How the National Heart, Lung, and Blood Institute (NHLBI) develops research priorities and supports critical care research.

This report provides a brief overview of some relevant ongoing research on critical care and how research priorities are determined by the National Heart, Lung, and Blood Institute. Long-term and patient-centered outcomes have become more prominent research questions for clinical studies in patients who are critically ill. Rehabilitation research would be appropriate in this context, and funding is most likely received through investigator-initiated R01 applications. National Institutes of Health program staff are available for discussion and advice and encourage contact from extramural investigators.

Improving long-term outcomes after discharge from intensive care unit: report from a stakeholders' conference.

BACKGROUND: Millions of patients are discharged from intensive care units annually. These intensive care survivors and their families frequently report a wide range of impairments in their health status which may last for months and years after hospital discharge. OBJECTIVES: To report on a 2-day Society of Critical Care Medicine conference aimed at improving the long-term outcomes after critical illness for patients and their families. PARTICIPANTS: Thirty-one invited stakeholders participated in the conference. Stakeholders represented key professional organizations and groups, predominantly from North America, which are involved in the care of intensive care survivors after hospital discharge. DESIGN: Invited experts and Society of Critical Care Medicine members presented a summary of existing data regarding the potential long-term physical, cognitive and mental health problems after intensive care and the results from studies of postintensive care unit interventions to address these problems. Stakeholders provided reactions, perspectives, concerns and strategies aimed at improving care and mitigating these long-term health problems. MEASUREMENTS AND MAIN RESULTS: Three major themes emerged from the conference regarding: (1) raising awareness and education, (2) understanding and addressing barriers to practice, and (3) identifying research gaps and resources. Postintensive care syndrome was agreed upon as the recommended term to describe new or worsening problems in physical, cognitive, or mental health status arising after a critical illness and persisting beyond acute care hospitalization. The term could be applied to either a survivor or family member. CONCLUSIONS: Improving care for intensive care survivors and their families requires collaboration between practitioners and researchers in both the inpatient and outpatient settings. Strategies were developed to address the major themes arising from the conference to improve outcomes for survivors and families.

Beyond mortality: future clinical research in acute lung injury.

Mortality in National Heart, Lung and Blood Institute-sponsored clinical trials of treatments for acute lung injury (ALI) has decreased dramatically during the past two decades. As a consequence, design of such trials based on a mortality outcome requires ever-increasing numbers of patients. Recognizing that advances in clinical trial design might be applicable to these trials and might allow trials with fewer patients, the National Heart, Lung and Blood Institute convened a workshop of extramural experts from several disciplines. The workshop assessed the current state of clinical research addressing ALI, identified research needs, and recommended: (1) continued performance of trials evaluating treatments of patients with ALI; (2) development of strategies to perform ALI prevention trials; (3) observational studies of patients without ALI undergoing prolonged mechanical ventilation; and (4) development of a standardized format for reporting methods, endpoints, and results of ALI trials.

Pulmonary-artery versus central venous catheter to guide treatment of acute lung injury.

BACKGROUND: The balance between the benefits and the risks of pulmonary-artery catheters (PACs) has not been established. METHODS: We evaluated the relationship of benefits and risks of PACs in 1000 patients with established acute lung injury in a randomized trial comparing hemodynamic management guided by a PAC with hemodynamic management guided by a central venous catheter (CVC) using an explicit management protocol. Mortality during the first 60 days before discharge home was the primary outcome. RESULTS: The groups had similar baseline characteristics. The rates of death during the first 60 days before discharge home were similar in the PAC and CVC groups (27.4 percent and 26.3 percent, respectively; P=0.69; absolute difference, 1.1 percent; 95 percent confidence interval, -4.4 to 6.6 percent), as were the mean (+/-SE) numbers of both ventilator-free days (13.2+/-0.5 and 13.5+/-0.5; P=0.58) and days not spent in the intensive care unit (12.0+/-0.4 and 12.5+/-0.5; P=0.40) to day 28. PAC-guided therapy did not improve these measures for patients in shock at the time of enrollment. There were no significant differences between groups in lung or kidney function, rates of hypotension, ventilator settings, or use of dialysis or vasopressors. Approximately 90 percent of protocol instructions were followed in both groups, with a 1 percent rate of crossover from CVC- to PAC-guided therapy. Fluid balance was similar in the two groups, as was the proportion of instructions given for fluid and diuretics. Dobutamine use was uncommon. The PAC group had approximately twice as many catheter-related complications (predominantly arrhythmias). CONCLUSIONS: PAC-guided therapy did not improve survival or organ function but was associated with more complications than CVC-guided therapy. These results, when considered with those of previous studies, suggest that the PAC should not be routinely used for the management of acute lung injury. (ClinicalTrials.gov number, NCT00281268.).

