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Derek C Angus

Publications and source records attributed to Derek C Angus.

At least 19 recordsLinked to original sources
PubMed2007

Perceptions of safety culture vary across the intensive care units of a single institution.

OBJECTIVE: To determine whether safety culture factors varied across the intensive care units (ICUs) of a single hospital, between nurses and physicians, and to explore ICU nursing directors' perceptions of their personnel's attitudes. DESIGN: Cross-sectional surveys using the Safety Attitudes Questionnaire-ICU version, a validated, aviation industry-based safety culture survey instrument. It assesses culture across six factors: teamwork climate, perceptions of management, safety climate, stress recognition, job satisfaction, and work environment. SETTING: Four ICUs in one tertiary care hospital. SUBJECTS: All ICU personnel. MEASUREMENTS AND MAIN RESULTS: We conducted the survey from January 1 to April 1, 2003, and achieved a 70.2% response rate (318 of 453). We calculated safety culture factor mean and percent-positive scores (percentage of respondents with a mean score of > or =75 on a 0-100 scale for which 100 is best) for each ICU. We compared mean ICU scores by ANOVA and percent-positive scores by chi-square. Mean and percent-positive scores by job category were modeled using a generalized estimating equations approach and compared using Wald statistics. We asked ICU nursing directors to estimate their personnel's mean scores and generated ratios of their estimates to the actual scores.Overall, factor scores were low to moderate across all factors (range across ICUs: 43.4-74.9 mean scores, 8.6-69.4 percent positive). Mean and percent-positive scores differed significantly (p < .0083, Bonferroni correction) across ICUs, except for stress recognition, which was uniformly low. Compared with physicians, nurses had significantly lower mean working conditions and perceptions of management scores. ICU nursing directors tended to overestimate their personnel's attitudes. This was greatest for teamwork, for which all director estimates exceeded actual scores, with a mean overestimate of 16%. CONCLUSIONS: Significant safety culture variation exists across ICUs of a single hospital. ICU nursing directors tend to overestimate their personnel's attitudes, particularly for teamwork. Culture assessments based on institutional level analysis or director opinion may be flawed.

Analysis of Variance↗
PubMed2006

Informal caregiver burden among survivors of prolonged mechanical ventilation.

RATIONALE: Although caregiver burden is well described in chronic illness, few studies have examined burden among caregivers of survivors of critical illness. In existing studies, it is unclear whether the observed burden is a consequence of critical illness or of preexisting patient illness. OBJECTIVES: To describe 1-yr longitudinal outcomes for caregivers of patients who survived critical illness, and to compare depression risk between caregivers of patients with and without pre-intensive care unit (ICU) functional dependency. METHODS: Prospective, parallel, cohort study of survivors of prolonged (greater than 48 h) mechanical ventilation and their informal caregivers. Caregivers were divided into two cohorts on the basis of whether patients were functionally independent (n = 99, 59%), or dependent (n = 70, 41%) before admission. Functional dependency was defined as dependency in one or more activities of daily living or in three or more instrumental activities of daily living. Patient and caregiver outcomes were measured 2, 6, and 12 mo after mechanical ventilation initiation. MEASUREMENTS AND MAIN RESULTS: We studied three caregiver outcomes: depression risk, lifestyle disruption, and employment reduction. Most patients were male (59.8%), with a mean (SD) age of 56.6 (19.0) yr. Caregivers were mostly female (75.7%), with a mean (SD) age of 54.6 (14.7) yr. Prevalence of caregiver depression risk was high at all time points (33.9, 30.8, and 22.8%; p = 0.83) and did not vary by patient pre-ICU functional status. Lifestyle disruption and employment reduction were also common and persistent. CONCLUSIONS: Depression symptoms, lifestyle disruption, and employment reduction were common among informal caregivers of critical illness survivors. Depression risk was high regardless of patient pre-ICU functional status.

Caregivers↗
PubMed2006

RIFLE criteria for acute kidney injury are associated with hospital mortality in critically ill patients: a cohort analysis.

