Model-based assessment and mapping of total phosphorus enrichment in rivers with sparse reference data.

Water nutrient management efforts are frequently coordinated across thousands of water bodies, leading to a need for spatially extensive information to facilitate decision making. Here we explore potential applications of a machine learning model of river low-flow total phosphorus (TP) concentrations to support landscape nutrient management. The model was trained, validated, and then applied for all rivers of Michigan, USA to identify potential drivers of nutrient variation, predict alteration in nutrient concentrations from minimally disturbed conditions, and explore reach-specific sensitivity to riparian agricultural change. A boosted regression tree model of low-flow TP concentrations trained on natural and anthropogenic landscape predictors accounted for 53 % of variation in cross-validation data, had good accuracy, little bias, and plausible relationships between predictors and response. Percent riparian agricultural cover accounted for the greatest root mean square error reduction in the modeled response (33.2 %), followed by riparian soil permeability (12.9 %), watershed slope (9.6 %), and percent urban cover (9.6 %). An apparent non-linear relationship between TP concentrations and percent riparian agricultural cover suggested steep positive increases in stream TP concentrations between 10 and 30 % upstream riparian agricultural cover. Predicted minimally disturbed TP concentrations were spatially variable and ranged from 7.0 to 48.5 µg/L, with the highest concentrations in watersheds draining low-permeability lake plain soils. Comparison of minimally disturbed predictions to those from the early 2000s suggested that much of northern Michigan existed close to the reference condition, while southern Michigan streams were often substantially enriched. Our predicted values of minimally disturbed condition generally agreed with previous studies but offer greater geographic specificity. Expanded application of machine learning modeling with landscape predictor data have great potential to inform stream nutrient strategy development in settings with sparse reference data.

Contracture Severity at Hospital Discharge in Children: A Burn Model System Database Study.

Contractures can complicate burn recovery. There are limited studies examining the prevalence of contractures following burns in pediatrics. This study investigates contracture outcomes by location, injury, severity, length of stay, and developmental stage. Data were obtained from the Burn Model System between 1994 and 2003. All patients younger than the age of 18 with at least one joint contracture at hospital discharge were included. Sixteen areas of impaired movement from the shoulder, elbow, wrist, hand, hip, knee, and ankle joints were examined. Analysis of variance was used to assess the association between contracture severity, burn size, and length of stay. Age groupings were evaluated for developmental patterns. A P value of less than .05 was considered statistically significant. Data from 225 patients yielded 1597 contractures (758 in the hand) with a mean of 7.1 contractures (median 4) per patient. Mean contracture severity ranged from 17% (elbow extension) to 41% (ankle plantarflexion) loss of movement. Statistically significant associations were found between active range of motion loss and burn size, length of stay, and age groupings. The data illustrate quantitative assessment of burn contractures in pediatric patients at discharge in a multicenter database. Size of injury correlates with range of motion loss for many joint motions, reflecting the anticipated morbidity of contracture for pediatric burn survivors. These results serve as a potential reference for range of motion outcomes in the pediatric burn population, which could serve as a comparison for local practices, quality improvement measures, and future research.

Outsized nutrient contributions from small tributaries to a Great Lake.

Excessive nitrogen (N) and phosphorus (P) loading is one of the greatest threats to aquatic ecosystems in the Anthropocene, causing eutrophication of rivers, lakes, and marine coastlines worldwide. For lakes across the United States, eutrophication is driven largely by nonpoint nutrient sources from tributaries that drain surrounding watersheds. Decades of monitoring and regulatory efforts have paid little attention to small tributaries of large water bodies, despite their ubiquity and potential local importance. We used a snapshot of nutrient inputs from nearly all tributaries of Lake Michigan-the world's fifth largest freshwater lake by volume-to determine how land cover and dams alter nutrient inputs across watershed sizes. Loads, concentrations, stoichiometry (N:P), and bioavailability (percentage dissolved inorganic nutrients) varied by orders of magnitude among tributaries, creating a mosaic of coastal nutrient inputs. The 6 largest of 235 tributaries accounted for ∼70% of the daily N and P delivered to Lake Michigan. However, small tributaries exhibited nutrient loads that were high for their size and biased toward dissolved inorganic forms. Higher bioavailability of nutrients from small watersheds suggests greater potential to fuel algal blooms in coastal areas, especially given the likelihood that their plumes become trapped and then overlap in the nearshore zone. Our findings reveal an underappreciated role that small streams may play in driving coastal eutrophication in large water bodies. Although they represent only a modest proportion of lake-wide loads, expanding nutrient management efforts to address smaller watersheds could reduce the ecological impacts of nutrient loading on valuable nearshore ecosystems.

