27 results on '"Villegas CV"'
Search Results
2. Should the IDC-9 Trauma Mortality Prediction Model become the new paradigm for benchmarking trauma outcomes?
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Haider AH, Villegas CV, Saleem T, Efron DT, Stevens KA, Oyetunji TA, Cornwell EE 3rd, Bowman S, Haack S, Baker SP, Schneider EB, Haider, Adil H, Villegas, Cassandra V, Saleem, Taimur, Efron, David T, Stevens, Kent A, Oyetunji, Tolulope A, Cornwell, Edward E 3rd, Bowman, Stephen, and Haack, Sara
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- 2012
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3. Operative Trauma and Mortality: The Role of Volume.
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Hatfield SA, Medina S, Gorman E, Barie PS, Winchell RJ, and Villegas CV
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- Humans, Male, Female, Middle Aged, Adult, Wounds and Injuries mortality, Wounds and Injuries surgery, Aged, Retrospective Studies, United States epidemiology, Hospitals, Low-Volume statistics & numerical data, Hemorrhage mortality, Databases, Factual statistics & numerical data, Young Adult, Hospital Mortality, Trauma Centers statistics & numerical data, Hospitals, High-Volume statistics & numerical data
- Abstract
Introduction: Operative volume is associated with improved outcomes across many surgical specialties, but this relationship has not been illustrated clearly in trauma. This study sought to evaluate the relationship between operative trauma volume and mortality, hypothesizing that increased volume would be associated with improved survival., Materials and Methods: The National Trauma Data Bank was queried for patients ≥18 y undergoing hemorrhage control surgery at level I or II trauma centers from 2017 to 2020. Hierarchical logistic regression was performed to evaluate the association between operative volume and in-hospital mortality, controlling for demographic and clinical characteristics., Results: 55,469 patients were included and treated at 516 centers. After adjustment, the operative volume was significantly associated with reduced mortality (OR 0.999, 95% CI 0.997-0.999, P = 0.018). However, there was considerable variability in volumes, with the busiest 5% of centers performing 90-294 operations per year, compared to 7-35 in the middle 50% of centers. To evaluate whether volume exhibited a uniform effect, the top 5% of trauma centers were excluded on subset analysis, with operative volume becoming nonsignificant in the remaining 491 centers (OR 0.999, 95% CI 0.996-1.001, P = 0.274)., Conclusions: Higher operative trauma volume is associated with reduced mortality for patients undergoing hemorrhage control surgery, but this mortality benefit appears to arise solely from very high-volume centers. The time-sensitive nature of hemorrhage control surgery makes centralization at this level impractical. Future efforts should focus on investigating the relationship between patient proximity to trauma centers and center volume as well as identifying modifiable factors common to high-volume centers that may be widely implemented., (Copyright © 2024 Elsevier Inc. All rights reserved.)
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- 2024
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4. Acute kidney injury in the acute care surgery patient: What you need to know.
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Villegas CV, Gorman E, Liu FM, and Winchell RJ
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Abstract: Acute kidney injury is associated with poor outcomes in the trauma and emergency general surgery population, and recent consensus definitions have allowed for significant advances in defining the burden of disease. The current definitions rely on overall functional measures (i.e., serum creatinine and urine output), which can be confounded by a variety of clinical factors. Biomarkers are increasingly being investigated as more direct diagnostic assays for the diagnosis of acute kidney injury and may allow earlier detection and more timely therapeutic intervention. Etiologies fall into two general categories: disorders of renal perfusion and exposure to nephrotoxic agents. Therapy is largely supportive, and prevention offers the best chance to decrease clinical impact., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2024
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5. A decade of firearm injuries: Have we improved?
