Showing papers by "Deborah J. Cook published in 1995"
TL;DR: This multiple organ dysfunction score, constructed using simple physiologic measures of dysfunction in six organ systems, mirrors organ dysfunction as the intensivist sees it and correlates strongly with the ultimate risk of ICU mortality and hospital mortality.
Abstract: ObjectiveTo develop an objective scale to measure the severity of the multiple organ dysfunction syndrome as an outcome in critical illness.DesignSystematic literature review; prospective cohort study.SettingSurgical intensive care unit (ICU) of a tertiary-level teaching hospital.PatientsAll patient
2,443 citations
TL;DR: An approach to classifying strength of recommendations is suggested and is directed primarily at clinicians who make treatment recommendations that they hope their colleagues will follow.
Abstract: THE ULTIMATE PURPOSE of applied health research is to improve health care. Summarizing the literature to adduce recommendations for clinical practice is an important part of the process. Recently, the health sciences community has reduced the bias and imprecision of traditional literature summaries and their associated recommendations through the development of rigorous criteria for both literature overviews 1-3 and practice guidelines. 4,5 Even when recommendations come from such rigorous approaches, however, it is important to differentiate between those based on weak vs strong evidence. Recommendations based on inadequate evidence often require reversal when sufficient data become available, 6 while timely implementation of recommendations based on strong evidence can save lives. 6 In this article, we suggest an approach to classifying strength of recommendations. We direct our discussion primarily at clinicians who make treatment recommendations that they hope their colleagues will follow. However, we believe that any clinician who attends to
829 citations
TL;DR: Current evidence provides no support for the use of corticosteroids in patients with sepsis or septic shock, and suggests that their use may be harmful, underscore the need for future methodologically rigorous trials evaluating new immune-modulating therapies in well-defined critically ill patients with overwhelming infection.
Abstract: ObjectiveTo determine the effect of corticosteroid therapy on morbidity and mortality in patients with sepsis.Data SourcesWe searched for published and unpublished research using MEDLINE, EMBASE, and the Science Citation Index, manual searching of Index Medicus, citation review of relevant primary a
610 citations
603 citations
Journal Article•
TL;DR: To critically appraise and synthesize the current evidence on endoscopic ligation for esophageal variceal bleeding, a meta-analysis of the results of randomized clinical trials that compared endoscope ligation with sclerotherapy is done.
Abstract: Purpose: To compare the effect of endoscopic ligation with that of sclerotherapy in the treatment of patients with bleeding esophageal varices. Data Sources: Strategies to identify published and un...
596 citations
TL;DR: In this paper, the effect of endoscopic ligation compared with sclerotherapy in the treatment of patients with bleeding esophageal varices was compared in seven randomized trials.
Abstract: Purpose To compare the effect of endoscopic ligation with that of sclerotherapy in the treatment of patients with bleeding esophageal varices. Data sources Strategies to identify published and unpublished research included searches of computerized bibliographic and scientific citations, review of citations in relevant primary articles, searches of services providing information on unpublished studies, contact with primary investigators and the ligation equipment manufacturer, and review of proceedings from pertinent scientific meetings. Study selection From 158 potentially relevant articles, duplicate independent review identified 7 relevant randomized trials that compared endoscopic ligation with sclerotherapy for the treatment of patients with bleeding esophageal varices. Data abstraction Independent, duplicate data abstraction of the population, intervention, outcome, and methodologic quality of the trials was done. Data synthesis Ligation therapy compared with sclerotherapy reduced the rebleeding rate (odds ratio, 0.52 [95% CI, 0.37 to 0.74]), the mortality rate (odds ratio, 0.67 [CI, 0.46 to 0.98]), and the rate of death due to bleeding (odds ratio, 0.49 [CI, 0.24 to 0.996]). Four patients would need to be treated with ligation instead of sclerotherapy to avert one rebleeding episode, and 10 would need to be treated with ligation instead of sclerotherapy to prevent one death. Esophageal strictures occurred less frequently with ligation (odds ratio, 0.10 [CI, 0.03 to 0.29]), but no significant differences were seen between treatments for pulmonary infections or bacterial peritonitis. Additionally, the number of endoscopic treatment sessions required to achieve variceal obliteration was lower with ligation than with sclerotherapy. Conclusions On the basis of lower rates of rebleeding, mortality, and complications and the need for fewer endoscopic treatments, ligation should be considered the endoscopic treatment of choice for patients with esophageal variceal bleeding.
590 citations
524 citations
01 Jan 1995
TL;DR: A 19 year-old woman who has had systemic lupus erythematosus diagnosed on the basis of a characteristic skin rash, arthritis, and renal disease is seeing an internal medicine resident in a rheumatology rotation.
Abstract: You are working as an internal medicine resident in a rheumatology rotation and are seeing a 19 year-old woman who has had systemic lupus erythematosus diagnosed on the basis of a characteristic skin rash, arthritis, and renal disease. A renal biopsy has shown diffuse proliferative nephritis. A year ago, her creatinine was 140 micromoles/litre, six months ago 180, and in a blood sample taken a week before this clinic visit, 220. Over the last year she has been taking prednisone, and over the last six months, cyclophosphamide, both in appropriate doses.
477 citations
TL;DR: While ICU health care workers consistently identify a number of patient factors as important in decisions to withdraw care, there is extreme variability, which may be explained in part by the values of individual health care providers.
Abstract: Objective. —To examine the attitudes of health care workers regarding the withdrawal of life support. Design. —Cross-sectional survey. Participants. —Attending staff, house staff, and intensive care unit (ICU) nurses in 37 Canadian university-affiliated hospitals. Main Outcome Measures. —Health care workers' ratings of the importance of 17 factors considered in the decision to withdraw life support, and their ratings of five levels of care ranging from comfort measures to intensive care in two of 12 different clinical scenarios. Results. —We surveyed 1361 respondents (149 of 167 potentially eligible ICU attending staff, 142 of 173 ICU house staff, and 1070 of 1455 ICU nurses, with response rates of 89%, 82% and 74%, respectively). The most important factors were likelihood of surviving the current episode, likelihood of long-term survival, premorbid cognitive function, and age of the patient. In choosing the level of care for the patient scenarios, the same option was chosen by more than 50% of respondents in only one of 12 scenarios; opposite extremes of care were chosen by more than 10% of the respondents in eight of 12 scenarios. Respondent characteristics affecting choices included the number of years since graduation, the city and province in which they worked, the number of beds in their ICU, and their assessment of the likelihood that they would withdraw life support in comparison with their colleagues (P Conclusions. —While ICU health care workers consistently identify a number of patient factors as important in decisions to withdraw care, there is extreme variability, which may be explained in part by the values of individual health care providers. (JAMA. 1995;273:703-708)
377 citations
TL;DR: Enteral nutrition is not started in all eligible ICU patients, and approximately half of those patients receiving enteral nutrition achieved tolerance of the regimen, and use of paralytic agents and the presence of high gastric residuals were associated with intolerance.
Abstract: ObjectivesTo describe current enteral nutrition-prescribing practices for critically ill patients, and to identify factors associated with initiation of, and tolerance to, enteral nutrition.DesignA prospective, cohort study.SettingTwo tertiary care medical-surgical intensive care units (ICU) in Onta
312 citations
TL;DR: While ICU health care workers consistently identify a number of patient factors as important in decisions to withdraw care, there is extreme variability, which may be explained in part by the values of individual health care providers.
