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Gordon D Rubenfeld

Publications and source records attributed to Gordon D Rubenfeld.

At least 19 recordsLinked to original sources
PubMed2006

Hypercapnic acidosis and mortality in acute lung injury.

OBJECTIVE: We tested the hypothesis that hypercapnic acidosis is associated with reduced mortality rate in patients with acute lung injury independent of changes in mechanical ventilation. DESIGN: Secondary analysis of randomized clinical trial data using hypothesis-driven multivariate logistic regression. SETTING: Randomized, multiple-center trial (n = 861) comparing 12 mL/kg to 6 mL/kg predicted body weight tidal volumes previously published by the National Institutes of Health Acute Respiratory Distress Syndrome (ARDS) Network. PATIENTS: Acute lung injury patients enrolled in a randomized, multiple-center trial (n = 861). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The adjusted odds ratio and 95% confidence intervals (CI) for 28-day mortality rate associated with hypercapnic acidosis defined as day 1 pH <7.35 and Pa(CO2) >45 mm Hg were 0.14 (95% CI 0.03-0.70, p = .016) in the 12 mL/kg predicted body weight tidal volume group and 1.18 (95% CI 0.59-2.35, p = .639) in the 6 mL/kg predicted body weight tidal volume group. Other definitions of hypercapnic acidosis spanning a range of magnitudes suggest a dose-response association between hypercapnic acidosis and 28-day mortality in the 12 mL/kg predicted body weight tidal volume group. None of our definitions of hypercapnic acidosis were associated with reduction in 28-day mortality in the 6 mL/kg predicted body weight tidal volume group. CONCLUSIONS: Hypercapnic acidosis was associated with reduced 28-day mortality in the 12 mL/kg predicted body weight tidal volume group after controlling for comorbidities and severity of lung injury. These results are consistent with a protective effect of hypercapnic acidosis against ventilator-associated lung injury that was not found when the further ongoing injury was reduced by 6 mL/kg predicted body weight tidal volumes.

Acidosis, Respiratory↗
PubMed2006

Acute lung injury in patients with subarachnoid hemorrhage: incidence, risk factors, and outcome.

OBJECTIVE: Pulmonary complications account for significant morbidity and mortality following aneurysmal subarachnoid hemorrhage; however, the effect of acute lung injury is largely unknown. The goal of this study was to determine the incidence of acute lung injury in a large cohort of patients with subarachnoid hemorrhage as well as determine the risk factors for acute lung injury and its effect on mortality and length of stay. Ventilator management was analyzed to determine the proportion of patients with subarachnoid hemorrhage and acute lung injury who a received a low-tidal volume ventilation strategy. DESIGN: Retrospective cohort study. SETTING: University-affiliated county hospital in Seattle, WA. PATIENTS: Six-hundred and twenty patients with aneurysmal subarachnoid hemorrhage documented on computed tomography or angiography. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: One-hundred and seventy patients met criteria for acute lung injury (incidence, 27%; 95% confidence interval, 24-31%). On multivariate analysis, severity of illness, clinical grade of hemorrhage, packed red blood cell transfusions, and severe sepsis in the intensive care unit were independently associated with development of acute lung injury. After adjustment for important confounders, development of acute lung injury was associated with a statistically significant increase in hospital mortality (odds ratio, 1.63; 95% confidence interval, 1.03-2.57). Acute lung injury was also independently associated with an increased intensive care unit length of stay (15%, 95% confidence interval, 5-27%). Thirty percent of patients with acute lung injury received low tidal volume ventilation. Patients receiving low tidal volume ventilation had worse oxygenation and higher positive end-expiratory pressure requirements compared with those who did not, but there were no significant differences in arterial pH or Pco2. CONCLUSIONS: Acute lung injury is common in patients with subarachnoid hemorrhage and is independently associated with a worse clinical outcome. Research is needed to determine the causes of acute lung injury in this population and whether these patients are candidates for evidence-based ventilator strategies to reduce mortality.

Adult↗
PubMed2006

Rationing in the intensive care unit.