INTRODUCTION: The lack of a standard definition for acute kidney injury has resulted in a large variation in the reported incidence and associated mortality. RIFLE, a newly developed international consensus classification for acute kidney injury, defines three grades of severity--risk (class R), injury (class I) and failure (class F)--but has not yet been evaluated in a clinical series. METHODS: We performed a retrospective cohort study, in seven intensive care units in a single tertiary care academic center, on 5,383 patients admitted during a one year period (1 July 2000-30 June 2001). RESULTS: Acute kidney injury occurred in 67% of intensive care unit admissions, with maximum RIFLE class R, class I and class F in 12%, 27% and 28%, respectively. Of the 1,510 patients (28%) that reached a level of risk, 840 (56%) progressed. Patients with maximum RIFLE class R, class I and class F had hospital mortality rates of 8.8%, 11.4% and 26.3%, respectively, compared with 5.5% for patients without acute kidney injury. Additionally, acute kidney injury (hazard ratio, 1.7; 95% confidence interval, 1.28-2.13; P < 0.001) and maximum RIFLE class I (hazard ratio, 1.4; 95% confidence interval, 1.02-1.88; P = 0.037) and class F (hazard ratio, 2.7; 95% confidence interval, 2.03-3.55; P < 0.001) were associated with hospital mortality after adjusting for multiple covariates. CONCLUSION: In this general intensive care unit population, acute kidney 'risk, injury, failure', as defined by the newly developed RIFLE classification, is associated with increased hospital mortality and resource use. Patients with RIFLE class R are indeed at high risk of progression to class I or class F. Patients with RIFLE class I or class F incur a significantly increased length of stay and an increased risk of inhospital mortality compared with those who do not progress past class R or those who never develop acute kidney injury, even after adjusting for baseline severity of illness, case mix, race, gender and age.

Acute Kidney Injury↗
PubMed2006

The association of sepsis syndrome and organ dysfunction with mortality in emergency department patients with suspected infection.

STUDY OBJECTIVE: The critical care community has used standard criteria for defining the sepsis syndromes and organ dysfunction for more than 15 years; however, these criteria are not well validated in the emergency department (ED) setting. The study objectives in our ED population of patients admitted to the hospital are to determine the prevalence of the sepsis syndromes, quantify inhospital mortality and 1-year survival associated with the sepsis syndromes, and assess the inhospital and 1-year survival associated with organ dysfunctions. METHODS: This was a prospective, observational, cohort study from February 1, 2000, to February 1, 2001 in an urban university hospital ED with 50,000 annual visits. There were 3,102 (96% of eligible) consecutive adult patients (aged 18 years or older) with suspected infection (as indicated by the clinical decision to obtain a blood culture) who were enrolled. Patients were screened for systemic inflammatory response syndrome (SIRS) (2 or more indicators of inflammatory response), sepsis (SIRS plus suspected infection), severe sepsis (sepsis plus organ dysfunction), septic shock (sepsis plus hypotension refractory to an initial fluid challenge), and number of organs with acute dysfunction. Main outcome measure was inhospital and 1-year mortality. RESULTS: Overall inhospital mortality was 4.1% and 1-year mortality was 22%. The inhospital mortality rates were suspected infection without SIRS 2.1%, sepsis 1.3%, severe sepsis 9.2%, and septic shock 28%. Compared to suspected infection without SIRS, adjusted risks of inhospital mortality were severe sepsis (odds ratio [OR] 4.0; 95% confidence interval [CI] 2.6 to 6.3) and septic shock (OR 13.8; 95% CI 6.6 to 29). Severe sepsis (OR 2.2; 95% CI 1.8 to 2.6) and septic shock (OR 3.5; 95% CI 2.3 to 5.3) also predicted 1-year mortality. The presence of SIRS criteria alone had no prognostic value for either endpoint. Each additional organ dysfunction increased the adjusted 1-year mortality hazard by 82% (pulse rate: 1.82, 95% CI 1.7 to 2.0). CONCLUSION: Immediate identification of acute organ dysfunction in ED patients with suspected infection may help select patients at increased short- and long-term mortality risk. SIRS criteria offered no additional prognostic value, whereas each additional organ dysfunction increased the 1-year mortality risk.

