Has mortality from acute respiratory distress syndrome decreased over time?: A systematic review.

RATIONALE: It is commonly stated that mortality from acute respiratory distress syndrome (ARDS) and acute lung injury (ALI) is decreasing. OBJECTIVES: To systematically review the literature assessing ARDS mortality over time and to determine patient- and study-level factors independently associated with mortality. METHODS: We searched multiple databases (MEDLINE, EMBASE, CINAHL, Cochrane CENTRAL) for prospective observational studies or randomized controlled trials (RCTs) published during the period 1984 to 2006 that enrolled 50 or more patients with ALI/ARDS and reported mortality. We pooled mortality estimates using random-effects meta-analysis and examined mortality trends before and after 1994 (when a consensus definition of ALI/ARDS was published) and factors associated with mortality using meta-regression models. MEASUREMENTS AND MAIN RESULTS: Of 4,966 studies, 89 met inclusion criteria (53 observational, 36 RCTs). There was a total of 18,900 patients (mean age 51.6 years; 39% female). Overall pooled weighted mortality was 44.3% (95% confidence interval [CI], 41.8-46.9). Mortality decreased with time in observational studies conducted before 1994; no temporal associations with mortality were demonstrated in RCTs (any time) or observational studies (after 1994). Pooled mortality from 1994 to 2006 was 44.0% (95% CI, 40.1-47.5) for observational studies, and 36.2% (95% CI, 32.1-40.5) for RCTs. Meta-regression identified study type (observational versus RCT, odds ratio, 1.36; 95% CI, 1.08-1.73) and patient age (odds ratio per additional 10 yr, 1.27; 95% CI, 1.07-1.50) as the only factors associated with mortality. CONCLUSIONS: A decrease in ARDS mortality was only seen in observational studies from 1984 to 1993. Mortality did not decrease between 1994 (when a consensus definition was published) and 2006, and is lower in RCTs than observational studies.

Pneumonia severity index class v patients with community-acquired pneumonia: characteristics, outcomes, and value of severity scores.

BACKGROUND: Community-acquired pneumonia (CAP) with a pneumonia severity index (PSI) score in risk class V (PSI-V) is a potentially life-threatening condition, yet the majority of patients are not admitted to the ICU. The aim of this study was to characterize CAP patients in PSI-V to determine the risk factors for ICU admission and mortality, and to assess the performance of CAP severity scores in this population. METHODS: Prospective observational study including hospitalized adults with CAP in PSI-V from 1996 to 2003. Clinical and laboratory data, microbiological findings, and outcomes were recorded. The PSI score; modified American Thoracic Society (ATS) score; the confusion, urea, respiratory rate, low BP (CURB) score, and CURB plus age of >/= 65 years score were calculated. A reduced score based on the acute illness variables contained in the PSI was also obtained. RESULTS: A total of 457 patients were included in the study (mean [+/- SD] age, 79 +/- 11 years), of whom 92 (20%) were admitted to the ICU. Patients in the ward were older (mean age, 82 +/- 10 vs 70 +/- 10 years, respectively) and had more comorbidities. ICU patients experienced significantly more acute organ failures. The mortality rate was higher in ICU patients, but also was high for non-ICU patients (37% vs 20%, respectively; p = 0,003). A low level of consciousness (odds ratio [OR], 3.95; 95% confidence interval [CI], 2 to 5) and shock (OR, 24.7; 95% CI, 14 to 44) were associated with a higher risk of death. The modified ATS severity rule had the best accuracy in predicting ICU admission and mortality. CONCLUSIONS: Most CAP patients PSI-V were treated on a hospital ward. Those admitted to the ICU were younger and had findings of more acute illness. The PSI performed well as a mortality prediction tool but was less appropriate for guiding site-of-care decisions.

Respiratory microbiology patterns within the first 24 h of ARDS diagnosis: influence on outcome.

