Improved functional outcome for severely injured children treated at pediatric trauma centers.

BACKGROUND: Controversy exists regarding the impact of pediatric trauma centers (PTC) on survival for injured children. However, functional outcome for children treated at PTC compared with adult trauma centers (ATC) has not been evaluated. METHODS: An analysis of children entered in the Pennsylvania Trauma Outcome Study between 1993 and 1997 was conducted. Patients were stratified according to type of trauma center: PTC; Level I ATC; Level II ATC; or ATC with added qualifications (AQ). Functional outcome at discharge was analyzed. RESULTS: For severely injured children, there was an overall trend toward improved functional outcome at PTC compared with ATC AQ and ATC I, but no difference compared with ATC II. PTC showed improved functional outcome at discharge for head injury compared with ATC AQ and ATC I. CONCLUSION: There is an overall trend toward improved functional outcome at discharge for children treated at PTC compared with those treated at ATC AQ and ATC I. Improved outcome for head injury may be a key factor contributing to improved outcome at PTC.

Intestinal cytokine gene expression in infants with acute necrotizing enterocolitis: interleukin-11 mRNA expression inversely correlates with extent of disease.

BACKGROUND/PURPOSE: The authors have shown previously that surgical specimens from infants with acute necrotizing enterocolitis (NEC) show upregulation of inducible nitric oxide (NO) synthase (iNOS) and interferon-gamma mRNA. However, the contribution of other inflammatory cytokines such as interleukin-8 (IL-8), IL-11, and IL-12 has not been defined. Likewise, the role of GTP-cyclohydrolase, the rate-limiting enzyme in tetrahydrobiopterin synthesis, and thus NO production by iNOS is unclear. In this study, the authors sought to further define the pattern of cytokine expression seen in infants with acute NEC. METHODS: The authors measured intestinal cytokine mRNA expression by semiquantitative reverse transcriptase polymerase chain reaction in 21 infants with histologically confirmed NEC, 18 with other inflammatory conditions, and in 9 patients without intestinal inflammation. Guanosine triphosphate-cyclohydrolase (GTP-CH) activity was measured by specific enzyme assay. Univariate exact logistic regression analysis was performed to identify predictors of outcome. RESULTS: IL-8 and IL-11 mRNA were upregulated in patients with acute NEC compared with those with other inflammatory conditions or those without disease; these levels returned to baseline at the time of stoma closure. Increased IL-11 mRNA decreased the likelihood of pan-necrosis (odds ratio, 0.93; P =.002). Increased IL-12 levels (but not IL-8) seemed to protect against pan-necrosis (odds ratio, 0.70; P =.06). CONCLUSIONS: Local upregulation of IL-11 may represent an adaptive response designed to limit the extent of intestinal damage in NEC. Decreased IL-12 levels may contribute to the pathogenesis of NEC by allowing bacteria to escape host defenses.

Utilizing multiple vital status tracing services optimizes mortality follow-up in large cohort studies.

PURPOSE: To compare the three national-scale death identification services used in our two-stage vital status tracing protocol, Pension Benefit Information Company (PBI), Social Security Administration (SSA), and the Health Care Financing Administration (HCFA), with respect to death identification and confirmation rate, and relevant demographic variables. METHODS: Information on 31,223 subjects with unconfirmed vital status in an ongoing occupational cohort mortality study was simultaneously submitted to PBI, SSA, and HCFA to identify subjects deceased as of December 31, 1992. Subjects whose dates of death were between 1979 and 1992 were then sent to the National Death Index (NDI) to obtain death certificate numbers and supplemental states of death. RESULTS: PBI identified and confirmed the highest number deaths in this cohort. PBI and SSA identified a higher proportion of deaths for persons who died in earlier years and/or who died at a younger age, for both confirmed and unconfirmed deaths. HCFA identified fewer deaths overall and had a smaller proportion of unconfirmed deaths. These deaths occurred in later years among older subjects and had the highest proportion of females. NDI provided exact matches for 92-96% of deaths identified by each of the three services. CONCLUSIONS: PBI was the most comprehensive service, especially for identifying younger subjects and those with an earlier date of death, while HCFA may help to identify deceased female subjects. SSA data can be purchased and used for periodic updates or interactively to identify deaths among subjects with poor identifiers (such as incorrect or missing social security numbers or misspelled names). Because each service makes a valuable contribution to the identification of deceased cohort subjects, all three should be considered for optimal mortality follow-up.

Development of a novel age-specific pediatric trauma score.