BACKGROUND: Critical care services represent a large and growing proportion of health care expenditures. Limiting the magnitude of these costs while maintaining a just allocation of these services will require rationing. We define rationing as "the allocation of healthcare resources in the face of limited availability, which necessarily means that beneficial interventions are withheld from some individuals." Although some have maintained that rationing of health care is unethical, we argue that rationing is not only unavoidable but essential to ensuring the ethical distribution of medical goods and services. PRINCIPAL FINDINGS: Intensivists have little to guide them in the rationing of critical care services. We have developed a taxonomy of the rationing choices faced by intensivists as a framework for ethical analysis. This taxonomy divides rationing decisions into three categories. First are those rationing decisions that may be justified by external constraints (such as not prescribing a potentially beneficial medication because it is not available on the hospital formulary). Second are those that may be justified by reference to clinical guidelines (as, for example, not prescribing a potentially beneficial medication because a valid guideline recommends treatment with a less expensive alternative). Third are those that are justified by individual clinical judgment (such as choosing which of two patients should be admitted into the last ICU bed, in the absence of any evidence-based guidance). Judgments made on the basis of clinical judgment deserve particular scrutiny, since they may mask unethical prejudices or bias. CONCLUSIONS: Although this taxonomy does not by itself determine which decisions are ethical, it does clarify the type of evidence that is appropriate to supporting the decision that is made. Additional work is needed to elucidate how both empirical evidence and ethical analysis can further inform the rationing decisions that arise in the taxonomy described here.

Health Care Rationing↗
PubMed2005

Incidence and outcomes of acute lung injury.

BACKGROUND: Acute lung injury is a critical illness syndrome consisting of acute hypoxemic respiratory failure with bilateral pulmonary infiltrates that are not attributed to left atrial hypertension. Despite recent advances in our understanding of the mechanism and treatment of acute lung injury, its incidence and outcomes in the United States have been unclear. METHODS: We conducted a prospective, population-based, cohort study in 21 hospitals in and around King County, Washington, from April 1999 through July 2000, using a validated screening protocol to identify patients who met the consensus criteria for acute lung injury. RESULTS: A total of 1113 King County residents undergoing mechanical ventilation met the criteria for acute lung injury and were 15 years of age or older. On the basis of this figure, the crude incidence of acute lung injury was 78.9 per 100,000 person-years and the age-adjusted incidence was 86.2 per 100,000 person-years. The in-hospital mortality rate was 38.5 percent. The incidence of acute lung injury increased with age from 16 per 100,000 person-years for those 15 through 19 years of age to 306 per 100,000 person-years for those 75 through 84 years of age. Mortality increased with age from 24 percent for patients 15 through 19 years of age to 60 percent for patients 85 years of age or older (P<0.001). We estimate that each year in the United States there are 190,600 cases of acute lung injury, which are associated with 74,500 deaths and 3.6 million hospital days. CONCLUSIONS: Acute lung injury has a substantial impact on public health, with an incidence in the United States that is considerably higher than previous reports have suggested.

Adolescent↗
PubMed2005

Clinical trial participants compared with nonparticipants in cystic fibrosis.

RATIONALE: The randomized clinical trial has been an important tool for expanding our knowledge of disease. This study is the first to compare trial participants to the entire eligible population. METHODS: We performed a cohort analysis using data from the Cystic Fibrosis Foundation Registry database between 1992 and 1998. MEASUREMENTS AND MAIN RESULTS: There were 8,735 patients older than 6 yr followed for the entire period. Of the patients, 2,635 patients (30.2%) were enrolled in at least 1 of 32 Institutional Review Board-approved clinical trials, with an average annual participation rate of 7%. Patients enrolled in clinical trials had more advanced disease as judged by FEV(1)% predicted (68 vs. 77%, p < 0.001), higher rates of Pseudomonas aeruginosa infection (71 vs. 65%, p < 0.01), and were more likely to have private insurance (odds ratio [OR], 1.25; 95% confidence interval [CI], 1.14-1.37) and be white (OR, 1.98; 95% CI, 1.44-2.70). No sex differences were noted. Despite the worse clinical status at baseline, clinical trial participants had a lower average annual rate of decline in lung function (1.33%/yr; 95% CI, 1.20, 1.46; compared with 1.52%; 95% CI, 1.43-1.60). CONCLUSIONS: These results show that the overall participation rate is very high. Despite more advanced disease at baseline, lung function decline was lower in trial participants; the cause of this difference is unclear. The differences seen in insurance status are concerning. Efforts should be made to ensure adequate representation from different social demographic groups.

