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P O'Malley

Publications and source records attributed to P O'Malley.

At least 19 recordsLinked to original sources
PubMed2001

Role of fatty acids in the recovery of cardiac function during resuscitation from hemorrhagic shock.

This study tested the hypothesis that removal of fatty acids as a fuel source would improve cardiac efficiency at the expense of reduced cardiac contractile function in the isolated working heart after hemorrhage-retransfusion. Non-heparinized male Sprague-Dawley rats were anesthetized with ketamine-xylazine and were hemorrhaged to a mean arterial blood pressure of 40 mmHg for 1 h. Two-thirds volume of shed blood was reinfused together with 0.9% NaCl in a volume equal to 2.3 times the shed blood volume, followed by continuous infusion of 0.9% NaCl at 10 mL/kg per h for 3 h. Hearts were removed and perfused in closed, recirculating working mode for 60 min to measure hydraulic work and cardiac efficiency. Rates of glycolysis and glucose oxidation were assessed with [5-3H/U-14C] glucose (11 mM) in the absence or presence of 0.4 mM palmitate. Compared to baseline measurements, hemorrhage-retransfusion significantly reduced arterial blood glucose (228+/-7 versus 118+/-12 mg/dL) and non-esterified fatty acid concentrations (0.36+/-0.01 versus 0.30+/-0.02 mM), while elevating blood lactate (0.8+/-0.1 versus 2.5+/-0.4 mM). Perfusion of sham hearts with glucose-only did not alter cardiac work compared to shams perfused with glucose plus palmitate. However, shocked hearts perfused with glucose-only demonstrated a significant reduction in cardiac work compared to shocked hearts perfused with glucose plus palmitate and compared to sham hearts perfused with glucose only (P < 0.05, repeated measures ANOVA). Shocked hearts perfused with glucose plus palmitate showed no reduction in cardiac work compared to shams. Shocked hearts perfused with glucose-only had increased glucose oxidation rates compared to shams perfused with glucose plus palmitate. In sham hearts perfused with glucose-only, myocardial glycogen and triacylglycerol contents were significantly reduced compared to hearts freeze-clamped in situ. These endogenous fuels were not decreased in shocked hearts. These data indicate that hemorrhagic shock renders the heart unable to mobilize endogenous fuels, and suggest that withdrawal of fatty acid oxidation will impair myocardial energy metabolism during resuscitation.

Animals↗
PubMed2000

A comparison of bolus versus continuous cardiac output in an experimental model of heart failure.

OBJECTIVE: The majority of studies examining cardiac output measurement have been done in physiologically stable models with low thermal background noise. Research comparing continuous cardiac output (CCO) with bolus thermodilution cardiac output (COTD) measures in human and animal models have reported high correlations, negligible bias, but large limits of agreement. The purpose of this project was to compare CCO with COTD measures in an experimental model of heart failure where the cardiac output values were low and the range was narrow. DESIGN: A one-group experimental design with preintervention control measures and repeated CCO and COTD measures across nine time points. SETTING: Cardiovascular research laboratory. SUBJECTS: Thirty dogs. MEASURES AND MAIN RESULTS: Univariate and multivariate versions of repeated-measures analysis were used to assess the influences of temperature, weight, and stage of the experimental protocol on CCO, COTD, and the differences between them. The two measures CCO and COTD were assessed for agreement by using methods proposed by Bland and Altman. Two hundred and fifty pairs of measurements were obtained during sinus rhythm. The range for COTD measures was 0.5-4.67 L/min and for CCO measures 1.0-5.40 L/min. Of the 250 cardiac outputs estimated by the continuous method, 73.4% of the values were within +/-15% of that estimated by the repetitive, single thermodilution method. The mean bias for the entire protocol was 0.01 (SD = 0.51) with a range of 4.33 L/min. CONCLUSION: Agreement between the two measures may be the function of biological variability, responses to anesthesia, and technique. Bland and Altman evaluation demonstrated low bias and precision and similar levels of agreement when compared with previous studies in an experimental model where the cardiac output was low and the range was narrow.

Animals↗
PubMed2000

Should health-care systems pay for replacement therapy in patients with alpha(1)-antitrypsin deficiency? A critical review and cost-effectiveness analysis.