Adult↗
PubMed2006

Methods to adjust for bias and confounding in critical care health services research involving observational data.

Observational data are often used for research in critical care. Unlike randomized controlled trials, where randomization theoretically balances confounding factors, studies involving observational data pose the challenge of how to adjust appropriately for the bias and confounding that are inherent when comparing two or more groups of patients. This paper first highlights the potential sources of bias and confounding in critical care research and then reviews the statistical techniques available (matching, stratification, multivariable adjustment, propensity scores, and instrumental variables) to adjust for confounders. Finally, issues that need to be addressed when interpreting the results of observational studies, such as residual confounding, causality, and missing data, are discussed.

Bias↗
PubMed2006

Intensive care unit quality improvement: a "how-to" guide for the interdisciplinary team.

OBJECTIVE: Quality improvement is an important activity for all members of the interdisciplinary critical care team. Although an increasing number of resources are available to guide clinicians, quality improvement activities can be overwhelming. Therefore, the Society of Critical Care Medicine charged this Outcomes Task Force with creating a "how-to" guide that focuses on critical care, summarizes key concepts, and outlines a practical approach to the development, implementation, evaluation, and maintenance of an interdisciplinary quality improvement program in the intensive care unit. DATA SOURCES AND METHODS: The task force met in person twice and by conference call twice to write this document. We also conducted a literature search on "quality improvement" and "critical care or intensive care" and searched online for additional resources. DATA SYNTHESIS AND OVERVIEW: We present an overview of quality improvement in the intensive care unit setting and then describe the following steps for initiating or improving an interdisciplinary critical care quality improvement program: a) identify local motivation, support teamwork, and develop strong leadership; b) prioritize potential projects and choose the first target; c) operationalize the measures, build support for the project, and develop a business plan; d) perform an environmental scan to better understand the problem, potential barriers, opportunities, and resources for the project; e) create a data collection system that accurately measures baseline performance and future improvements; f) create a data reporting system that allows clinicians and others to understand the problem; g) introduce effective strategies to change clinician behavior. In addition, we identify four steps for evaluating and maintaining this program: a) determine whether the target is changing with periodic data collection; b) modify behavior change strategies to improve or sustain improvements; c) focus on interdisciplinary collaboration; and d) develop and sustain support from the hospital leadership. We also identify a number of online resources to complement this overview. CONCLUSIONS: This Society of Critical Care Medicine Task Force report provides an overview for clinicians interested in developing or improving a quality improvement program using a step-wise approach. Success depends not only on committed interdisciplinary work that is incremental and continuous but also on strong leadership. Further research is needed to refine the methods and identify the most cost-effective means of improving the quality of health care received by critically ill patients and their families.

Advisory Committees↗
PubMed2006

Critical care delivery in the United States: distribution of services and compliance with Leapfrog recommendations.