BACKGROUND: Airway colonization and infection are frequent complications during the course of ARDS. The impact on outcomes of microbiological patterns recovered within the first 24 h after diagnosis has not been evaluated. OBJECTIVES: To describe the incidence and patterns of bronchial colonization and lung infection within the first 24 h of ARDS diagnosis and to evaluate the influence on ICU outcomes. METHODS: Prospective study of ARDS patients evaluated within 24 h of diagnosis. Patients were studied with tracheobronchial aspirate and right and left bronchoscopic protected specimen brush. All samples were cultured quantitatively. RESULTS: Fifty-five consecutive patients were included. Twelve patients (22%) were clinically suspected of having nosocomial pneumonia (NP), which was confirmed microbiologically in 7 patients, a frequency of 13%. In those patients without suspected pneumonia, we also found potentially pathogenic microorganisms (PPMs) and potentially drug-resistant microorganisms (PDRMs) in 36% and 31%, respectively. Mortality was not significantly higher in those patients with recovery of a PPM (87% vs 73%, p = 0.31), PDRM (89% vs 74%, p = 0.18), or with NP (79% vs 85%, p = 1.0). CONCLUSION: There is a strikingly high rate of PPM recovery in early ARDS. However, neither isolation of pathogenic microorganisms nor the confirmation of NP could be associated with an increased mortality.

Disposition of instilled versus nebulized tobramycin and imipenem in ventilated intensive care unit (ICU) patients.

BACKGROUND: Delivery of antibiotics to the lower respiratory tract could potentially achieve antimicrobial bronchial drug concentrations without toxicity. AIM: To assess bronchial and serum concentrations of imipenem or tobramycin obtained by nebulization or instillation in critically ill mechanically ventilated patients. METHODS: Prospective randomized open trial. Eighteen patients ventilated for more than 48 h were included. Two doses of imipenem/cilastatin (1000/500 mg) separated by 8 h, or two doses of tobramycin 200 mg separated by 12 h were randomly nebulized or instilled into the tracheal tube. Five bronchoaspirates (two bronchoscopic, three blind) and five blood samples were collected on a timed schedule after the second dose. Respiratory and serum samples were analysed by HPLC, and a subset of blood samples was also evaluated by enzyme-immunoassay. RESULTS: When instilled, imipenem/cilastatin obtained higher concentrations in respiratory secretions than when nebulized (P=0.022, 1 h after the last dose; P=0.029, 2 h after the last dose). Tobramycin showed equally high concentrations when nebulized or instilled. Instillation of tobramycin may result in significant accumulation in patients with renal failure. CONCLUSIONS: High bronchial concentrations of imipenem could only be achieved by instillation, whereas tobramycin seems suitable for both modes of administration. Instillation of these antibiotics is a safe procedure that achieves high drug concentrations in respiratory secretions.

[Results of a preventive program and assisted hospital discharge for COPD exacerbation. A feasibility study]. / Resultados de dos programas con intervención domiciliaria dirigidos a pacientes con enfermedad pulmonar obstructiva crónica evolucionada.

BACKGROUND AND OBJECTIVE: Exacerbation of chronic obstructive pulmonary disease (COPD) is one of the most frequent causes of hospital admission. We examined the results and feasibility of two programs conducted by a hospital respiratory unit aimed to reduce both the length of hospital stay and the number of hospital admissions for COPD acute exacerbation. PATIENTS AND METHOD: a) Assisted hospital discharge program: Patients admitted for acute exacerbation who met our criteria for early discharge were sent home with the support of a respiratory nurse. Home visits were carried out and direct phone contact with the nurse and physician was provided during a limited period of 6 weeks. Outcome variables studied were length of hospital admission and need for hospital reentry. b) Exacerbation prevention program: A group of patients with severe COPD and at least 3 hospital admissions for exacerbation during the previous year were included. These patients underwent an educational program and were given unlimited direct phone access to the respiratory nurse and physician. When necessary, home visits were carried out. The main outcome variable of this program was the number of hospital admissions. RESULTS: a) Assisted hospital discharge program: A total of 97 patients were included. The mean length of hospital stay was 5.4 1.7 days, which was significantly shorter than the previous average length of stay in our respiratory unit for a diagnosis of COPD exacerbation (8.52 days). The rate of hospital reentry was 17% (within the first 3 months). b) Exacerbation prevention program: 23 patients were enrolled. In this group, the number of hospital admissions decreased significantly from 5.0 1.8 to 1.7 2.4 per year (p = 0.001). Visits to the emergency department were also decreased, from 1.2 1.6 to 0.4 1.6 per patient (p = 0.05). Finally, the length of hospital stay decreased from 38 17 to 16 20 days (p = 0.0001). CONCLUSIONS: A combined use of hospital resources and home care programs which are specifically addressed to severe COPD patients can reduce the need for hospital admission.