Adolescent↗
PubMed2005

Missed opportunities during family conferences about end-of-life care in the intensive care unit.

BACKGROUND: Improved communication with family members of critically ill patients can decrease the prolongation of dying in the intensive care unit (ICU), but few data exist to guide the conduct of this communication. OBJECTIVE: Our objective was to identify missed opportunities for physicians to provide support for or information to family during family conferences. METHODS: We identified ICU family conferences in four hospitals that included discussions about withdrawing life support or delivery of bad news. Fifty-one conferences were audiotaped, including 214 family members. Thirty-six physicians led the conferences and some physicians led more than one. We used qualitative methods to identify and categorize missed opportunities, defined as an occurrence when the physician had an opportunity to provide support or information to the family and did not. MAIN RESULTS: Fifteen family conferences (29%) had missed opportunities identified. These fell into three categories: opportunities to listen and respond to family; opportunities to acknowledge and address emotions; and opportunities to pursue key principles of medical ethics and palliative care, including exploration of patient preferences, explanation of surrogate decision making, and affirmation of nonabandonment. The most commonly missed opportunities were those to listen and respond, but examples from other categories suggest value in being aware of these opportunities. CONCLUSIONS: Identification of missed opportunities during ICU family conferences provides suggestions for improving communication during these conferences. Future studies are needed to demonstrate whether addressing these opportunities will improve quality of care.

Adult↗
PubMed2005

Estimating sample size in critical care clinical trials.

Estimating the required sample size for a study is necessary during the design phase to ensure that it will have maximal efficiency to answer the primary question of interest. Clinicians require a basic understanding of the principles underlying sample size calculation to interpret and apply research findings. This article reviews the critical components of sample size calculation, including the selection of a primary outcome, specification of the acceptable types I and II error rates, identification of the minimal clinically important difference, and estimation of the error associated with measuring the primary outcome. The relationship among confidence intervals, precision, and study power is also discussed.

Bias↗
PubMed2005

Publications and extramural activities of general internal medicine and medicine subspecialty clinician-educators: a multicenter study.

PURPOSE: Generalist clinician-educators may have more difficulty than specialists satisfying common promotion criteria (peer-reviewed publication and extramural reputation). This study compared publication rates and participation in extramural activities among subspecialist and generalist clinician-educators, and sought to determine the views of clinician-educators on the use of publication and reputation in determining their promotion. METHOD: A cross-sectional questionnaire was delivered to 526 clinician-educators identified by the chairs at ten randomly selected U.S. medical schools in 2002. RESULTS: A total of 270 clinician-educators responded. Medicine subspecialist clinician-educators reported more peer-reviewed publications than did general internal medicine (GIM) faculty (mean 26.4 versus 10.2, p < .003). Independent predictors of having a greater number of peer-reviewed publications were subspecialty membership (p < .01), less time spent in clinic (p < .01), focus of scholarship (p = .01), academic rank (p < .01), higher quartile of National Institutes of Health funding received by respondent's department (p < .01), and years on faculty (p = .03). A greater proportion of GIM faculty reported spending most of their protected time on scholarly activities less amenable to publication (p = .05). A greater proportion of subspecialists felt peer-reviewed publication should be required for promotion (p < .01), but a minority of both groups felt this should necessarily entail original research. CONCLUSION: Subspecialist clinician-educators generate significantly more peer-reviewed publications than do their GIM colleagues. clinician-educators hold diverse views on the role of publication and reputation in determining their promotion.

Academic Medical Centers↗
PubMed2005

Intrinsic positive end-expiratory pressure in Acute Respiratory Distress Syndrome (ARDS) Network subjects.

