Steven Y. Chang

Early Identification of Patients at Risk of Acute Lung Injury: Evaluation of Lung Injury Prediction Score in a Multicenter Cohort Study

RATIONALE Accurate, early identification of patients at risk for developing acute lung injury (ALI) provides the opportunity to test and implement secondary prevention strategies. OBJECTIVES To determine the frequency and outcome of ALI development in patients at risk and validate a lung injury prediction score (LIPS). METHODS In this prospective multicenter observational cohort study, predisposing conditions and risk modifiers predictive of ALI development were identified from routine clinical data available during initial evaluation. The discrimination of the model was assessed with area under receiver operating curve (AUC). The risk of death from ALI was determined after adjustment for severity of illness and predisposing conditions. MEASUREMENTS AND MAIN RESULTS Twenty-two hospitals enrolled 5,584 patients at risk. ALI developed a median of 2 (interquartile range 1-4) days after initial evaluation in 377 (6.8%; 148 ALI-only, 229 adult respiratory distress syndrome) patients. The frequency of ALI varied according to predisposing conditions (from 3% in pancreatitis to 26% after smoke inhalation). LIPS discriminated patients who developed ALI from those who did not with an AUC of 0.80 (95% confidence interval, 0.78-0.82). When adjusted for severity of illness and predisposing conditions, development of ALI increased the risk of in-hospital death (odds ratio, 4.1; 95% confidence interval, 2.9-5.7). CONCLUSIONS ALI occurrence varies according to predisposing conditions and carries an independently poor prognosis. Using routinely available clinical data, LIPS identifies patients at high risk for ALI early in the course of their illness. This model will alert clinicians about the risk of ALI and facilitate testing and implementation of ALI prevention strategies. Clinical trial registered with www.clinicaltrials.gov (NCT00889772).

Structure, process, and annual ICU mortality across 69 centers: United States critical illness and injury trials group critical illness outcomes study

Objective:Hospital-level variations in structure and process may affect clinical outcomes in ICUs. We sought to characterize the organizational structure, processes of care, use of protocols, and standardized outcomes in a large sample of U.S. ICUs. Design:We surveyed 69 ICUs about organization, size, volume, staffing, processes of care, use of protocols, and annual ICU mortality. Setting:ICUs participating in the United States Critical Illness and Injury Trials Group Critical Illness Outcomes Study. Subjects:Sixty-nine intensivists completed the survey. Measurements and Main Results:We characterized structure and process variables across ICUs, investigated relationships between these variables and annual ICU mortality, and adjusted for illness severity using Acute Physiology and Chronic Health Evaluation II. Ninety-four ICU directors were invited to participate in the study and 69 ICUs (73%) were enrolled, of which 25 (36%) were medical, 24 (35%) were surgical, and 20 (29%) were of mixed type, and 64 (93%) were located in teaching hospitals with a median number of five trainees per ICU. Average annual ICU mortality was 10.8%, average Acute Physiology and Chronic Health Evaluation II score was 19.3, 58% were closed units, and 41% had a 24-hour in-house intensivist. In multivariable linear regression adjusted for Acute Physiology and Chronic Health Evaluation II and multiple ICU structure and process factors, annual ICU mortality was lower in surgical ICUs than in medical ICUs (5.6% lower [95% CI, 2.4–8.8%]) or mixed ICUs (4.5% lower [95% CI, 0.4–8.7%]). We also found a lower annual ICU mortality among ICUs that had a daily plan of care review (5.8% lower [95% CI, 1.6–10.0%]) and a lower bed-to-nurse ratio (1.8% lower when the ratio decreased from 2:1 to 1.5:1 [95% CI, 0.25–3.4%]). In contrast, 24-hour intensivist coverage (p = 0.89) and closed ICU status (p = 0.16) were not associated with a lower annual ICU mortality. Conclusions:In a sample of 69 ICUs, a daily plan of care review and a lower bed-to-nurse ratio were both associated with a lower annual ICU mortality. In contrast to 24-hour intensivist staffing, improvement in team communication is a low-cost, process-targeted intervention strategy that may improve clinical outcomes in ICU patients.

