Publications by authors named "Jeremy Morton"

27 Publications

  • Page 1 of 1

The 30-Year Influence of a Regional Consortium on Quality Improvement in Cardiac Surgery.

Ann Thorac Surg 2020 07 23;110(1):63-69. Epub 2019 Nov 23.

Section of Cardiology, Department of Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire.

Background: The Northern New England Cardiovascular Disease Study Group (NNECDSG) was founded in 1987 as a regional consortium to improve cardiovascular quality in Maine, New Hampshire, and Vermont. We sought to assess the longitudinal impact of the NNECDSG on quality and cost of coronary artery bypass grafting (CABG) during the past 30 years.

Methods: Patients undergoing isolated CABG at 5 medical centers from 1987-2017 were retrospectively reviewed (n = 67,942). They were divided into 4 time periods: 1987-1999 (n = 36,885), 2000-2005 (n = 14,606), 2006-2011(n = 8470), and 2012-2017 (n = 7981). The first period was the time the NNECDSG initiated a series of quality improvement initiatives including data feedback, quality improvement training, process mapping, and site visits.

Results: Throughout the 4 time intervals, there was a consistent decline in in-hospital mortality, from 3.4% to 1.8% despite an increase in predicted risk of mortality (P < .001), and a significant decline in in-hospital morbidity, including return to the operating room for bleeding, acute kidney injury, mediastinitis, and low output failure (P < .001). Median length of stay decreased from 7 to 5 days (P < .001), which translated into potential savings of $82,722,023. There was a decrease in use of red blood cells from 3.1 units to 2.6 units per patient in the most current time, which translated into potential savings of $1,985,456.

Conclusions: By using collaborative quality improvement initiatives, the NNECDSG has succeeded in significant, sustained improvements in quality and cost for CABG during the past 30 years. These data support the utility of a regional consortium in improving quality.
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http://dx.doi.org/10.1016/j.athoracsur.2019.10.008DOI Listing
July 2020

Secondhand smoke exposure at home among one billion children in 21 countries: findings from the Global Adult Tobacco Survey (GATS).

Tob Control 2016 12 11;25(e2):e95-e100. Epub 2016 Feb 11.

Tobacco Free Initiative, World Health Organization, Geneva, Switzerland.

Objective: Children are vulnerable to secondhand smoke (SHS) exposure because of limited control over their indoor environment. Homes remain the major place where children may be exposed to SHS. Our study examines the magnitude, patterns and determinants of SHS exposure in the home among children in 21 countries (19 low-income and middle-income countries and 2 high-income countries).

Methods: Global Adult Tobacco Survey (GATS) data, a household survey of people 15 years of age or older. Data collected during 2009-2013 were analysed to estimate the proportion of children exposed to SHS in the home. GATS estimates and 2012 United Nations population projections for 2015 were also used to estimate the number of children exposed to SHS in the home.

Results: The proportion of children younger than 15 years of age exposed to SHS in the home ranged from 4.5% (Panama) to 79.0% (Indonesia). Of the approximately one billion children younger than 15 years of age living in the 21 countries under study, an estimated 507.74 million were exposed to SHS in the home. China, India, Bangladesh, Indonesia and the Philippines accounted for almost 84.6% of the children exposed to SHS. The prevalence of SHS exposure was higher in countries with higher adult smoking rates and was also higher in rural areas than in urban areas, in most countries.

Conclusions: A large number of children were exposed to SHS in the home. Encouraging of voluntary smoke-free rules in homes and cessation in adults has the potential to reduce SHS exposure among children and prevent SHS-related diseases and deaths.
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http://dx.doi.org/10.1136/tobaccocontrol-2015-052693DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5488799PMC
December 2016

Waterpipe Tobacco Smoking in Turkey: Policy Implications and Trends from the Global Adult Tobacco Survey (GATS).

Int J Environ Res Public Health 2015 Dec 8;12(12):15559-66. Epub 2015 Dec 8.

Centers for Disease Control and Prevention, Atlanta, GA 30341, USA.

Waterpipe tobacco smoking (WTS) is an emerging tobacco product globally, especially among adolescents and young adults who may perceive WTS as a safe alternative to smoking cigarettes. Monitoring the use of WTS in Turkey in relation to the tobacco control policy context is important to ensure that WTS does not become a major public health issue in Turkey. The Global Adult Tobacco Survey (GATS) was conducted in Turkey in 2008 and was repeated in 2012. GATS provided prevalence estimates on current WTS and change over time. Other indicators of WTS were also obtained, such as age of initiation and location of use. Among persons aged 15 and older in Turkey, the current prevalence of WTS decreased from 2.3% in 2008 to 0.8% in 2012, representing a 65% relative decline. Among males, WTS decreased from 4.0% to 1.1% (72% relative decline). While the overall smoking prevalence decreased among females, there was no change in the rate of WTS (0.7% in 2008 vs. 0.5% in 2012), though the WTS prevalence rate was already low in 2008. Comprehensive tobacco control efforts have been successful in reducing the overall smoking prevalence in Turkey, which includes the reduction of cigarette smoking and WTS. However, it is important to continue monitoring the use of waterpipes in Turkey and targeting tobacco control efforts to certain groups that may be vulnerable to future WTS marketing (e.g., youth, women).
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http://dx.doi.org/10.3390/ijerph121215004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4690940PMC
December 2015

Awareness and Current Use of Electronic Cigarettes in Indonesia, Malaysia, Qatar, and Greece: Findings From 2011-2013 Global Adult Tobacco Surveys.

Nicotine Tob Res 2016 Apr 20;18(4):501-7. Epub 2015 Apr 20.

Global Tobacco Control Branch, Office on Smoking and Health, National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, GA;

Introduction: Increases in electronic cigarette (e-cigarette) awareness and current use have been documented in high income countries but less is known about middle and low income countries.

Methods: Nationally representative household survey data from the first four Global Adult Tobacco Surveys to assess e-cigarettes were analyzed, including Indonesia (2011), Malaysia (2011), Qatar (2013), and Greece (2013). Correlates of e-cigarette awareness and current use were calculated. Sample sizes for Greece and Qatar allowed for further analysis of e-cigarette users.

