Lors du syndrome de detresse respiratoire de l'adulte, il y a stimulation de l'agregation plaquettaire ce qui libere des substances vasoconstrictives qui contribuent a l'hypertension pulmonaire et a la bronchoconstriction ce qui altere les relations ventilation-perfusion pulmonaires

The dichotomous classification of pleural fluid as a transudate or an exudate simplifies diagnostic efforts in determining the cause of pleural effusions. Multiple pleural fluid tests are available to discriminate between these two classes of effusions. Tests commonly used in clinical practice depend on the detection in pleural fluid of large-molecular-weight chemicals that enter the pleural space to greater degrees in conditions associated with exudative compared with transudative effusions. Considerable misclassifications can occur with all available testing strategies, so clinicians benefit from adopting a nondichotomous, bayesian approach for interpreting test results.

It is paradoxical that Hippocrates established in ancient times the clinical importance of pleural infections, yet only a few high-quality trials have studied this common condition during the inter...

Tracheostomy is the most common surgical procedure performed on critically ill patients. For those who survive their critical illnesses but remain ventilator-dependent, tracheostomy provides patients with a secure airway that frees the mouth for oral nutrition, enhances verbalized speech, and promotes generalized comfort. Avoiding complications from tracheostomy requires a skilled multi-disciplinary approach to ensure that the benefits outweigh the risks of the procedure.

Resident and subspecialty fellow trainees in the intensive care unit (ICU) present risks for patient safety because of their inexperience yet offer opportunities to promote safe patient care because of their around-the-clock presence and their involvement in frontline processes of care. Most trainees approach their ICU experiences without previous education in performance improvement or patient safety. This article reviews the barriers that are faced by residents in providing safe patient care and outlines the nature of a patient safety curriculum that could tap the opportunities that are presented by trainees to promote safer patient care.