The impact of discharge contracture on return to work after burn injury: A Burn Model System investigation.

INTRODUCTION: Despite many advances in burn care, the development of extremity contracture remains a common and vexing problem. Extremity contractures have been documented in up to one third of severely burned patients at discharge. However, little is known about the long-term impact of these contractures. The purpose of this study was to examine the association of extremity contractures with employment after burn injury. METHODS: We obtained data from the Burn Model System database from 1994 to 2003. We included in the study cohort all adult patients who were working prior to injury and identified those discharged with and without a contracture in one of the major extremity joints (shoulder, elbow, wrist, hip, knee and ankle). We classified contracture severity according to mild, moderate and severe categories. We performed descriptive analyses and predictive modeling to identify injury and patient factors associated with return to work (RTW) at 6, 12, and 24 months. RESULTS: A total of 1,203 participant records met criteria for study inclusion. Of these, 415 (35%) had developed a contracture at discharge; 9% mild, 12% moderate, and 14% severe. Among 801 (67%) participants who had complete data at 6 months after discharge, 70% of patients without contracture had returned to work compared to 45% of patients with contractures (p < 0.001). RTW increased at each subsequent follow-up time point for the contracture group, however, it remained significantly lower than in no-contracture group (both p < 0.01). In multivariable analyses, female sex, non-Caucasian ethnicity, larger burn size, alcohol abuse, number of in-hospital operations, amputation, and in-hospital complications were associated with a lower likelihood of employment. In adjusted analyses, discharge contracture was associated with a lower probability of RTW at all 3 time points, although its impact significantly diminished at 24 months. CONCLUSIONS: This study indicates an association between discharge contracture and reduced employment 6, 12 and 24 months after burn injury. Among many other identified patient, injury, and hospitalization related factors that are barriers to RTW, the presence of a contracture at discharge adds a significant reintegration burden for working-age burn patients.

Factors Affecting Employment After Burn Injury in the United States: A Burn Model System National Database Investigation.

OBJECTIVE: To investigate the effect of patient and injury characteristics on employment for working-age, adult survivors of burn injury using the multicenter Burn Model System national database. DESIGN: Longitudinal survey. SETTING: Multicenter regional burn centers. PARTICIPANTS: Adult burn survivors (N=967) age≥18 years with known employment status prior to injury were included in the analysis at 12 months after injury. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Employment status at 12 months after injury. RESULTS: The analyses determined that those employed preinjury had higher odds of being employed (odds ratio [OR]=8.1; 95% confidence interval [CI], 4.9-13.1). White, non-Hispanic individuals were also more likely to be employed (OR=1.49; 95% CI, 1.0-2.1). Older individuals, females, those with longer hospitalizations, amputation during the acute hospitalization, and those with high pain interference at hospital discharge had lower odds of working after injury. Preinjury living situation, preinjury alcohol and drug misuse, number of acute operations and burn size (total body surface area, %) were not significant predictors of employment status at 12 months after burn injury. CONCLUSION: Preinjury employment remains the most significant predictor for postburn employment. Although past reports have focused on predictors for postburn employment, we believe that we need to seek greater understanding of modifiable risk factors for unemployment and examine issues related to work retention, performance, accommodations, and career trajectories for the working-age survivor of burn injury.

A Comparison of Contracture Severity at Acute Discharge in Patients With and Without Heterotopic Ossification: A Burn Model System National Database Study.

This study assesses the association between heterotopic ossification and upper extremity contracture by comparing goniometric measured active range of motion outcomes of patients with and without heterotopic ossification. Data were obtained from the Burn Model System National Database between 1994 and 2003 for patients more than 18 years with elbow contracture at acute discharge. Absolute losses in elbow range of motion were compared for those with and without radiologic evidence of heterotopic ossification (location undefined) and were further examined by burn size subgroups using Wilcoxon rank-sum test. Differences in elbow range of motion were estimated using regression models, adjusted for demographic and clinical variables. Loss of range of motion of shoulder, wrist, forearm, and hand were also compared. From 407 instances of elbow contracture, the subjects with heterotopic ossification were found to have greater median absolute loss of elbow flexion among all survivors (median 50° [IQR 45°] vs 20° [30°], P < .0001), for the 20 to 40% total body surface area burn subgroup (70° [20°] vs 20° [30°], P = .0008) and for the >40% subgroup (50° [45°] vs 30° [32°], P = .03). The adjusted estimate of the mean difference in the absolute loss of elbow flexion between groups was 23.5° (SE ±7.2°, P = .0013). This study adds to our understanding of the potential effect of heterotopic ossification on upper extremity joint range of motion, demonstrating a significant association between the presence of heterotopic ossification and elbow flexion contracture severity. Further study is needed to determine the functional implications of heterotopic ossification and develop treatment protocols.

Quantifying Contracture Severity at Hospital Discharge in Adults: A Burn Model System National Database Study.

Contracture is a common complication of burn injury and can cause significant barriers to functional recovery and rehabilitation. There are limited studies of quantitative range of motion after burn injury. The purpose of this study is to examine quantitative contracture outcomes by anatomical location, burn size, and length of stay in adults. Data were obtained from the Burn Model System National Database from 1994 to 2003. All adult patients with a joint contracture at acute discharge were included and 16 joint motions were examined. Contractures were reported as both mean absolute loss of normal range of motion in degrees and percent loss of normal range of motion. Analysis of variance was used to assess for a linear trend for contracture severity by burn size and length of stay. Data from 659 patients yielded 6,228 instances of contracture. Mean absolute loss of normal range of motion ranged from 20° to 65° representing an 18 to 45% loss of normal movement across the studied joint motions. In the majority of joint motions, contracture severity significantly increased with larger burn size and longer length of stay; however, wrist and many lower extremity joint movements did not demonstrate this trend. The data illustrate the quantitative assessment of range of motion deficits in adults with burn injury at discharge and the relation to burn size and length of stay.

Predictors of Discharge Disposition in Older Adults With Burns: A Study of the Burn Model Systems.

Older patients with burn injury have a greater likelihood for discharge to nursing facilities. Recent research indicates that older patients discharged to nursing facilities are two to three times as likely to die within a 3-year period relative to those discharged to home. In light of these poor long-term outcomes, we conducted this study to identify predictors for discharge to independent vs nonindependent living status in older patients hospitalized for burns. We retrospectively reviewed all older adults (age ≥ 55 years) who were prospectively enrolled in a longitudinal multicenter study of outcomes from 1993 to 2011. Patient, injury, and treatment outcomes data were analyzed. Recognizing that transfer to inpatient rehabilitation may have impacted final hospital discharge disposition: we assessed the likelihood of inpatient rehabilitation stay, based on identified predictors of inpatient rehabilitation. We subsequently performed a logistic regression analysis on the clustered, propensity-matched cohort to assess associations of burn and injury characteristics on the primary outcome of final discharge status. A total of 591 patients aged ≥55 years were treated and discharged alive from three participating U.S. burn centers during the study period. Mean burn size was 14.8% (SD 11.2%) and mean age was 66.7 years (SD 9.3 years). Ninety-three patients had an inpatient rehabilitation stay before discharge (15.7%). Significant factors predictive of inpatient rehabilitation included a burn >20% TBSA, mechanical ventilation, older age, range of motion deficits at acute care discharge, and study site. These factors were included in the propensity model. Four hundred seventy-one patients (80%) were discharged to independent living status. By matched propensity analysis, older age was significantly associated with a higher likelihood of discharge to nonindependent living (P < .01 in both the 65-74 age group and the oldest age group when compared with the 55-64 age group). Comorbidity (P < .01) and history of alcohol abuse (P < 0.01) were also predictive patient factors. Furthermore, clinical practice variations among the three study sites also constituted a significant factor in discharge disposition (both P < .01 when compared with the index study site). Older age remains an important risk factor for discharge to nonindependent living status, even after accounting for inpatient rehabilitation stay. This analysis, however, reveals significant variations in discharge disposition practices among the three participating study sites. We believe that these variations among burn centers need to be elucidated to better understand discharge disposition status in older patients with burns.

Variation in Inpatient Rehabilitation Utilization After Hospitalization for Burn Injury in the United States.

Approximately 45,000 individuals are hospitalized annually for burn treatment. Rehabilitation after hospitalization can offer a significant improvement in functional outcomes. Very little is known nationally about rehabilitation for burns, and practices may vary substantially depending on the region based on observed Medicare post-hospitalization spending amounts. This study was designed to measure variation in rehabilitation utilization by state of hospitalization for patients hospitalized with burn injury. This retrospective cohort study used nationally collected data over a 10-year period (2001 to 2010), from the Healthcare Cost and Utilization Project (HCUP) State Inpatient Databases (SIDs). Patients hospitalized for burn injury (n = 57,968) were identified by ICD-9-CM codes and were examined to see specifically if they were discharged immediately to inpatient rehabilitation after hospitalization (primary endpoint). Both unadjusted and adjusted likelihoods were calculated for each state taking into account the effects of age, insurance status, hospitalization at a burn center, and extent of burn injury by TBSA. The relative risk of discharge to inpatient rehabilitation varied by as much as 6-fold among different states. Higher TBSA, having health insurance, higher age, and burn center hospitalization all increased the likelihood of discharge to inpatient rehabilitation following acute care hospitalization. There was significant variation between states in inpatient rehabilitation utilization after adjusting for variables known to affect each outcome. Future efforts should be focused on identifying the cause of this state-to-state variation, its relationship to patient outcome, and standardizing treatment across the United States.

An expanded delivery model for outpatient burn rehabilitation.

Despite the numerous multidisciplinary services burn centers provide, a number of challenges to obtaining optimal outcomes exist. The goal of this study was to overcome the barriers to effective burn rehabilitation by utilizing an expanded care coordinator (ECC) to supplement the existing outpatient services. In this between-group, single-blind, randomized, controlled trial, the control group (n = 41) received standard outpatient care and the experimental group (n = 40) received additional services provided by the ECC, including telephone calls at set intervals (24 hours postdischarge, 2, 4, 8, 12 weeks postdischarge and 5, 7, 9 months postdischarge). The ECC was trained in motivational interviewing, crisis intervention, and solution-focused counseling. He assisted patients before and after each clinic visit, coordinated outpatient services in their geographic area (physical and occupational therapy, counseling, primary care provider referrals, etc.), and helped develop problem-solving approaches to accomplish individualized goals. Outcome measures included patient identified goals utilizing the goal attainment scale, the urn-specific health scale-brief, the Short Form 12, a patient satisfaction survey, and a return to work survey. The average subject age was 43 years (SD = 16.9) with a mean TBSA of 19% (SD = 18.8). The average length of hospitalization was 36 days (SD = 42.9). The patient and injury characteristics were similar between the study groups. For the experimental group, 33% completed seven calls, with 23% completing all the eight calls. All were assessed using general linear models and were adjusted for sex, age, length of hospitalization, urban vs rural area of residence, %TBSA burn, and ethnicity. There was no difference between the control and experimental groups for any of the outcome measures at either 6 or 12 months postburn. No differences in outcomes between the groups were found. All participants appreciated the individualized goal setting process that was used as an outcome measure and this may have accounted for the similar outcomes in both the groups. (The measure may have been more of an intervention, thus contributing to the strength of the control group.) Although most patients with burn injuries may not need an intervention that is this intensive, a subset of patients at higher risk or with more severe injuries may benefit from more intensive and personalized services. Future research should examine the benefits of individual goal setting processes for all the patients and also attempt to identify those patients most at risk for poorer outcomes and therefore, likely to benefit of more intensive personalized services.

Elevated energy coupling and aerobic capacity improves exercise performance in endurance-trained elderly subjects.

Increased maximal oxygen uptake (V(O(2)max)), mitochondrial capacity and energy coupling efficiency are reported after endurance training (ET) in adult subjects. Here we test whether leg exercise performance (power output of the legs, P(max), at V(O(2)max)) reflects these improvements with ET in the elderly. Fifteen male and female subjects were endurance trained for a 6 month programme, with 13 subjects (69.5 ± 1.2 years old, range 65-80 years old; n = 7 males; n = 6 females) completing the study. This training significantly improved P(max) (Δ17%; P = 0.003), V(O(2)max) (Δ5.4%; P = 0.021) and the increment in oxygen uptake (V(O(2))) above resting (ΔV(O(2)m-r) = V(O(2)max) - V(O(2)rest; Δ9%; P < 0.02). In addition, evidence of improved energy coupling came from elevated leg power output per unit V(O(2))at the aerobic capacity [Δ(P(max)/ΔV(O(2)m-r)); P = 0.02] and during submaximal exercise in the ramp test as measured by delta efficiency (ΔP(ex)/ΔV(O(2)); P = 0.04). No change was found in blood lactate, muscle glycolysis or fibre type. The rise in P(max) paralleled the improvement in muscle oxidative phosphorylation capacity (ATP(max)) in these subjects. In addition, the greater exercise energy coupling [Δ(P(max)/ΔV(O(2)m-r)) and delta efficiency] was accompanied by increased mitochondrial energy coupling as measured by elevated ATP production per unit mitochondrial content in these subjects. These results suggest that leg exercise performance benefits from elevations in energy coupling and oxidative phosphorylation capacity at both the whole-body and muscle levels that accompany endurance training in the elderly.

Harborview burns--1974 to 2009.