STUDY OBJECTIVES: Assess cost effectiveness for providing alpha(1)-antitrypsin (alpha(1)-AT) replacement therapy to individuals with severe COPD and alpha(1)-AT deficiency. MATERIALS AND METHODS: The electronic databases MEDLINE and EMBASE were searched, and relevant bibliographies were reviewed. Effect size, defined as the absolute risk difference between treated and untreated groups, was taken from the highest level of supporting evidence. The cost for providing alpha(1)-AT replacement therapy was analyzed from a payer perspective and was based on Medicare reimbursement rates. Effect size and costs were varied. The year of life saved was discounted up to 7%. RESULTS: The incremental cost per year of life saved for alpha(1)-AT replacement therapy (60 mg/kg/wk IV) in a 70-kg subject with severe alpha(1)-AT deficiency and an FEV(1) < 50% of predicted based on the National Institutes of Health (NIH) Registry mortality rate data is $13,971. The incremental cost depends substantially on the mortality rate reduction. When the effect size is altered from 10 to 70%, with the cost fixed at $52,000, the incremental cost per year of life saved ranges from $152,941 to $7,330. When effect size is 55% (as in the NIH Registry) but costs are increased almost 300%, from $52,000 to $150,000 per year, then the incremental cost per year of life saved increases from $13,971 to $40,301. CONCLUSION: No randomized, placebo-controlled trials are available to assess mortality rate reduction with alpha(1)-AT replacement therapy. The best currently available data are observational, from the NIH Registry. Based on these data, alpha(1)-AT replacement therapy is cost-effective in individuals who have severe alpha(1)-AT deficiency and severe COPD.

Cost-Benefit Analysis↗
PubMed1999

Combination antiretroviral therapy and incidence of AIDS-related malignancies.

We evaluated recent trends in the incidence of AIDS-related malignancies using Cox proportional hazards analysis in 622 men with well-characterized dates of HIV seroconversion in the San Francisco City Clinic cohort. By the end of 1996, 182 men had been diagnosed with Kaposi's sarcoma (KS), and 45 men had been diagnosed with lymphoma. The incidence of KS dropped from 3.5 to 0 per 100 person-years between 1993 through 1995 and 1996 (p = .07), whereas lymphoma incidence remained stable between these periods (1.4-1.8, p = .2). Combination antiretroviral therapy increased from 13% to 23% in 1993 through 1995 to 49% in 1996 and 79% in 1997. The decline in KS cannot be explained by earlier declines in HIV incidence, and concurrent increases in antiretroviral therapy suggests that control of viral replication may lead to a direct or indirect effect on KS pathogenesis. Failure to see such a trend for AIDS-related lymphoma may reflect inadequate follow-up time after widespread use of therapy or a need to treat earlier in the course of HIV infection to prevent HIV-associated lymphomagenesis.

AIDS-Related Opportunistic Infections↗
PubMed1999

Combination antiretroviral therapy and recent declines in AIDS incidence and mortality.

The reasons for recent declines in AIDS incidence and mortality may include advances in treatment, but these may be confounded by earlier declines in the incidence of human immunodeficiency virus (HIV) infection. To determine whether the declines in AIDS and mortality may, in part, stem from wider use of combination antiretroviral therapy, 622 HIV-positive men with well-characterized dates of seroconversion were followed. In this group, combination therapy came into widespread use in only 1996. In a Cox proportional hazards model, the 1996 calendar period was significantly associated with slower progression to AIDS (relative hazard [RH]=0. 19, 95% confidence interval [CI], 0.05-0.69, P=.01) and death (RH=0. 45, 95% CI, 0.21-0.95, P=.04). Declines in incidence of HIV infection, changes in HIV virulence, and end-point underreporting cannot fully explain the decline in AIDS and death in 1996. The introduction of combination antiretroviral therapy as the standard of care may already have had measurable effects.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Stress, coping and burnout in mental health nurses: findings from three research studies.

In this paper we present data from three research studies on stress, coping and burnout in mental health nurses. All three studies used a range of self report questionnaires. Measures included a demographic checklist, the General Health Questionnaire (GHQ-28), the Maslach Burnout Inventory, the DCL Stress Scale and the Cooper Coping Skills Scale. In all, 648 ward based mental health nurses were surveyed. There were no significant differences between levels of psychological distress on GHQ Total Score, but there were differences in caseness rates. In Study 3, some 38% of nurses were found to score at or above the criterion for caseness. The main stressors for ward staff were to do with staff shortages, health service changes, poor morale and not being notified of changes before they occurred. Differences in coping skills were found across studies. The study group with the highest stress scores also had the lowest coping skills scores. This was also associated with significantly higher alcohol consumption and greater self reported sickness absence. Scores on the Maslach Burnout Inventory showed higher levels of burnout amongst nurses in Study 3. These three studies have confirmed that stress is a problem for ward based mental health nurses. Two main implications arise from this work. Firstly we need models of the stress process that are empirically based, and which help us identify the moderating variables that reduce the impact of stressors on nurses. Secondly, we need to utilise this knowledge to deliver stress management interventions for staff. We end by outlining a model which may help us both understand the process of stress causation, and move towards our goal of stress reduction.

Adaptation, Psychological↗
PubMed1996

The spectrum of osteoarticular and soft tissue changes in patients with human immunodeficiency virus (HIV) infection.

In 1995, the World Health Organization reported that 18 million people worldwide have been infected with the human immunodeficiency virus (HIV), with projections that this number will increase to 30 to 40 million by the year 2000. Presently, in the U.S. over 1 million persons are infected. Approximately 40,000 people become newly infected each year in the U.S., a number equivalent to those who die from acquired immunodeficiency syndrome (AIDS) yearly. AIDS is now the leading cause of death in young men aged 25 to 44, and the third leading cause of death in women aged 25 to 44. A shift in the demographic profile of those infected has been noted, with an increasing proportion of minorities, heterosexuals, and children affected. The pathogenesis of HIV infection occurs mainly through immunosuppression, which increases the host's susceptibility to numerous infections. The increased incidence of certain neoplasms in this population point to the ability of the virus either to interfere with the host's tumor surveillance ability or to interact with other agents in tumorigenesis. Certain rheumatic diseases, likely with autoimmune etiologies, are increasingly being associated with HIV. The musculoskeletal system is but one of the sites in which the radiologist must always maintain a high index of suspicion for HIV or AIDS-related disease. The spectrum of osteoarticular and soft tissue changes observed in this population is described.

Adult↗
PubMed1995

Recommended guidelines for uniform reporting of pediatric advanced life support: the pediatric Utstein Style. A statement for healthcare professionals from a task force of the American Academy of Pediatrics, the American Heart Association, and the European Resuscitation Council. Writing Group.

This consensus document is an attempt to provide an organized method of reporting pediatric ALS data in out-of-hospital, emergency department, and in-hospital settings. For this methodology to gain wide acceptance, the task force encourages development of a common data set for both adult and pediatric ALS interventions. In addition, every effort should be made to ensure that consistent definitions are used in all age groups. As health care changes, we will all be challenged to document the effectiveness of what we currently do and show how new interventions or methods of treatment improve outcome and/or reduce cost. Only through collaborative research will we obtain the necessary data. For these reasons, and to improve the quality of care and patient outcomes, it is the hope of the task force that clinical researchers will follow the recommendations in this document. It is recognized that further refinements of this statement will be needed; these recommendations will improve only when researchers, clinicians, and EMS personnel use them, work with them, and modify them. Suggestions, emendations, and other comments aimed at improving the reporting of pediatric resuscitation should be sent to Arno Zaritsky, MD, Eastern Virginia Medical School, Children's Hospital of the King's Daughter, Division of Critical Care Medicine, 601 Children's Lane, Norfolk, VA 23507.

Child↗
PubMed1995

Health insurance and use of medical services by men infected with HIV.

Among 178 HIV-infected men from the San Francisco City Clinic Cohort (SFCCC), we examined the association between health insurance and use of outpatient services and treatment. For men with private insurance, we also assessed the frequency of avoiding the use of health insurance. Men without private insurance reported fewer outpatient visits than men with fee-for-service or managed-care plans. Use of zidovudine for eligible men was similar for those with fee-for-service plans (74%), managed-care plans (77%), or no insurance (61%). Use of Pneumocytstis carinii pneumonia prophylaxis was similar for those with fee-for-service (93%) and managed-care plans (83%) but lower for those with no insurance (63%). Of 149 men with private insurance, 31 (21%) reported that they had avoided using their health insurance for medical expenses in the previous year. In multivariate analysis, the independent predictors of avoiding the use of insurance were working for a small company and living outside the San Francisco Bay Area. Having private insurance resulted in higher use of outpatient services, but the type of private insurance did not appear to affect the use of service or treatment. Fears of loss of coverage and confidentiality may negate some benefits of health insurance for HIV-infected persons.