OBJECTIVES: To describe the organization and distribution of intensive care unit (ICU) patients and services in the United States and to determine ICU physician staffing before the publication and dissemination of the Leapfrog Group ICU physician staffing recommendations. DESIGN AND SETTING: Stratified, weighted survey of ICU directors in the United States, performed as part of the Committee on Manpower for the Pulmonary and Critical Care Societies (COMPACCS) study. Using lenient definitions, we defined an ICU as "high intensity" if > or =80% of patients were cared for by a critical care physician (intensivist) and defined an ICU as compliant with Leapfrog if it was both high-intensity and providing some form of in-house physician coverage during all hours. SUBJECTS: Three hundred ninety-three ICU directors. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We obtained a 33.5% response rate (393/1,173). We estimated there were 5,980 ICUs in the United States, caring for approximately 55,000 patients per day, with at least one ICU in all acute care hospitals. The predominant reasons for admission were respiratory insufficiency, postoperative care, and heart failure. Most ICUs were combined medical-surgical ICUs (n = 3,865; 65%), were located in nonteaching, community hospitals (n = 4,245; 71%), and were in hospitals of <300 beds (n = 3,710; 62%). One in four ICUs were high-intensity (n = 1,578; 26%), half had no intensivist coverage (n = 3,183; 53%), and the remainder had at least some intensivist presence (n = 1,219; 20%). High-intensity units were more common in larger hospitals (p = .001) and in teaching hospitals (p < .001) and more likely to be surgical (p < .001) or trauma ICUs (p < .001). Few ICUs had any in-house physician coverage outside weekday daylight hours (20% during weekend days, 12% during weeknights, and 10% during weekend nights). Only 4% (n = 255) of all adult ICUs in the United States appeared to meet the full Leapfrog standards (a high-intensity ICU staffing pattern plus dedicated attending coverage during daytime plus dedicated coverage by any physician during nighttime). CONCLUSIONS: ICU services are widely distributed but heterogeneously organized in the United States. Although high-intensity ICUs have been associated previously with improved outcomes, they were infrequent in our study, especially in smaller hospitals, and virtually no ICU met the Leapfrog standards before their dissemination. These findings highlight the considerable challenge to any efforts designed to promote either 24-hr physician coverage or high-intensity model organization.

Adult↗
PubMed2006

How does lack of insurance affect use of intensive care? A population-based study.

OBJECTIVE: One in six Americans aged <65 yrs are without health insurance. Although lack of insurance is associated with reduced access to many health services, the relationship between lack of insurance and use of intensive care services is unclear. We sought to compare the use of intensive care by insured and uninsured populations. DESIGN: Retrospective population-based cross-sectional study of five U.S. states (Florida, Massachusetts, New Jersey, New York, and Virginia), analyzing use of hospital and intensive care unit (ICU) services by all residents of these states <65 yrs of age. Data sources included the five 1999 state hospital discharge databases and the 2000 U.S. Census Bureau Current Population Survey. SETTING: Nonfederal hospitals in the five states (all hospitalizations in these during 1999). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 39.3 million and 7.8 million individuals aged 0-64 yrs with and without insurance, respectively, in the five-state sample. The uninsured population was far less likely to be hospitalized (odds ratio [OR], 0.458; 95% confidence interval [CI], 0.456-0.460; p < .001) and to be admitted to the ICU (OR, 0.581, 95% CI: 0.576-0.587, p < .001). Differences persisted irrespective of age, gender, ethnicity, or reason for admission. Among those hospitalized, the uninsured were more likely to receive intensive care (OR, 1.24; 95% CI, 1.22-1.25; p < .01). Hospital mortality rates for patients admitted to the ICU ranged by age from 4.0% to 6.9% for the uninsured and from 2.7% to 5.5% for the insured (OR, 1.12-1.54; p < .01). CONCLUSIONS: Americans without insurance use ICU services less often than those with insurance, primarily because of decreased likelihood of hospital admission in the first place. Outcome is worse for those who are admitted to the ICU, possibly because they are sicker when they seek care.

Adolescent↗
PubMed2006

End-of-life care for the critically ill: A national intensive care unit survey.