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Hatfield SA, Medina S, Gorman E, Barie PS, Winchell RJ, and Villegas CV
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- Humans, Retrospective Studies, Male, United States epidemiology, Female, Adult, Middle Aged, COVID-19 epidemiology, COVID-19 mortality, Young Adult, Adolescent, Firearms statistics & numerical data, Aged, Wounds, Gunshot epidemiology, Wounds, Gunshot mortality, Trauma Centers statistics & numerical data
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Background: Firearm injuries are a growing public health issue, with marked increases coinciding with the coronavirus disease 2019 (COVID-19) pandemic. This study evaluates temporal trends over the past decade, hypothesizing that despite a growing number of injuries, mortality would be unaffected. In addition, the study characterizes the types of centers affected disproportionately by the reported firearm injury surge in 2020., Methods: Patients 18 years and older with firearm injuries from 2011 to 2020 were identified retrospectively using the National Trauma Data Bank (NTDB®). Trauma centers not operating for the entirety of the study period were excluded to allow for temporal comparisons. Joinpoint regression and risk-standardized mortality ratios (SMR) were used to evaluate injury counts and adjusted mortality over time. Subgroup analysis was performed to describe centers with the largest increases in firearm injuries in 2020., Results: A total of 238,674 patients, treated at 420 unique trauma centers, met inclusion criteria. Firearm injuries increased by 31.1% in 2020, compared to an annual percent change of 2.4% from 2011 to 2019 ( p = 0.01). Subset analysis of centers with the largest changes in firearm injuries in 2020 found that they were more often Level I centers, with higher historic trauma volumes and percentages of firearm injuries ( p < 0.001). Unadjusted mortality decreased by 0.9% from 2011 to 2020, but after controlling for demographics, injury characteristics and physiology, there was no difference in adjusted mortality over the same time period. However, among patients with injury severity scores ≥25, adjusted mortality improved compared with 2011 (SMR of 0.950 in 2020; 95% confidence interval, 0.916-0.986)., Conclusion: Firearm injuries pose an increasing burden to trauma systems, with Level I and high-volume centers seeing the largest growth in 2020. Despite increasing numbers of firearm injuries, mortality has remained unchanged over the past decade., Level of Evidence: Prognostic and Epidemiological; Level III., (Copyright © 2024 American Association for the Surgery of Trauma.)
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- 2024
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6. Rotational thromboelastometry in patients with acute respiratory distress syndrome owing to coronavirus disease 2019: Is there a viscoelastic fingerprint and a role for predicting thrombosis?
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Vasovic LV, Littlejohn J, Alqunaibit D, Dillard A, Qiu Y, Rand S, Bronstein M, Gibson CJ, Kelly AG, Lee C, Minneman JA, Narayan M, Shou J, Smith KE, Villegas CV, Winchell RJ, Cushing MM, and Barie PS
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- Humans, Thrombelastography, COVID-19 complications, COVID-19 diagnosis, Respiratory Distress Syndrome, Thrombophilia diagnosis, Thrombophilia etiology, Thrombosis diagnosis, Thrombosis etiology
- Abstract
Objectives: We evaluated rotational thromboelastometry tracings in 44 critically ill coronavirus disease 2019 patients, to determine whether there is a viscoelastic fingerprint and to test the hypothesis that the diagnosis and prediction of venous thromboembolism would be enhanced by the addition of rotational thromboelastometry testing., Results: Rotational thromboelastometry values reflected an increase in clot strength for the EXTEM, INTEM, and FIBTEM assays beyond the reference range. No hyperfibrinolysis was noted. Fibrinolysis shutdown was present but did not correlate with thrombosis; 32% (14/44) of patients experienced a thrombotic episode. For every 1 mm increase of FIBTEM maximum clot formation, the odds of developing thrombosis increased 20% (95% confidence interval, 0-40%, P = .043), whereas for every 1,000 ng/mL increase in D-dimer, the odds of thrombosis increased by 70% (95% confidence interval, 20%-150%, P = .004), after adjustment for age and sex (AUC 0.96, 95% confidence interval, 0.90-1.00). There was a slight but significant improvement in model performance after adding FIBTEM maximum clot formation and EXTEM clot formation time to D-dimer in a multivariable model (P = .04)., Conclusions: D-dimer concentrations were more predictive of thrombosis in our patient population than any other parameter. Rotational thromboelastometry confirmed the hypercoagulable state of coronavirus disease 2019 intensive care unit patients. FIBTEM maximum clot formation and EXTEM clot formation time increased the predictability for thrombosis compared with only using D-dimer. Rotational thromboelastometry analysis is most useful in augmenting the information provided by the D-dimer concentration for venous thromboembolism risk assessment when the D-dimer concentration is between 1,625 and 6,900 ng/dL, but the enhancement is modest. Fibrinolysis shutdown did not correlate with thrombosis., (Copyright © 2021 Elsevier Inc. All rights reserved.)