Results: Awareness of e-cigarettes was 10.9% in Indonesia, 21.0% in Malaysia, 49.0% in Qatar, and 88.5% in Greece. In all four countries, awareness was higher among male, younger, more educated, and wealthier respondents. Current e-cigarette use among those aware of e-cigarettes was 3.9% in Malaysia, 2.5% in Indonesia, 2.2% in Greece and 1.8% in Qatar. Across these four countries, an estimated 818 500 people are currently using e-cigarettes. Among current e-cigarette users, 64.4% in Greece and 84.1% in Qatar also smoked cigarettes, and, 10.6% in Greece and 6.0% in Qatar were never-smokers.

Conclusions: E-cigarette awareness and use was evident in all four countries. Ongoing surveillance and monitoring of awareness and use of e-cigarettes in these and other countries could help inform tobacco control policies and public health interventions. Future surveillance should monitor use of e-cigarettes among current smokers and uptake among never-smokers and relapsing former smokers.
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http://dx.doi.org/10.1093/ntr/ntv081DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5100820PMC
April 2016

Methodology of the Global Adult Tobacco Survey - 2008-2010.

Glob Health Promot 2016 Jun 16;23(2 Suppl):3-23. Epub 2013 Sep 16.

World Health Organization, Geneva, Switzerland.

In 2008, the Centers for Disease Control and Prevention (CDC) and the World Health Organization developed the Global Adult Tobacco Survey (GATS), an instrument to monitor global tobacco use and measure indicators of tobacco control. GATS, a nationally representative household survey of persons aged 15 years or older, was conducted for the first time during 2008-2010 in 14 low- and middle-income countries. In each country, GATS used a standard core questionnaire, sample design, and procedures for data collection and management and, as needed, added country-specific questions that were reviewed and approved by international experts. The core questionnaire included questions about various characteristics of the respondents, their tobacco use (smoking and smokeless), and a wide range of tobacco-related topics (cessation; secondhand smoke; economics; media; and knowledge, attitudes, and perceptions). In each country, a multistage cluster sample design was used, with households selected proportionate to the size of the population. Households were chosen randomly within a primary or secondary sampling unit, and one respondent was selected at random from each household to participate in the survey. Interviewers administered the survey in the country's local language(s) using handheld electronic data collection devices. Interviews were conducted privately, and same-sex interviewers were used in countries where mixed-sex interviews would be culturally inappropriate. All 14 countries completed the survey during 2008-2010. In each country, the ministry of health was the lead coordinating agency for GATS, and the survey was implemented by national statistical organizations or surveillance institutes. This article describes the background and rationale for GATS and includes a comprehensive description of the survey methods and protocol.
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http://dx.doi.org/10.1177/1757975913499800DOI Listing
June 2016

Tracking MPOWER in 14 countries: results from the Global Adult Tobacco Survey, 2008-2010.

Glob Health Promot 2016 Jun 16;23(2 Suppl):24-37. Epub 2013 Sep 16.

Headquarters, WHO, Geneva, Switzerland.

Background: The World Health Organization (WHO) MPOWER is a technical package of six tobacco control measures that assist countries in meeting their obligations of the WHO Framework Convention Tobacco Control and are proven to reduce tobacco use. The Global Adult Tobacco Survey (GATS) systematically monitors adult tobacco use and tracks key tobacco control indicators.

Methods: GATS is a nationally representative household survey of adults aged 15 and older, using a standard and consistent protocol across countries; it includes information on the six WHO MPOWER measures. GATS Phase I was conducted from 2008-2010 in 14 high-burden low- and middle-income countries. We selected one key indicator from each of the six MPOWER measures and compared results across 14 countries.

Results: Current tobacco use prevalence rates ranged from 16.1% in Mexico to 43.3% in Bangladesh. We found that the highest rate of exposure to secondhand smoke in the workplace was in China (63.3%). We found the highest 'smoking quit attempt' rates in the past 12 months among cigarette smokers in Viet Nam (55.3%) and the lowest rate was in the Russian Federation (32.1%). In five of the 14 countries, more than one-half of current smokers in those 5 countries said they thought of quitting because of health warning labels on cigarette packages. The Philippines (74.3%) and the Russian Federation (68.0%) had the highest percentages of respondents noticing any cigarette advertising, promotion and sponsorship. Manufactured cigarette affordability ranged from 0.6% in Russia to 8.0% in India.

Conclusions: Monitoring tobacco use and tobacco control policy achievements is crucial to managing and implementing measures to reverse the epidemic. GATS provides internationally-comparable data that systematically monitors and tracks the progress of the other five MPOWER measures.
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http://dx.doi.org/10.1177/1757975913501911DOI Listing
June 2016

An integrated model for developing research skills in an undergraduate medical curriculum: appraisal of an approach using student selected components.

Perspect Med Educ 2013 Sep;2(4):230-47

Centre for Medical Education, Chancellor's Building, University of Edinburgh, Edinburgh, UK,

Student selected components (SSCs), at that time termed special study modules, were arguably the most innovative element in Tomorrow's Doctors (1993), the document from the General Medical Council that initiated the modernization of medical curricula in the UK. SSCs were proposed to make up one-third of the medical curriculum and provide students with choice, whilst allowing individual schools autonomy in how SSCs were utilized. In response, at the University of Edinburgh the undergraduate medical curriculum provides an integrated and sequential development and assessment of research skill learning outcomes, for all students in the SSC programme. The curriculum contains SSCs which provide choice to students in all 5 years. There are four substantial timetabled SSCs where students develop research skills in a topic and speciality of their choice. These SSCs are fully integrated and mapped with core learning outcomes and assessment, particularly with the 'Evidence-Based Medicine and Research' programme theme. These research skills are developed incrementally and applied fully in a research project in the fourth year. One-third of students also perform an optional intercalated one-year honours programme between years 2 and 3, usually across a wide range of honours schools at the biomedical science interface. Student feedback is insightful and demonstrates perceived attainment of research competencies. The establishment of these competencies is discussed in the context of enabling junior graduate doctors to be effective and confident at utilizing their research skills to effectively practice evidence-based medicine. This includes examining their own practice through clinical audit, developing an insight into the complexity of the evidence base and uncertainty, and also gaining a view into a career as a clinical academic.
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http://dx.doi.org/10.1007/s40037-013-0079-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3792228PMC
September 2013

Cross-country comparison of waterpipe use: nationally representative data from 13 low and middle-income countries from the Global Adult Tobacco Survey (GATS).