OBJECTIVE: One in five Americans dies following treatment in an intensive care unit (ICU), and evidence indicates the need to improve end-of-life care for ICU patients. We conducted this study to elicit the views and experiences of ICU directors regarding barriers to optimal end-of-life care and to identify the type, availability, and perceived benefit of specific strategies that may improve this care. DESIGN: Self-administered mail survey. SETTING: Six hundred intensive care units. PARTICIPANTS: A random, nationally representative sample of nursing and physician directors of 600 adult ICUs in the United States. INTERVENTIONS: Mail survey. MEASUREMENTS AND MAIN RESULTS: We asked participants about barriers to end-of-life care (1 = huge to 5 = not at all a barrier), perceived benefit of strategies to improve end-of-life care, and availability of these strategies. From 468 ICUs (78.0% of sample), 590 ICU directors participated (406 nurses [65.1% response] and 184 physicians [31.7% response]). Respondents had a mean of 16.6 yrs (sd 7.6 yrs) of ICU experience. Important barriers to better end-of-life care included patient/family factors, including unrealistic patient/family expectations 2.5 (1.0), inability of patients to participate in discussions 2.7 (0.9), and lack of advance directives 2.9 (1.0); clinician factors, which included insufficient physician training in communication 2.9 (1.1) and competing demands on physicians' time 3.0 (1.1); and institution/ICU factors, such as suboptimal space for family meetings 3.5 (1.2) and lack of a palliative care service 3.4 (1.2). More than 80% of respondents rated 14 of 14 strategies as likely to improve end-of-life care, including trainee role modeling by experienced clinicians, clinician training in communication and symptom management, regular meetings of senior clinicians with families, bereavement programs, and end-of-life care quality monitoring. However, few of these strategies were widely available. CONCLUSIONS: Intensive care unit directors perceive important barriers to optimal end-of-life care but also universally endorse many practical strategies for quality improvement.

Attitude of Health Personnel↗
PubMed2006

Healthcare costs and long-term outcomes after acute respiratory distress syndrome: A phase III trial of inhaled nitric oxide.

OBJECTIVE: To determine the costs and long-term outcomes of acute respiratory distress syndrome (ARDS) in previously healthy adults. To determine whether treatment with inhaled nitric oxide affects these costs and outcomes. DESIGN: One-year follow-up of a randomized trial of inhaled nitric oxide. Hospital bills were collected, and follow-up was performed at hospital discharge, 6 months, and 1 year. SETTING: Forty-six U.S. centers. PATIENTS: Three hundred and eighty-five previously healthy adults with ARDS. INTERVENTIONS: Subjects were randomized to 5 ppm inhaled nitric oxide or placebo gas. MEASUREMENTS AND MAIN RESULTS: One-year survival was 67.8%, with no difference by treatment arm (67.3% vs. 68.3% for inhaled nitric oxide vs. placebo, p = .71). Hospital costs from enrollment to discharge were high and similar in the inhaled nitric oxide and placebo arms ($48,500 vs. $47,800, p = 0.8). There were also no differences in length of stay or Therapeutic Intervention Scoring System points. Almost half (43.4%) of subjects were discharged to another healthcare facility or to home with professional help, and 24.1% were readmitted in 6 months, with no differences between groups. At 1 year, survivors reported low quality of life with no differences by treatment arm (Quality of Well-Being score [range 0-1], 0.61 vs. 0.64 for inhaled nitric oxide vs. placebo, p = .11) and poor function with no differences by treatment arm (32.5% returned to </=5 points of baseline Activities of Daily Living [range 0-100], 63.3% returned to </=10 points, and the remaining 36.7% suffered a mean decrement of 27 points). CONCLUSIONS: ARDS, even in previously healthy adults, not only is followed by poor survival, quality of life, and function but also is associated with high costs of care and postdischarge resource use. Inhaled nitric oxide at 5 ppm had no effect on these outcomes.

Administration, Inhalation↗
PubMed2006

Designing clinical trials in acute lung injury/acute respiratory distress syndrome.

PURPOSE OF REVIEW: To review the implications of recent literature for clinical trial design in acute lung injury/acute respiratory distress syndrome (ARDS). RECENT FINDINGS: Refinement of acute lung injury/acute respiratory distress syndrome diagnostic criteria and study enrollment criteria, greater efforts to define usual care appropriately, and balancing of efficacy and effectiveness design principles will be key components of future trials. SUMMARY: Clinical trial design in acute lung injury/acute respiratory distress syndrome faces many challenges. Although we have learned much from past trials, persistent design dilemmas must be addressed for future trials.

Clinical Trials as Topic↗
PubMed2006

Racial variation in end-of-life intensive care use: a race or hospital effect?

