Kathleen S Romanowski

During host injury, Pseudomonas aeruginosa can be cued to express a lethal phenotype within the intestinal tract reservoir-a hostile, nutrient scarce environment depleted of inorganic phosphate. Here we determined if phosphate depletion activates a lethal phenotype in P. aeruginosa during intestinal colonization. To test this, we allowed Caenorhabditis elegans to feed on lawns of P. aeruginosa PAO1 grown on high and low phosphate media. Phosphate depletion caused PAO1 to kill 60% of nematodes whereas no worms died on high phosphate media. Unexpectedly, intense redness was observed in digestive tubes of worms before death. Using a combination of transcriptome analyses, mutants, and reporter constructs, we identified 3 global virulence systems that were involved in the "red death" response of P. aeruginosa during phosphate depletion; they included phosphate signaling (PhoB), the MvfR-PQS pathway of quorum sensing, and the pyoverdin iron acquisition system. Activation of all 3 systems was required to form a red colored PQS+Fe(3+) complex which conferred a lethal phenotype in this model. When pyoverdin production was inhibited in P. aeruginosa by providing excess iron, red death was attenuated in C. elegans and mortality was decreased in mice intestinally inoculated with P. aeruginosa. Introduction of the red colored PQS+Fe(3+) complex into the digestive tube of C. elegans or mouse intestine caused mortality associated with epithelial disruption and apoptosis. In summary, red death in C. elegans reveals a triangulated response between PhoB, MvfR-PQS, and pyoverdin in response to phosphate depletion that activates a lethal phenotype in P. aeruginosa.

The ABA pain guidelines were developed 14 years ago and have not been revised despite evolution in the practice of burn care. A sub-committee of the American Burn Association's Committee on the Organization and Delivery of Burn Care was created to revise the adult pain guidelines. A MEDLINE search of English-language publications from 1968 to 2018 was conducted using the keywords "burn pain," "treatment," and "assessment." Selected references were also used from the greater pain literature. Studies were graded by two members of the committee using Oxford Centre for Evidence-based Medicine-Levels of Evidence. We then met as a group to determine expert consensus on a variety of topics related to treating pain in burn patients. Finally, we assessed gaps in the current knowledge and determined research questions that would aid in providing better recommendations for optimal pain management of the burn patient. The literature search produced 189 papers, 95 were found to be relevant to the assessment and treatment of burn pain. From the greater pain literature 151 references were included, totaling 246 papers being analyzed. Following this literature review, a meeting to establish expert consensus was held and 20 guidelines established in the areas of pain assessment, opioid medications, nonopioid medications, regional anesthesia, and nonpharmacologic treatments. There is increasing research on pain management modalities, but available studies are inadequate to create a true standard of care. We call for more burn specific research into modalities for burn pain control as well as research on multimodal pain control.

PURPOSE: Clinicians anecdotally noted that elderly patients who suffered from traumatic injuries (falls or other injuries) often re-present and are readmitted with fall injuries. Herein, we hypothesized that fall injuries and fall-related deaths and readmissions are increasing over time, and assessed whether the overall rates of death, hospital admission, and 30-day readmission due to falls increased from 2010 to 2014 in the elderly population (≥65) in the US. PATIENTS AND METHODS: The WHO mortality database and the National Readmission Database (NRD) were queried to assess rates of deaths and hospital admissions and 30-day readmissions associated with fall injuries in the elderly population that presented with trauma. Descriptive statistics were obtained. The generalized linear mixed modeling (GLMM) framework was utilized to examine the relationship between fixed-effect predictor variables and the dichotomous outcome, indicating readmission within 30 days of previous discharge while accounting for hospital clustering with a random intercept. RESULTS: Fall-related death increased by 1.4% from 2010 to 2014. Similarly, the hospital admission rate increased by 2% and was mainly associated with increased admission of elderly 65-74 years old. Approximately 55% of the fall patients were placed in nursing facilities in 2010, and this rate increased by 3% from 2010 to 2014. Thirty-day readmission rates for fall and trauma patients remained stable from 2010 to 2014. However, the rate of fall patients readmitted within 30 days for a subsequent fall increased from 15.6% to 17.4% between 2010 and 2014. CONCLUSION: Our data indicate a steady increase in deaths and admissions for fall injuries in the elderly population. Strikingly, the incidence of readmission for a subsequent fall is increasing. With the aging population, this trend is likely to continue and highlights the need for elderly social support systems and fall prevention programs.

With longer life expectancy, the number of burn injuries in the elderly continues to increase. Prediction of outcomes for the elderly is complicated by preinjury physical fitness and comorbid illness. The authors hypothesize that admission frailty assessment would be predictive of outcomes in the elderly burn population. Our primary aim was to determine if higher frailty scores were associated with higher risk of mortality for elderly burn patients. The secondary aims were to assess if higher frailty scores were associated with increased length of stay, increased needs for mechanical ventilation and poor discharge disposition. A 2-year retrospective chart review was performed of all admitted acute burn patients 65 years or older. Data collected included: age, gender, %TBSA of burn injury, presence of inhalation injury, in hospital mortality, hospital length of stay, ventilator days, ICU length of stay, surgical procedures, insurance status, and discharge disposition. Frailty scores were assessed from admission data and calculated using the Canadian Study of Health and Aging clinical frailty scale. A total of 89 patients met entry criteria. Mean age was 75.3 ± 8.1 years and consisted of 62 men and 27 women. Mean %TBSA was 9.6 ± 9.1% and mean frailty score (FS) was 4.5 ± 1.2. Eighty patients survived to discharge and nine died. Nonsurvivors had significantly higher FS compared to survivors (5.2 ± 1.2 vs 4.4 ± 1.2). FS were also significantly higher in patients discharged to skilled nursing facilities (SNF) (5.34 ± 0.9) compared to those who were discharged home (4.1 ± 1.2) or to physical rehabilitation facilities (4 ± 1.5). Multivariate linear regression analysis revealed that age (B = 0.04) and discharge to SNF (B = 1.2) are independently associated with higher FS. However, survivors were independently associated with a significantly lower FS (B = -1.3). Multivariate logistic regression analysis revealed high admission FS independently increased the risk of discharge to SNF (odds ratio of 2.5 [1.3-4.8, 95% confidence interval]) and increased the risk of mortality (odds ratio of 1.67 [1.01-2.7, 95% confidence interval]). Frailty scores on admission allow for a more complete assessment of elderly patients and can be used to establish benchmark models for burn injury outcomes. In addition FS can be used as a research tool to improve outcomes for elderly burn injured patients.