OBJECTIVE: We tested the hypothesis that subjects randomized to the 6 mL/kg predicted body weight tidal volume study group of the National Institutes of Health Acute Respiratory Distress Syndrome (ARDS) Network study had higher levels of intrinsic positive end-expiratory pressure (PEEP) than subjects randomized to the 12 mL/kg predicted body weight tidal volume study group. DESIGN: Secondary analysis of a subgroup from a randomized controlled trial. SETTING: Hospitals located in San Francisco, CA, and Seattle, WA. PATIENTS: Eighty-four patients enrolled in the ARDS Network tidal volume trial in San Francisco, CA, and Seattle, WA, with records of measurement of intrinsic PEEP. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Intrinsic PEEP was assessed a median of six times over the first 48 hrs of ARDS Network protocol ventilation in study subjects, with no significant difference in number of measurements between subjects randomized to the tidal volume protocol of 6 mL/kg compared with 12 mL/kg. We found that intrinsic PEEP was higher among subjects randomized to the 6 mL/kg protocol, with a median intrinsic PEEP of 1.3 cm H2O (interquartile range, 0-3.1 cm H2O), compared with a median intrinsic PEEP of 0.5 cm H2O (interquartile range, 0-1.5 cm H2O) among subjects randomized to 12 mL/kg (p = .029). There was no difference in total PEEP between the study groups. CONCLUSIONS: In a subgroup of ARDS Network subjects, intrinsic PEEP was statistically significantly higher in subjects randomized to the 6 mL/kg protocol than those in the 12 mL/kg study group. The amount of intrinsic PEEP was very low in both study groups, and difference of median intrinsic PEEP between the groups was <1 cm H2O. It is unlikely that the difference in intrinsic PEEP between the study groups was clinically important in the ARDS Network study of low tidal volume ventilation.

Adult↗
PubMed2005

Low tidal volume ventilation does not increase sedation use in patients with acute lung injury.

OBJECTIVE: Low tidal volume ventilation is associated with reduced mortality in patients with acute lung injury, yet concerns exist about patient comfort and the levels of sedation and analgesia required during its use. We compared the doses and duration of sedatives and opioid analgesics in patients receiving low vs. traditional tidal volumes at our institution. DESIGN: Secondary analysis of a randomized clinical trial. SETTING: University-affiliated county hospital in Seattle, WA. PATIENTS: Sixty-one patients with acute lung injury enrolled in the National Heart, Lung and Blood Institute's ARDS Network tidal volume trial. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Thirty-three patients were randomized to the lower tidal volume arm (6 mL/kg of predicted body weight) and 28 patients were randomized to the higher tidal volume arm (12 mL/kg of predicted body weight). There were no significant differences in the percentage of study days patients received sedatives, opioids, or neuromuscular blockade. When specific study days were examined, there were no significant differences in the proportion of patients receiving benzodiazepines, propofol, haloperidol, and opioids on days 1, 2, 3, and 7 of mechanical ventilation, nor were there differences in the doses of benzodiazepines and opioids on those days. CONCLUSIONS: At our institution, low tidal volume ventilation was not associated with increased dose or duration of sedatives in patients with acute lung injury. Sedation administration should not be considered a barrier to implementing a lung-protective ventilation strategy.

Adult↗
PubMed2005

Causes and timing of death in patients with ARDS.