Protocols in the management of critical illness

Care of the critically ill patient is becoming increasingly complex. Protocols, which standardize care of patients with similar diseases, represent a potential solution to managing multiple simultaneous problems in critically ill patients. In this article, we examine the advantages and disadvantages to care protocolization, and posit that careful and thoughtful implementation of protocols is likely to benefit patients. We also discuss the potential for unintended consequences, and even harm, with protocolization in critically ill patients using the Critical Illness Outcomes Study as a model to examine the effects of protocolization in large populations of intensive care patients.

Contemporary Ventilator Management in Patients With and at Risk of ALI/ARDS

BACKGROUND: Ventilator practices in patients at risk for acute lung injury (ALI) and ARDS are unclear. We examined factors associated with choice of set tidal volumes (VT), and whether VT < 8 mL/kg predicted body weight (PBW) relates to the development of ALI/ARDS. METHODS: We performed a secondary analysis of a multicenter cohort of adult subjects at risk of lung injury with and without ALI/ARDS at onset of invasive ventilation. Descriptive statistics were used to describe ventilator practices in specific settings and ALI/ARDS risk groups. Logistic regression analysis was used to determine the factors associated with the use of VT < 8 mL/kg PBW and the relationship of VT to ALI/ARDS development and outcome. RESULTS: Of 829 mechanically ventilated patients, 107 met the criteria for ALI/ARDS at time of intubation, and 161 developed ALI/ARDS after intubation (post-intubation ALI/ARDS). There was significant intercenter variability in initial ventilator settings, and in the incidence of ALI/ARDS and post-intubation ALI/ARDS. The median VT was 7.96 (IQR 7.14–8.94) mL/kg PBW in ALI/ARDS subjects, and 8.45 (IQR 7.50–9.55) mL/kg PBW in subjects without ALI/ARDS (P = .004). VT decreased from 8.40 (IQR 7.38–9.37) mL/kg PBW to 7.97 (IQR 6.90–9.23) mL/kg PBW (P < .001) in those developing post-intubation ALI/ARDS. Among subjects without ALI/ARDS, VT ≥ 8 mL/kg PBW was associated with shorter height and higher body mass index, while subjects with pneumonia were less likely to get ≥ 8 mL/kg PBW. Initial VT ≥ 8 mL/kg PBW was not associated with the post-intubation ALI/ARDS (adjusted odds ratio 1.30, 95% CI 0.74–2.29) or worse outcomes. Post-intubation ALI/ARDS subjects had mortality similar to subjects intubated with ALI/ARDS. CONCLUSIONS: Clinicians seem to respond to ALI/ARDS with lower initial VT. Initial VT, however, was not associated with the development of post-intubation ALI/ARDS or other outcomes. (ClinicalTrials.gov registration NCT00889772)

Regional ICU care: the future is now.

Critical care is an important consideration in the current health care debate and with good reason. Many citizens question the enormous expenditures incurred in the intensive care unit (ICU), along with the rationale for prolonged and expensive treatment for patients for whom survival is a remote possibility. An estimated 1% of our entire gross domestic product (GDP) is spent in our ICUs, and about 40% of Medicare dollars are spent on the last year of a patient’s life. The ICU also is where we care for a higher proportion of older patients as well as underor noninsured patients. Consequently, debates about ‘‘death panels’’ and end-of-life care are often centered in ICUs, where stark choices are presented to dying patients, their families, and medical staff. Many of us who work in critical care often feel that we are delivering costly care to patients who are unlikely to recover. This is an inevitable dilemma but perhaps not an unsolvable one. For more than a decade, the concept of ‘‘regionalization’’ has been proposed as a way to make ICUs more efficient and more cost-effective. Although some variant of critical care is available in almost every part of the country, accessibility, quality, and resources are far from evenly distributed. Most people prefer the convenience of receiving care locally—from physicians they are familiar with and have confidence in. Changes in the delivery of critical care services have been made at a relatively rapid pace such that only the most experienced of centers are able to effectively care for the most critically ill patients. Given this, consideration should be given to regionalizing most critical care services such as practiced in trauma and pediatric critical care. The Regional ICU concept posits that, since resources and personnel are more concentrated in more densely populated areas, we should concurrently concentrate them in larger facilities, which may be less convenient but are also almost certainly better equipped to handle the most complex medical problems. Such regional ICUs would: