1) antitrypsin, IgG), secretory immunoglobulins (IgA and IgM), cellular constituents (eosinophil cationic protein and neutrophil elastase), and cytokines (interleukin 8 and interleukin 1beta) were measured. RESULTS: Compared to controls, the 21 CF patients, with no intestinal complications, had increased intestinal outputs of albumin, IgG, IgM, eosinophil cationic protein, neutrophil elastase, interleukin 1beta, and interleukin 8. Similar values were obtained for the CF patients with fibrosing colonopathy. CONCLUSIONS: These data suggest that there is immune activation in the gastrointestinal mucosa of children with cystic fibrosis, which may result from the basic cellular defect. Fibrosing colonopathy does not appear to be associated with increased inflammation.

Adolescent↗
PubMed2000

Reliability of percentage ideal weight for height.

AIMS: To assess the reliability of percentage ideal weight for height (%WFH) as a measure in children. METHODS: Forty two dietitians calculated %WFH of six children. Eleven of the 42 repeated the calculations. RESULTS: Interexaminer estimates varied by 16.5 to 40 percentage points (mean 27.8). Intraexaminer variability was also large. CONCLUSIONS: %WFH is an unreliable measure of nutritional status.

Body Height↗
PubMed2000

The current management of cystic fibrosis.

Cystic fibrosis (CF) is one of the commonest lethal inherited conditions among Caucasians. It affects multiple organ systems and exhibits a range of clinical problems of varying severity. Life expectancy has improved in recent years as treatment regimes have become more intensive, but current treatments are expensive, often time consuming and may affect quality of life. This review summarises the treatments currently used in the management of patients with CF, and the evidence for these.

Anti-Bacterial Agents↗
PubMed1998

Evidence-based pediatric pulmonary medicine: how can it help?

Evidence-based medicine aims to identify, critically appraise, and apply the best available evidence in making decisions about the care of patients. These aims are similar to those conscientious clinicians have always sought to achieve, but an evidence-based approach applies a systematic and rigorous methodology to this process to ensure that the evidence applied is relevant and of high quality. Because of the volume of potentially relevant information that needs to be accessed from the medical literature, many clinicians rely on reviews of the evidence. Systematic reviews provide summaries of the results of evidence-based healthcare, which can be made available to clinicians, healthcare administrators, and patients. The use of explicit, systematic methods in reviews limits bias (systematic errors) and reduces random errors (simple mistakes), thus providing reliable results on which to draw conclusions and make decisions. Meta-analysis is the use of statistical methods to summarize the results of independent studies. When used appropriately, meta-analysis can provide more precise estimates of the effects of healthcare than those derived from the individual studies included in a review. Childhood respiratory diseases can be a challenging area in which to undertake clinical research. These challenges include diagnostic uncertainty, lack of objective endpoints, and aspects of generalizability of randomized controlled trials. Despite these difficulties, there are now many examples of systematic reviews and evidence-based approaches in pediatric pulmonology. If applied appropriately, they can ensure that management of patients is based on clinically useful diagnostic tests and treatments that have been shown to be effective and not harmful.

Child↗
PubMed1998

Time to publication as full reports of abstracts of randomized controlled trials in cystic fibrosis.

OBJECTIVES: To determine 1) what proportion of abstracts of randomized controlled trials (RCTs) presented at international conferences on cystic fibrosis (CF) are published as full reports, 2) time to publication, and 3) factors that might delay or prevent publication. METHODS: At the end of 1995, the Cochrane CF Group's register of RCTs contained 199 abstracts describing 180 RCTs. Abstracts were identified by handsearching 44 abstract books of three international CF conferences over a 30-year period. We searched the register for subsequent full reports of these RCTs and used survival analysis to investigate time to publication. Using the log-rank test, we examined 1) whether there is a difference in time to publication between reports where the investigators concluded that the test treatment was as effective as or better than the control treatment, and reports where it was not, and 2) whether there is a difference in time to publication according to sample size. RESULTS: Thirty-two percent of the 178 abstracts analyzed were subsequently published in full. Survival analysis indicated that the proportions published before 12 months, 2 years, and 5 years were 8.1%, 29%, and 40% respectively. No difference in time to publication was identified when the abstracts were stratified according to conclusions or sample size; no significant association (P > 0.05) existed between time to publication and both sample size and conclusions together. CONCLUSION: Only a small proportion of abstracts of RCTs presented at international conferences on CF are followed by full publication, and usually only after several years. Therefore, many potentially valuable studies do not reach a wide audience. However, we found no consistent factors which might delay or prevent publication.

Abstracting and Indexing↗
PubMed1997

Immunological responses to respiratory syncytial virus infection in infancy.

OBJECTIVES: To determine whether there is evidence of immunological responses in infants with respiratory syncytial virus (RSV) bronchiolitis by measuring inflammatory mediators in peripheral blood and, if found, whether these related to the severity of illness. PATIENTS AND METHODS: Blood was taken from 94 children with RSV infection during the acute episode and 10 or more days later when the child was well. Control serum samples were obtained from well children of similar ages. Serum samples were assayed for mediators of lymphocyte activity (interleukin-4 (IL-4), soluble interleukin-2 receptor (sCD25), soluble intercellular adhesion molecule-1 (sICAM-1), eosinophil activity (eosinophil cationic protein) and neutrophil activity (myeloperoxidase). Symptoms were assessed as very mild (coryza only), mild (symptoms of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: IL-4 concentrations were at the lower limits of detection of the assay. The concentrations of sCD-25 were greater in samples from patients with acute illness than from convalescent patients and both were greater than in control samples. sICAM-1 concentrations were similar in samples from patients with acute illness and convalescent patients, but both were greater than in samples from controls. Eosinophil cationic protein concentrations were lower in samples from patients with acute illness than in those from convalescent patients; there was no difference between samples from convalescent and control patients. Myeloperoxidase concentrations were similar in all samples. There was no correlation between the severity of infection and the concentrations of any inflammatory mediators. CONCLUSIONS: There is evidence of an inflammatory response in the peripheral blood of infants with acute bronchiolitis which may affect lymphocytes and eosinophils, but an association between this response and the severity of illness was not shown here.

Acute Disease↗
PubMed1997

Enhanced drug metabolism in young children with cystic fibrosis.

The effect of cystic fibrosis on caffeine metabolism was studied in young children using the caffeine breath test. Eight children with cystic fibrosis aged 2-6 years and nine age matched controls were studied on a single occasion, and the cumulative percentage of labelled caffeine exhaled as carbon dioxide measured over two hours. This was significantly higher in the patients with cystic fibrosis than in controls, suggesting an increase in the CYP1A2 metabolic pathway in the former. The fact that these were young children with minimal lung and liver disease suggests that enhanced drug metabolism in children with cystic fibrosis is hereditary rather than secondary to lung and liver damage.

Breath Tests↗
PubMed1997

Respiratory syncytial virus genotypes and disease severity among children in hospital.

OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease.

Acute Disease↗