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Robert Phillips

Publications and source records attributed to Robert Phillips.

11 recordsLinked to original sources
PubMed2006

Carbogen and nicotinamide increase blood flow and 5-fluorouracil delivery but not 5-fluorouracil retention in colorectal cancer metastases in patients.

PURPOSE: To examine whether carbogen and nicotinamide increases 5-fluorouracil (5-FU) delivery to colorectal cancer metastases. EXPERIMENTAL DESIGN: Six patients were scanned using positron emission tomography. Two scans were done to coincide with the start of separate chemotherapy cycles. At the second positron emission tomography session, 60 mg/kg nicotinamide was given orally 2 to 3 hours before 10-minute carbogen inhalation. In the middle of carbogen treatment, [15O]H2O (to measure regional tissue perfusion) and then [18F]5-FU (to measure 5-FU tissue pharmacokinetics) were administered. RESULTS: Regions of interest were drawn in 12 liver metastases, 6 spleens, 6 livers, and 12 kidneys. Nicotinamide and carbogen administration increased mean blood pO2 from 93 mm Hg (95% confidence interval, 79-198) to 278 mm Hg (95% confidence interval, 241-316; P = 0.031). Regional perfusion (mL(blood)/min/mL(tissue)) increased in metastases (mean change = 52%, range -32% to +261%, P = 0.024), but decreased in kidney (mean change = -42%, range -82% to -11%, P = 0.0005) and liver (mean change = -34%, range -43% to -26%, P = 0.031). 5-FU uptake at 3.75 minutes (m(2)/mL) increased in tumor (mean change = 40%, range -39% to +196%, P = 0.06) and decreased in kidney (mean change = -25%, range -71% to 12%, P = 0.043). 5-FU delivery measured as K1 increased in tumor (mean change = 74%, range -23% to +293%, P = 0.0039). No differences were seen in [18F]5-FU tumor exposure (net area under curve) and retention. CONCLUSION: Nicotinamide and carbogen administration can increase 5-FU delivery to colorectal cancer liver metastases. Despite an increase in perfusion and 5-FU delivery, the effects were not directly related and did not increase 5-FU retention or tissue exposure.

Administration, Inhalation↗
PubMed2003

Medicine as a performing art: a worthy metaphor.

PURPOSE: Despite numerous calls for reform over several decades, medical educators have been unable to address many significant challenges. Potentially, employing new metaphors and looking at the teaching and learning of medicine in a new way will facilitate the development of creative solutions. MAIN FINDINGS: In this paper we propose the metaphor of medicine as a performing art. Building on this metaphor, string music education is compared to medical education. PRINCIPAL CONCLUSIONS: Looking to string education as a model, suggestions for reorganisation of learning experiences, academic structure and assessment are discussed. Medical educators are encouraged to think about the challenges they face in creative ways. By looking outside traditional medical education, solutions may be found to new and old educational dilemmas.

Clinical Competence↗
PubMed2003

The ecology of medical care for children in the United States.

BACKGROUND: Medical care ecology has previously been investigated for adults, but no similar exploration has been made specifically for children. OBJECTIVE: To describe proportions of children receiving care in 6 types of health care setting on a monthly basis and to identify characteristics associated with receipt of care in these settings. METHODS: Nationally representative data from the 1996 Medical Expenditure Panel Survey were used to estimate the number of children per 1000 per month who received care at least once in each type of setting. Multivariate analyses assessed associations between receiving care in various settings and children's sociodemographic factors (age, sex, ethnicity, poverty, parent's education, urban or rural residence, insurance status, and whether or not the child had a usual source of care). RESULTS: Of 1000 children aged 0 to 17 years, on average each month 167 visited a physician's office, 82 a dentist's office, 13 an emergency department, and 8 a hospital-based outpatient clinic. Three were hospitalized and 2 received professional health care in their home. Younger age was associated with increased proportions of children receiving care in all health care settings except dentists' clinics. Poverty, lack of health insurance, black race, and Hispanic ethnicity were associated with decreased receipt of care in physicians' and dentists' offices. Only age (<2 years and 13-17 years) and poverty status were associated with hospitalization (P <.05 for each). Rural residence was not associated with any significant variation in proportions of children receiving care in any setting. Having a usual source of care was associated with increased receipt of care in all settings except hospitals. CONCLUSIONS: The ecology of children's medical care is similar to that of adults in the United States in that a substantial proportion of children receive health care each month, mostly in community-based, outpatient settings. In all settings except emergency departments, receipt of care varies significantly by children's age, race, ethnicity, income, health insurance status, and whether they have a usual source of care.

Adolescent↗
PubMed2003

Receipt of preventive care among adults: insurance status and usual source of care.

OBJECTIVES: This study ascertained the separate and combined effects of having insurance and a usual source of care on receiving preventive services. METHODS: Descriptive and multivariate analyses of 1996 Medical Expenditure Panel Survey data were conducted. RESULTS: Receipt of preventive services was strongly associated with insurance and a usual source of care. Significant differences were found between insured adults with a usual source of care, who were most likely to have received services, compared with uninsured adults without regular care, who were least likely to have received services. Those with either a usual source of care or insurance had intermediate levels of preventive services. CONCLUSIONS: Having a usual source of care and health insurance are both important to achieving national prevention goals.

Adolescent↗
PubMed2002

Ethnic differences in electrocardiographic criteria for left ventricular hypertrophy: the LIFE study. Losartan Intervention For Endpoint.

BACKGROUND: African Americans have greater precordial QRS voltages than whites, with concomitant higher prevalences of electrocardiographic (ECG) left ventricular hypertrophy (LVH) and lower specificity of ECG LVH criteria for the identification of anatomic hypertrophy. However, the high mortality associated with LVH in African American patients makes more accurate ECG detection of LVH in these patients a clinical priority. METHODS: Electrocardiograms and echocardiograms were obtained at study baseline in 120 African American and 751 white hypertensive patients enrolled in the Losartan Intervention For Endpoint (LIFE) echocardiographic substudy. The ECG LVH was determined using Sokolow-Lyon, 12-lead sum, and Cornell voltage criteria. Echocardiographic LVH was defined by LV mass indexed to height(2.7) >46.7 g/m(2.7) in women and >49.1 g/m(2.7) in men. RESULTS: After adjusting for ethnic differences in LV mass, body mass index, sex, and prevalence of diabetes, mean Sokolow-Lyon and 12-lead sum of voltage were significantly higher, but Cornell voltage was lower, in African Americans than in whites. As a consequence of these differences, when identical partition values were used in both ethnic groups, Sokolow-Lyon and 12-lead voltage criteria had lower specificity in African Americans than whites (44% v 69%, P = .007 and 44% v 59%, P = .10) but had greater sensitivity in African Americans (51% v 27%, P < .001 and 62% v 45%, P = .003). In contrast, Cornell voltage specificity was higher (78% v 62%, P = .09) but sensitivity was slightly lower (49% v 57%, P = 0.16) in African Americans. However, when overall test performance was compared using receiver operating curve analyses that were independent of partition value selection, ethnic differences in test performance disappeared, with no differences in accuracy of any of the ECG voltage criteria for the identification of LVH between African American and white hypertensive individuals. CONCLUSIONS: When standard, non-ethnicity-specific thresholds for the identification of LVH are used, Sokolow-Lyon and 12-lead voltage overestimate and Cornell voltage underestimates the presence and severity of LVH in African American relative to white individuals. However, these apparent ethnic differences in test performance disappear when ethnic differences in the distribution of ECG LVH criteria are taken into account. These findings demonstrate that ethnicity-specific ECG criteria can equalize detection of anatomic LVH in African American and white patients.

Aged↗
PubMedDate not supplied

The rationale and design of the Glycemic Effects in Diabetes Mellitus Carvedilol-Metoprolol Comparison in Hypertensives (GEMINI) trial.