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- 2022
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7. Burns and Fatal Acute Lung Injury Ignited by a Smartphone Charger during Non-Invasive Ventilation for COVID-19.
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Shah SL, Barie PS, Bronstein ME, Chang PH, Gibson CJ, Houng AP, Kelly AE, Lee C, Lodescar RJ, Mahadev S, Shou J, Smith KE, Villegas CV, Winchell RJ, and Narayan M
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- Humans, Respiration, Artificial, SARS-CoV-2, Smartphone, Acute Lung Injury etiology, Burns, COVID-19, Noninvasive Ventilation
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- 2021
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8. Probative Value of the D-Dimer Assay for Diagnosis of Deep Venous Thrombosis in the Coronavirus Disease 2019 Syndrome.
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Gibson CJ, Alqunaibit D, Smith KE, Bronstein M, Eachempati SR, Kelly AG, Lee C, Minneman JA, Narayan M, Shou J, Villegas CV, Winchell RJ, and Barie PS
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- Academic Medical Centers, Anticoagulants therapeutic use, Biomarkers, Blood Coagulation Tests, Female, Humans, Inflammation Mediators metabolism, Intensive Care Units, Intubation, Intratracheal statistics & numerical data, Male, Prospective Studies, Venous Thrombosis drug therapy, COVID-19 complications, Fibrin Fibrinogen Degradation Products biosynthesis, Venous Thrombosis diagnosis, Venous Thrombosis etiology
- Abstract
Objectives: To describe the predictive utility of the D-dimer assay among patients with the coronavirus disease 2019 syndrome for unprovoked lower extremity deep venous thrombosis., Design: Prospective observational study with retrospective data analysis., Setting: Academic medical center surgical ICU., Patients: Seventy-two intubated patients with critical illness from coronavirus disease 2019., Interventions: Therapeutic anticoagulation after imaging diagnosis of the first three deep venous thrombosis cases was confirmed; therapeutic anticoagulation as prophylaxis thereafter to all subsequent ICU admissions., Measurements and Main Results: Seventy-two patients with severe coronavirus disease 2019 were screened for deep venous thrombosis after ICU admission with 102 duplex ultrasound examinations, with 12 cases (16.7%) of lower extremity deep venous thrombosis identified. There were no differences between groups with respect to age, renal function, or biomarkers except for D-dimer (median, 12,858 ng/mL [interquartile range, 3,176-30,770 ng/mL] for lower extremity deep venous thrombosis vs 2,087 ng/mL [interquartile range, 638-3,735 ng/mL] for no evidence of deep venous thrombosis; p < 0.0001). Clinical screening tools (Wells score and Dutch Primary Care Rule) had no utility. The C-statistic for D-dimer concentration was 0.874 ± 0.065. At the model-predicted cutoff value of 3,000 ng/mL, sensitivity was 100%, specificity was 51.1%, positive predictive value was 21.8%, and negative predictive value was 100%., Conclusions: Lower extremity deep venous thrombosis is prevalent in coronavirus disease 2019 disease and can be present on ICU admission. Screening has been recommended in the context of the pro-inflammatory, hypercoagulable background milieu. D-dimer concentrations are elevated in nearly all coronavirus disease 2019 patients, and the test appears reliable for screening for lower extremity deep venous thrombosis at or above a concentration of 3,000 ng/mL (more than 13-fold above the normal range). Full anticoagulation is indicated if the diagnosis is confirmed, and therapeutic anticoagulation should be considered for prophylaxis, as all coronavirus disease 2019 patients are at increased risk.
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- 2020
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9. Stop the Bleed: Effective Training in Need of Improvement.
