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Biomedical subjects

C Deaton

Publications and source records attributed to C Deaton.

18 recordsLinked to original sources
PubMed2002

Heart size estimated by echocardiography correlates with maximal oxygen uptake.

Maximum oxygen uptake also appears to correlate to athletic performance in horses. In the Thoroughbred industry, there has long been an empirical theory that heart size is related to athletic performance, despite a lack of scientific evidence supporting this assertion. To investigate the relationship between peak oxygen consumption (VO2max) and cardiac size measured by echocardiography, guided M-mode and 2-dimensional echocardiography were performed in 17 conditioned Thoroughbreds with a range of VO2max from 126 to 217 ml/min/kg STPD (mean +/- s.d. 158 +/- 28 m/min/kg). Horses were age 2-10 years and weighed 430-510 kg. Echocardiography was performed using a Vingmed System V echocardiograph with a 2.25 MHz phased array ultrasound transducer. All images were obtained from the right hemithorax using a short axis view of the left ventricle (LV) at the level of the chordae tendinae. All horses were free from significant regurgitation at the aortic or mitral valves. Maximal oxygen uptake was measured during a standardised incremental treadmill exercise test to fatigue. Maximal oxygen uptake was correlated significantly with LVIDd (r = 0.71; P = 0.001), MWT (r = 0.72; P = 0.001), LV mass (r = 0.78; P = 0.0002) and LV short-axis area (r = 0.69; P = 0.003). When indices of heart size were indexed to bodyweight, the correlation between VO2max and indices of heart size were LVIDd (r = 0.57; P = 0.01), MWT (r = 0.44; P = 0.07), LV mass (r = 0.78; P = 0.0002) and LV short-axis area (r = 0.69; P = 0.003). The current study suggests there is a strong relationship between VO2max and measurements of left ventricular size in Thoroughbred horses when individuals with a range of VO2max are compared.

Animals↗
PubMed2001

Environmental enrichment decreases intravenous self-administration of amphetamine in female and male rats.

RATIONALE: Previous work has shown that environmental enrichment alters amphetamine-induced locomotor activity and conditioned place preference. OBJECTIVE: The present study examined the effect of environmental enrichment on amphetamine self-administration. METHODS: Female and male rats were raised from 21 days of age in one of three different conditions: an enriched condition (EC) containing novel objects and social partners, a social condition (SC) containing social partners only, or an isolated conditioned (IC) without objects or social partners. Beginning at 51 days of age, rats were then tested for operant responding for a sucrose reinforcer using an incremental fixed ratio (FR) requirement across four sessions. Rats were then implanted with a chronic indwelling intravenous catheter and were allowed to self-administer amphetamine (0.03 or 0.1 mg/kg per infusion) for five FR1 sessions, followed by a progressive ratio (PR) session. RESULTS: EC rats initially showed an increase in sucrose-reinforced responding relative to IC rats and this environment-induced difference was greater in females than in males. However, in both sexes, the environment-induced difference in sucrose-reinforced responding dissipated completely across repeated sessions. With amphetamine self-administration, both EC and SC rats earned fewer infusions than IC rats across repeated FRI sessions using the low dose of amphetamine (0.03 mg/kg per infusion), but not using the higher dose of amphetamine (0.1 mg/kg per infusion). EC rats also earned fewer self-infusions of the low amphetamine dose on the PR session relative to IC rats. The effects of environmental enrichment on amphetamine self-administration were similar in both females and males. CONCLUSION: These results suggest that environmental enrichment may serve as a protective factor for reducing amphetamine self-administration.

Amphetamine↗
PubMed2001

A collaborative program for cardiovascular patient follow-up.

Transitions from one health care system to another are common, but they can affect coordination of care and measurement of patient outcomes. In this project, a community hospital and a tertiary center collaborated to obtain follow-up information on patients 30 days after they underwent cardiac catheterization and revascularization. Results show that patients experienced similar physical and emotional concerns regardless of diagnosis or procedure. Although the intent was to gather information, nurses also provided education and arranged services for patients. This project has implications for the development of collaborative interventions to improve care for patients after undergoing coronary procedures.

Aftercare↗
PubMed2001

Outcomes measurement and evidence-based nursing practice.

