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Gordon D Rubenfeld

Publications and source records attributed to Gordon D Rubenfeld.

54 records · Page 3Linked to original sources

Changing pattern of ventilator settings in patients without acute lung injury: changes over 11 years in a single institution.

STUDY OBJECTIVES: To determine whether the widely accepted concept of using lower tidal volume (Vt) values in patients with ARDS or obstructive lung disease has affected the pattern of ventilator settings in mechanically ventilated patients who do not have one of these conditions. DESIGN AND PATIENTS: We performed a retrospective chart review of all patients who had experienced out-of-hospital cardiac arrest and had received ventilatory support for > or = 1 day at a university-affiliated county hospital during the years 1990, 1991, 1992, 1995, 1998, 1999, and 2000. RESULTS: In 139 such patients, the mean final Vt values used on the first day of mechanical ventilation were 11.7, 12.4, 11.3, 9.6, 9.7, 9.2, and 9.8 mL/kg in those years, respectively. Multivariate analysis revealed that increasing year (beta-coefficient = -0.24; p = 0.001) and the presence of pulmonary edema (beta-coefficient = -1.2; p = 0.001) were independent predictors of the use of lower Vt values. Patients managed with a low Vt (ie, < 10 mL/kg; mean [+/- SD] Vt, 8.4 +/- 1.3 mL/kg) had a significantly higher incidence of atelectasis than the patients who were managed with traditional, larger Vt values (ie, > or = 10 mL/kg; mean Vt, 11.8 +/- 1.5 mL/kg) [61.1% vs 36.7%, respectively; p = 0.02]. Multivariate analysis revealed that the mean Vt used on days 1, 2, and 3 (<10 mL/kg or > or = 10 mL/kg) was the only predictor of the development of atelectasis during the first 3 days of mechanical ventilation (odds ratio, 0.33; p = 0.015). There was no difference in the incidence of pneumonia, the number of days spent receiving mechanical ventilation, Pao(2)/fraction of inspired oxygen ratio, or respiratory system compliance between the low Vt group and the traditional Vt group. CONCLUSION: Currently, physicians at our hospital use lower Vt values than they have in the past. This is associated with the increase in the incidence of atelectasis in the patients who received ventilation using low Vt values.

Aged↗

Translating clinical research into clinical practice in the intensive care unit: the central role of respiratory care.

Critical care is entering a phase of rapid introduction of treatments that have demonstrated efficacy for reducing mortality and morbidity. Until recently the principal question facing intensivists was "Does this treatment work?" Though that question is still important, we now must address the same challenges other fields, notably cardiology, face in.

Biomedical Research↗

Surveys: an introduction.

Surveys are a valuable research tool for studying the knowledge, attitudes, and behavior of a study population. This article explores quantitative analyses of written questionnaires as instruments for survey research. Obtaining accurate and precise information from a survey requires minimizing the possibility of bias from inappropriate sampling or a flawed survey instrument, and this article describes strategies to minimize sampling bias by increasing response rates, comparing responders to nonresponders, and identifying the appropriate sampling population. It is crucial that the survey instrument be valid, meaning that it actually measures what the investigator intends it to measure. In developing a valid survey instrument, it can be useful to adapt survey instruments that were developed by other researchers and to conduct extensive pilot-testing of your survey instrument.

Bias↗

Is SARS just ARDS?

Explore the source record for details and available documents.

Diagnosis, Differential↗

Improving care for patients dying in the intensive care unit.

It is impossible for ICU clinicians to avoid caring for dying patients and their families. For many, this is an extremely rewarding aspect of their clinical practice. There is ample evidence that there is room to improve the care of patients who are near death in the ICU. Despite the considerable holes in our knowledge about optimal care of dying critically ill patients, there is considerable agreement on the general principles of caring for these patients and about how to measure the outcomes of palliative care in the ICU. Practical approaches to improving the quality of end-of-life care exist and should be implemented.

Humans↗

Epidemiology of acute lung injury.

OBJECTIVE: To review the epidemiology of acute lung injury (ALI) with particular emphasis on its effect on public health. DATA SOURCES: Published studies on the definitions, incidence, and outcomes of ALI. DATA SUMMARY: ALI is a syndrome of acute hypoxemic respiratory failure that is not primarily cardiac in origin. The diagnostic criteria for the syndrome have not been well studied for their reliability or validity. The lack of a gold standard for the diagnosis of ALI is a challenge to clinical investigation. Recent data on the incidence of ALI (20-50 cases/105 person-years) indicate that it is more common than previous estimates for the incidence of acute respiratory distress syndrome (3-8 cases/105 person-years). There is conflicting evidence as to whether the mortality rate in the broader patient population with ALI is different from the mortality rate in acute respiratory distress syndrome. Mortality attributable to and associated with ALI in the United States is comparable to HIV infection, breast cancer, and asthma. Morbidity from impaired cognitive function, functional status, and psychiatric complications has been reported in survivors of ALI. CONCLUSIONS: Recent studies of the epidemiology of ALI have reported higher incidence rates for this syndrome than previously described. The mortality and morbidity rates associated with ALI are considerable, with significant impact on public health.