Comparison of two fluid-management strategies in acute lung injury.

BACKGROUND: Optimal fluid management in patients with acute lung injury is unknown. Diuresis or fluid restriction may improve lung function but could jeopardize extrapulmonary-organ perfusion. METHODS: In a randomized study, we compared a conservative and a liberal strategy of fluid management using explicit protocols applied for seven days in 1000 patients with acute lung injury. The primary end point was death at 60 days. Secondary end points included the number of ventilator-free days and organ-failure-free days and measures of lung physiology. RESULTS: The rate of death at 60 days was 25.5 percent in the conservative-strategy group and 28.4 percent in the liberal-strategy group (P=0.30; 95 percent confidence interval for the difference, -2.6 to 8.4 percent). The mean (+/-SE) cumulative fluid balance during the first seven days was -136+/-491 ml in the conservative-strategy group and 6992+/-502 ml in the liberal-strategy group (P<0.001). As compared with the liberal strategy, the conservative strategy improved the oxygenation index ([mean airway pressure x the ratio of the fraction of inspired oxygen to the partial pressure of arterial oxygen]x100) and the lung injury score and increased the number of ventilator-free days (14.6+/-0.5 vs. 12.1+/-0.5, P<0.001) and days not spent in the intensive care unit (13.4+/-0.4 vs. 11.2+/-0.4, P<0.001) during the first 28 days but did not increase the incidence or prevalence of shock during the study or the use of dialysis during the first 60 days (10 percent vs. 14 percent, P=0.06). CONCLUSIONS: Although there was no significant difference in the primary outcome of 60-day mortality, the conservative strategy of fluid management improved lung function and shortened the duration of mechanical ventilation and intensive care without increasing nonpulmonary-organ failures. These results support the use of a conservative strategy of fluid management in patients with acute lung injury. (ClinicalTrials.gov number, NCT00281268 [ClinicalTrials.gov].).

Recommendations for informed consent forms for critical care clinical trials.

BACKGROUND: Many subjects enrolled in research studies have a limited understanding of the research to which they consented. OBJECTIVE: To develop recommendations to enhance comprehensiveness and understanding of informed consent forms used in critical care clinical trials. DESIGN: Consensus process. RECOMMENDATIONS: We provide recommendations regarding the U.S. federally required basic and additional elements of informed consent as applied to critical care clinical trials. We also identify issues that investigators need to address, if relevant, in the informed consent forms of critical care clinical trials. These include the description, in understandable language, of complex and detailed experimental protocols that are the focus of the clinical trial, disclosure of death as a risk factor if mortality is an outcome variable, and the identification of who can legally serve as the prospective subject's surrogate. We also offer suggestions to enhance subjects' understanding of informed consent forms. CONCLUSIONS: The literature on informed consent forms suggest that shorter informed consent forms written at a lower reading level, when read carefully, might provide better subject understanding. Prospective evaluation is needed to determine whether our recommendations enhance the informed consent process.

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.

Future research directions in acute lung injury: summary of a National Heart, Lung, and Blood Institute working group.

Acute lung injury (ALI) and its more severe form, the acute respiratory distress syndrome (ARDS), are syndromes of acute respiratory failure that result from acute pulmonary edema and inflammation. The development of ALI/ARDS is associated with several clinical disorders including direct pulmonary injury from pneumonia and aspiration as well as indirect pulmonary injury from trauma, sepsis, and other disorders such as acute pancreatitis and drug overdose. Although mortality from ALI/ARDS has decreased in the last decade, it remains high. Despite two major advances in treatment, low VT ventilation for ALI/ARDS and activated protein C for severe sepsis (the leading cause of ALI/ARDS), additional research is needed to develop specific treatments and improve understanding of the pathogenesis of these syndromes. The NHLBI convened a working group to develop specific recommendations for future ALI/ARDS research. Improved understanding of disease heterogeneity through use of evolving biologic, genomic, and genetic approaches should provide major new insights into pathogenesis of ALI. Cellular and molecular methods combined with animal and clinical studies should lead to further progress in the detection and treatment of this complex disease.