Outcome measurement and evidence-based practice are complementary and iterative efforts; both contribute to quality health care. In this article, hemodynamic monitoring is utilized as an example to discuss outcome measurement and evidence-based practice. The use of technology, medications, and other interventions ideally would be based on sound scientific evidence of efficacy and effectiveness in clinical practice. Outcome measurement can contribute to the evidence and strengthen the process of appropriate technology use and evidence-based practice.

Evidence-Based Medicine↗
PubMed2001

Diagnostic strategies for women with suspected coronary artery disease.

The clinician evaluating a woman with symptoms potentially indicative of coronary heart disease faces the challenge of choosing the appropriate diagnostic test. The use of noninvasive testing in women has been controversial due to a perception of diminished accuracy, limited female representation, and technical limitations that compromise efficacy. Recent meta-analyses and large observational series report marked improvements in accuracy for women undergoing exercise treadmill, echocardiography, and nuclear testing. Electron beam computed tomography is a relatively new technique, and the body of evidence is still developing. An adequate body of evidence supports the use of noninvasive testing for intermediate risk, symptomatic women and may result in improved diagnostic and therapeutic decision making.

Coronary Artery Disease↗
PubMed2001

Predictors and outcomes associated with early extubation in older adults undergoing coronary artery bypass surgery.

BACKGROUND: Older age has been associated with prolonged mechanical ventilation after coronary artery bypass surgery. Prolonged mechanical ventilation contributes to increased morbidity and mortality and to use of limited financial resources among older adults. OBJECTIVES: To examine selected physiological and pathophysiological variables ofpresurgicalpatients to predict duration of mechanical ventilation in older adults after coronary artery bypass surgery. METHODS: Nonrandomized study of a clinical database of 919 patients (> or =65 years old) who had coronary artery bypass surgery between October 1996 and December 1997. RESULTS: Median elapsed time after coronary artery bypass surgery until extubation was used to sort patients into 2 groups: group 1, 6 hours or fewer (n = 464); and group 2, more than 6 hours (n = 455). With stepwise logistic regression, the physiological model included age (odds ratio, 1.05; P<.001) and female sex (odds ratio, 1.48; P = .005) with weak discrimination by group (concordance statistic = 0.5880). The pathophysiological model, which included renal insufficiency (odds ratio, 3.28; P = .01), previous peripheral vascular surgery (odds ratio, 2.87; P = .03), nonelective preoperative clinical status (odds ratio, 2.8; P = .006), congestive heartfailure (odds ratio, 2.6; P<.001), and reoperation (odds ratio, 2.34; P = .007), showed moderate discrimination bygroup (concordance statistic =0.6755). CONCLUSION: Many older adults were easily extubated and had good outcomes. The variables comorbid conditions and severity of illness provided better discrimination between extubation groups than a physiological model provided. Both predictive models allowed limited discrimination between groups.

Aged↗
PubMed2000

Ethnicity and analgesic practice.

STUDY OBJECTIVE: We previously reported that Hispanic ethnicity was an independent risk factor for inadequate analgesic administration among patients presenting to a single emergency department. We then attempted to generalize these findings to other ethnic groups and EDs. Our current study objective is to determine whether black patients with extremity fractures are less likely to receive ED analgesics than similarly injured white patients. METHODS: We conducted the following retrospective cohort study at an urban ED in Atlanta, GA. All black and white patients presenting with new, isolated long-bone fractures over a 40-month period were studied. After abstracting demographic information from the medical record and subsequently removing ethnic identifiers, we submitted the medical record to a physician who recorded characteristics of the patients' injury and treatment. We then submitted the records to a nurse, again blinded to ethnicity, who recorded analgesic administration. We used multiple logistic regression to determine the independent effect of ethnicity on analgesic use while controlling for multiple potential confounders. Our main outcome measure was the proportion of black versus white patients receiving ED analgesics. RESULTS: The study group consisted of 217 patients, of whom 127 were black and 90 were white. White patients were significantly more likely than black patients to receive ED analgesics (74% versus 57%, P =.01) despite similar records of pain complaints in the medical record. The risk of receiving no analgesic while in the ED was 66% greater for black patients than for white patients (relative risk 1.66, 95% confidence interval, 1.11 to 2.50). This effect persisted after controlling for multiple potential confounders. CONCLUSION: Black patients with isolated long-bone fractures were less likely than white patients to receive analgesics in this ED. No covariate measured in this study could account for this effect. Our findings have implications for efforts to improve analgesic practices for all patients.

