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Jeffrey S Young

Publications and source records attributed to Jeffrey S Young.

9 recordsLinked to original sources

Comparing resident measurements to attending surgeon self-perceptions of surgical educators.

OBJECTIVE: The purpose of this study was to evaluate the initiation and utility of evaluating attending surgeons as educators by resident trainees. Additionally, we were interested in comparing resident measurements to attending self-perceptions. METHODS: A written evaluation form, (utilizing five-point ordinal scale assignments) queried respondents regarding the performance of surgical attendings in the operating room, and other clinical settings. A similar form was distributed to the faculty members, which they used to evaluate themselves. Mean scores were determined, as were comparisons between self-perception and resident assessments. Differences in scores with p values less than 0.05 were considered statistically significant. RESULTS: Thirty-six residents evaluated 23 attendings. Mean assignments by residents of performance in the operating room, other clinical settings, and overall scores for all faculty members as a group were 4.22 +/- 0.04, 4.11 +/- 0.03, and 4.16 +/- 0.03, respectively, with a score of five, generally corresponding to a most favorable rating. When overall scores were analyzed, 10 attendings received scores that differed significantly from those received by their peers, with half of subjects above, and the other half being below the 95% confidence interval. Eighteen (78%) of attendings completed the self-evaluation forms, and of these, 11 (61%) had self-perceptions that differed significantly from overall scores as reported by the residents. CONCLUSIONS: Our evaluation process delineated significant differences among attending faculty members and identified individual strengths and weaknesses. Many educators' self-perceptions differed significantly from resident assessments, and attendings who did not evaluate themselves scored lower than their peers.

General Surgery↗

Differential local and systemic tumor necrosis factor-alpha responses to a second hit of lipopolysaccharide after hemorrhagic shock.

BACKGROUND: The immune response to subsequent stressors after traumatic hemorrhage and resuscitation (HR) may be dependent on timing and counterinflammatory cytokine expression. Our hypothesis was that the timing of the second hit would influence the immune response, and we investigated whether an early second stimulus after HR would result in worse acute lung injury. METHODS: One hour after HR or sham shock (Sham), mice were given intraperitoneal (IP) injections of lipopolysaccharide (LPS) or saline (Sal). Mortality, pulmonary function (PF), bronchoalveolar lavage neutrophil infiltration, and bronchoalveolar lavage (BAL), in addition to serum interleukin (IL)-10, IL-6, and tumor necrosis factor-alpha (TNF-alpha), were assessed. RESULTS: HR blunted serum TNF-alpha expression to LPS (HR+LPS, 424.8 pg/mL; Sham+LPS, 2,248.8 pg/mL; p < 0.05), but primed for increased bronchoalveolar lavage TNF-alpha (HR+LPS, 259.5 pg/mL; Sham+LPS, 23.5 pg/mL; p < 0.05). Elevated serum TNF-alpha corresponded with greater bronchoalveolar lavage neutrophil infiltration (HR+LPS, 0.93%; Sham+LPS, 17.5%; p < 0.05). IL-10 expression was similar in HR and Sham. There were no significant differences in mortality or PF between HR+LPS and Sham+LPS. CONCLUSION: Priming and blunting of the LPS-induced TNF-alpha response occurred concomitantly in two-hit mice, corresponding to an altered pattern of pulmonary inflammation, but no change in PF.

Animals↗

Stop the pendulum.

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Abdominal Injuries↗

Improved resuscitation minimizes respiratory dysfunction and blunts interleukin-6 and nuclear factor-kappa B activation after traumatic hemorrhage.