Abstract: OBJECTIVE To examine the attitudes of health care workers regarding the withdrawal of life support. DESIGN Cross-sectional survey. PARTICIPANTS Attending staff, house staff, and intensive care unit (ICU) nurses in 37 Canadian university-affiliated hospitals. MAIN OUTCOME MEASURES Health care workers' ratings of the importance of 17 factors considered in the decision to withdraw life support, and their ratings of five levels of care ranging from comfort measures to intensive care in two of 12 different clinical scenarios. RESULTS We surveyed 1361 respondents (149 of 167 potentially eligible ICU attending staff, 142 of 173 ICU house staff, and 1070 of 1455 ICU nurses, with response rates of 89%, 82% and 74%, respectively). The most important factors were likelihood of surviving the current episode, likelihood of long-term survival, premorbid cognitive function, and age of the patient. In choosing the level of care for the patient scenarios, the same option was chosen by more than 50% of respondents in only one of 12 scenarios; opposite extremes of care were chosen by more than 10% of the respondents in eight of 12 scenarios. Respondent characteristics affecting choices included the number of years since graduation, the city and province in which they worked, the number of beds in their ICU, and their assessment of the likelihood that they would withdraw life support in comparison with their colleagues (P < .001 for all comparisons). CONCLUSIONS While ICU health care workers consistently identify a number of patient factors as important in decisions to withdraw care, there is extreme variability, which may be explained in part by the values of individual health care providers.
TL;DR: This article will show how to interpret the results and generalizability of a clinical decision analysis (Table), and decision trees are displayed graphically, oriented from left to right, with the decision to be analyzed on the left, the compared strategies in the center, and the clinical outcomes on the right.
Abstract: YOU RECALL from the first of our two articles concerning clinical decision analysis1that your patient is a middle-aged man with heart failure from an idiopathic dilated cardiomyopathy. You are trying to decide whether to recommend anticoagulation with warfarin to prevent systemic or pulmonary thromboembolism. Your literature search showed that no randomized clinical trials of warfarin for this use have been published. The search did discover a clinical decision analysis,2and in the first article, we showed you how to evaluate its validity. In this article, we will show you how to interpret the results and generalizability of a clinical decision analysis (Table). As shown in the Figure, decision trees are displayed graphically, oriented from left to right, with the decision to be analyzed on the left, the compared strategies in the center, and the clinical outcomes on the right. The square box, termed a "decision node," represents
Journal Article•
TL;DR: In the second of four articles, the authors discuss the "estimation" approach to interpreting study results, where in hypothesis testing, study results lead the reader to reject or accept a null hypothesis, in estimation the reader can assess whether a result is strong or weak, definitive or not.
Abstract: In the second of four articles, the authors discuss the "estimation" approach to interpreting study results. Whereas, in hypothesis testing, study results lead the reader to reject or accept a null hypothesis, in estimation the reader can assess whether a result is strong or weak, definitive or not. A confidence interval, based on the observed result and the size of the sample, is calculated. It provides a range of probabilities within which the true probability would lie 95% or 90% of the time, depending on the precision desired. It also provides a way of determining whether the sample is large enough to make the trial definitive. If the lower boundary of a confidence interval is above the threshold considered clinically significant, then the trial is positive and definitive, if the lower boundary is somewhat below the threshold, the trial is positive, but studies with larger samples are needed. Similarly, if the upper boundary of a confidence interval is below the threshold considered significant, the trial is negative and definitive. However, a negative result with a confidence interval that crosses the threshold means that trials with larger samples are needed to make a definitive determination of clinical importance.
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TL;DR: In the first of a series of four articles the authors explain the statistical concepts of hypothesis testing and p values, which may lead to an erroneous conclusion that an outcome is significant if the joint probability of the outcomes is not taken into account.