Adult↗
PubMed2000

Outcome measurement: self-management in heart failure.

Improvement in heart failure outcomes depend on patients' abilities to care for themselves and manage aspects of their condition, and patient self-management has itself become an outcome to be measured. Some behaviors, such as diet and fluid restriction, are prescribed, and self-management is often equated with adherence to the treatment regimen. Self-management has also been defined as cognitive decision making in response to symptoms and conceptualized as a process with stages from novice to expert. Greater understanding and measurement of patient decision making and self-management expertise facilitates the development of effective interventions to improve patient outcomes.

Health Behavior↗
PubMed1999

Can cardiovascular clinical characteristics be identified and outcome models be developed from an in-patient claims database?

The objective of this study was to assess whether administrative (claims) databases can be used to assess clinical variables and predict outcome. Although administrative databases are useful for assessing resource utilization, their utility for assessing clinical information is less certain. Prospectively gathered clinical databases, however, are expensive and not widely available. The UB92 formulation of the hospital bill was used as an administrative source of data and compared with the clinical cardiovascular database at Emory University. The claims database was compared with the clinical database for 11 variables. Outcome models were developed with multivariate methods. A total of 11,883 patients who underwent catheterization (5,255 underwent percutaneous transluminal coronary angioplasty [PTCA] and 3,794 underwent coronary artery bypass surgery [CABG]) between 1991 and 1995 were included. For some variables, the claims database correlated well (diabetes, sensitivity 87%, specificity 99%), whereas for others the claims database was less accurate (peripheral vascular disease, sensitivity 20%, specificity 99%). Uncertain coding in the claims database, which can result in the same code being used for co-morbid states and severity of disease, as well as complications, limited the ability of claims to predict outcome. Clinical databases may also be limited by lack of objectivity and missing data. The utility of claims databases to assess severity of disease and co-morbid states is limited, and outcome modeling and risk assessment from claims databases may be inappropriate and spurious. Developing better data standards and less expensive methods for acquisition of clinical data is necessary for improved outcome assessment.

Cardiovascular Diseases↗
PubMed1999

Outcomes measurement.

Reductions in hospital lengths of stay (LOS) for patients with cardiovascular conditions can be a cost-effective in-hospital outcome, but the effect of shortened hospital LOS on patient and family outcomes after discharge needs to be evaluated. Suggestions for the use of appropriate data to evaluate LOS and outcomes that need study are presented.

Cardiovascular Diseases↗
PubMed1999

The effect of primary care gatekeepers on the management of patients with chest pain.

OBJECTIVE: To determine whether patients with chest pain referred to a cardiologist from a gatekeeper managed care organization differ from those referred from an open-access managed care organization. STUDY DESIGN: Retrospective study using clinical and claims data from a cardiac network database. PATIENTS AND METHODS: We reviewed data from 1414 patients with chest pain or angina who were referred to a cardiologist between January 1, 1995, and June 30, 1996. We examined baseline clinical characteristics and subsequent physician practice patterns for these patients, who were referred from either a primary care gatekeeper model (n = 490) or an open-access model (n = 924). RESULTS: Although twice as many open-access patients were referred to a cardiologist, there were no differences in patient demographics or clinical characteristics at the time of referral. Cardiologists ordered similar diagnostic tests for patients from both types of managed care plans, and gatekeeper patients did not have a higher rate of abnormal tests. Rates of cardiac catheterization, coronary angioplasty, myocardial infarction, and hospitalization were similar in both groups. A significantly higher percentage of gatekeeper patients received a cardiac catheterization on the day of referral (7% versus 1%; P = .05). Open-access patients were significantly more likely to continue to be seen by a cardiologist (44% versus 28%; P < .01). Cardiology professional charges per patient were lower among gatekeeper patients ($972 +/- 1398 versus $1187 +/- 1897; P = .06), and total cardiology professional charges were significantly lower for the gatekeeper group because of the smaller number of patients seen. CONCLUSIONS: The type of cardiology services provided to patients with chest pain was not affected by the primary care administrative structure of the managed care organization, but the higher volume of patient referrals from the open-access plan may be an important consideration for cardiology practices participating in capitated contracts. The lower volume of referrals and coordination of care suggest potential cost advantages for the gatekeeper model.