Epidemiologic Methods↗

Lung-protective ventilation strategies in acute lung injury.

OBJECTIVES: To review the challenges of providing mechanical ventilatory support for respiratory failure while avoiding ventilator-associated lung injury in patients with acute lung injury. To review the results of several randomized clinical trials of lung-protective ventilation strategies using conventional mechanical ventilators. DATA SOURCES: Published reports of clinical trials comparing clinical outcomes of patients with acute lung injury, randomized to mechanical ventilation with either a lung-protective or a control, conventional, standard, or traditional approach. DATA EXTRACTION AND SYNTHESIS: Lung-protective mechanical ventilation strategies are designed to prevent injury from overdistention by using lower tidal volumes and lower inspiratory pressures (volume- and pressure-limited ventilation) or injury from ventilation with atelectasis and alveolar flooding at end-expiration (open-lung ventilation). In one trial, clinical outcomes were better in the study group that received combined volume- and pressure-limited and open-lung strategies compared with the study group that received a conventional approach. Of four trials focusing on volume- and pressure-limited ventilation alone, three did not demonstrate improvements in clinical outcomes, whereas one demonstrated a substantial reduction in mortality and an increase in ventilator-free days. The different results in these four trials may be attributable to differences in tidal volumes between the study groups, chance variation, or differences in the management of respiratory acidosis. CONCLUSIONS: Evidence supports the use of a volume- and pressure-limited approach to mechanical ventilation in patients with acute lung injury. It is not yet clear whether the open-lung approach will further reduce mortality in patients receiving volume- and pressure-limited ventilation support.

Humans↗

Incidence of acute lung injury in the United States.

OBJECTIVE: Recent estimates of acute respiratory distress syndrome (ARDS) incidence have varied from 1.3 to 22 per 100,000 person years (105 person.years); the incidence of acute lung injury (ALI) has varied from 17.9 to 34 cases per 105 person.years. Potential reasons for this wide range include differences in the definition of the syndrome, in the populations sampled, and in the assumptions made to estimate incidence. We hypothesized that careful, prospective, protocol-driven case identification that included the milder hypoxemia criterion for ALI would yield incidence numbers greater than previously reported. DESIGN: Prospective cohort study with extrapolation to the U.S. population. SETTING: National Heart, Lung, and Blood Institute-sponsored ARDS Network composed of 20 hospitals. PATIENTS: As part of the National Institutes of Health-sponsored ARDS network, 20 hospitals prospectively identified patients with ALI from 1996 to 1999. Screening logs from this study were used to estimate ALI rates per intensive care unit (ICU) bed per year. We used the registry and data from the American Hospital Association to estimate the incidence of ALI in the United States. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The ALI per ICU bed incidence in the ARDS network registry varied from 0.7 to 5.8 cases of ALI per ICU bed per year with an average of 2.2 cases of ALI per ICU bed per year. We tested the robustness of the incidence estimate by performing a variety of sensitivity analyses. When we used the conservative assumptions that the ARDS network screening logs were complete at each of the participating hospitals and that ALI cases are limited to academic hospitals with > or =20 adult ICU beds, the incidence of ALI in adults in the United States is 22.4 cases per 105 person.years. Under the less conservative assumption that ALI cases occurred only at hospitals with > or =20 ICU beds, regardless of their academic status, the incidence of ALI in the United States is estimated at 64.2 cases per 105 person.years. CONCLUSIONS: Based on this analysis, which used prospective clinical trial screening data and conservative assumptions about where patients with ALI are cared for, the incidence of ALI in the United States appears to be higher than previously reported.

Humans↗

Effect of age on the development of ARDS in trauma patients.