Abstract: In the first of a series of four articles the authors explain the statistical concepts of hypothesis testing and p values. In many clinical trials investigators test a null hypothesis that there is no difference between a new treatment and a placebo or between two treatments. The result of a single experiment will almost always show some difference between the experimental and the control groups. Is the difference due to chance, or is it large enough to reject the null hypothesis and conclude that there is a true difference in treatment effects? Statistical tests yield a p value: the probability that the experiment would show a difference as great or greater than that observed if the null hypothesis were true. By convention, p values of less than 0.05 are considered statistically significant, and investigators conclude that there is a real difference. However, the smaller the sample size, the greater the chance of erroneously concluding that the experimental treatment does not differ from the control--in statistical terms, the power of the test may be inadequate. Tests of several outcomes from one set of data may lead to an erroneous conclusion that an outcome is significant if the joint probability of the outcomes is not taken into account. Hypothesis testing has limitations, which will be discussed in the next article in the series.
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TL;DR: The calculation of measures of association are shown and their usefulness in clinical decision making is discussed and both the absolute risk reduction and the number needed to treat reflect both the baseline risk and the relative risk reduction.
Abstract: In the third of a series of four articles the authors show the calculation of measures of association and discuss their usefulness in clinical decision making. From the rates of death or other "events" in experimental and control groups in a clinical trial, we can calculate the relative risk (RR) of the event after the experimental treatment, expressed as a percentage of the risk without such treatment. The absolute risk reduction (ARR) is the difference in the risk of an event between the groups. The relative risk reduction is the percentage of the baseline risk (the risk of an event in the control patients) removed as a result of therapy. The odds ratio (OR), which is the measure of choice in case-control studies, gives the ratio of the odds of an event in the experimental group to those in the control group. The OR and the RR provide limited information in reporting the results of prospective trials because they do not reflect changes in the baseline risk. The ARR and the number needed to treat, which tells the clinician how many patients need to be treated to prevent one event, reflect both the baseline risk and the relative risk reduction. If the timing of events is important--to determine whether treatment extends life, for example--survival curves are used to show when events occur over time.
TL;DR: While ICU health care workers consistently identify a number of patient factors as important in decisions to withdraw care, there is extreme variability, which may be explained in part by the values of individual health care providers.
Abstract: OBJECTIVE
To examine the attitudes of health care workers regarding the withdrawal of life support.
DESIGN
Cross-sectional survey.
PARTICIPANTS
Attending staff, house staff, and intensive care unit (ICU) nurses in 37 Canadian university-affiliated hospitals.
MAIN OUTCOME MEASURES
Health care workers' ratings of the importance of 17 factors considered in the decision to withdraw life support, and their ratings of five levels of care ranging from comfort measures to intensive care in two of 12 different clinical scenarios.
RESULTS
We surveyed 1361 respondents (149 of 167 potentially eligible ICU attending staff, 142 of 173 ICU house staff, and 1070 of 1455 ICU nurses, with response rates of 89%, 82% and 74%, respectively). The most important factors were likelihood of surviving the current episode, likelihood of long-term survival, premorbid cognitive function, and age of the patient. In choosing the level of care for the patient scenarios, the same option was chosen by more than 50% of respondents in only one of 12 scenarios; opposite extremes of care were chosen by more than 10% of the respondents in eight of 12 scenarios. Respondent characteristics affecting choices included the number of years since graduation, the city and province in which they worked, the number of beds in their ICU, and their assessment of the likelihood that they would withdraw life support in comparison with their colleagues (P < .001 for all comparisons).
CONCLUSIONS
While ICU health care workers consistently identify a number of patient factors as important in decisions to withdraw care, there is extreme variability, which may be explained in part by the values of individual health care providers.
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TL;DR: In considering regression and correlation, clinicians should pay more attention to the magnitude of the correlation or the predictive power of the regression than to whether the relation is statistically significant.
Abstract: Correlation and regression help us to understand the relation between variables and to predict patients' status in regard to a particular variable of interest. Correlation examines the strength of the relation between two variables, neither of which is considered the variable one is trying to predict (the target variable). Regression analysis examines the ability of one or more factors, called independent variables, to predict a patient's status in regard to the target or dependent variable. Independent and dependent variables may be continuous (taking a wide range of values) or binary (dichotomous, yielding yes-or-no results). Regression models can be used to construct clinical prediction rules that help to guide clinical decisions. In considering regression and correlation, clinicians should pay more attention to the magnitude of the correlation or the predictive power of the regression than to whether the relation is statistically significant.