OBJECTIVE: To determine if racial and ethnic variations exist in intensive care (ICU) use during terminal hospitalizations, and, if variations do exist, to determine whether they can be explained by systematic differences in hospital utilization by race/ethnicity. DATA SOURCE: 1999 hospital discharge data from all nonfederal hospitals in Florida, Massachusetts, New Jersey, New York, and Virginia. DESIGN: We identified all terminal admissions (N = 192,705) among adults. We calculated crude rates of ICU use among non-Hispanic whites, blacks, Hispanics, and those with "other" race/ethnicity. We performed multivariable logistic regression on ICU use, with and without adjustment for clustering of patients within hospitals, to calculate adjusted differences in ICU use and by race/ethnicity. We explored both a random-effects (RE) and fixed-effect (FE) specification to adjust for hospital-level clustering. DATA COLLECTION: The data were collected by each state. PRINCIPAL FINDINGS: ICU use during the terminal hospitalization was highest among nonwhites, varying from 64.4 percent among Hispanics to 57.5 percent among whites. Compared to white women, the risk-adjusted odds of ICU use was higher for white men and for nonwhites of both sexes (odds ratios [ORs] and 95 percent confidence intervals: white men = 1.16 (1.14-1.19), black men = 1.35 (1.17-1.56), Hispanic men = 1.52 (1.27-1.82), black women = 1.31 (1.25-1.37), Hispanic women =1.53 (1.43-1.63)). Additional adjustment for within-hospital clustering of patients using the RE model did not change the estimate for white men, but markedly attenuated observed differences for blacks (OR for men =1.12 (0.96-1.31), women = 1.10 (1.03-1.17)) and Hispanics (OR for men =1.19 (1.00-1.42), women = 1.18 (1.09-1.27)). Results from the FE model were similar to the RE model (OR for black men = 1.10 (0.95-1.28), black women = 1.07 (1.02-1.13) Hispanic men = 1.17 (0.96-1.42), and Hispanic women = 1.14 (1.06-1.24)) CONCLUSIONS: The majority of observed differences in terminal ICU use among blacks and Hispanics were attributable to their use of hospitals with higher ICU use rather than to racial differences in ICU use within the same hospital.

Adult↗
PubMed2006

Predicting late anemia in critical illness.

INTRODUCTION: Identifying critically ill patients most likely to benefit from pre-emptive therapies will become increasingly important if therapies are to be used safely and cost-effectively. We sought to determine whether a predictive model could be constructed that would serve as a useful decision support tool for the pre-emptive management of intensive care unit (ICU)-related anemia. METHODS: Our cohort consisted of all ICU patients (n = 5,170) admitted to a large tertiary-care academic medical center during the period from 1 July 2000 to 30 June 2001. We divided the cohort into development (n = 3,619) and validation (n = 1,551) sets. Using a set of demographic and physiologic variables available within six hours of ICU admission, we developed models to predict patients who either received late transfusion or developed late anemia. We then constructed a point system to quantify, within six hours of ICU admission, the likelihood of developing late anemia. RESULTS: Models showed good discrimination with receiver operating characteristic curve areas ranging from 0.72 to 0.77, although predicting late transfusion was consistently less accurate than predicting late anemia. A five-item point system predicted likelihood of late anemia as well as existing clinical trial inclusion criteria but resulted in pre-emptive intervention more than two days earlier. CONCLUSION: A rule-based decision support tool using information available within six hours of ICU admission may lead to earlier and more appropriate use of blood-sparing strategies.

Adult↗
PubMed2006

Genetics and proteomics: deciphering gene association studies in critical illness.

There is considerable interest in understanding genetic determinants of critical illness to improve current risk stratification models, provide individualized therapies, and improve our current understanding of disease mechanisms. This review provides a broad overview of genetic nomenclature, different study designs, and problems unique to each of these study designs in critical illnesses. Well designed genetic studies with careful attention to these issues during the planning phase, use of rigorous statistical methods during analysis, and replication of these results in different cohorts will lead to more robust results and improved understanding of genetics of critical care.

Critical Illness↗