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Objective The contribution of bacterial co-infection to critical illness associated with 2009 influenza A (H1N1) [pH1N1] virus infection remains uncertain. The objective of this study was to determine if bacterial co-infection increased the morbidity and mortality of pH1N1. Design Retrospective and Prospective cohort study Setting 35 adult U.S. intensive care units over the course of one year Patients 683 critically ill adults with confirmed or probable pH1N1 Interventions None Measurements and Main Results A confirmed or probable case was defined as a positive pH1N1 test result or positive test for influenza A that was otherwise not subtyped. Bacterial co-infection was defined as documented bacteremia or any presumed bacterial pneumonia with or without positive respiratory tract culture within 72 hours of ICU admission. The mean age was 45±16 years, mean BMI 32.5±11.1 kg/m2, and mean APACHE II score 21±9, with 76% having at least one co-morbidity. Of 207 (30.3%) patients with bacterial co-infection on ICU admission, 154 had positive cultures with Staphylococcus aureus (n=57) and Streptococcus pneumoniae (n=19) the most commonly identified pathogens. Bacterial co-infected patients were more likely to present with shock (21 vs. 10%; P=0.0001), require mechanical ventilation at the time of ICU admission (63 vs. 52%; P=0.005) and have longer duration of ICU care (median 7 vs. 6 days; P=0.05). Hospital mortality was 23%; 31% in bacterial co-infected patients and 21% in patients without co-infection (P=0.002). Immunosuppression (RR 1.57; 95% CI 1.20–2.06; P=0.0009) and Staphylococcus aureus at admission (RR 2.82; 95% CI: 1.76–4.51; P<0.0001) were independently associated with increased mortality. Conclusions Among ICU patients with pH1N1, bacterial co-infection diagnosed within 72 hours of admission, especially with Staphylococcus aureus, was associated with significantly higher morbidity and mortality.

Objective Delirium duration is predictive of long-term cognitive impairment (LTCI) in Intensive Care Unit (ICU) survivors. Hypothesizing that a neuroanatomical basis may exist for the relationship between delirium and LTCI, we conducted this exploratory investigation of the associations between delirium duration, brain volumes and LTCI. Design, Setting, and Patients A prospective cohort of medical and surgical ICU survivors with respiratory failure or shock. Measurements Quantitative high resolution 3-Tesla brain magnetic resonance imaging was used to calculate brain volumes at discharge and three-month follow-up. Delirium was evaluated using the Confusion Assessment Method for the ICU; cognitive outcomes were tested at three- and twelve-month follow-up. Linear regression was used to examine associations between delirium duration and brain volumes, and between brain volumes and cognitive outcomes. Results A total of 47 patients completed the MRI protocol. Patients with longer duration of delirium displayed greater brain atrophy as measured by a larger ventricle-to-brain ratio (VBR) at hospital discharge [0.76, 95% confidence intervals (CI) (0.10, 1.41); p=0.03] and at 3-month follow-up [0.62 (0.02, 1.21), p=0.05]. Longer duration of delirium was associated with smaller superior frontal lobe [−2.11 cm3 (−3.89, −0.32); p=0.03] and hippocampal volumes at discharge [−0.58 cm3 (−0.85, −0.31), p<0.001] – regions responsible for executive functioning and memory, respectively. Greater brain atrophy (higher VBR) at three months was associated with worse cognitive performances at twelve months [lower RBANS battery score −11.17 (−21.12, −1.22), p=0.04]. Smaller superior frontal lobes, thalamus, and cerebellar volumes at three months were associated with worse executive functioning and visual attention at twelve months. Conclusions These preliminary data show that longer duration of delirium is associated with smaller brain volumes up to three months after discharge, and that smaller brain volumes are associated with LTCI up to 12 months. We cannot, however, rule out that smaller preexisting brain volumes explain these findings.

