Search PubMed⌕ Search

Biomedical subjects

G Cunningham

Publications and source records attributed to G Cunningham.

At least 37 records · Page 2Linked to original sources
PubMed1998

Yohimbine in neurally mediated syncope. Pathophysiological implications.

In this study, we evaluated if increased sympathetic stimulation is an essential requirement for the development of neurally mediated syncope (NMS) by manipulating overall sympathetic outflow in subjects susceptible to tilt-induced syncope. Eight previously characterized patients with recurrent NMS (five females and three males; 34+/-2 yr) were recruited from the Vanderbilt Syncope Unit and eight age-matched controls underwent initial administration of clonidine (CLO) or yohimbine (YHO). This was done, prospectively, to determine doses of these agents that would increase or decrease plasma norepinephrine levels by >/= 30%. On a different day, in all subjects we determined intraarterial blood pressure, EKG and muscle sympathetic nerve activity (MSNA) both supine and during upright tilt. After this, subjects randomly received either CLO or YHO, and 3 h later another tilt was performed. After 1 wk, a similar procedure with the other drug was performed. During the two basal tilts, all the control subjects completed the study, whereas all the NMS patients developed syncope. Reduction in sympathetic tone by CLO resulted in a decreased tolerance to tilt in three out of eight controls and in all the NMS patients. In contrast, YHO not only increased basal plasma NorEpi levels and MSNA, but also prevented syncope in seven out of eight patients. In a selected population of patients, increased sympathetic activity is not a prerequisite for the development of syncope. Yohimbine-induced enhancement of sympathetic tone in patients with NMS improves orthostatic tolerance and raises the possibility that this drug may be a useful agent in the treatment of NMS.

Adult↗
PubMed1997

Drug-related problems in elderly patients admitted to Tayside hospitals, methods for prevention and subsequent reassessment.

INTRODUCTION: although drug-related problems (DRPs) are known to be prevalent in elderly patients, the literature on prevention of iatrogenic disease is sparse. The present study addresses this requirement. OBJECTIVES: to assess the incidence of DRPs in elderly patients admitted to Tayside hospitals before (phase I) and after (phase II) implementation of preventive strategies. DESIGN: all elderly people admitted to hospital were screened by a pharmacist; individual case reviews were prepared for all those with a potential DRP and reviewed by a three-member panel which made a final decision on the presence of a DRP and its contribution to admission. SETTING: all hospital wards admitting elderly patients in the Tayside region of Scotland. SUBJECTS: 1011 elderly patient admissions over a 9-month period (phase I); 857 elderly patient admissions over an 8-month period (phase II). MAIN OUTCOME MEASURES: incidence of DRPs before and after targeted intervention strategies (information bulletin for general practitioners, patient information leaflet, oral presentation to trainee general practitioners). RESULTS: in phase I, the incidence of DRPs was 144/1011 (14.2%), with 54/1011 (5.3%) of the admissions identified as being definitely or probably drug-related. Non-steroidal anti-inflammatory drugs (NSAIDs) were the main drug group involved, being responsible for 15/54 (28%) of admissions primarily due to a DRP. Over 66% of admissions due to adverse effects of NSAIDs were considered to be definitely preventable. In phase II, after targeted intervention strategies, there was no significant reduction in total incidence of DRPs or incidence of DRPs related to NSAIDs. However, there appeared to be an improvement in the first 4 months, and a significant drop in NSAID prescribing in Tayside compared with the rest of Scotland was observed. CONCLUSION: DRPs remain a significant problem in elderly patients and NSAIDs are the major contributor. The intervention strategies used in the study were not demonstrably effective, but a continuous programme of education may be necessary to limit NSAID use.

Aged↗
PubMed1997

Adverse drug reactions in the elderly and their prevention.

Increasing age is often associated with multiple medical problems and therefore, the potential for increasing amounts of prescribed medication. Adverse reactions are a recognised hazard of drug therapy in elderly patients due to the amount of medication prescribed and the greater susceptibility of older people to adverse reactions. The problem is unlikely to diminish in the near future due to the proportionately increasing ageing population. Prevention of adverse drug reactions in the elderly deserves closer attention.

Aged↗
PubMed1995

Fetal karyotyping for chromosome abnormalities after an unexplained elevated maternal serum alpha-fetoprotein screening.

