Much attention has been devoted in the literature to the details of sepsis pathophysiology and therapy over the last decade, while severe sepsis and septic shock remain the number one cause of death in critically ill patients. The failure of numerous randomized controlled trials for interventions in severe sepsis has led some to believe that little progress has been made in terms of improving survival. Kaukonen and colleagues sought to estimate trends in mortality in a large cohort of patients in Australia and New Zealand over a 13-year period. The authors hypothesized that mortality rates decreased significantly throughout this time period. Their study affirmed similar findings of decreased mortality among patients with severe sepsis over the last decade. However, the study also demonstrated a decrease in overall mortality among all admitting ICU diagnoses over the same time period. This mortality reduction remained after multiple adjustments for confounders, including illness severity. These findings likely reflect a better understanding of disease processes and therapies in the ICU, whether related to sepsis or not. One potential criticism of this work is that an element of surveillance bias or stage migration (i.e., the Will Rogers phenomenon) might be at play given improved awareness and detection of sepsis. With the decrease in short-term mortality observed in this study and others, future studies examining measures of healthcare-related quality of life and other measures of morbidity are merited.
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Modern intensive care unit interventions such as low-tidal volume mechanical ventilation may result in short-term improvements in acute respiratory distress syndrome (ARDS) survival, but less is known about the epidemiology of long-term survival. Chen Wang et al conducted a study to quantify the gap between in-hospital and 1-year ARDS mortality rates, and to identify risk factors and causes of death at one year among patients with ARDS.
Patients were selected from an ongoing prospective, multi-unit acute lung injury (ALI) biomarker study (VALID) at a single institution (Vanderbilt University Medical Center, Nashville, TN, USA). Those who met the American European Consensus Committee criteria for ALI/ARDs were included. A sensitivity analysis was also performed to include patients who met the Berlin criteria for ARDS. All were followed until death or for at least 1 year after study enrollment. Logistic regression was used to analyze associations between risk factors and death.
The International Observational Study Investigators are looking at mechanical ventilation (MV) discontinuation practices internationally in intensive care units. The goal of the study is to characterize practice variation in weaning critically ill adults from invasive MV, as well as the influence of selected discontinuation strategies on important outcomes. Each unit will be asked to collect data on at least 10 consecutive discontinuation events — one event (e.g., tracheostomy, direct extubation, initial successful spontaneous breathing trial) per patient receiving invasive ventilation for at least 24 hours and all patients who die before any attempt at MV discontinuation. Those interested in participating should email firstname.lastname@example.org.
Although anemia may cause an increase in morbidity and mortality rates in critically ill pediatric patients, transfusion of packed red blood cells (pRBCs) carries significant risks, which have also been demonstrated in pediatric cardiac surgery patients. However, studies related to these risks have had problems with confounding and the use of pRBCs that were not leukoreduced. Kneyber et al address these concerns in their study testing whether transfusion of leukocyte-depleted pRBCs within the first 48 hours after cardiac surgery would be independently associated with prolonged duration of mechanical ventilation. Results were published in the March 2013 issue of Pediatric Critical Care Medicine.
Kneyber and colleagues retrospectively analyzed data from 335 children between the ages of 0 months to 18 years who underwent cardiac surgery between 2007 and 2010. Of these subjects, 111 were transfused, 86 of them within the first 48 hours of admission to the pediatric intensive care unit. The author then compared the outcomes of these 86 patients to those of the 249 who were not transfused within 48 hours. Patients who received pRBCs within the first 48 hours had a longer duration of ventilation and inotropic support, longer ICU stay, and a higher rate of ventilator-associated pneumonia. However, after adjusting for the severity of illness, the transfusion of pRBCs within the first 48 hours remained independently associated with only the prolonged duration of mechanical ventilation. This study provides more evidence against arbitrary decisions to transfuse blood products. Prospective studies are necessary to determine which transfusion triggers will provide more benefit than cost. Read the full Concise Critical Appraisal.