Adult↗
PubMed1998

Improving cost and outcome of coronary surgery.

BACKGROUND: There has been increasing interest in improving the outcome of coronary surgery while also seeking to minimize cost. It was the purpose of the present study to determine changes in the outcome and cost of CABG between 1988 and 1996. METHODS AND RESULTS: The outcome and costs for 12,266 patients undergoing CABG were evaluated. Clinical data were gathered from the Emory Cardiovascular Database, and financial data were obtained from the UB92 formulation of the hospital bill. Charges were reduced to cost through the use of departmental cost-to-charge ratios. Costs were inflated to 1996 costs by using the medical care inflation rate. The patients became sicker, especially with increased incidences of hypertension, diabetes, and prior myocardial infarctions and a decrease in ejection fraction over the study period. Mortality rates tended to decrease from 4.7% to 2.7% (P = 0.07). After accounting for increasing indexes of severity of disease over the period, there was a significant decrease in death (OR, 0.90/y; P = 0.0001). Q-wave myocardial infarction rate fell from 4.1% to 1.3% (P < 0.0001). Mean hospital cost decreased from $22,689 to $15,987. Length of stay after surgery decreased from 9.2 to 5.9 days. After accounting for other variables, cost decreased by $1118 per year, and annual length of stay decreased by 0.55 day. CONCLUSIONS: The outcome of CABG continues to improve with declines in mortality rate and Q-wave myocardial infarction. This was accomplished while decreasing costs and length of stay. Whether these favorable trends will continue remains to be seen.

Aged↗
PubMed1998

Outcomes measurement.

Patient outcomes have been referred to as the "ultimate definition of effectiveness and efficiency," and there is an increasing emphasis on identifying and measuring the results of interventions and practice. This new department will focus on issues surrounding patient outcomes such as definitions, measurement, sources of data, nurse-sensitive versus multidisciplinary outcomes, and determining the evidence on which to base practice. The goal of the department is to stimulate questions and encourage discussion that will contribute to the necessary knowledge for defining, measuring, and ultimately improving cardiovascular patient outcomes.

Cardiovascular Surgical Procedures↗
PubMed1998

Patient perceived health status, hospital length of stay, and readmission after coronary artery bypass surgery.

This study evaluates the effect of length of stay and baseline health status on health status and readmission rates 3 months after coronary artery bypass graft surgery. Baseline health status showed a trend toward worse scores for patients who were readmitted. Readmitted patients had longer lengths of stay, and worse 3-month health status scores, and women and patients with heart failure had higher readmission rates. It may be possible to identify patients at risk for readmission using clinical variables, length of stay, and health status. If a predictive model can be developed, then interventions can be developed and tested to decrease the rate of unplanned readmissions.

Adult↗
PubMed1998

Outcomes measurement. Multidisciplinary approaches and patient outcomes after stroke.

Synergism is an apt description for the powerful results that can occur when multidisciplinary approaches are used. Studies have documented that multidisciplinary teams produce improved patient outcomes in selected patient groups, including recent studies of patients with strokes. Multidisciplinary teams in patient care are still far from being the normative model of care delivery. In the interest of better patient care and outcomes, it is time for health care professionals to actively engage in multidisciplinary approaches, because the sum of our collaborative efforts is greater than our individual disciplinary parts.

Cerebrovascular Disorders↗
PubMed1998

Heart failure: strategies to enhance patient self-management.

Successful management of heart failure requires an active partnership between the patient and health care providers. This can be facilitated through a focused patient education plan that begins in acute care and has continuity into the community. Elements of the education plan involve both teaching content areas and self-management behaviors. Clinical pathways for heart failure incorporate teaching and educational strategies to guide the work of the multidisciplinary team, and the advanced practice nurse has tremendous potential in facilitating improved patient outcomes.

Activities of Daily Living↗
PubMed1982

Light scattering and its application for the clinical laboratory.

Nephelometric systems have enabled precise and rapid quantitation of specific proteins, therapeutic drugs, and other compounds. This paper begins with a discussion of the physics of light scatter and then explores various turbidimetric and nephelometric systems that employ light scatter. A detailed discussion of manual and automated nephelometer-based systems is offered.

Light↗