BACKGROUND: Since the early 1980s, case fatality of patients with ARDS has decreased, and explanations are unclear. DESIGN AND METHODS: Using identical definitions of ARDS and organ failure, we analyzed consecutive cohorts of patients meeting syndrome criteria at our institution in 1982 (n = 46), 1990 (n = 112), 1994 (n = 99), and 1998 (n = 205) to determine causes and timing of death. RESULTS: Overall case fatality has decreased from 68% in 1981-1982 to a low of 29% in 1996, plateauing since the mid-1990s (p = 0.001 for trend). Sepsis syndrome with multiple organ failure remains the most common cause of death (30 to 50%), while respiratory failure causes a small percentage (13 to 19%) of deaths. The distribution of causes of death has not changed over time. There was no change in the timing of death during the study periods: 26 to 44% of deaths occurred early (< 72 h after ARDS onset), and 56 to 74% occurred late (> 72 h after ARDS onset). However, the increased survival over the past 2 decades is entirely accounted for by patients who present with trauma and other risk factors for their ARDS, while survival for those patients whose risk factor is sepsis has not changed. Additionally, withdrawal of life support in these patients is now occurring at our institution significantly more frequently than in the past, and median time until death has decreased in patients who have support withdrawn. CONCLUSIONS: While these results do not explain the overall case fatality decline in ARDS, they do indicate that sepsis syndrome remains the leading cause of death and suggest that future therapies to improve survival be targeted at reducing the complications of sepsis.

Adolescent↗
PubMed2004

Clinical issues and research in respiratory failure from severe acute respiratory syndrome.

The National Heart, Lung, and Blood Institute, along with the Centers for Disease Control and Prevention and the National Institute of Allergy and Infectious Diseases, convened a panel to develop recommendations for treatment, prevention, and research for respiratory failure from severe acute respiratory syndrome (SARS) and other newly emerging infections. The clinical and pathological features of acute lung injury (ALI) from SARS appear indistinguishable from ALI from other causes. The mainstay of treatments for ALI remains supportive. Patients with ALI from SARS who require mechanical ventilation should receive a lung protective, low tidal volume strategy. Adjuvant treatments recommended include prevention of venous thromboembolism, stress ulcer prophylaxis, and semirecumbent positioning during ventilation. Based on previous experience in Canada, infection control resources and protocols were recommended. Leadership structure, communication, training, and morale are an essential aspect of SARS management. A multicenter, placebo-controlled trial of corticosteroids for late SARS is justified because of widespread clinical use and uncertainties about relative risks and benefits. Studies of combined pathophysiologic endpoints were recommended, with mortality as a secondary endpoint. The group recommended preparation for studies, including protocols, ethical considerations, Web-based registries, and data entry systems.

Adrenal Cortex Hormones↗
PubMed2004

Attending to the lightness of numbers: toward the understanding of critical care epidemiology.

Most of the epidemiological studies in critical care do not express their results in terms of population burden of critical illness. This happens because the population at risk of critical illness is particularly difficult to estimate, once intensive care units (ICUs) receive patients from many sources. The study by Laupland in this issue of Critical Care provides a good estimate of the incidence of admission to ICUs in the Calgary Health Region. He considered the Calgary Health Region population as the denominator and explored the effects of a changing numerator according to the residency status (resident in Calgary or not) on the estimation of the burden of admission to the ICU. He demonstrated that if the residency status were not known, the incidence of admission to the ICU would have been overestimated by more than 50%. Furthermore, non-residents had a lower mortality despite higher Acute Physiology and Chronic Health Evaluation (APACHE) II and Therapeutic Intervention Scoring System (TISS) scores. There is tremendous variability in decisions to admit a patient to the ICU and the epidemiology of critical care is influenced by them in a subtle but inextricable way. An understanding of the population epidemiology of critical illness and the use of the ICU, the variations in these parameters, and factors that influence this variation is extremely important. The notable effect of a changing numerator on the estimation of the population burden of ICU admissions in the study by Laupland illustrates how fluid our estimates of disease incidence and mortality - the mainstays of epidemiology - can be.

APACHE↗
PubMed2004

Principles and practice of withdrawing life-sustaining treatments.

The clinician's responsibility to the patient does not end with a decision to limit medical treatment, but continues through the dying process. Every effort should be made to ensure that withdrawing life support occurs with the same quality and attention to detail as is routinely provided when life support is initiated. Approaching the withdrawal of life support as a medical procedure provides clinicians with a recognizable framework for their actions. Key steps in this process are identifying and communicating explicit shared goals for the process, approaching withdrawal of life-sustaining treatments asa medical procedure, and preparing protocols and materials to assure consistent care. Our hope is that adopting a more formal approach to this common procedure will improve the care of patients dying in intensive care units.

Analgesia↗