OBJECTIVE: We hypothesized that modifying resuscitation would alter hemorrhagic shock-induced respiratory dysfunction and correlate with nuclear factor-kappa B and cytokine expression. DESIGN: Randomized, controlled, prospective study. SETTING: University hospital trauma research laboratory. SUBJECTS: Female, Swiss Webster mice, 8-12 wks old. INTERVENTIONS: Hemorrhagic shock was induced by removing 0.025 mL of blood/g of body weight via a carotid catheter. Animals were resuscitated 30 mins later. Mice were randomized into four groups: group I was cannulated but not bled (sham); group II received normal saline to three times their shed blood volume; group III received their shed blood; and group IV received shed blood + normal saline at two times shed blood volume. MEASUREMENTS AND MAIN RESULTS: We measured the following: serum lactates at the end of shock and after resuscitation, pulmonary function before any instrumentation and after 24 hrs, cytokine concentrations by enzyme-linked immunosorbent assay, and nuclear factor-kappa B activity by electrophoretic mobility shift assay. Groups that were hemorrhaged had significant hypotension and a significant increase in serum lactates over 30 mins. Resuscitation returned the blood pressure to baseline in all groups, and lactates improved in all groups except group II. Group II also demonstrated a significant decrease in pulmonary function characterized by increased airway resistance and decreases in minute volume, lung compliance, and alveolar function. Bronchoalveolar fluid and serum interleukin-6 and whole lung nuclear factor-kappa B activity also were elevated significantly in group II. CONCLUSIONS: Group II demonstrated the least improvement in serum lactate after resuscitation, the most significant acute lung injury, and the greatest interleukin-6 and nuclear factor-kappa B response. Group IV mice had the least acute lung injury, with no detectable interleukin-6 response. Improved resuscitation with crystalloid and shed blood minimized acute lung injury. The reduction in pulmonary dysfunction after improved resuscitation may be attributable to a blunting of the nuclear factor-kappa B and interleukin-6 responses to hemorrhage.

Airway Resistance↗

The use of polynomial neural networks for mortality prediction in uncontrolled venous and arterial hemorrhage.

BACKGROUND: The ability to rapidly and accurately triage, evacuate, and utilize appropriate interventions can be problematic in the early decision-making process of trauma care. With current methods of prehospital data collection and analysis, decisions are often based upon single data points. This information may be insufficient for reliable decision-making. To date, no studies have attempted to utilize data at multiple time points for purposes of enhancing prediction, nor have studies attempted to synthesize prediction models with data reflecting both large-vessel venous and arterial injuries. Therefore, we performed a retrospective study to examine the potential utility of dynamic neural networks in predicting mortality using highly discretized uncontrolled hemorrhagic shock data. METHODS: One hundred forty-three swine with either grade V liver injuries or 2.8-mm aortotomies had hemodynamic data collected every minute throughout injury and resuscitation. The independent variables used as inputs to the polynomial neural networks (PNNs) included systolic blood pressure and mean arterial pressure (MAP). These inputs were used to predict mortality in individual swine 1 hour after injury using data up to 20 minutes after injury. Survival models were compared based on discrimination power (DP), i.e., where specificity equals sensitivity, and area under the receiver operating characteristic (ROC) curve (c-statistic). The Hosmer-Lemeshow (H-L) statistic was used to measure model calibration. RESULTS: The best PNN model predicted mortality at 60 minutes utilizing data from injury to 20 minutes after injury. This model produced a ROC area of 0.919, a DP of 0.857, and a H-L value of 16.47. A DP of 0.857 means that 85.7% of the survivors are correctly predicted to survive, and 85.7% of the nonsurvivors are predicted to die. MAP of survivors and nonsurvivors were graphed for comparative purposes. As this graph illustrates, the use of MAP alone cannot discriminate survivors from nonsurvivors. CONCLUSION: This study demonstrates that PNN models can effectively harness the dynamic nature of uncontrolled hemorrhagic shock data, despite utilizing data from large-vessel arterial and venous injuries. Utilizing the dynamic nature of hemorrhagic shock data in PNNs may ultimately allow the development of novel decision assist devices.

Animals↗

Adenosine A2A analogue improves neurologic outcome after spinal cord trauma in the rabbit.

BACKGROUND: ATL-146e, an adenosine A2A agonist, reduces paralysis after spinal cord ischemia-reperfusion. We hypothesized that systemic ATL-146e could improve neurologic outcome after blunt spinal cord trauma. METHODS: Twenty rabbits survived a thoracic spinal cord impact of 30 g-cm. One group received 0.06 microg/kg/min ATL-146e for the first 3 hours after impact (A2A group), whereas a second group received saline carrier (T/C group). Neurologic outcome was measured using the Tarlov scale (0-5). Histologic sections from the A2A and T/C groups were compared for neuronal viability. RESULTS: There was significant improvement in Tarlov scores of A2A animals compared with T/C animals at 12 hours (p = 0.007), with a trend toward improvement at 36 (p = 0.08) and 48 (p = 0.09) hours after injury. There was decreased neuronal attrition in A2A animals (p = 0.06). CONCLUSION: Systemic ATL-146e given after spinal cord trauma results in improved neurologic outcome. Adenosine A2A agonists may hold promise as a rapidly acting alternative to steroids in the early treatment of the spinal cord injured patient.