Tob Control 2014 Sep 11;23(5):419-27. Epub 2013 Jun 11.

Office on Smoking and Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.

Objective: Evidence shows that smoking tobacco using a waterpipe is significantly associated with diseases. Despite this, waterpipe use seems to be increasing worldwide, though nationally representative data are not widely available. The Global Adult Tobacco Survey (GATS) provides an opportunity to measure various indicators of waterpipe use from nationally representative surveys.

Methods: Data were obtained for adults 15 years of age or older from 13 countries (Bangladesh, Brazil, China, Egypt, India, Mexico, Philippines, Russia, Thailand, Turkey, Ukraine, Uruguay and Vietnam) who completed GATS from 2008-2010. The GATS questionnaire collected data on current waterpipe use, including daily/less than daily prevalence and number of sessions per day/week. An optional waterpipe module measured former use, age of initiation, and level of consumption during a session.

Results: GATS was successful in producing nationally representative data on waterpipe use from 13 countries, many of which for the first time. The prevalence of waterpipe use among men was highest in Vietnam (13.0%) and Egypt (6.2%); among women, waterpipe use was highest in Russia (3.2%) and Ukraine (1.1%). While over 90% of adults in Ukraine thought smoking tobacco causes serious illness, only 31.4% thought smoking tobacco using a waterpipe causes serious illness.

Conclusions: GATS data provide the ability to analyse waterpipe use within a country and across countries. Monitoring of waterpipe use at a national level will better enable countries to target tobacco control interventions such as education campaigns about the negative health effects of waterpipe use.
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http://dx.doi.org/10.1136/tobaccocontrol-2012-050841DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4145417PMC
September 2014

Methodology of Global Adult Tobacco Survey (GATS), Malaysia, 2011.

Int J Public Health Res 2013;3(2):297-305

World Health Organization, Avenue Appia 20, Switzerland.

Introduction: Malaysia participated in the second phase of the Global Adult Tobacco Survey (GATS) in 2011. GATS, a new component of the Global Tobacco Surveillance System, is a nationally representative household survey of adults 15 years old or above. The objectives of GATS Malaysia were to (i) systematically monitor tobacco use among adults and track key indicators of tobacco control and (ii) track the implementation of some of the Framework Convention of Tobacco Control (FCTC)-recommended demand related policies.

Methods: GATS Malaysia 2011 was a nationwide cross-sectional survey using multistage stratified sampling to select 5112 nationally representative households. One individual aged 15 years or older was randomly chosen from each selected household and interviewed using handheld device. GATS Core Questionnaire with optional questions was pre-tested and uploaded into handheld devices after repeated quality control processes. Data collectors were trained through a centralized training. Manuals and picture book were prepared to aid in the training of data collectors and during data collection. Field-level data were aggregated on a daily basis and analysed twice a week. Quality controls were instituted to ensure collection of high quality data. Sample weighting and analysis were conducted with the assistance of researchers from the Centers for Disease Control and Prevention, Atlanta, USA.

Results: GATS Malaysia received a total response rate of 85.3% from 5112 adults surveyed. Majority of the respondents were 25-44 years old and Malays.

Conclusions: The robust methodology used in the GATS Malaysia provides national estimates for tobacco used classified by socio-demographic characteristics and reliable data on various dimensions of tobacco control.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4593763PMC
January 2013

Tobacco use in 3 billion individuals from 16 countries: an analysis of nationally representative cross-sectional household surveys.

Lancet 2012 Aug;380(9842):668-79

Department of Community Health and Health Behavior, School of Public Health and Health Professions, University at Buffalo, The State University of New York, Buffalo, NY 14214-8028, USA. ggiovino@buff alo.edu

Background: Despite the high global burden of diseases caused by tobacco, valid and comparable prevalence data for patterns of adult tobacco use and factors influencing use are absent for many low-income and middle-income countries. We assess these patterns through analysis of data from the Global Adult Tobacco Survey (GATS).

Methods: Between Oct 1, 2008, and March 15, 2010, GATS used nationally representative household surveys with comparable methods to obtain relevant information from individuals aged 15 years or older in 14 low-income and middle-income countries (Bangladesh, Brazil, China, Egypt, India, Mexico, Philippines, Poland, Russia, Thailand, Turkey, Ukraine, Uruguay, and Vietnam). We compared weighted point estimates and 95% CIs of tobacco use between these 14 countries and with data from the 2008 UK General Lifestyle Survey and the 2006-07 US Tobacco Use Supplement to the Current Population Survey. All these surveys had cross-sectional study designs.

Findings: In countries participating in GATS, 48·6% (95% CI 47·6-49·6) of men and 11·3% (10·7-12·0) of women were tobacco users. 40·7% of men (ranging from 21·6% in Brazil to 60·2% in Russia) and 5·0% of women (0·5% in Egypt to 24·4% in Poland) in GATS countries smoked a tobacco product. Manufactured cigarettes were favoured by most smokers (82%) overall, but smokeless tobacco and bidis were commonly used in India and Bangladesh. For individuals who had ever smoked daily, women aged 55-64 years at the time of the survey began smoking at an older age than did equivalently aged men in most GATS countries. However, those individuals who had ever smoked daily and were aged 25-34-years when surveyed started to do so at much the same age in both sexes. Quit ratios were very low (<20% overall) in China, India, Russia, Egypt, and Bangladesh.

Interpretation: The first wave of GATS showed high rates of smoking in men, early initiation of smoking in women, and low quit ratios, reinforcing the view that efforts to prevent initiation and promote cessation of tobacco use are needed to reduce associated morbidity and mortality.