BACKGROUND/PURPOSE: Trauma scoring systems are needed to provide efficient triage of injured patients and to assess differences in outcomes and quality of care between different trauma centers. Current scoring systems used in pediatric trauma are not age specific, and thus have significant limitations. METHODS: The authors queried the Pennsylvania Trauma Outcome Study for all children 0 to 16 years entered in the database from 1993 to 1996. Age-specific threshold values for systolic blood pressure, pulse, and respiratory rate were established. Using coded scores for these age-specific values and Glasgow Coma Scale, an age-specific pediatric trauma score (ASPTS) was derived. Triage ASPTS (T-ASPTS) consisted of the integer sum of coded scores for the 4 variables, whereas ASPTS was calculated using weighted coefficients derived from logistic regression for each variable. RESULTS: T-ASPTS correlated with mortality rate. Using a threshold score of less than 10, T-ASPTS predicted mortality rate with a sensitivity of 96.97% and a specificity of 88.83%. T-ASPTS predicted mortality rate and percentage of patients with Injury Severity Score greater than 20 with similar sensitivity to the Revised Trauma Score (RTS), but T-ASPTS was more specific. The ASPTS predicted probability of survival more accurately than the RTS. CONCLUSIONS: ASPTS performs favorably as both a triage score and as a tool for predicting probability of survival for outcomes analysis. Further comparisons to existing trauma scores are needed to verify the utility of ASPTS.

Impact of pediatric trauma centers on mortality in a statewide system.

BACKGROUND: Regional pediatric trauma centers (PTC) were established to optimize the care of injured children. However, because of the relative shortage of PTC, many injured children continue to be treated at adult trauma centers (ATC). As a result, a growing controversy has evolved regarding the impact of PTC and ATC on outcome for injured children. METHODS: A retrospective analysis of 13,351 injured children entered in the Pennsylvania Trauma Outcome Study between 1993 and 1997 was conducted. Patients were stratified according to mechanism of injury, injury severity, specific organ injury, and type of trauma center: PTC; Level I ATC (ATC I); Level II ATC (ATC II); or ATC with added qualifications to treat children (ATC AQ). Mortality was the major outcome variable measured. RESULTS: Most injured children were treated at a PTC or ATC AQ. The majority of children below 10 years of age were admitted to PTC. Patients treated at PTC and ATC had similar injury severity as determined by median Injury Severity Score, mean Revised Trauma Score, and Glasgow Coma Scale. Overall survival was significantly better at PTC and ATC AQ compared with ATC I and ATC II. Survival for head, spleen, and liver injuries was significantly better at PTC compared with ATC AQ, ATC I, or ATC II. Children who sustained moderate or severe head injuries were more likely to undergo neurosurgical intervention and have a better outcome when treated at a PTC. Despite similar mean Abbreviated Injury Scores for spleen and liver, significantly more children underwent surgical exploration (especially splenectomy) for spleen and liver injuries at ATC compared with PTC. CONCLUSION: Children treated at PTC or ATC AQ have significantly better outcome compared with those treated at ATC. Severely injured children (Injury Severity Score > 15) with head, spleen, or liver injuries had the best overall outcome when treated at PTC. This difference in outcome may be attributable to the approach to operative and nonoperative management of head, liver, and spleen injuries at PTC.

Transcellular transport is not required for transmucosal bacterial passage across the intestinal membrane ex vivo.

The mechanisms underlying the process of bacterial translocation are poorly defined. Possible routes for transmucosal passage of bacteria include transcellular and paracellular channels. Bacterial engulfment is a prerequisite for transcellular transport. To determine whether transcellular transport is required for transmucosal bacterial passage, we examined the effect of various inhibitors of endocytosis, such as colchicine, cytochalasin B, and sodium fluoride on transmucosal passage of bacteria across an ileal mucosal membrane mounted in the Ussing chamber. Colchicine and sodium fluoride increased the rate of decline of the potential difference across the membranes. However, neither colchicine, cytochalasin B, nor sodium fluoride affected the incidence of transmucosal bacterial passage. Sodium fluoride, which depletes intracellular ATP, significantly decreased the number of bacteria that passed per membrane. Our data suggest that transcellular transport may not be required for spontaneous transmucosal passage of bacteria, and furthermore bacterial passage may be, at least in part, an energy-dependent process.

Management of blunt pancreatic injury in children.

BACKGROUND AND METHODS: Controversy persists regarding the management of pancreatic transection. Over the past 10 years, 51 patients admitted to the Children's Hospital of Pittsburgh sustained blunt pancreatic injuries. We reviewed their medical records to clarify the optimal management strategy and to define distinguishing characteristics, if any, of patients with pancreatic transection. RESULTS: Patients who sustained pancreatic transection had a significantly higher Injury Severity Score, length of stay, serum amylase, and serum lipase, than those patients who sustained pancreatic contusion. Patients who underwent laparotomy within 48 hours of injury for pancreatic transection had a significantly shorter length of stay than those who underwent laparotomy more than 48 hours after injury. CONCLUSION: Serum amylase greater than 200 and serum lipase greater than 1,800 may be useful clinical markers for major pancreatic ductal injury when combined with physical examination. Early operative intervention for pancreatic transection results in shorter length of stay and fewer complications.

Mortality among chemical plant workers exposed to acrylonitrile and other substances.