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Villegas CV, Gupta A, Liu S, Curren J, Rosenberg J, Barie PS, Winchell RJ, and Narayan M
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- Academic Performance statistics & numerical data, Accidents, Traffic, Adult, Education, Nonprofessional statistics & numerical data, Female, Humans, Male, Manikins, Mass Casualty Incidents, Middle Aged, Program Evaluation, Simulation Training statistics & numerical data, Time Factors, Young Adult, Education, Nonprofessional organization & administration, First Aid methods, Hemorrhage therapy, Hemostatic Techniques, Simulation Training organization & administration
- Abstract
Background: The "Stop the Bleed" (StB) campaign aims to educate laypersons on performing bleeding control techniques in any setting that requires hemorrhage control, such as motor vehicle crashes or mass casualty incidents. Participants undergo a didactic and practical session, the latter incorporating a mannequin. We hypothesized that participants would increase content knowledge after StB participation and that the training could be improved by a more life-like bleeding modification of the mannequin., Materials and Methods: From July 2017 to January 2018, hospital and community members from a major metropolitan area participated in StB training. Participants provided demographic data regarding prior emergency training and were asked pre- and post-test questions (five-point Likert scale) regarding their response to hemorrhage. Individuals also evaluated the mannequin on bleeding simulation. Scores were reported as means with standard deviation or medians with interquartile ranges (IQRs) with subset analysis stratified by experience., Results: Of 402 participants, 310 provided complete data. On the composite, pre-test self-assessment, participants had a median score of 24 of 30 points (IQR 16-30). Post-testing demonstrated a statistically significant increase with a median score of 29 (IQR 25-30, P < 0.05). Subset analysis by prior emergency training (n = 102) demonstrated that both those with prior emergency training and those with no prior emergency training had significant improvement. On evaluation of the mannequin, participants reported that a more realistic model would increase their confidence in technique. Both subgroups reported that training would be enhanced if the mannequins were more realistic., Conclusions: StB is an effective education program. Those without prior experience or training in hemorrhage cessation demonstrated the most improvement. Regardless of background, participants reported overwhelmingly that the training would be more effective if it were more realistic. Future work to design and develop cost-effective mannequins demonstrating pulsatile blood flow and cessation of hemorrhage could enable learners to actually "Stop the Bleed"., (Copyright © 2020. Published by Elsevier Inc.)
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- 2020
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10. General Surgery Residents' Perception of Feedback: We Can Do Better.
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Gupta A, Villegas CV, Watkins AC, Foglia C, Rucinski J, Winchell RJ, Barie PS, and Narayan M
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- Clinical Competence, Cross-Sectional Studies, Feedback, Humans, Perception, General Surgery education, Internship and Residency
- Abstract
Background: Feedback (FB) regarding perioperative care is essential in general surgery residents' (GSRs) training. We hypothesized that FB would be distributed unevenly across preoperative (PrO), intraoperative (IO), and postoperative (PO) continuum of the perioperative period. We aimed to compare results between university- and community-hospital settings planning to institute structured, formalized FB in a large health care system operating multiple surgery residency programs in departments that are linked strategically., Methods: Quantitative, cross-sectional, Likert scale anonymous surveys were distributed to all GSRs (categorical and preliminary; university: community 1:2). Twenty-five questions considered frequency and perceived quality of FB in PrO, IO, and PO settings. Data were tabulated using REDCap and analyzed in Microsoft Excel using the Mann-Whitney U test, with α = 0.05. Comparisons were made between university- and community-hospital settings, between junior (Post-Graduate Year (PGY) 1-3) and senior (PGY 4-5) GSRs, and by gender., Results: Among 115 GSRs surveyed, 83 (72%) responded. Whereas 93% reported receiving some FB within the past year, 46% reported receiving FB ≤ 20% of the time. A majority (58%) found FB to be helpful ≥ 80% of the time. Among GSRs, 77%, 24%, and 64% reported receiving PrO, IO, or PO FB ≤ 20% of the time, respectively, but 52% also believed that FB was lacking in all 3 areas. Most GSRs wanted designated time for PrO planning FB (82%) and PO FB (87%), respectively. Thirty-six percent of GSRs reported that senior/chief (i.e., PGY-4/PGY-5 GSRs) took them through cases ≥40% of the time; notably,78% reported that FB from senior/chief GSRs was equally or more valuable than FB from attending surgeons. A majority (78%) reported that attending surgeons stated explicitly when they were providing FB only ≤20% of the time. GSRs at the community hospital campuses reported receiving a higher likelihood of "any" FB, IO FB, and PO FB (p < 0.05). Most GSRs surveyed preferred a structured format and designated times for debriefing and evaluation of performance. Subanalyses of gender and GSR level of training showed no differences., Conclusions: FB during GSR training varies across the perioperative continuum of care. Community programs seem to do better than University Programs. More work need to be done to elucidate why differences exist between the frequency of FB at University and Community programs. Further, data show particularly low FB outside of the operating room. Ideally, according to respondents, FB would be provided in a structured format and at designated times for debriefing and evaluation of performance, which poses a challenge considering the temporal dynamism of general surgery services., (Copyright © 2020 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.)
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- 2020
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11. Advancing the Education of Stop the Bleed: Development of a Perfused Synthetic Cadaver Model.
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Gupta A, Villegas CV, Rosenberg J, Winchell RJ, Barie PS, and Narayan M
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- Adult, Female, Humans, Male, Perfusion, Hemorrhage therapy, Hemostatic Techniques, Manikins, Simulation Training methods
- Abstract
Background: As active shootings and mass casualty incidents have become more prevalent, courses designed to teach basic hemorrhage control to laypersons have proliferated. Participants currently undergo Stop the Bleed (StB) training currently use a synthetic limb mannequin. In a prior survey of 88 participants, there was overwhelming sentiment that the mannequin was limited by its inability to demonstrate cessation of bleeding when hemorrhage control techniques were applied. We hypothesized that simulated bleeding that can be controlled by StB techniques would improve the mannequin and increase confidence of trainees in achieving bleeding control., Methods: The mannequin was redesigned to be a self-contained model mimicking bleeding, with fluid flowing from a reservoir into a latex tubing with a laceration mimicking an arterial wound. Fluid was pumped by a rubber bulb attached to the tubing and held in the instructor's hand. Twenty StB trainers conducted beta testing of the perfused mannequin. Forty participants underwent training with both old and new models and completed posttraining surveys., Results: Beta-testers reported positive feedback regarding both realism of the perfused mannequin and participants' ability to obtain bleeding control using StB techniques. Participants who trialed the mannequin reported increased awareness of the rate of blood flow out of a wound, which in turn increased their sense of urgency to achieve hemostasis., Conclusions: In an effort to address shortcomings noted by participants in the current StB mannequin, we developed a novel perfused bleeding mannequin, which responds appropriately to various hemorrhage cessation techniques and is both high fidelity and low cost., (Copyright © 2019 Elsevier Inc. All rights reserved.)
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- 2019
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12. BODIPY as electron withdrawing group for the activation of double bonds in asymmetric cycloaddition reactions.
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Guerrero-Corella A, Asenjo-Pascual J, Pawar TJ, Díaz-Tendero S, Martín-Sómer A, Gómez CV, Belmonte-Vázquez JL, Ramírez-Ornelas DE, Peña-Cabrera E, Fraile A, Cruz DC, and Alemán J
- Abstract
In this work we have found that a BODIPY can be used as an electron withdrawing group for the activation of double bonds in asymmetric catalysis. The synthesis of cyclohexyl derivatives containing a BODIPY unit can easily be achieved via trienamine catalysis. This allows a new different asymmetric synthesis of BODIPY derivatives and opens the door to future transformation of this useful fluorophore. In addition, the Quantum Chemistry calculations and mechanistic studies provide insights into the role of BODIPY as an EWG.
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- 2019
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13. Sequential treatment with thrombopoietin-receptor agonists (TPO-RAs) in immune thrombocytopenia (ITP): experience in our center.
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González KJ, Zuluaga SO, DaRos CV, Rodríguez PP, and Martí AC
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- Benzoates pharmacology, Female, Humans, Hydrazines pharmacology, Male, Middle Aged, Pyrazoles pharmacology, Recombinant Fusion Proteins pharmacology, Thrombopoietin pharmacology, Treatment Outcome, Benzoates therapeutic use, Hydrazines therapeutic use, Purpura, Thrombocytopenic, Idiopathic diagnosis, Purpura, Thrombocytopenic, Idiopathic drug therapy, Pyrazoles therapeutic use, Receptors, Fc therapeutic use, Receptors, Thrombopoietin agonists, Recombinant Fusion Proteins therapeutic use, Thrombopoietin therapeutic use
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- 2017
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14. The hazards of off-road motor sports: Are four wheels better than two?