BACKGROUND: Burn demographics, prevention and care have changed considerably since the 1970s. The objectives were to 1) identify new and confirm previously described changes, 2) make comparisons to the American Burn Association National Burn Repository, 3) determine when the administration of fluids in excess of the Baxter formula began and to identify potential causes, and 4) model mortality over time, during a 36-year period (1974-2009) at the Harborview Burn Center in Seattle, WA, USA. METHODS AND FINDINGS: 14,266 consecutive admissions were analyzed in five-year periods and many parameters compared to the National Burn Repository. Fluid resuscitation was compared in five-year periods from 1974 to 2009. Mortality was modeled with the rBaux model. Many changes are highlighted at the end of the manuscript including 1) the large increase in numbers of total and short-stay admissions, 2) the decline in numbers of large burn injuries, 3) that unadjusted case fatality declined to the mid-1980s but has changed little during the past two decades, 4) that race/ethnicity and payer status disparity exists, and 5) that the trajectory to death changed with fewer deaths occurring after seven days post-injury. Administration of fluids in excess of the Baxter formula during resuscitation of uncomplicated injuries was evident at least by the early 1990s and has continued to the present; the cause is likely multifactorial but pre-hospital fluids, prophylactic tracheal intubation and opioids may be involved. CONCLUSIONS: 1) The dramatic changes include the rise in short-stay admissions; as a result, the model of burn care practiced since the 1970s is still required but is no longer sufficient. 2) Fluid administration in excess of the Baxter formula with uncomplicated injuries began at least two decades ago. 3) Unadjusted case fatality declined to ∼6% in the mid-1980s and changed little since then. The rBaux mortality model is quite accurate.

Preinjury alcohol and drug use among persons with spinal cord injury: implications for rehabilitation.

CONTEXT/OBJECTIVE: To describe preinjury alcohol and drug use and opportunities for secondary prevention among persons with recent spinal cord injury (SCI). DESIGN: Survey. SETTING: Acute inpatient rehabilitation program. PARTICIPANTS: Participants were 118 (84.8%) of 139 consecutive admissions who met inclusion criteria and were screened for preinjury alcohol and drug use. INTERVENTIONS: None. OUTCOME MEASURES: Alcohol and drug use, toxicology results, alcohol problems, readiness to change, and treatment preferences. RESULTS: Participants were on average 37 years old, 84% were men, and 85% were white. Fifty-one percent of the sample was considered 'at-risk' drinkers. Significant lifetime alcohol-related problems were reported by 38% of the total sample. Thirty-three percent reported recent illicit drug use and 44% of the 82 cases with toxicology results were positive for illicit drugs. Seventy-one percent of at-risk drinkers reported either considering changes in alcohol use or already taking action. Forty-one percent reported interest in trying substance abuse treatment or Alcoholics Anonymous (AA). Motivation to change alcohol use was significantly and positively associated with self-reported indicators of alcohol problem severity. CONCLUSION: Preinjury alcohol and drug abuse are common among persons with recent SCI. Substance abuse screening is feasible and detects not only salient clinical problems but also significant motivation to change and interest in AA or treatment, all of which represent an important window of opportunity for appropriate brief interventions and referrals. In contrast with the idea that alcoholism is a 'disease of denial', the majority of at-risk drinkers with new onset SCI indicate they are considering making changes.

Community integration outcome after burn injury.

It is important to focus on community integration, including return to work and school, early during treatment after burn injuries. A careful analysis of the potential barriers to return to activities can help focus a treatment team and provide appropriate support for a return to work or school plan. Psychological intervention is often an important component of a return to work or school plan. Vocational rehabilitation counselors and school reentry coordinators are valuable assets to coordinating with a treatment team and communicating with a workplace or school. A successful return to work or school is often achieved with a coordinated and supportive approach.

Clinical competencies for burn rehabilitation therapists.

Nationally agreed-upon standards for competence are needed for burn physical and occupational rehabilitation therapists (BRTs) to define what constitutes safe and competent burn rehabilitation practice. Currently, consensus regarding the knowledge and skill components needed for the training and evaluation of BRT job performance is lacking. The Rehabilitation Committee of the American Burn Association used a staged, multimethod approach and input from more than 25 experts in the burn rehabilitation community to develop competency standards for BRTs. The result was the "Burn Rehabilitation Therapist Competency Tool" (BRTCT) that defines competency domains required of BRTs to provide physical and occupational therapy to patients with burn injury during their initial acute hospitalization and rehabilitation. This article describes the staged development and validation of the BRTCT. The component parts of the tool itself are presented, and the recommendations for assessment of competence are discussed. The BRTCT provides a common framework and language for expectations of performance in burn rehabilitation. Development of the BRTCT is a critical step in the ongoing process of promoting professional development and consistent practice standards in burn rehabilitation.