Beta-blockers utilized in the Type 2 diabetic patient result in an even greater decrease in cardiac events than in the nondiabetic patient. Unfortunately, first-and second-generation beta-blockers are associated with the worsening of insulin resistance, deterioration of glycemic control, peripheral vasoconstriction, potentially worsening peripheral vascular disease, and more frequent and severe hypoglycemia. The third-generation beta-blockers have unique properties, including alpha1-blockade, and have been shown to lower insulin resistance, improve glycemic control, and vasodilate resistance arterioles. The Glycemic Effects in Diabetes Mellitus: Carvedilol-Metoprolol Comparison in Hypertensives (GEMINI) trial has been designed to compare a third-generation (carvedilol) with a second-generation beta-blocker (metoprolol) in a cohort of participants with hypertension and Type 2 diabetes. The primary outcome measure of the study is change in the HbA1c. The study is powered to detect a difference in HbA1c of 0.3 units (%) between the groups. Secondary endpoints include changes in insulin resistance, fasting glucose, and the lipid profile. Differences in the side-effect profile (cold extremities, fatigue, impotence, and hypoglycemia) will also be assessed. The GEMINI trial, therefore, is the first large randomized trial to assess whether utilizing a third-generation beta-blocker yields a favorable metabolic profile in the patient with Type 2 diabetes and hypertension.

Adrenergic beta-Antagonists↗
PubMedDate not supplied

Pacing therapy in the elderly.

Bradycardia due to sinus node dysfunction and atrioventricular block is more commonly observed in the elderly. Aging is associated with progressive fibrosis in both the sinus node and atrioventricular conduction system (AV node, His bundle, right and left bundles). In the absence of reversible causes implantation of a permanent pacemaker is often required in the patient with symptomatic bradycardia. For elderly patients with sinus node dysfunction, pacing modes that preserve atrioventricular synchrony are associated with a reduced incidence of atrial fibrillation and improved quality of life. For patients with atrioventricular block, the importance of preserving atrioventricular synchrony in the elderly is controversial and is currently being evaluated.

Aged↗
PubMedDate not supplied

Evaluation of asthma control by physicians and patients: comparison with current guidelines.

BACKGROUND: Current asthma consensus guidelines recommend a series of criteria for determining whether asthma is controlled. It is not known whether physicians are using these criteria to assess treatment needs and how effective such assessments are compared with patient assessment of asthma control. OBJECTIVE: To compare the parameters used by physicians and patients with asthma to determine whether asthma control is acceptable, according to the current Canadian asthma consensus guidelines. DATA AND METHODS: A total of 183 Canadian physicians, mostly general practitioners, evaluated 856 patients with mildly to moderately uncontrolled asthma who were not using anti-inflammatory medications at the time of entry in the study. Physician characteristics and patient demographics were obtained. The physicians completed two questionnaires, one assessing the level of asthma control of the patient on an ordinal scale from 1 (very poor) to 5 (very good) and another indicating the parameters that were used to evaluate this level of control. Patients answered an asthma control questionnaire identical to the one completed by the physician and completed a six-question asthma control questionnaire, with each question scored on a 0- to 6-point scale. RESULTS: Although according to current asthma guidelines all patients surveyed had uncontrolled asthma, 66.2% of patients and 43.3% of physicians rated control of asthma symptoms as adequate to very good. The average scores for patient- and physician-rated asthma control were 3.0 0.2 and 2.6 0.2, respectively. The average patient score on the Juniper asthma questionnaire was 12.2 6.3. Physicians used a mean of seven parameters to assess the patient's level of asthma control, mostly beta2-agonist need, followed by cough, wheezing, shortness of breath, limitation of physical activities and night-time awakenings. Pediatricians used cough more frequently as an evaluation parameter, and respirologists measured pulmonary function more often than other physcians. Some parameters not usually included in guideline criteria for control, such as fatigue, need to clear throat, colored sputum, headache and dizziness, were sometimes used by physicians. Only 10% and 18% of physicians used measurements of forced expiratory volume in 1 s and peak expiratory flow, respectively, in asthma control assessments. CONCLUSIONS: The present study shows that the selection of asthma control criteria among physicians varies and is not always in keeping with current asthma guidelines. Both patients and physicians often consider asthma to be controlled, when according to current guidelines, it is not, and patients consider their asthma better controlled than do physicians. Objective measures of airflow obstruction are rarely used to assess asthma control. The present study stresses the need for improved dissemination - to both patients and physicians - of current recommendations on how asthma control should be determined.

Adolescent↗
PubMedDate not supplied

Safety Committee.

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Chemistry Techniques, Analytical↗