TL;DR: Abuse, discrimination, and homophobia are prevalent in the internal medicine workplace and a direct, progressive, multidisciplinary approach is necessary to label and address these problems.
Abstract: OBJECTIVE: To identify the frequency of psychological and emotional abuse, gender discrimination, verbal sexual harassment, physical sexual harassment, physical assault, and homophobia experienced by general internists. DESIGN: Cross-sectional survey. SETTING: Canadian general internal medicine practices. RESULTS: The overall response rate was 70.6% (984/1,393); the 501 respondents who classified themselves as general internists were studied. Three-fourths of the internists experienced psychological and emotional abuse at the hands of patients, and 38% of the women and 26% of the men experienced physical assault by patients. The majority of the female internists experienced gender discrimination by patients (67%) and by physician peers (56%). Forty-five percent of the women experienced verbal sexual harassment by patients, and 22% experienced physical sexual harassment by patients. The male internists experienced verbal sexual harassment from nurses slightly more often than the female internists did (19% vs 13%, p>0.05). Verbal sexual harassment by male colleagues was reported by 35% of the female internists, and physical sexual harassment was reported by 11%. Approximately 40% of general internists reported homophobic remarks by both health care team members and patients. CONCLUSIONS: Abuse, discrimination, and homophobia are prevalent in the internal medicine workplace. A direct, progressive, multidisciplinary approach is necessary to label and address these problems.
TL;DR: Although the good level of overall agreement suggests that CT provides useful information in the evaluation of mediastinal lymph node size, the disagreement was sufficient that it likely contributes to suboptimal sensitivity and specificity of CT in detecting tumor spread reported in previous studies.
TL;DR: A benefit-risk ratio is proposed that quantifies for a new therapy how many therapeutic events will be achieved for each adverse event incurred and is illustrated using data from the GUSTO trial comparing tissue plasminogen activator and streptokinase in the management of patients with acute myocardial infarction.
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TL;DR: The findings suggest that general internists want to take responsibility for revitalizing this discipline and help to promote action that will improve professional satisfaction in the area of clinical responsibilities, teaching, research and interpersonal issues.
Abstract: OBJECTIVES: To explore the importance of and satisfaction with clinical responsibilities, teaching, research and interpersonal issues among general internists; to understand the barriers to satisfaction in these domains and the usefulness of potential solutions to these problems. DESIGN: Cross-sectional survey conducted from November 1992 to June 1994. SETTING: Ontario. PARTICIPANTS: General internists who were fellows of the Royal College of Physicians and Surgeons of Canada and members of the Ontario Medical Association. Of 1192 physicians, 1007 (84.5%) returned a completed questionnaire; only the 199 who devoted at least 50% of their time to the practice of general internal medicine were included in this analysis. RESULTS: The respondents were satisfied with their primary role as clinicians dealing with complex, undifferentiated problems caring for the total patient and providing consultation. Guidelines for the referral of patients to general internists, computerization of test results, recruitment of general internal medicine fellows and more confidence in the future of general internal medicine were some of the solutions considered likely to increase professional satisfaction. The respondents involved in teaching suggested additional solutions, such as an opportunity to improve their teaching and evidence-based medicine skills and a greater recognition for their teaching efforts. Few of the general internists conducted research, barriers included lack of personal and project funding, and pressure to generate clinical earnings. In the domain of professional interpersonal issues, women were significantly more likely than men to rate having a mentor, peer support groups, ongoing career counselling, promotion and tenure guidelines for parental leave, availability of on-site day care, addressing gender discrimination and adoption of gender-neutral language as likely to improve the work environment. CONCLUSIONS: The primary role of general internists is that of patient-centred clinician. Our findings suggest that general internists want to take responsibility for revitalizing this discipline. The potential solutions generated in this survey may help to promote action that will improve professional satisfaction in the area of clinical responsibilities, teaching, research and interpersonal issues.