Physicians, critical care nurses, and intensive care unit (ICU) residents have become intimately aware that medical errors and mishaps occur all too often in the course of their clinical practices. These errors may surface as obvious mistakes when catastrophic consequences occur, exemplified by the transfusion of mistyped red blood cells in patients with acute hemolytic reactions—or they may remain undetected if not actively anticipated and pursued, as occurs with improper timing of prophylactic surgical antibiotics in patients who experience a subtle increased risk of postoperative infections. Although there are many factors underlying these errors, the high complexity of critical care medicine is a major contributor to their occurrence.These complexities make medical errors in the ICU frequent and, to some degree, inevitable. However, complacency toward the inevitability of medical errors is no longer acceptable. The almost 100,000 preventable deaths due to medical errors cited by the Institute of Medicine far outstrips the annual deaths attributable to many leading cancers and from highway accidents. Increased public, governmental, payer, and regulatory awareness of the health burden from medical errors has driven the health care community to renew its Hippocratic oath of “First, do no harm” and initiate change.With regard to patient safety, critical care medicine represents a nexus of both great need and great promise. The need derives from the danger inherent in the ICU where severe illnesses produce unpredictable clinical instabilities that drive clinicians to act quickly and decisively, often in the absence of comprehensive diagnostic assessments. Physician fatigue and “input overload” further compound the potential for medical errors. The promise derives from the intensivist's valuing of data collection and analysis, information technology, teamwork, multidisciplinary cooperation, and performance improvement. It is no wonder that the critical care practitioners have assumed central leadership in advancing quality improvement and patient safety.This issue of the Critical Care Clinics profiles some of these leaders and examines the unique challenges to patient safety in the ICU and roadmaps for improving the safety of patient care. We anticipate that these papers, from a renowned group of experts in this field, will channel resources and stimulate discussion of the integration of quality management and systems engineering into critical care and state a clear need for more research in the area of patient safety in the ICU.In an introductory article, Dr. Pronovost and colleague sets the stage with his discussion of how to define and measure safety in health care. Dr. Hansen-Flaschen et al follow with a discussion of the use of failure mode and effects analysis, so effectively employed by other industries in error prevention. The next three articles written by Drs. Render and Hirschorn, Dr. Chang et al, and Drs. Bria and Shabot, respectively, provide us with a description of potential environmental, cultural, organizational, and technologic strategies designed to enhance clinical safety. Dr. Goldstein describes, frames and analyzes the relationship between the emergency department and the ICU and the potential barriers that interdepartmental care pose to the care of the critically ill.Dr. Hussain, Ms. Kao, and Drs. Shulman and Ost deal with the crucial issues of medication errors, transfusion errors, and infection control. Recognition of the importance of these topics has focused attention on the risks imposed by health care advances. Drs. Heffner and Zeno and Ms. Ellis discuss the impact of the educational process and training on patient safety and ways of reorganizing medical education around quality improvement. Dr. Marinelli examines the role of regulation on improvements in patient safety. Finally, Dr. Angus takes a wide-ranging and creative view of how organizational, cultural, and technologic advances will change the way critical care medicine is practiced in the future.The future is rife with opportunity to harness the promise offered by the ICU, new technology, and systems thinking to fulfill the ancient dictum “First, do no harm.” This issue is but a small step in moving this process forward. Physicians, critical care nurses, and intensive care unit (ICU) residents have become intimately aware that medical errors and mishaps occur all too often in the course of their clinical practices. These errors may surface as obvious mistakes when catastrophic consequences occur, exemplified by the transfusion of mistyped red blood cells in patients with acute hemolytic reactions—or they may remain undetected if not actively anticipated and pursued, as occurs with improper timing of prophylactic surgical antibiotics in patients who experience a subtle increased risk of postoperative infections. Although there are many factors underlying these errors, the high complexity of critical care medicine is a major contributor to their occurrence. These complexities make medical errors in the ICU frequent and, to some degree, inevitable. However, complacency toward the inevitability of medical errors is no longer acceptable. The almost 100,000 preventable deaths due to medical errors cited by the Institute of Medicine far outstrips the annual deaths attributable to many leading cancers and from highway accidents. Increased public, governmental, payer, and regulatory awareness of the health burden from medical errors has driven the health care community to renew its Hippocratic oath of “First, do no harm” and initiate change. With regard to patient safety, critical care medicine represents a nexus of both great need and great promise. The need derives from the danger inherent in the ICU where severe illnesses produce unpredictable clinical instabilities that drive clinicians to act quickly and decisively, often in the absence of comprehensive diagnostic assessments. Physician fatigue and “input overload” further compound the potential for medical errors. The promise derives from the intensivist's valuing of data collection and analysis, information technology, teamwork, multidisciplinary cooperation, and performance improvement. It is no wonder that the critical care practitioners have assumed central leadership in advancing quality improvement and patient safety. This issue of the Critical Care Clinics profiles some of these leaders and examines the unique challenges to patient safety in the ICU and roadmaps for improving the safety of patient care. We anticipate that these papers, from a renowned group of experts in this field, will channel resources and stimulate discussion of the integration of quality management and systems engineering into critical care and state a clear need for more research in the area of patient safety in the ICU. In an introductory article, Dr. Pronovost and colleague sets the stage with his discussion of how to define and measure safety in health care. Dr. Hansen-Flaschen et al follow with a discussion of the use of failure mode and effects analysis, so effectively employed by other industries in error prevention. The next three articles written by Drs. Render and Hirschorn, Dr. Chang et al, and Drs. Bria and Shabot, respectively, provide us with a description of potential environmental, cultural, organizational, and technologic strategies designed to enhance clinical safety. Dr. Goldstein describes, frames and analyzes the relationship between the emergency department and the ICU and the potential barriers that interdepartmental care pose to the care of the critically ill. Dr. Hussain, Ms. Kao, and Drs. Shulman and Ost deal with the crucial issues of medication errors, transfusion errors, and infection control. Recognition of the importance of these topics has focused attention on the risks imposed by health care advances. Drs. Heffner and Zeno and Ms. Ellis discuss the impact of the educational process and training on patient safety and ways of reorganizing medical education around quality improvement. Dr. Marinelli examines the role of regulation on improvements in patient safety. Finally, Dr. Angus takes a wide-ranging and creative view of how organizational, cultural, and technologic advances will change the way critical care medicine is practiced in the future. The future is rife with opportunity to harness the promise offered by the ICU, new technology, and systems thinking to fulfill the ancient dictum “First, do no harm.” This issue is but a small step in moving this process forward.