OBJECTIVES: To examine the association between exposure to acrylonitrile (AN) and cancer mortality by performing an independent and extended historical cohort study of workers from a chemical plant in Lima, Ohio included in a recent NCI-NIOSH study. METHODS: Subjects were 992 white males who were employed for three or more months between 1960 and 1996. We identified 110 deaths and cause of death for 108. Worker exposures were estimated quantitatively for AN and qualitatively for nitrogen products. Statistical analyses included U.S. and local county-based SMRs and internal relative risk regression of internal cohort rates. RESULTS: No statistically significant excess mortality risks were observed among the total cohort for the cancer sites implicated in previous studies: stomach, lung, breast, prostate, brain, and hematopoietic system. We observed a statistically significant bladder cancer excess based on four deaths (SMR=7.01, 95% CI=1.91-17.96) among workers not exposed to AN. Among 518 AN-exposed workers, we observed a not statistically significant excess of lung cancer based on external (SMR=1.32, 95% CI=.60-2.51) and internal (RR=1.98, 95% CI=.60-6.90) comparisons. Although the trends were not statistically significant, exposure-response analyses of internal cohort rates showed monotonically increasing lung cancer rate ratios with increasing AN exposure, with RRs exceeding 2.0 in the highest exposure categories. CONCLUSIONS: With the possible exception of lung cancer, this study provides little evidence that exposure to AN at levels experienced by Lima plant workers is associated with an increased risk of death from any cause including the implicated cancer sites.

Mortality patterns among workers exposed to acrylamide: 1994 follow up.

OBJECTIVE: To update the mortality experience of a cohort of 8508 workers with potential exposure to acrylamide at three plants in the United States from 1984-94. METHODS: Analyses of standardised mortality ratios (SMR) with national and local rates and relative risk (RR) regression modelling were performed to assess site specific cancer risks by demographic and work history factors, and exposure indicators for acrylamide and muriatic acid. RESULTS: For the 1925-94 study period, excess and deficit overall mortality risks were found for cancer sites of interest: brain and other central nervous system (CNS) (SMR 0.65, 95% confidence interval (95% CI) 0.36 to 1.09), thyroid gland (SMR 2.11, 95% CI 0.44 to 6.17), testis and other male genital organs (SMR 0.28, 95% CI 0.01 to 1.59), and cancer of the respiratory system (SMR 1.10, 95% CI 0.99 to 1.22); however, none was significant or associated with exposure to acrylamide. A previously reported excess mortality risk of cancer of the respiratory system at one plant remained increased among workers with potential exposure to muriatic acid (RR 1.50, 95% CI 0.86 to 2.59), but was only slightly increased among workers exposed or unexposed to acrylamide. In an exploratory exposure-response analysis of rectal, oesophageal, pancreatic, and kidney cancer, we found increased SMRs for some categories of exposure to acrylamide, but little evidence of an exposure-response relation. A significant 2.26-fold risk (95% CI 1.03 to 4.29) was found for pancreatic cancer among workers with cumulative exposure to acrylamide > 0.30 mg/m3.years; however, no consistent exposure-response relations were detected with the exposure measures considered when RR regression models were adjusted for time since first exposure to acrylamide. CONCLUSION: The contribution of 1115 additional deaths and nearly 60,000 person-years over the 11 year follow up period corroborate the original cohort study findings of little evidence for a causal relation between exposure to acrylamide and mortality from any cancer sites, including those of initial interest. This is the most definitive study of the human carcinogenic potential of exposure to acrylamide conducted to date.

Identification and case management in an HMO of patients at risk of preterm labor.

We carried out a study of pregnant patients in a health maintenance organization to identify and provide case management of women at risk of preterm labor and to determine important risk factors for preterm labor in a managed care population. Data were collected on 794 women who completed an initial prenatal care visit at HealthAmerica of Pittsburgh between July 15, 1994, and March 31, 1995, and delivered at a local Pittsburgh hospital. The patients were assessed during an initial call to schedule their first prenatal visit and also at the 8- to 15-week and 24- to 28-week prenatal visits. Patients scoring 10 or higher on the risk assessment form were referred to a nurse case manager who provided education and support. Results of a logistic regression analysis suggest that the risk assessment tool was effective in identifying women at risk for preterm labor. "Physical/stressful work", as assessed by the patient, history of a prior preterm birth, and multiple gestation were all statistically significant predictors of preterm birth. Further research is needed to confirm the finding that physical or stressful work is a significant predictor of preterm births and to determine which aspects of the work may increase the patient's risk. This study was based on 8 months of data; however, additional program implementation is needed to evaluate fully the potential long-term benefits of the program.

A two-stage protocol for verifying vital status in large historical cohort studies.

When access to the Social Security Administration's Master Death Claim File was restricted in the mid-1980s, researchers were left with no time- and cost-effective protocol for verifying the vital status of large historical cohorts. A two-stage tracing protocol was designed to overcome this restriction. Stage I relies on national-scale sources to focus on the complete and accurate identification of deaths among persons unconfirmed as alive and assumes that persons not identified as deceased are alive. Stage II tests the "alive" assumption by extensively tracing a random sample of cohort members with unconfirmed vital status. Stage II provides unbiased estimates of the proportion of deaths among the assumed "alives" in the cohort (misclassification rate) and the proportion of persons untraceable in the total cohort. This paper describes our two-stage protocol and an application to a large, ongoing occupational cohort study.