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Villegas CV, Bowman SM, Zogg CK, Scott VK, Haut ER, Stevens KA, Efron DT, and Haider AH
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- Accidents, Traffic statistics & numerical data, Age Factors, Analysis of Variance, Humans, Injury Severity Score, Length of Stay statistics & numerical data, Retrospective Studies, Risk Factors, United States epidemiology, Wounds and Injuries epidemiology, Accident Prevention, Accidents, Traffic prevention & control, Hospitalization statistics & numerical data, Motorcycles, Off-Road Motor Vehicles statistics & numerical data, Protective Devices statistics & numerical data, Trauma Centers statistics & numerical data, Wounds and Injuries prevention & control
- Abstract
Background: Off-road motorsports are an increasing popular activity, yet the relative safety profile of all-terrain vehicles (ATV) to off-road motorcycles (ORMC) has not been compared., Study Design: A retrospective review of the 2002-2006 US National Trauma Data Bank of ATV and ORMC crash victims. Patients were described according to demographic (age, sex, race and ethnicity, insurance status) and injury characteristics (Injury Severity Score, hypotension, motor component of the Glasgow Coma Score, presence of a severe head or extremity injury) known to affect trauma outcomes. Logistic regression evaluated the independent effect of an ATV vehicle on mortality, intensive care unit (ICU) admission, and placement on a ventilator relative to ORMC. The anatomic distribution of severe injuries was compared between survivors and decedents within each vehicle type., Results: A total of 34,457 patients met inclusion criteria, of whom, 24,582 were ATV patients and 9875 were ORMC patients. ATV patients had 51% higher risk-adjusted odds of death (OR 1.51; 95% CI 1.03-2.20), 55% higher risk-adjusted odds of being admitted to an ICU (OR 1.55; 95% CI 1.42-1.70), and 42% higher risk-adjusted odds of being placed on a ventilator (OR 1.42, 95% CI 1.17-1.72) compared to ORMC crash victims. Decedents in both vehicle types were more likely to suffer severe head, thoracic, and abdominal injuries relative to their surviving counterparts., Conclusion: For injured riders, ATVs are associated with increased mortality and higher resource utilisation compared to ORMCs. Both groups suffer distinct anatomic injuries, suggesting the need for focused areas of injury prevention planning and research., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
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- 2016
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15. Organocatalytic cascade reactions: diversity-oriented synthesis for the construction of hydroisoquinoline scaffolds.
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Gómez CV, Cruz DC, Mose R, and Jørgensen KA
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- Catalysis, Crystallography, X-Ray, Isoquinolines chemistry, Molecular Structure, Stereoisomerism, Acrylamides chemistry, Aldehydes chemistry, Cycloaddition Reaction methods, Isoquinolines chemical synthesis
- Abstract
The organocatalytic enantioselective synthesis of highly functionalized hydroisoquinolines by trienamine-mediated [4+2]-cycloaddition/nucleophilic ring-closing reaction cascade sequence of cyanoacrylamides with 2,4-dienals is presented. The corresponding cycloadducts are formed in high yields and excellent stereoselectivities. Moreover, a series of transformations demonstrate the synthetic application of the obtained hydroisoquinolines.
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- 2014
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16. Association between intentional injury and long-term survival after trauma.