Background: Although clinical practice guidelines endorse the use of pleural fluid pH to select patients with parapneumonic effusions for pleural drainage, no studies have reported likelihood ratios for pleural fluid pH. Objectives: We derived and tested the value of continuous likelihood ratios for selecting pneumonia patients for pleural drainage. Methods: Patient level pleural fluid pH results were obtained from a registry of primary studies that assessed the discriminative properties of pH. Multilevel likelihood ratios were calculated for four pH intervals. Continuous likelihood ratios were derived from logistic regression using discrete pH values. Binary, multilevel and continuous likelihood ratios were compared to evaluate the statistical (χ2) and clinical advantages of continuous likelihood ratios. Results: Hundred and ninety-seven pleural fluid pH results were retrieved from published reports and categorized into four pH ordinal intervals. Multilevel likelihood ratios ranged from a low of 0.13 (95% CI, 0.04–0.41) for pH values >7.40 to a high of 15.80 (95% CI, 7.04–35.45) for pH values ≤7.00. Logistic regression derived the following equation for continuous likelihood ratios: exp[–7.168(measured pH – 7.207)]. Continuous likelihood ratios offered more diagnostic information both statistically (p < 0.005) and clinically compared with binary and multilevel likelihood ratios. Conclusions: Analysis of a patient registry allows the derivation of an exponential equation that calculates continuous likelihood ratios for discrete pleural fluid pH values. Continuous likelihood ratios provide more clinically and statistically significant information compared with binary and multilevel likelihood ratios for calculating posttest probabilities of the need to drain parapneumonic effusions.

PURPOSE OF REVIEW:This review reports recent information on the occurrence of pleural effusions in association with disorders that produce interstitial parenchymal lung disease.RECENT FINDINGS:The occurrence of effusions has been expanded to include systemic sclerosis, polymyositis-dermatomyositis, several drugs, and several miscellaneous causes of interstitial lung disease (ILD).SUMMARY:Pleural effusions occur in patients with various forms of interstitial lung disease. The effusions require a clinical evaluation to exclude complications of therapy and coexisting conditions unrelated to the underlying ILD.

Health care providers, hospital administrators, and politicians face competing challenges to reduce clinical errors, control expenditure, increase access and throughput, and improve quality of care. The safe management of the acutely ill inpatient presents particular difficulties. In the first of five Lancet articles on this topic we discuss patients' safety in the acute hospital. We also present a framework in which responsibility for improvement and better integration of care can be considered at the level of patient, local environment, hospital, and health care system; and the other four papers in the series will examine in greater detail methods for measuring, monitoring, and improving inpatient safety.

In evaluating pleural effusions, clinicians perform thoraceninstance, recommend measuring pleural fluid-to-serum albumin gradients when patients with congestive heart failure have tesis and pleural fluid analysis most often by Light’s criteria to establish the exudative or transudative nature of the effuan exudative effusion by Light’s criteria (7). A Bayesian approach addresses these limitations of binary sion (1). Light’s criteria (2) dichotomize effusions into exudative or transudative categories with the use of three pleural testing strategies (10). Rather than diagnosing the presence or absence of a condition, a Bayesian strategy uses test results test criteria: pleural fluid-to-serum protein ratio, pleural fluid lactate dehydrogenase (LDH) concentration, and pleural fluidto generate likelihood ratios that increase or decrease a clinician’s pretest estimate of the probability of disease. Likelito-serum LDH ratio. Several other pleural fluid test criteria have similar diagnostic accuracies as compared with each of hood ratios represent the likelihood that a positive test result would be found in a patient with as opposed to without the individual tests within Light’s criteria (3). These criteria include pleural fluid cholesterol, pleural fluid-to-serum cholesdisease (10). Likelihood ratios are usually calculated using a single test result cutoff point. These binary likelihood ratios terol ratio, pleural fluid protein, and pleural fluid-to-serum have values above 1 for test results that increase the likelialbumin gradient. All of these tests dichotomize effusions into hood of an exudative effusion and values below 1 that deexudative or transudative categories by determining whether crease the likelihood. We previously published multilevel the test results are above or below a single cutoff point. likelihood ratios for pleural fluid test criteria commonly used Problems exist, however, with these pleural fluid test criteria to diagnose exudative pleural effusions (11). Multilevel likelias commonly used in clinical practice. First, dichotomizing hood ratios are calculated by using two or more cutoff points effusions into exudates and transudates by using a single for the range of possible test results. These multiple cutoff cutoff point loses much of the information contained in pleupoints demarcate test result intervals that are each associated ral fluid tests, which generate continuous numeric results (4). with a different likelihood that the patient has an exudative Test results just beyond and those extremely beyond a cutoff effusion. Although breaking up continuous test result values point are treated the same in that both establish the presence into ordinal intervals with multiple cutoff points improves of an exudative effusion. This binary diagnostic strategy exdiagnostic precision as compared with using a single cutoff plains why Light’s criteria frequently misclassify as exudates point, they only provide an average value for the range of the pleural effusions associated with congestive heart failure likelihood ratios that exist within each of the test result inter(5–7), which usually have borderline pleural fluid test results vals (4). A more precise diagnostic approach would calculate when in the exudative range. It also contributes to the misclassian exact likelihood ratio for each possible discrete pleural fluid fication that occurs in 1 to 10% of patients with malignant test result. Such discrete likelihood ratios are called continuous pleural effusions who appear to have transudative effusions likelihood ratios (12). Methods for calculating continuous likeby Light’s criteria (8). Second, combining two or more tests lihood ratios have been reported for very few conditions. using a single cutoff point for each test, as done by Light’s In this study, we analyze with logistic regression a multicencriteria, increases sensitivity but decreases specificity because ter registry of pleural fluid test values from patients with estabonly one of the tests needs to be positive to define an exudative lished diagnoses to derive equations that calculate continuous effusion (9). Finally, the lower specificity caused by combining likelihood ratios for pleural fluid test criteria for exudative several criteria encourages physicians to commonly order addieffusions. We also compare continuous likelihood ratios with tional—and usually unnecessary—pleural fluid tests when inimultilevel and binary likelihood ratios to determine whether tial test results do not fit clinical circumstances. Experts, for continuous likelihood ratios provide statistically significant and clinically important advantages.