Funding: Bloomberg Philanthropies' Initiative to Reduce Tobacco Use, Bill and Melinda Gates Foundation, Brazilian and Indian Governments.
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http://dx.doi.org/10.1016/S0140-6736(12)61085-XDOI Listing
August 2012

Electronic data collection and management system for global adult tobacco survey.

Online J Public Health Inform 2012 14;4(2). Epub 2012 Sep 14.

Tobacco Free Initiative, World Health Organization, Geneva Switzerland.

Introduction: Portable handheld computers and electronic data management systems have been used for national surveys in many high-income countries, however their use in developing countries has been challenging due to varying geographical, economic, climatic, political and cultural environments. In order to monitor and measure global adult tobacco use, the World Health Organization and the US Centers for Disease Control and Prevention initiated the Global Adult Tobacco Survey, a nationally representative household survey of adults, 15 years of age or older, using a standard core questionnaire, sample design, and data collection and management procedures. The Survey has been conducted in 14 low- and middle-income countries, using an electronic data collection and management system. This paper describes implementation of the electronic data collection system and associated findings.

Methods: The Survey was based on a comprehensive data management protocol, to enable standardized, globally comparable high quality data collection and management. It included adaptation to specific country needs, selection of appropriate handheld hardware devices, use of open source software, and building country capacity and provide technical support.

Results: In its first phase, the Global Adult Tobacco Survey was successfully conducted between 2008 and 2010, using an electronic data collection and management system for interviews in 302,800 households in 14 countries. More than 2,644 handheld computers were fielded and over 2,634 fieldworkers, supervisors and monitors were trained to use them. Questionnaires were developed and programmed in 38 languages and scripts. The global hardware failure rate was < 1% and data loss was almost 0%.

Conclusion: Electronic data collection and management systems can be used effectively for conducting nationally representative surveys, particularly in low- and middle-income countries, irrespective of geographical, climatic, political and cultural environments, and capacity-building at the country level is an important vehicle for Health System Strengthening.
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http://dx.doi.org/10.5210/ojphi.v4i2.4190DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3615815PMC
April 2013

The association of perioperative red blood cell transfusions and decreased long-term survival after cardiac surgery.

Anesth Analg 2009 Jun;108(6):1741-6

Dartmouth-Hitchcock Medical Center, Department of surgery, 1 Medical Center Drive Lebanon, NH 03756, USA. Stephen.D.Surgenor@Hitchcock

Background: Exposure to red blood cell (RBC) transfusions has been associated with increased mortality after cardiac surgery. We examined long-term survival for cardiac surgical patients who received one or two RBC units during index hospitalization.

Methods: Nine thousand seventy-nine consecutive patients undergoing coronary artery bypass graft, valve, or coronary artery bypass graft/valve surgery at eight centers in northern New England during 2001-2004 were examined after exclusions. A probabilistic match between the regional registry and the Social Security Administration's Death Master File determined mortality through June 30, 2006. Cox Proportional Hazard and propensity methods were used to calculate adjusted hazard ratios.

Results: Thirty-six percent of patients (n = 3254) were exposed to one or two RBC units. Forty-three percent of RBCs were given intraoperatively, 56% in the postoperative period and 1% were preoperative. Patients transfused were more likely to be anemic, older, smaller, female and with more comorbid illness. Survival was significantly decreased for all patients exposed to 1 or 2 U of RBCs during hospitalization for cardiac surgery compared with those who received none (P < 0.001). After adjustment for patient and disease characteristics, patients exposed to 1 or 2 U of RBCs had a 16% higher long-term mortality risk (adjusted hazard ratios = 1.16, 95% CI: 1.01-1.34, P = 0.035).

Conclusions: Exposure to 1 or 2 U of RBCs was associated with a 16% increased hazard of decreased survival after cardiac surgery.
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http://dx.doi.org/10.1213/ane.0b013e3181a2a696DOI Listing
June 2009

Characterization of a prospective human model for study of the reproductive hormone responses to major illness.

Am J Physiol Endocrinol Metab 2008 Jul 15;295(1):E63-9. Epub 2008 Apr 15.

Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Maine Medical Center, 22 Bramhall St., Portland, ME 04102, USA.

With critical illness, serum testosterone levels fall markedly, whereas estrogen levels rise. Although animal studies suggest adaptive advantages, no prospective model has been available for studies in humans. We hypothesized that coronary artery bypass graft (CABG) surgery would provide such a model by eliciting the same reproductive hormone and other endocrine responses as reported with major nonsurgical illnesses. We further hypothesized that those responses would occur consistently in all CABG patients with predictable time courses, providing reliable windows for prospective studies. In 17 men undergoing CABG, serum levels of reproductive hormones, cortisol, thyroid hormones, and IGF-I were measured before and for up to 5 wk after surgery. Changes in serum levels of reproductive and other hormones were similar to those reported in nonsurgical critically ill patients. Time course for onset, duration, and recovery of reproductive hormone changes were consistent among all patients. A window for studying the testosterone and estrogen responses was established as the first 5 days following CABG. Practical use of this model was demonstrated by evaluating, in another seven men, changes in gonadotroph responsiveness to GnRH following CABG. Finally, to determine whether our findings in CABG could be extended to other surgeries, we demonstrated similar endocrine responses in 12 men following abdominal aortic aneurysm resection. We conclude that patients undergoing CABG surgery provide a useful human model for the prospective evaluation of the reproductive axis responses to acute illness. Other major surgeries are likely to also be suitable for these studies.
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http://dx.doi.org/10.1152/ajpendo.00472.2007DOI Listing
July 2008

Back to the future: teaching medical students clinical procedures.

Med Teach 2006 Dec;28(8):723-8

Medical Teaching Organisation, University of Edinburgh, Scotland, UK.

Over the last decade undergraduate training in clinical procedures has moved from 'learning on patients' towards simulation-based training. Simulation was intended to be an adjunct rather than a replacement for experiential learning and several initiatives have emerged to redress this balance. With these initiatives in mind, we evaluated the impact of our undergraduate skills training programme and considered the need to change our teaching and learning strategy in this area. Outcomes-based data was accrued from the performance-based assessment of 64 medical students in four key procedures. Attitudinal data was gleaned from 130 responses to an electronic questionnaire and student self-efficacy ratings taken immediately before assessment. Students performed best in venepuncture. Performance in the other skills revealed 1 in 3 did not reach competence in i.v. cannulation and more than 1 in 2 were below standard when measuring a BM stix and priming an i.v. giving set. The data on self-efficacy and competence was analysed and a Spearman's Rank Correlation coefficient of 0.36 calculated. Students in final year were poor self-assessors and unaware that their skills often fell below standard. These results suggest a need to increase students' self-awareness and promote ward-based learning. This article considers how these objectives might be achieved.
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http://dx.doi.org/10.1080/01421590601110025DOI Listing
December 2006

Increases in serum estrogen levels during major illness are caused by increased peripheral aromatization.

Am J Physiol Endocrinol Metab 2006 Sep 2;291(3):E631-8. Epub 2006 May 2.

Division of Reproductive Endocrinology, Dept. of Ob/Gyn, Maine Medical Center, Portland, ME 04102, USA.

Although serum testosterone levels decrease acutely in critically ill patients, estrogen levels rise. We hypothesized that increased rates of aromatization of androgens to estrogens underlie the increase in serum estrogen levels. Eleven men and three women (age 42-69 yr) were prospectively studied before and again after elective coronary artery bypass graft surgery (CABG). Each patient received priming doses of [(14)C]androgen and [(3)H]estrogen that were immediately followed by peripheral infusions for 210 min. Eight men and three women received androstenedione (A(4))/estrone (E(1)) and three men received testosterone (T)/estradiol (E(2)). Adipose tissue biopsies were obtained in another six men before and after CABG to evaluate levels of P450 aromatase mRNA. Serum T levels decreased postoperatively in all 17 men (P < 0.001), whereas E(1) levels rose (P = 0.004), with a trend toward a rise in E(2) (P = 0.23). Peripheral aromatization rates of androgens to estrogens rose markedly in all 14 patients (P < 0.0001). Estrogen clearance rates rose (P < 0.002). Mean serum A(4) levels increased slightly postoperatively (P = 0.04), although no increase in A(4) production rates (PRs) was observed. T PRs decreased in two of three men, whereas clearance rates increased in all three. Adipose tissue P450 aromatase mRNA content increased postoperatively (P < 0.001). We conclude that the primary cause of increased estrogen levels in acute illness is increased aromatase P450 gene expression, resulting in enhanced aromatization of androgens to estrogens, a previously undescribed endocrine response to acute illness. Both increased T clearance and decreased T production contribute to decreased serum T levels. Animal studies suggest that these opposing changes in circulating estrogen and androgen levels may be important to reduce morbidity and mortality in critical illness.
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http://dx.doi.org/10.1152/ajpendo.00467.2005DOI Listing
September 2006

The preoperative intraaortic balloon pump in coronary bypass surgery: a lack of evidence of effectiveness.

Am Heart J 2005 Dec;150(6):1122-7

Department of Surgery, Maritime Heart Center, Halifax, Nova Scotia, Canada.

Background: There is limited evidence demonstrating the effectiveness of preoperative intraaortic balloon pump (IABP) use in isolated coronary artery bypass graft (CABG) surgery. A single-center randomized trial demonstrated its benefit. We undertook a multicenter observational study to verify this finding.

Methods: In 29,950 consecutive patients undergoing isolated CABG between 1995 and 2000 at 10 centers, we compared patients with and without a preoperative IABP. We also compared the effect of preoperative IABP use within 7 high-risk clinical subgroups. To validate the previous randomized trial, patients with any 2 of the following were also analyzed: left main > 70%, ejection fraction < 40%, redo CABG, or preoperative intravenous nitroglycerin.

Results: Preoperative IABPs were used in 1896 patients (6.3%). These patients had more comorbid conditions and a higher crude mortality than those who did not have preoperative IABPs (9.5% vs 2.3%, P < .0001). Preoperative IABP patients were caliper matched to non-preoperative IABP patients using a propensity score. Excess mortality associated with preoperative IABP persisted (9.2% vs 5.8%, P = .0004). In 7 high-risk subgroups, mortality was significantly higher with preoperative IABP. We used propensity caliper matching to compare preoperative IABP with non-preoperative IABP patients who met trial criteria (n = 4332). Preoperative IABP was associated with higher mortality (11.0% vs 6.5%, P = .0009). Removing emergency patients did not alter results.

Conclusions: Use of preoperative IABPs was consistently associated with higher mortality. Despite detailed statistical analysis, we were unable to show benefit from preoperative IABP use or confirm the results of a single-center trial that demonstrated its benefit. Assessment of preoperative IABP efficacy will require a randomized trial.
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http://dx.doi.org/10.1016/j.ahj.2005.01.043DOI Listing
December 2005

Embolic activity subsequent to injection of the internal mammary artery with papaverine hydrochloride.

Heart Surg Forum 2005 ;8(6):E434-6

Department of Surgery and Community & Family Medicine and Medicine, Dartmouth Medical School, Hanover, NH 03756, USA.

Background: Neurologic injury is a rare yet devastating outcome of coronary artery bypass grafting surgery. Mechanisms producing both focal and global neurologic injuries include embolization, cerebral hypoperfusion, and hypotension. In this present study, we report an association between variations in the treatment of the internal mammary artery with the detection of cerebral embolic signals.

Methods: An intensive intraoperative neurologic and physiologic monitoring approach was implemented to associate discrete processes of clinical care with the concurrent detection of cerebral embolic signals, cerebral hypoperfusion, and hypotension. The method of treating the left internal mammary artery was tracked among 68 patients undergoing isolated coronary artery bypass grafting. Cerebral embolic signals were counted within 3 minutes of the treatment of the left internal mammary artery.

Results: Among a series of 68 patients undergoing isolated coronary artery bypass grafting, 22 were not treated with papaverine. Of those treated, 12 received injection intraluminally and 28 had a topical application. Embolic signals were noted concurrently among 7 patients receiving injection of papaverine. No embolic signals were noted among patients who were treated topically.