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Haider AH, Young JH, Kisat M, Villegas CV, Scott VK, Ladha KS, Haut ER, Cornwell EE, MacKenzie EJ, and Efron DT
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- Adolescent, Adult, Aged, Female, Follow-Up Studies, Humans, Kaplan-Meier Estimate, Male, Maryland epidemiology, Middle Aged, Prognosis, Proportional Hazards Models, Retrospective Studies, Socioeconomic Factors, Survival Rate trends, Trauma Severity Indices, Wounds and Injuries diagnosis, Wounds and Injuries therapy, Young Adult, Risk Assessment methods, Wounds and Injuries mortality
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Objective: To determine the risk-adjusted mortality of intentionally injured patients within 7 to 9 years postinjury, compared with unintentionally injured patients., Background: Violent injury contributes significantly to trauma mortality in the United States. Homicide is the second leading killer of American youth, aged 15 to 24 years. Long-term survival among intentionally injured patients has not been well studied. It is also unknown whether intentionally injured patients have worse long-term survival compared with unintentionally or accidentally injured patients with equivalent injuries., Methods: Adult trauma patients admitted for 24 hours or more and discharged alive from the Johns Hopkins Hospital from January 1, 1998, to December 31, 2000, were included. The primary outcome was mortality within 7 to 9 years postinjury. Long-term patient survival was determined using the National Death Index. The association between injury intentionality and mortality was investigated using a Cox proportional hazard regression model, adjusted for confounders such as injury severity and patient race, socioeconomic status, and comorbid conditions. Overall differences in survival between those with intentional versus unintentional injury were also determined by comparing adjusted Kaplan-Meier survival curves., Results: A total of 2062 patients met inclusion criteria. Of these, 56.4% were intentionally injured and 43.6% were unintentionally injured. Compared with unintentionally injured patients, intentionally injured patients were younger and more often male and from a zip code with low median household income. Approximately 15% of all patients had died within 7 to 9 years of follow-up. Older age and presence of comorbidities were associated with this outcome; however, intentional injury was not found to be significantly associated with long-term mortality rates. There was also no significant difference in survival curves between groups; intentionally injured patients were much more likely to die of a subsequent injury, whereas those with unintentional injury commonly died of noninjury causes., Conclusions: There was no significant difference in mortality between intentionally injured and unintentionally injured patients within 7 to 9 years postinjury. These results confirm the long-term effectiveness of lifesaving trauma care for those with intentional injury. However, given that patients with intentional injuries were more likely to suffer a subsequent violent death, interventions focused on breaking the cycle of violence are needed.
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- 2014
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17. The severity of disparity: increasing injury intensity accentuates disparate outcomes following trauma.
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Losonczy LI, Weygandt PL, Villegas CV, Hall EC, Schneider EB, Cooper LA, Cornwell EE 3rd, Haut ER, Efron DT, and Haider AH
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- Adolescent, Adult, Databases, Factual, Female, Humans, Male, Racial Groups statistics & numerical data, Retrospective Studies, United States epidemiology, Young Adult, Healthcare Disparities, Injury Severity Score, Medically Uninsured statistics & numerical data, Wounds and Injuries mortality
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Objective: Studies have shown disparities in mortality among racial groups and among those with differing insurance coverage. Our goal was to determine if injury severity affects these disparities., Methods: We classified patients from the 2003-2008 National Trauma Data Banks suffering moderate to severe injuries into six groups based on race/ethnicity and insurance, stratifying by injury severity. Logistic regression compared odds of death between races-ethnicities/insurance groups within these strata. We adjusted for age, gender, Injury Severity Score, Glasgow Coma Scale motor component, hypotension, and mechanism of injury., Results: Patients meeting inclusion criteria numbered 760,598. Disparities between races-ethnicities/insurance groups increased as injury severity worsened. Odds of death for uninsured Black patients compared with insured Whites increased from 1.82 among moderately injured patients to 3.14 among severely injured, hypotensive patients. A similar pattern was seen among uninsured Hispanic patients., Conclusions: Disparities in trauma mortality suffered by minority and uninsured patients, when compared with non-minority and insured patients, worsen with increasing injury.
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- 2014
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18. 1,4-Naphthoquinones in H-bond-directed trienamine-mediated strategies.
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Albrecht Ł, Gómez CV, Jacobsen CB, and Jørgensen KA
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- Hydrogen Bonding, Molecular Structure, Oxidation-Reduction, Stereoisomerism, Alkenes chemistry, Naphthoquinones chemical synthesis, Naphthoquinones chemistry
- Abstract
The synthesis of optically active, carboannulated dihydronaphthoquinone and naphthoquinone derivatives with up to four stereogenic centers is demonstrated by H-bond-directed, trienamine-mediated [4 + 2]-cycloadditions. The outcome of the reaction between 2,4-dienals and 1,4-naphthoquinones is controlled by the substituent in the 2-position of the 1,4-naphthoquinone. In the case of sterically demanding 2-substituted derivatives, dihydronaphthoquinones are obtained. However, when a hydrogen atom is present in the 2-position, a subsequent oxidation of the initially formed cycloadducts occurs yielding naphthoquinones.
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- 2013
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19. Predictors of sepsis in moderately severely injured patients: an analysis of the National Trauma Data Bank.