STUDY OBJECTIVES: The purpose of this study was to determine the independent effect of age on the risk of developing ARDS in patients with trauma. DESIGN: Prospective cohort study. SETTING: Level I trauma center. MEASUREMENTS AND RESULTS: A total of 4,020 consecutive trauma patients who were > 12 years of age were identified through the Harborview Medical Center Trauma Registry over a 3-year period. During this time, 484 of the trauma patients (12%) developed ARDS, as identified by the Harborview Medical Center ARDS Registry. Patients who developed ARDS were, on average, older (mean [+/- SD] age, 44.0 +/- 18.8 vs 40.2 +/- 20.0 years, respectively; p < 0.0001) and had higher injury severity scores (23.7 +/- 11.3 vs 18.0 +/- 10.3, respectively; p < 0.0001) than trauma patients who did not develop ARDS. The maximum unadjusted odds ratio for developing ARDS was 2.93 (95% confidence interval, 1.91 to 4.50) for the group 60 to 69 years of age compared to the group 13 to 19 years of age. Patients aged > or = 80 years had an equal risk of developing ARDS compared to those age 13 to 19 years. CONCLUSIONS: Age demonstrated a complex relationship with risk for ARDS development. Older patients showed increasingly higher risks for ARDS development up to 60 to 69 years of age, when the risk for ARDS declined. We concluded that older patients are at significantly greater risk of developing ARDS when compared to younger patients, while the oldest patients may be at less risk.

Adolescent↗

The effect of pregnancy on survival in women with cystic fibrosis.

STUDY OBJECTIVES: Patients with cystic fibrosis (CF) are currently living to their fourth decade and are making reproductive decisions. Information concerning the reproductive health of women with CF has been limited to small or single-center studies. DESIGN: We conducted a matched parallel-cohort study to assess the impact of pregnancy on the survival of women with CF. PARTICIPANTS: A parallel-cohort study included all women > 12 years of age who were enrolled in the US Cystic Fibrosis Foundation National Patient Registry from 1985 to 1997. MEASUREMENTS AND RESULTS: Six hundred eighty of the 8,136 women in the cohort became pregnant. These 680 women were matched on an index year to 3,327 control women with CF. At the inception of entry into the cohort, women who reported pregnancy were more likely to have had a higher percentage of predicted FEV(1) (67.5% predicted vs 61.7% predicted, respectively; p < 0.001) and a higher weight (52.9 vs 46.4 kg, respectively; p < 0.001). Using Kaplan-Meier survival curves, the 10-year survival rate in pregnant women (77%; 95% confidence interval [CI], 71 to 82%) was higher than in those women who did not become pregnant (58%; 95% CI, 55 to 62%). A separate analysis, matching pregnant patients on FEV(1) percent predicted, age, Pseudomonas aeruginosa colonization, and pancreatic function, obtained similar results. Using Cox proportional hazard modeling to adjust for baseline age, FEV(1) percent predicted, weight, height, and pulmonary exacerbation rate per year, pregnancy was not associated with an increase risk of death. Pregnancy was not harmful in any subgroup including patients with FEV(1) < 40% of predicted or diabetes mellitus. CONCLUSIONS: Women with CF who became pregnant were initially healthier and had better 10-year survival rates than women with CF who did not become pregnant. After adjustment for the initial severity of illness, women who became pregnant did not have a significantly shortened survival.

Adult↗

Cost and incidence of social comorbidities in low-risk patients with community-acquired pneumonia admitted to a public hospital.

CONTEXT: There are up to 1 million patients treated in acute-care hospitals for community-acquired pneumonia (CAP), with an estimated annual cost > 8 billion dollars. A newly validated CAP outcomes prediction rule developed by Fine and colleagues has been advocated as a guide to hospitalization decisions. OBJECTIVE: To evaluate the clinical characteristics, costs of care, and resource utilization of patients with low-risk CAP at an urban public hospital serving an indigent population. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study from June 1, 1994 to May 31, 1996. MAIN OUTCOME MEASURES: Clinical characteristics and costs of care of patients with low-risk CAP and features associated with low-risk CAP in this population. RESULTS: A total of 522 patients were identified at the time of hospital admission as having CAP; 97 patients (19%) were HIV positive on hospital admission and excluded. Of the remaining 425 patients, 253 patients (60%) were classified as pneumonia severity index (PSI) class I-III (low risk). Of the patients with low-risk CAP, only four patients (1.6%; 95% confidence interval, 0.4 to 4.0%) died during hospitalization. Low-risk CAP was both costly and accounted for significant resource use (35.4% of total CAP costs, and 45% of all CAP bed days). Of the patients with low-risk CAP, there were 138 patients (55%) who could potentially have been treated as outpatients (absence of altered mental status, hypotension, hypoxia on hospital admission, or direct ICU admission). However, 49% of these patients had a history of alcoholism, 20% had a blood alcohol level > 50 mg/dL, and 44% were homeless. CONCLUSIONS: A significant proportion of the patients admitted with CAP to a public hospital had low-risk CAP and accounted for a significant proportion of the CAP bed days and costs. The use of the PSI accurately predicted which patients would be at low risk for death; however, the utility of using the PSI to reduce low-risk CAP hospital admissions would have been of limited benefit. High rates of homelessness, substance abuse, and medical needs not captured in the PSI would preclude many of these patients from unsupervised outpatient treatment.

Adolescent↗

Practice variation in respiratory therapy documentation during mechanical ventilation.