Animals↗

Blood transfusions correlate with infections in trauma patients in a dose-dependent manner.

Infections are a common and significant sequela of major traumatic injury. The objective of this study was to evaluate the relationship between infections in trauma patients and the transfusion of packed red blood cells (pRBCs) within the first 48 hours of admission. We hypothesized that transfusions of pRBCs were associated with an increased risk of infection in a dose-dependent manner. All adult patients admitted to the trauma service of a Level I trauma center from November 1996 to December 1999 were studied. Secondary analysis was performed on prospectively collected data. One thousand five hundred ninety-three consecutive patients were studied; of these 12.6 per cent developed at least one infection. The overall transfusion rate was 19.4 per cent. The infection rate in patients who received at least one transfusion was significantly higher (P < 0.0001) at 33.0 versus 7.6 per cent in patients receiving no pRBCs. Transfusions per patient ranged from 0 to 46 units. There was a clear exponential correlation in patients receiving between 0 and 15 transfusions (R2 = 0.757). Multivariate logistic regression, which was used to identify risk factors for the development of infection, demonstrated the odds ratio of receiving pRBCs to be 1.084, with a 95 per cent confidence interval of 1.028 to 1.142 (P = 0.0028). In summary there is a clear dose-dependent correlation between transfusions of pRBCs and the development of infection in trauma patients. Multivariate analysis further demonstrated that pRBCs were an independent risk factor for the development of infections. Although transfusions are frequently indicated, they should be administered appropriately and with no more pRBCs than absolutely necessary.

Adult↗

Young versus old: factors affecting mortality after blunt traumatic injury.

Advanced age predicts poor outcome after trauma. We have previously demonstrated that prolonged occult hypoperfusion (POH), defined as serum lactic acid >2.4 mmol/L persisting for >12 hours, is also associated with worse outcomes. We hypothesized that older patients--a group with potentially less physiologic reserve--would be at greater risk from POH. Prospective data from adult blunt trauma patients admitted to a surgical/trauma intensive care unit from January 1, 1998 through December 31, 1999 were analyzed. Mortality, POH, Injury Severity Score (ISS), chronic health designation (CH) from the Acute Physiology and Chronic Health Evaluation, emergency department Glasgow Coma Scale score (EDGCS), emergency department systolic blood pressure (EDSBP), and gender were compared between older (>55 years) and younger (<56 years) patients and then between nonsurvivors and survivors within age cohorts. Two hundred sixty-four patients were analyzed: 195 younger and 69 older. Mortality was 8.3 per cent (22/264). Older patients had higher mortality (20.3% vs 4.1%, P < 0.05), higher CH (42.9% +/- 1.3 vs 8.4% +/- 0.6), lower ISS (22.6 +/- 1.5 vs 25.6 +/- 0.8, P < 0.05), higher EDGCS (12.9 +/- 0.5 vs 10.7 +/- 0.4, P < 0.05), and higher EDSBP (141.5 +/- 4.1 vs 129.3 +/- 2.2). There were no differences in incidence of POH and gender. Within both age cohorts nonsurvivors had higher ISS, lower EDGCS, and higher CH. Older patients with POH had 34.6 per cent mortality as compared with 11.6 per cent for no POH (P < 0.05). Mortality in younger patients was no different in the presence of POH, and all non-survivors were male. Despite lower ISS and higher EDGCS and EDSBP older patients had five times the mortality of younger patients. Age-specific mortality was influenced by POH and gender. POH was associated with higher mortality only in older patients. With less physiologic reserve older patients may not have been able to adequately compensate for POH; this emphasizes the importance of rapidly correcting serum lactic acid as an endpoint in resuscitation in this population.

Adolescent↗