Institution of an emergency department "swarming" care model and sepsis door-to-antibiotic time: A quasi-experimental retrospective analysis.

BACKGROUND:Prompt sepsis treatment is associated with improved outcomes but requires a complex series of actions by multiple clinicians. We investigated whether simply reorganizing emergency department (ED) care to expedite patients' initial evaluation was associated with shorter sepsis door-to-antibiotic times. METHODS:Patients eligible for this retrospective study received IV antibiotics and demonstrated acute organ failure after presenting to one of three EDs in Utah. On May 1, 2016, the intervention ED instituted "swarming" as the default model for initial evaluation of all mid- and low-acuity patients. Swarming involved simultaneous patient evaluation by the ED physician, nurse, and technician followed by a team discussion of the initial care plan. Care was unchanged at the two control EDs. A 30-day wash-in period separated the baseline (May 16, 2015 to April 15, 2016) and post-intervention (May 16, 2016 to November 15, 2016) analysis periods. We conducted a quasi-experimental analysis comparing door-to-antibiotic time for sepsis patients at the intervention ED after versus before care reorganization, applying difference-in-differences methods to control for trends in door-to-antibiotic time unrelated to the studied intervention and multivariable regression to adjust for patient characteristics. RESULTS:The analysis included 3,230 ED sepsis patients, including 1,406 from the intervention ED. Adjusted analyses using difference-in-differences methods to control for temporal trends unrelated to the studied intervention revealed no significant change in door-to-antibiotic time after care reorganization (-7 minutes, 95% CI -20 to 6 minutes, p = 0.29). Multivariable pre/post analyses using data only from the intervention ED overestimated the magnitude and statistical significance of outcome changes associated with ED care reorganization. CONCLUSIONS:Implementation of an ED care model involving parallel multidisciplinary assessment and early team discussion of the care plan was not associated with improvements in mid- and low-acuity sepsis patients' door-to-antibiotic time after accounting for changes in the outcome unrelated to the studied intervention

Gut Mucosal and Plasma Concentrations of Glutamine: A Comparison between Two Enriched Enteral Feeding Solutions in Critically Ill Patients

BACKGROUND: Addition of glutamine to enteral nutrition formulas is consistently associated with a significant decrease in septic morbidity in critically ill patients, possibly related to the attenuation of gut dysfunction. This pilot study was undertaken to compare the effects of enteral administration of two glutamine-enriched formulas containing either additional free glutamine or glutamine-rich proteins, with a standard solution on plasma and mucosal concentrations of glutamine in patients admitted in the Department of Intensive Care. METHODS: Following randomization, glutamine concentration was determined in endoscopically sampled duodenal biopsies and plasma, before and after a 7-day period of continuous administration of the designated solution. RESULTS: The mucosal concentration of glutamine increased in the duodenal biopsies sampled from patients randomized to the solution containing the glutamine-rich proteins (from 3.6 +/- 2.2 to 6.7 +/- 5.2 micro-mol/g protein), but not from the others. There were no differences between the 3 groups in the plasma concentrations of glutamine, which remained stable over time. CONCLUSION: The source of supplemental glutamine can influence gut mucosal glutamine concentrations, suggesting differences in its availability or utilization

Toward improved myocardial maturity in an organ-on-chip platform with immature cardiac myocytes

In vitro studies of cardiac physiology and drug response have traditionally been performed on individual isolated cardiomyocytes or isotropic monolayers of cells that may not mimic desired physiological traits of the laminar adult myocardium. Recent studies have reported a number of advances to Heart-on-a-Chip platforms for the fabrication of more sophisticated engineered myocardium, but cardiomyocyte immaturity remains a challenge. In the anisotropic musculature of the heart, interactions between cardiac myocytes, the extracellular matrix (ECM), and neighboring cells give rise to changes in cell shape and tissue architecture that have been implicated in both development and disease. We hypothesized that engineered myocardium fabricated from cardiac myocytes cultured in vitro could mimic the physiological characteristics and gene expression profile of adult heart muscle. To test this hypothesis, we fabricated engineered myocardium comprised of neonatal rat ventricular myocytes with laminar architectures reminiscent of that observed in the mature heart and compared their sarcomere organization, contractile performance characteristics, and cardiac gene expression profile to that of isolated adult rat ventricular muscle strips. We found that anisotropic engineered myocardium demonstrated a similar degree of global sarcomere alignment, contractile stress output, and inotropic concentration-response to the β-adrenergic agonist isoproterenol. Moreover, the anisotropic engineered myocardium exhibited comparable myofibril related gene expression to muscle strips isolated from adult rat ventricular tissue. These results suggest that tissue architecture serves an important developmental cue for building in vitro model systems of the myocardium that could potentially recapitulate the physiological characteristics of the adult heart. Impact statement With the recent focus on developing in vitro Organ-on-Chip platforms that recapitulate tissue and organ-level physiology using immature cells derived from stem cell sources, there is a strong need to assess the ability of these engineered tissues to adopt a mature phenotype. In the present study, we compared and contrasted engineered tissues fabricated from neonatal rat ventricular myocytes in a Heart-on-a-Chip platform to ventricular muscle strips isolated from adult rats. The results of this study support the notion that engineered tissues fabricated from immature cells have the potential to mimic mature tissues in an Organ-on-Chip platform