STUDY OBJECTIVES: Implementation of new ventilatory strategies such as lung-protective ventilation for ARDS will require a multidisciplinary approach with considerable physician and respiratory therapy (RT) interaction. One of the key factors in this communication is complete and accurate RT documentation of ventilator settings. Few studies have explored the quality and variability of this documentation. DESIGN: Population-based cross-sectional study. SETTING: Seventeen adult hospitals in King County, WA. PARTICIPANTS/INTERVENTIONS: We compared the blank RT ICU flow sheet for each institution to the 1992 American Association for Respiratory Care (AARC) clinical practice guidelines (CPGs) for patient-ventilator system checks. We interviewed RT managers at each hospital about their practices. Finally, we reviewed selected charts of patients with acute lung injury (ALI) or ARDS from each hospital to evaluate the documentation. MEASUREMENTS/RESULTS: We found substantial variability in RT documentation practices and in their extent of compliance with the AARC CPGs. Only 15 of 52 items recommended by the AARC CPGs were included on blank RT flow sheets of every hospital in our study, and only 26 of 52 items were found on charts of ALI/ARDS patients at most hospitals (ie, > or =10 of 17 hospitals). Only 10 of 17 RT department managers reported using the AARC CPGs as a basis for their documentation policies. Items necessary for the implementation of lung-protective ventilation for ALI/ARDS patients were recorded inconsistently and were not included in the AARC CPGs. Plateau pressure was found on all reviewed charts of ALI/ARDS patients at only 10 of 17 hospitals. CONCLUSIONS: Considerable variability exists in RT documentation practices. We suggest that new guidelines be developed for documenting the care of patients receiving mechanical ventilation, in light of recent data on ventilator weaning and the management of ALI/ARDS, and that their effect on practice and outcomes be evaluated.

Cross-Sectional Studies↗

Detecting Stenotrophomonas maltophilia does not reduce survival of patients with cystic fibrosis.

Stenotrophomonas maltophilia is a gram-negative bacterium that has been cultured with increasing prevalence from the sputum of patients with cystic fibrosis (CF). We conducted a cohort study, using the Cystic Fibrosis Foundation Registry, to assess the effect of S. maltophilia on survival. We studied all patients in this registry from 1991 to 1997 who were older than 6 years of age, were S. maltophilia negative in the first year of enrollment, and had their CF diagnosed before the age of 45 years (n = 19,255 in the study). We compared patients who acquired S. maltophilia with those who did not, using survival analysis. A total of 1,673 (8.7%) had at least one sputum sample positive for S. maltophilia. Compared with patients without S. maltophilia, those patients positive for S. maltophilia had the following baseline characteristics before detection: lower FEV(1) % pred (p < 0.001); older (p = 0.001); more likely to be female (p = 0.003); and more pulmonary exacerbations (p < 0.001), outpatient visits (p < 0.002), and total hospitalizations (p < 0.001). After controlling for differences in severity of disease and coinfection with Pseudomonas aeruginosa, the hazard ratio associated with S. maltophilia detection was 0.89 (95% confidence interval, 0.75-1.05). Although patients with CF who acquire S. maltophilia have more advanced disease than those who do not acquire this organism, detection does not independently affect short-term survival (3 years).

Adolescent↗

Studying communication about end-of-life care during the ICU family conference: development of a framework.

PURPOSE: Family-clinician communication in the intensive care unit (ICU) about withholding and withdrawing life support occurs frequently, yet few data exist to guide clinicians in its conduct. The purpose of this study was to develop an understanding of the way this communication is currently conducted. METHODS: We identified family conferences in the ICUs of 4 Seattle-area hospitals. Conferences were eligible if the physician leading the conference believed that discussion about withholding or withdrawing life support or the delivery of bad news was likely to occur and if all conference participants consented to participate. Fifty conferences were audiotaped, transcribed, and analyzed by using the principles of grounded theory. RESULTS: We developed 2 frameworks for describing and understanding this communication. The first framework describes communication content, including introductions, information exchange, discussions of the future, and closings. The second framework describes communication styles and support provided to families and other clinicians and includes a variety of techniques such as active listening, acknowledging informational complexity and emotional difficulty of the situation, and supporting family decision making. These frameworks identify what physicians discuss, how they present and respond to issues, and how they support families during these conferences. CONCLUSIONS: This article describes a qualitative methodology to understand clinician-family communication during the ICU family conference concerning end-of-life care and provides a frame of reference that may help guide clinicians who conduct these conferences. We also identify strategies clinicians use to improve communication and enhance the support provided. Further analyses and studies are needed to identify whether this framework or these strategies can improve family understanding or satisfaction or improve the quality care in the ICU.

Adolescent↗