OBJECTIVE: To study the chromosome abnormality rate among women with elevated levels of maternal serum alpha-fetoprotein (MSAFP) and the types of chromosome abnormalities in this population, and to compare this rate with reports in the literature and the rate observed in the general population. METHODS: We studied 8097 women who chose to undergo amniocentesis and fetal karyotyping after having an elevated MSAFP test of 2.5 multiples of the median (MOM) or higher. All abnormal karyotypes were reviewed and grouped according to whether the elevated MSAFP value could be explained by a ventral wall or neural tube defect. RESULTS: The overall chromosome abnormality rate was 13.83 per 1000 amniocenteses. The rate in the "unexplained" group was 10.92 per 1000 amniocenteses. Just over half (53%) of the abnormal karyotypes were autosomal anomalies, and 47% were sex chromosome abnormalities. The autosomal aneuploidies observed most frequently were triploidy and trisomy 13. The sex chromosome abnormalities observed most frequently were the XXY and XYY karyotypes. CONCLUSION: Women who have unexplained elevated MSAFP values of 2.5 MOM or greater have a twofold increase in the rate of chromosome abnormalities in their fetuses compared with the general population (P < or = .001). This rate is consistent with other studies that used a 2.5 MOM cutoff. Studies that used a 2.0 MOM cutoff have reported chromosome abnormality rates that do not vary from general population estimates.

Adult↗
PubMed1995

Assessment of anxiety in hospital patients.

There has been research in North America to validate the nursing diagnosis of anxiety. As part of this work, Young used the defining characteristics and developed a tool to measure anxiety. The present research sought to extend that study in the United Kingdom, assess the anxiety-defining characteristics tool and identify key indicators of anxiety that might be useful in clinical practice. Four anxiety measurement tools, drawn from the literature, were used. These were the state trait anxiety inventory, the graphic anxiety scale, the hospital anxiety and depression scale, and the anxiety-defining characteristics tool. A random sample of 79 hospitalized patients were interviewed and their anxiety rated using all four measures. Calculation of Spearman's correlation co-efficients revealed convergent validity between the anxiety-defining characteristics tool and the state trait anxiety inventory and the anxiety score on the hospital anxiety and depression scale. Anxiety levels were found not to be affected by the age or sex of the respondent, or the length of stay or number of previous admissions. Discriminant analysis suggested that six characteristics adequately discriminated anxious subjects: sweating, faintness, tendency to blame others, continual review of things in their mind, focus on self and a lack of self-confidence. The study concluded that there is a scope for further research into these characteristics and their use in clinical practice.

Adult↗
PubMed1994

Universal screening for hemoglobinopathies using high-performance liquid chromatography: clinical results of 2.2 million screens.

In screening for hemoglobinopathies, high-performance liquid chromatography (HPLC) achieves excellent sensitivity and specificity, while adding the very important quantitative element to the analysis. Due to the development of a rapid, automated HPLC system, California began screening 600,000 births per year in 1990 using this method. Based on confirmatory testing for 97% of the initial positive results resulting from 2.2 million screens, HPLC has proven to be clinically accurate. In conjunction with the availability of quantitative data, HPLC provides a complete screening system, eliminating the need for a second screening test, and accurately discriminating beta thalassemia compound conditions. The large degree of ethnic diversity and high birth rate in California have produced detailed and reliable birth prevalence rates for most conditions and ethnicities.

Blood↗
PubMed1990

Risk of neural tube defects in relation to maternal fertility and fertility drug use.

In a case-control study to investigate whether women who use drugs to induce ovulation are at increased risk of conception of a child with a neural tube defect, 571 women who had a fetus or child with a neural tube defect, 546 women who had a fetus or child with other abnormalities, and 573 women who had an apparently normal fetus or child were questioned about infertility, fertility drug use, and related obstetric problems. The rate of maternal fertility drug use around the time of conception was not significantly higher for neural tube defects than for other abnormalities (odds ratio 1.28; 95% confidence interval 0.39, 4.51) or no abnormalities (odds ratio 0.80; 95% Cl 0.27, 2.27). Fertility drug use at any time was not significantly more frequent for neural tube defects than for other abnormalities (odds ratio 1.37; 95% Cl 0.70, 2.74) or no abnormalities (odds ratio 1.05; 95% Cl 0.56, 1.98).

Abnormalities, Drug-Induced↗