BACKGROUNDThere is no consensus on the effectiveness of inhaled corticosteroids for the treatment of chronic obstructive pulmonary disease (COPD).PURPOSETo evaluate the long-term effects of inhaled corticosteroids on the rate of FEV1 decline in patients with COPD.DATA SOURCESMEDLINE, EMBASE, CISCOM, and AMED databases and the Cochrane Library (1966 to December 2002), reference lists from identified articles, and consultation with experts. Searches were not limited to the English language.STUDY SELECTIONRandomized, placebo-controlled trials that examined the rate of FEV1 decline as a primary outcome in patients with COPD.DATA EXTRACTIONTwo reviewers independently extracted the data by using predetermined criteria.DATA SYNTHESISFor the six studies that met the inclusion criteria, the summary estimate for the difference in FEV1 decline between the placebo and treatment groups was -5.0 +/- 3.2 mL/y (95% CI, -11.2 to 1.2 mL/y; P = 0.11).CONCLUSIONSThe use of inhaled corticosteroids was not associated with the rate of FEV1 decline in 3571 patients followed for 24 to 54 months.

STUDY OBJECTIVE:Expert consensus recommends testing pleural fluid for pH to assist the selection of patients with malignant pleural effusions for pleurodesis. Although published studies report an association between pleural fluid pH and patient outcomes after pleurodesis, clinicians have no definitive information on how to use pH to select patients for pleurodesis. Thus, we quantitatively assessed different methods for deriving likelihood ratios from pleural fluid pH and evaluated the potential role of pH in selecting patients for pleurodesis.DATA SOURCES:MEDLINE, systematic reviews, article reference lists, and contact with primary authors.STUDY SELECTION:Studies that assessed the impact of pleural fluid pH on survival and pleurodesis failure rates among patients with malignant pleural effusions.DATA EXTRACTION:Primary authors provided their data in electronic spreadsheets.DATA SYNTHESIS:Retrieved data sets included survival and pleurodesis failure rates for 417 patients and 433 patients, respectively. Binary, multilevel, and continuous likelihood ratios were calculated to estimate the likelihood of death within 3 months of pleurodesis or pleurodesis failure rates. Values for the likelihood ratios were compared for each of the three strategies, and relative clinical and statistical significance were assessed. Pleural fluid pH had marginal performance for identifying patients with < 3-month anticipated survival; binary likelihood ratios provided as much information as the multilevel and continuous strategies. Likelihood ratios for identifying patients likely to fail pleurodesis were clinically useful. Continuous likelihood ratios provided statistically more information as compared with the multilevel and binary strategies.CONCLUSIONS:Pleural fluid pH has marginal value for estimating death within 3 months of pleurodesis, and binary likelihood ratios (cut point </= 7.20) perform as well as the other strategies assessed. Pleural fluid pH provides more useful information for estimating the likelihood of pleurodesis failure for which continuous likelihood ratios provide the most information as compared with binary or multilevel likelihood ratios.