TL;DR: The results of three case series and two small randomised clinical trials indicate that a pressure-limited ventilation strategy aimed to reduce barotrauma may improve outcomes in patients with acute lung injury.
Abstract: Purpose: To review critically the literature on pulmonary barotrauma in mechanically ventilated patients. Methods: Data sources included MEDLINE and citation lists of relevant articles. Articles investigating the aetiology or prevention of pulmonary barotrauma were critically evaluated according to published guidelines. Results: Experimental animal studies and observational clinical studies consistently demonstrate that the high airway pressures and large tidal volumes associated with conventional modes of mechanical ventilation are major contributors to lung injury. Animal studies establish the correct temporal relationship and demonstrate a biological gradient. Observational clinical studies demonstrate an increased risk of barotrauma in the setting of acute lung injury. The results of three case series and two small randomised clinical trials indicate that a pressure-limited ventilation strategy aimed to reduce barotrauma may improve outcomes in patients with acute lung injury. Conclusions: Pulmonary b...
TL;DR: In this document, the development and use of general intensive care unit admission severity of illness scoring systems are critically reviewed.
Abstract: In this document we critically review the development and use of general intensive care unit admission severity of illness scoring systems. Data sources for this review included a computerized bibliographic search and published proceedings from relevant conferences in critical care medicine. Current
TL;DR: The epidemiology, pathogenesis, clinical manifestations and sequelae of acute organophosphate intoxication are reviewed and treatment aims at decontamination, muscarinic and nicotinic antagonism, regeneration of acetylcholinesterase and supportive therapy.
Abstract: Organophosphates are irreversible acetylcholinesterase inhibitors. Intoxication with these compounds is a global health concern. Acute manifestations include muscarinic, nicotinic and central nervous system signs and symptoms. Diagnosis requires a high clinical index of suspicion. Treatment aims at decontamination, muscarinic and nicotinic antagonism, regeneration of acetylcholinesterase and supportive therapy. Subacute and chronic sequelae may occur following intoxication. The epidemiology, pathogenesis, clinical manifestations and sequelae of acute organophosphate intoxication are reviewed.
TL;DR: The mean heparin bolus and initial infusion rates were significantly lower than those suggested in the literature (p<0.01) and the AH rates were comparable to historical controls but suboptimal compared with the rates of 66% at 24 hours and 81% at 48 hours reported in association with hepar in nomogram use.
Abstract: To determine the adequacy of initial anticoagulation by intravenous heparin for patients who have deep venous thrombosis (DVT), and the factors that influence delayed anticoagulation, independent, duplicate chart review of 63 consecutive patients who had venography-proven DVT was conducted. Adequate heparinization (AH) was defined as an activated partial thromboplastin time (PTT) of more than 1.5 times the normal laboratory control. The proportions of patients achieving AH within 24 hours and 48 hours of initial heparin bolus were 46% and 62%, respectively. Patients who weighed more were less likely to achieve AH (p<0.05), while patients receiving care from the thromboembolism service were more likely to achieve AH (p<0.05). Low initial infusion rate was strongly but not significantly predictive of inadequate anti-coagulation (p=0.06). The mean heparin bolus and initial infusion rates were significantly lower than those suggested in the literature (p<0.01). The AH rates were comparable to historical controls but suboptimal compared with the rates of 66% at 24 hours and 81% at 48 hours reported in association with heparin nomogram use (p<0.05). A heparin nomogram is likely to achieve consistently higher rates of adequate heparinization.
TL;DR: The pioneering work of Dr Chalmers has helped to transform clinical research, has improved the quality of patient care, has informed health policy, and has generated lively debate, and the introduction of cumulative meta-analysis will no doubt have similar effects.
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