Adult↗
PubMed1995

Recommended guidelines for uniform reporting of pediatric advanced life support: the Pediatric Utstein Style. A statement for healthcare professionals from a task force of the American Academy of Pediatrics, the American Heart Association, and the European Resuscitation Council.

This consensus document is an attempt to provide an organized method of reporting pediatric ALS data in out-of-hospital, emergency department, and in-hospital settings. For this methodology to gain wide acceptance, the task force encourages development of a common data set for both adult and pediatric ALS interventions. In addition, every effort should be made to ensure that consistent definitions are used in all age groups. As health care changes, we will all be challenged to document the effectiveness of what we currently do and show how new interventions or methods of treatment improve outcome and/or reduce cost. Only through collaborative research will we obtain the necessary data. For these reasons, and to improve the quality of care and patient outcomes, it is the hope of the task force that clinical researchers will follow the recommendations in this document. It is recognized that further refinements of this statement will be needed; these recommendations will improve only when researchers, clinicians, and EMS personnel use them, work with them, and modify them. Suggestions, recommendations, and other comments aimed at improving the reporting of pediatric resuscitation should be sent to Arno Zaritsky, MD, Eastern Virginia Medical School, Children's Hospital of The King's Daughter, Division of Critical Care Medicine, 601 Children's Lane, Norfolk, VA 23507.

Child↗
PubMed1995

Recommended guidelines for uniform reporting of pediatric advanced life support: the pediatric Utstein style.

This statement is the product of a task force meeting held June 8, 1994, in Washington DC in conjunction with the First International Conference on Pediatric Resuscitation and a follow-up task force writing group meeting held September 18, 1994, in Chicago. Draft versions of the statement were circulated for comment to all members of the task force, the American Heart Association Subcommittee on Pediatric Resuscitation, and several outside reviewers. This statement and the International Conference on Pediatric Resuscitation were cosponsored by the American Academy of Pediatrics and the American Heart Association. The development of this statement was authorized by the American Academy of Pediatrics; the American Heart Association National Subcommittees on Pediatric Resuscitation, Basic Life Support, and Advanced Cardiac Life Support, the Committee on Emergency Cardiac Care, the Science Advisory Committee; and the European Resuscitation Council. In addition to the writing group, members of the Pediatric Utstein Task Force are Paul Anderson, M Douglas Baker, Jane Ball, Desmond Bohn, Dena Brownstein, J Michael Dean, Niranjan Kissoon, Bruce Klein, Patrick Malone, Karin McCloskey, James McCrory, P Pearl O'Rourke, Mary Patterson, Charles Schleien, James Seidel, Joseph J Tepas III, and Becky Yano.

Child↗
PubMed1995

Recommended guidelines for uniform reporting of pediatric advanced life support: the pediatric Utstein style. A statement for healthcare professionals from a task force of the American Academy of Pediatrics, the American Heart Association, and the European Resuscitation Council.

This consensus document is an attempt to provide an organized method of reporting pediatric ALS data in out-of-hospital, emergency department, and in-hospital settings. For this methodology to gain wide acceptance, the task force encourages development of a common data set for both adult and pediatric ALS interventions. In addition, every effort should be made to ensure that consistent definitions are used in all age groups. As health care changes, we will all be challenged to document the effectiveness of what we currently do and show how new interventions or methods of treatment improve outcome and/or reduce cost. Only through collaborative research will we obtain the necessary data. For these reasons, and to improve the quality of care and patient outcomes, it is the hope of the task force that clinical researchers will follow the recommendations in this document. It is recognized that further refinements of this statement will be needed; these recommendations will improve only when researchers, clinicians, and EMS personnel use them, work with them, and modify them. Suggestions, emendations, and other comments aimed at improving the reporting of pediatric resuscitation should be sent to Arno Zaritsky, MD, Eastern Virginia Medical School, Children's Hospital of The King's Daughter, Division of Critical Care Medicine, 601 Children's Lane, Norfolk, VA 23507.

Child↗