Objective Early mobility in mechanically ventilated patients is safe, feasible, and may improve functional outcomes. We sought to determine the prevalence and character of mobility for intensive care unit (ICU) patients with acute respiratory failure in US ICUs. Design Two-day multicenter point prevalence study Patients Adult patients (≥ 18 years old) with acute respiratory failure requiring mechanical ventilation in 17 US hospitals and 42 ICUs. Interventions We defined therapist-provided mobility as the proportion of patient-days with any physical (PT) or occupational therapy (OT) provided mobility event. Hierarchical regression models were used to identify predictors of out of bed mobility. Measurements and Main Results Hospitals contributed 770 patient-days of data. Patients received mechanical ventilation on 73% of the patient-days mostly (n=432, 56%) ventilated via an endotracheal tube. The prevalence of PT/OT-provided mobility was 32% (247/770), with a significantly higher proportion of non-mechanically ventilated patients receiving PT/OT (48% vs. 26%, p=<0.001). Patients on mechanical ventilation achieved out of bed mobility on 16% (n=90) of the total patient-days. PT/OT involvement in mobility events was strongly associated with progression to out of bed mobility (OR 29.1, CI 15.1 – 56.3, p≤0.001). Presence of an endotracheal tube and delirium were negatively associated with out of bed mobility. Conclusions In a cohort of hospitals caring for acute respiratory failure patients, PT/OT-provided mobility was infrequent. PT/OT involvement in mobility was strongly predictive of achieving greater mobility levels in patients with respiratory failure. Mechanical ventilation via an endotracheal tube and delirium are important predictors of mobility progression.

Shock is an often lethal syndrome of diminished or insuffi cient perfusion that impairs organ function. Generally associated with decreased arterial blood pressure, shock results most commonly from sepsis, hemorrhage, or primary cardiac failure. 1 Vasopressor medications, largely vasoactive catecholamine hormones, have been used for many decades in the treatment of hypotensive shock. These medications have not been subjected to rigorous, placebo-controlled studies, and consensus from clinical experience suggests that there is not equipoise for such a study in most cases of shock. 2 When vascular tone is profoundly diminished (eg, vasoplegic syndrome or distributive shock), patients may require high-dose vasopressor therapy (HDV).Background: Some patients with hypotensive shock do not respond to usual doses of vasopressor therapy. Very little is known about outcomes after high-dose vasopressor therapy (HDV). We sought to characterize survival among patients with shock requiring HDV. We also evaluated the possible utility of stress-dose corticosteroid therapy in these patients.

Objective Evidence is emerging that delirium duration is a predictor of long-term cognitive impairment (LTCI) in Intensive Care Unit (ICU) survivors. Relationships between (a) delirium duration and brain white matter integrity, and (b) between white matter integrity and LTCI are poorly understood and could be explored using Magnetic Resonance Imaging (MRI). Design, Setting, Patients A two-center, prospective cohort study incorporating delirium monitoring, neuroimaging and cognitive testing in ICU survivors. Measurements Delirium was evaluated with the Confusion Assessment Method for the ICU (CAM-ICU) and cognitive outcomes were tested at 3 and 12-month follow-up. Following the ICU stay, Fractional Anisotropy (FA), a measure of white matter integrity, was calculated quantitatively using Diffusion Tensor Imaging (DTI) with a 3-Tesla MRI scanner at hospital discharge and three-month follow-up. We examined associations between (a) delirium duration and FA and (b) between FA and cognitive outcomes using linear regression adjusted for age and sepsis. Results A total of 47 patients with median age of 50 years completed the DTI-MRI protocol. Greater duration of delirium (3 vs. 0 days) was associated with lower FA (i.e. reduced FA=white matter disruption) in the genu (−0.02; p = 0.04) and splenium (−0.01; p = 0.02) of the corpus callosum and anterior limb of the internal capsule (−0.02; p = 0.01) at hospital discharge. These associations persisted at 3 months for the genu (−0.02; p= 0.02) and splenium (−0.01; p= 0.004). Lower FA in the anterior limb of internal capsule at discharge (−10.35; p= 0.05) and in genu of corpus callosum at three months (−8.81; p = 0.006) was associated with worse cognitive scores at 3 and 12 months. Conclusions In this pilot investigation, delirium duration in the ICU was associated with white matter disruption at both discharge and 3 months. Similarly, white matter disruption was associated with worse cognitive scores up to 12 months later. This hypothesis-generating investigation may help design future studies to explore these complex relationships in greater depth.

Total severe sepsis and septic shock bundle compliances increased substantially and were associated with a marked reduction in hospital mortality after adjustment for age, severity of illness, and comorbidities in a multicenter ICU cohort. Early resuscitation bundle element compliance predicted ineligibility for subsequent bundle elements.

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