Conclusions: We report an association between the injection of papaverine hydrochloride and cerebral embolic signals. Our findings suggest that adoption of topical applications of papaverine hydrochloride may offer opportunities to reduce a portion of cerebral embolic signals in the setting of coronary artery bypass grafting.
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http://dx.doi.org/10.1532/HSF98.20051012DOI Listing
December 2006

A method for identifying mechanisms of neurologic injury from cardiac surgery.

Heart Surg Forum 2004 ;7(6):348-52

Department of Surgery, Dartmouth College, Hanover, New Hampshire, USA.

Background: A method for linking discrete surgical and perfusion-related processes of care with cerebral emboli, cerebral oxyhemoglobin desaturation, and hemodynamic changes may offer opportunities for reducing overall neurologic injury for patients undergoing cardiac surgery.

Methods: An intensive intraoperative neurologic and physiologic monitoring approach was developed and implemented. Mechanisms likely to produce embolic (cerebral emboli), hypoperfusion (oxyhemoglobin desaturation), and hypotensive (hemodynamic changes) neurologic injuries were monitored and synchronized with the occurrence of surgical and perfusion clinical events/techniques using a case video.

Results: The system was tested among 32 cardiac surgery patients. Emboli were measured in the cerebral arteries and outflow of the cardiopulmonary bypass circuit among nearly 75% and 85% of patients, respectively. Oxyhemoglobin desaturation was measured among nearly 70% of patients. Hemodynamic information was recorded in 100% of patients.

Conclusions: We developed and successfully implemented a method for detailed real-time associations between processes of clinical care and precursors of neurologic injury. Knowledge of this linkage will result in the redesign of clinical care to reduce a patient's risk of neurologic injury.
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http://dx.doi.org/10.1532/HSF98.20041088DOI Listing
December 2006

10-year follow-up of patients with and without mediastinitis.

Semin Thorac Cardiovasc Surg 2004 ;16(1):70-6

Maine Medical Center, Portland, ME, USA.

Mediastinitis is a dreaded complication of CABG surgery. Short-term outcomes have been described, but there have been only a few long-term studies. We examined the survival of patients undergoing isolated CABG surgery between 1992 and 2001. Mediastinitis was identified during the index admission. Proportional hazards regression was used to calculate adjusted hazard ratios (HR) and 95% confidence intervals (CI 95%). Among 36,078 consecutive patients, there were 5749 deaths during 148,319 person years of follow-up. There were 418 cases of mediastinitis (1.16%). The incidence of death was 11.15 per 100 person/years with mediastinitis and 3.81 deaths/100 person years without. (P < 0.001). We also examined the mortality rates of patients who survived at least 6 months after their CABG surgery. Patients with mediastinitis had an incidence rate of 5.70 deaths per 100 person/years while those without had a rate of 2.66 deaths per 100 person/years (P < 0.001). After adjustment for baseline differences in patient and disease characteristics, the hazard ratio was 2.12 (CI95% = 1.86,2.58; P < 0.001). The adjusted hazard ratios for patients who survived 6 months postsurgery was 1.70 (CI95% = 1.36,2.13; P < 0.001). Mediastinitis is associated with a marked increase in both acute and long-term mortality rates.
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http://dx.doi.org/10.1053/j.semtcvs.2004.01.006DOI Listing
November 2004

Survival in patients with peripheral vascular disease after percutaneous coronary intervention and coronary artery bypass graft surgery.

Ann Thorac Surg 2004 Aug;78(2):466-70; discussion 470

Section of Cardiology, Veterans Affairs Hospital, Hartland Road, White River Junction, Vermont 05006, USA.

Background: Patients with peripheral vascular disease (PVD) undergoing coronary revascularization have high rates of adverse outcomes. Whether there are important differences in outcomes for surgical versus percutaneous coronary revascularization is unknown. The objective of this study was to compare survival in patients with PVD who underwent percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) surgery for multivessel coronary artery disease.

Methods: In-hospital data were collected on 1,305 consecutive patients undergoing coronary revascularization (PCI, n = 341; CABG, n = 964) in northern New England from 1994 to 1996. Patient records were linked to the National Death Index to assess survival out to 3 years (mean 1.2 years). Logistic and Cox proportional hazards regression were used to calculate risk-adjusted odds ratios and hazard ratios.

Results: Compared with CABG patients, those undergoing PCI were more often women, had more renal failure, more prior coronary revascularizations, were more likely to have two-vessel coronary artery disease and were more likely to undergo the procedure emergently. They were less likely to have a history of heart failure. After adjusting for differences in baseline characteristics, patients undergoing CABG had better intermediate survival than did PCI patients (hazard ratio 0.68; 95% confidence interval, 0.46 to 1.00; p = 0.05).

Conclusions: Patients with multivessel coronary artery disease and PVD undergoing CABG surgery have better intermediate survival out to 3 years than similar patients undergoing PCI. This information may be useful in counseling patients with PVD requiring coronary revascularization.
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http://dx.doi.org/10.1016/j.athoracsur.2004.01.044DOI Listing
August 2004

A multicenter comparison of intraaortic balloon pump utilization in isolated coronary artery bypass graft surgery.

Ann Thorac Surg 2003 Dec;76(6):1988-92; discussion 1992

The Maritime Heart Center, Halifax, Nova Scotia, Canada.

Background: Single-center studies suggest substantial variation in intraaortic balloon pump (IABP) utilization. Our purpose is to examine IABP utilization over time and across medical centers.

Methods: This was a prospective cohort of 29,961 consecutive patients undergoing isolated coronary artery bypass graft surgery, between 1995 and 2000, at 10 centers (eight in northern New England and two in Canada).

Results: A total of 2,678 (8.9%) patients received an IABP. The rate of preoperative IABP insertion was 6.3%, and that of intra- or postoperative insertion was 2.6%. During the 6 years, IABP use increased from 7.0% to 10.3% (p(trend) <0.001). Preoperative IABP insertion increased from 5.4% to 7.8% (p(trend) < 0.001). There was no significant increase in intra-/postoperative IABP insertion 1.7% to 3.4% (p(trend) = 0.34). Adjustment for changes in patient and disease characteristics did not substantially alter these results. The rate of IABP use varied substantially by center, from 5.9% to 16.4% (p < 0.001). Adjustment for patient and disease characteristics resulted in variation from 4.8% to 12.8% across the 10 centers (p < 0.001). The adjusted rates of preoperative IABP insertion varied from 3.6% to 13.7% (p < 0.001), and the rates of intra-/postoperative IABP insertion ranged from 1.0% to 5.2% (p < 0.001). There was no significant correlation between the rates of preoperative and intra-/postoperative IABP use (r(s) = 0.085, p = 0.815).

Conclusions: During the 6 years, there was a 47% increase in the rate of IABP utilization. Even after adjustment, there was almost threefold variation in IABP use across centers. This variation likely reflects lack of consensus on the appropriate use of the IABP in CABG patients.
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http://dx.doi.org/10.1016/s0003-4975(03)01197-4DOI Listing
December 2003

Determination of etiologic mechanisms of strokes secondary to coronary artery bypass graft surgery.

Stroke 2003 Dec 6;34(12):2830-4. Epub 2003 Nov 6.

Department of Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA.

Background And Purpose: Current research focused on stroke in the setting of coronary artery bypass graft (CABG) surgery has missed important opportunities for additional understanding by failing to consider the range of different stroke mechanisms. We developed and implemented a classification system to identify the distribution and timing of stroke subtypes.

Methods: We conducted a regional study of 388 patients with the diagnosis of stroke after isolated CABG surgery in northern New England from 1992 to 2000. Data were collected on patient and disease characteristics, intraoperative and postoperative care, and outcomes. Stroke etiology was classified into 1 of the following: hemorrhage, thromboembolic (embolic, thrombotic, lacunar), hypoperfusion, other (subtype not listed above), multiple (>or=2 competing mechanisms), or unclassified (unknown mechanism). The reliability of the classification system was determined by percent agreement and kappa statistics.

Results: Embolic strokes accounted for 62.1% of strokes, followed by multiple etiologies (10.1%), hypoperfusion (8.8%), lacunar (3.1%), thrombotic (1.0%), and hemorrhage (1.0%). There were 54 strokes with unknown etiology (13.9%). There were no strokes classified as "other." Nearly 45% (105/235) of the embolic and 56% (18/32) of hypoperfusion strokes occurred within the first postoperative day.

Conclusions: We used a locally developed classification system to determine the etiologic mechanism of 388 strokes secondary to CABG surgery. The principal etiologic mechanism was embolic, followed by stroke having multiple mechanisms and hypoperfusion. Regardless of mechanism, strokes predominantly occurred within the first postoperative day.
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http://dx.doi.org/10.1161/01.STR.0000098650.12386.B3DOI Listing
December 2003

Development and validation of a prediction model for strokes after coronary artery bypass grafting.

Ann Thorac Surg 2003 Aug;76(2):436-43

Department of Surgery, Catholic Medical Center, Manchester, New Hampshire 03102, USA.

Background: A prospective study of patients undergoing coronary artery bypass graft surgery (CABG) was conducted to identify patient and disease factors related to the development of a perioperative stroke. A preoperative risk prediction model was developed and validated based on regionally collected data.

Methods: We performed a regional observational study of 33,062 consecutive patients undergoing isolated CABG surgery in northern New England between 1992 and 2001. The regional stroke rate was 1.61% (532 strokes). We developed a preoperative stroke risk prediction model using logistic regression analysis, and validated the model using bootstrap resampling techniques. We assessed the model's fit, discrimination, and stability.

Results: The final regression model included the following variables: age, gender, presence of diabetes, presence of vascular disease, renal failure or creatinine greater than or equal to 2 mg/dL, ejection fraction less than 40%, and urgent or emergency. The model significantly predicted (chi(2) [14 d.f.] = 258.72, p < 0.0001) the occurrence of stroke. The correlation between the observed and expected strokes was 0.99. The risk prediction model discriminated well, with an area under the relative operating characteristic curve of 0.70 (95% CI, 0.67 to 0.72). In addition, the model had acceptable internal validity and stability as seen by bootstrap techniques.

Conclusions: We developed a robust risk prediction model for stroke using seven readily obtainable preoperative variables. The risk prediction model performs well, and enables a clinician to estimate rapidly and accurately a CABG patient's preoperative risk of stroke.
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http://dx.doi.org/10.1016/s0003-4975(03)00528-9DOI Listing
August 2003

A 10-year review of pediatric perfusion practice in North America.

Perfusion 2002 Mar;17(2):83-9

Cardiac Surgery Department, Maine Medical Center, Portland 04102, USA.

In December 1999, 145 North American pediatric open-heart institutions were mailed an updated survey as a follow-up of two earlier surveys, 1989 and 1994. The survey consisted of 81 questions pertaining to demographics, equipment, techniques and patient monitoring. This survey, following a similar format of the two earlier surveys, provides a 10-year review encompassing both new and founded practices performed during the conduct of pediatric cardiopulmonary bypass. Responses were received from 83 hospitals, for a 57% response rate. Of the respondents, 72 were active pediatric open-heart centers, 67% performing both adult and pediatric cardiac surgery and 33% performing pediatric surgery exclusively. The mean number of pediatric cases performed in 1999 was 169, compared to 101 cases in 1989 and 145 cases in 1993. Of the 72 respondents, 51% were performing greater than 100 cases/year, whereas 3% of centers were performing under 25 cases/year. As the decade progressed, bubble oxygenators were completely replaced by their membrane counterpart. The use of ultrafiltration, reported first in the 1989 survey, has risen by over 30%. The use of colloids in the prime, specifically 25% albumin, has increased in use from 34% in 1989 to 85% in 1999. Rewarming gradients are used by 100% of respondents with a mean gradient of 9.4 degrees C between the patient and water bath. Myocardial protection has seen an increase of close to 20% in the use of blood cardioplegia. The use of safety devices is also on the rise with more centers using level detectors (79%), bubble detectors (88%) and arterial line filters (96%). Centers relying on the use of cardiac assist devices have increased by 25% since 1989. Results of this survey suggest a movement toward a higher volume of cases being performed at fewer centers. While some diversity is seen, movement toward greater homogeneity, first noted in the 1994 survey, continues in 1999.
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http://dx.doi.org/10.1191/0267659102pf542oaDOI Listing
March 2002

Operative technique, paraplegia, and mortality after blunt traumatic aortic injury.

Arch Surg 2002 Apr;137(4):434-8

Department of Surgery, Maine Medical Center, Portland, USA.

Hypothesis: The use of mechanical circulatory support (MCS) during repair of traumatic aortic injuries is associated with a decreased incidence of postoperative paraplegia and mortality.

Design And Setting: Historical cohort study with contemporaneous but nonrandomized controls in a tertiary care hospital from July 1, 1988, through December 31, 1999.

Patients And Interventions: Consecutive cases undergoing operation for traumatic aortic injuries. Use of MCS (with or without systemic heparinization) determined by surgeon preference.

Main Outcome Measures: Incidence of postoperative paraplegia and mortality.

Results: Twenty-two patients underwent repair of traumatic aortic injuries using MCS, resulting in no paraplegia but 4 deaths, 3 of them from cerebral ischemia. Thirteen patients had their traumatic aortic injuries repaired using a "clamp-and-sew" or passive shunt technique with no deaths but paraplegia in 2. Compared with an earlier report from our group from January 1, 1975, through June 30, 1988, the annual incidence of traumatic aortic injuries has decreased, whereas the age of patients and proportion of operations using MCS have increased. A review of the recent literature on traumatic aortic injuries reveals an average postoperative paraplegia incidence of 1% with MCS and 16% without MCS. Overall mortality is similar, but others have also reported cases of cerebral ischemia after aortic repair.

Conclusions: The use of MCS during repair of traumatic aortic injuries is associated with a decreased incidence of postoperative paraplegia. The occasional occurrence of cerebral ischemia deserves further study.
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http://dx.doi.org/10.1001/archsurg.137.4.434DOI Listing
April 2002

The effect of comorbid illness on mortality outcomes in cardiac surgery.

Arch Surg 2002 Apr;137(4):428-32; discussion 432-3

Department of Surgery, Eastern Maine Medical Center, Bangor, 04401, USA.

Hypothesis: Comorbid conditions are associated with the risk of death from coronary artery bypass graft surgery.

Design: Prospective cohort study data were collected on patient and disease characteristics and comorbid conditions including hypertension, diabetes, obesity, vascular disease, chronic obstructive pulmonary disease, cancer (excluding nonmelanoma skin cancer), dialysis-dependent renal failure, liver disease, and dementia. Statistical analysis used logistic regression for the calculation of adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

Setting: Regional cardiac surgery database.

Patients: A total of 27,239 consecutive patients undergoing isolated coronary artery bypass graft surgery.

Main Outcome Measure: In-hospital mortality rate.

Results: The prevalence of comorbid conditions was as follows: hypertension, 64.3%; diabetes, 30.1%; obesity, 24.6%; severe obesity, 7.2%; vascular disease, 18.3%; chronic obstructive pulmonary disease, 10.9%; peptic ulcer, 7.5%; cancer, 3.8%; renal failure, 1.5%; liver disease, 0.6%; and dementia, 0.1%. After adjustment for patient and disease characteristics, including age, sex, previous cardiac surgery, priority of surgery, degree of left main coronary stenosis, number of diseased coronary arteries, and left ventricular ejection fraction, the following comorbid conditions were significant predictors of in-hospital mortality: diabetes (OR, 1.19; 95% CI, 1.01-1.40; P =.03), vascular disease (OR, 1.67; 95% CI, 1.41-1.97; P<.001), chronic obstructive pulmonary disease (OR, 1.57; 95% CI, 1.29-1.91; P<.001), peptic ulcer (OR, 1.34; 95% CI, 1.05-1.71; P =.02), and dialysis-dependent renal failure (OR, 3.68; 95% CI, 2.65-5.13; P<.001). There was no significant association between in-hospital mortality and hypertension, obesity or severe obesity, cancer, liver disease, or dementia.

Conclusion: Even after adjustment for other patient and disease characteristics, comorbid conditions (especially diabetes, vascular disease, chronic obstructive pulmonary disease, peptic ulcer disease, and dialysis-dependent renal failure) are associated with significantly increased risk of death after coronary artery bypass graft surgery.
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http://dx.doi.org/10.1001/archsurg.137.4.428DOI Listing
April 2002

Association of bacterial infection and red blood cell transfusion after coronary artery bypass surgery.

Ann Thorac Surg 2002 Jan;73(1):138-42

Department of Medicine, Maine Medical Center, Portland 04102, USA.

Background: Previous studies have shown an association between red blood cell transfusions (RBC) and bacterial infections following coronary artery bypass graft (CABG) surgery. We sought to assess whether there is an independent effect of RBC on the incidence of bacterial infections.

Methods: This was a prospective cohort study of 533 CABG patients over a 7-month period. Subjects were followed from time of CABG until 30 days postoperatively. Data were collected on patient and treatment characteristics, surgical management, and transfusion incidence.

Results: Seventy-five (14.1%) of 533 patients developed a bacterial infection. After controlling for patient and disease characteristics, invasive treatments, surgical time, and the transfusion of other substances, the adjusted rates of bacterial infection were 4.8% for no RBC transfusion, 15.2% with one to two units, 22.1% with three to five units, and 29.0% with greater than or equal to six units, (p(trend) < 0.001). Diabetes was the only patient or disease factor significantly associated with bacterial infection (p < 0.001).

Conclusions: RBC transfusions were independently associated with a higher incidence of post-CABG bacterial infections. The risk of infection increased in proportion to the number of units of RBC transfused.
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http://dx.doi.org/10.1016/s0003-4975(01)03308-2DOI Listing
January 2002