BackgroundPleurodesis is important in the management of malignant pleural effusions, but no consensus exists on the optimal agent or methods of pleurodesis. How pleurodesis is practiced worldwide has not been studied.ObjectivesTo identify variations in the clinical practice of pleurodesis in major English-speaking countries, and to quantify the experience of pulmonologists on the effectiveness and adverse effects of different pleurodesis agents worldwide.MethodsEight hundred fifty-nine pulmonologists practicing in the United States, United Kingdom, Canada, Australia, and New Zealand participated in a Web-based survey.ResultsThe respondents collectively perform > 8,300 pleurodesis annually. Talc was the preferred agent by most respondents (slurry, 56%; poudrage, 12%), followed by tetracycline derivatives (26%), and bleomycin (7%). Differences were seen in pleurodesis practice patterns among practitioners among and within the surveyed countries. Physicians' overall satisfaction with the available pleurodesis agents was modest (5.0 out of 8), and the reported success rate averaged only 66%. Talc (both poudrage and slurry) was perceived as significantly more effective, but was associated with significantly more pain, nausea, and fever (p < 0.05). Respiratory failure occurred more commonly with talc poudrage than with other agents (p < 0.05), and had been observed by 70% and 54% of physicians who used talc poudrage and slurry, respectively.ConclusionsSignificant variations exist in how pleurodesis is performed worldwide. Pleurodesis agents currently available are perceived as suboptimal. Talc poudrage and slurry were perceived to be more effective, but were associated with more complications, including respiratory failure.

Tracheotomy provides airway access for critically ill patients who require prolonged mechanical ventilation. Performed by skilled operators, tracheotomy by open surgical and percutaneous techniques has a low risk of perioperative and long-term complications. No specific duration of translaryngeal intubation creates an absolute indication for tracheotomy. Timing of tracheotomy is based on the clinician's estimate that an individual patient will receive sufficient benefit by converting from translaryngeal intubation to a tracheostomy to warrant the procedure. A clear understanding of the benefits of tracheotomy along with attendant risks assists decision-making.

Tracheotomy is commonly performed in ventilator-dependent patients. Disadvantages to the procedure are perioperative complications, long-term airway injury, and the cost of the procedure. Benefits ascribed to tracheotomy vs prolonged translaryngeal intubation include improved patient comfort, more effective airway suctioning, decreased airway resistance, enhanced patient mobility, increased potential for speech, ability to eat orally, a more secure airway, accelerated ventilator weaning, reduced ventilator-associated pneumonia, and the ability to transfer ventilator-dependent patients from the ICU. None of these benefits, however, have been demonstrated in large-scale, prospective, randomized studies. It is proposed that there should be an anticipatory approach wherein tracheotomy is considered after an initial period of stabilization with the patient receiving mechanical ventilation when it becomes apparent that the patient will require prolonged ventilator assistance. Tracheotomy then is performed when the patient appears likely to gain one or more of the benefits ascribed to the procedure.

Increasing public awareness of the need to improve quality in health care and to limit unexplained variations in clinical practice have promoted interest in altering physician behavior. Unfortunately, many programs for changing the practice patterns of providers have proven less effective than anticipated. Interventions have often been initiated without a clear understanding of their theoretical basis or the empiric data supporting their use. This article reviews the various interventions available for altering physician behavior and their evidence of effectiveness.

Successful management of patients who require long-term ventilatory support requires a skilled approach to airway care. Tracheostomy provides multiple benefits to patient care in addition to provision of airway access for mechanical ventilation. Realization of these benefits, however, depends on knowledge of approaches for promoting speech and nutrition in the intubated patient, providing expert respiratory care, and initiating effective weaning and airway decannulation efforts.

STUDY OBJECTIVES The study assessed the interests of ambulatory cardiac patients in advance planning and their willingness to participate in rehabilitation program-based end-of-life education. DESIGN Observational survey study. SETTING Fourteen outpatient cardiac rehabilitation programs in 11 states. PARTICIPANTS Four hundred fifteen subjects enrolled in cardiac rehabilitation. MEASUREMENTS AND RESULTS A questionnaire determined patient preferences for advance planning, completion of advance directives, completion of patient-physician discussions on end-of-life care, and effects of health status on patient acceptance of life-sustaining interventions. Seventy-two percent of patients wanted to direct their own end-of-life care, 86% desired more information on advance directives, 62% wanted to learn about life-sustaining care, and 96% were receptive to advance-planning discussions with their physicians. Seventy-two percent of patients had considered that they might require life-sustaining care in the future; acceptability of resuscitative care depended on health status and probability of survival. However, only 15% had discussed advance planning with their physicians, and 10% were confident that their physicians understood their end-of-life wishes. Physicians and cardiovascular rehabilitation programs were considered desirable sources of information on advance planning. CONCLUSIONS Cardiac patients enrolled in rehabilitation programs want to learn more about end-of-life care and need more opportunities to discuss advance planning with their physicians. Patients consider cardiovascular rehabilitation programs to be acceptable sites for advance planning education.