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Kisat M, Villegas CV, Onguti S, Zafar SN, Latif A, Efron DT, Haut ER, Schneider EB, Lipsett PA, Zafar H, and Haider AH
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- Accidental Falls, Accidents, Traffic, Adolescent, Adult, Black or African American, Aged, Aged, 80 and over, Databases, Factual, Female, Humans, Injury Severity Score, Logistic Models, Male, Middle Aged, Multivariate Analysis, Odds Ratio, Retrospective Studies, Risk Factors, Sepsis etiology, Socioeconomic Factors, United States epidemiology, Sepsis epidemiology, Wounds and Injuries epidemiology, Wounds and Injuries microbiology
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Background: Post-traumatic sepsis is a significant cause of in-hospital death. However, socio-demographic and clinical characteristics that may predict sepsis in injured patients are not well known. The objective of this study was to identify risk factors that may be associated with post-traumatic sepsis., Methods: Retrospective analysis of patients in the National Trauma Data Bank for 2007-2008. Patients older than 16 years of age with an Injury Severity Score (ISS) ≥ 9 points were included. Multivariable logistic regression was used to determine association of sepsis with patient (age, gender, ethnicity, and insurance status), injury (mechanism, ISS, injury type, hypotension), and clinical (major surgical procedure, intensive care unit admission) characteristics., Results: Of a total of 1.3 million patients, 373,370 met the study criteria, and 1.4% developed sepsis, with an associated mortality rate of approximately 20%. Age, male gender, African-American race, hypotension on emergency department presentation, and motor vehicle crash as the injury mechanism were independently associated with post-traumatic sepsis., Conclusions: Socio-demographic and injury factors, such as age, race, hypotension on admission, and severity and mechanism of injury predict post-traumatic sepsis significantly. Further exploration to explain why these patient groups are at increased risk is warranted in order to understand better and potentially prevent this life-threatening complication.
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- 2013
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20. Influence of the National Trauma Data Bank on the study of trauma outcomes: is it time to set research best practices to further enhance its impact?
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Haider AH, Saleem T, Leow JJ, Villegas CV, Kisat M, Schneider EB, Haut ER, Stevens KA, Cornwell EE 3rd, MacKenzie EJ, and Efron DT
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- Epidemiologic Research Design, Humans, Injury Severity Score, Length of Stay statistics & numerical data, Multivariate Analysis, Risk Adjustment methods, Risk Adjustment standards, Survival Rate, Treatment Outcome, Benchmarking standards, Databases, Factual, Registries standards, Wounds and Injuries mortality, Wounds and Injuries therapy
- Abstract
Background: Risk-adjusted analyses are critical in evaluating trauma outcomes. The National Trauma Data Bank (NTDB) is a statistically robust registry that allows such analyses; however, analytical techniques are not yet standardized. In this study, we examined peer-reviewed manuscripts published using NTDB data, with particular attention to characteristics strongly associated with trauma outcomes. Our objective was to determine if there are substantial variations in the methodology and quality of risk-adjusted analyses and therefore, whether development of best practices for risk-adjusted analyses is warranted., Study Design: A database of all studies using NTDB data published through December 2010 was created by searching PubMed and Embase. Studies with multivariate risk-adjusted analyses were examined for their central question, main outcomes measures, analytical techniques, covariates in adjusted analyses, and handling of missing data., Results: Of 286 NTDB publications, 122 performed a multivariable adjusted analysis. These studies focused on clinical outcomes (51 studies), public health policy or injury prevention (30), quality (16), disparities (15), trauma center designation (6), or scoring systems (4). Mortality was the main outcome in 98 of these studies. There were considerable differences in the covariates used for case adjustment. The 3 covariates most frequently controlled for were age (95%), Injury Severity Score (85%), and sex (78%). Up to 43% of studies did not control for the 5 basic covariates necessary to conduct a risk-adjusted analysis of trauma mortality. Less than 10% of studies used clustering to adjust for facility differences or imputation to handle missing data., Conclusions: There is significant variability in how risk-adjusted analyses using data from the NTDB are performed. Best practices are needed to further improve the quality of research from the NTDB., (Copyright © 2012 American College of Surgeons. Published by Elsevier Inc. All rights reserved.)
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- 2012
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21. Predictors of positive head CT scan and neurosurgical procedures after minor head trauma.
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Kisat M, Zafar SN, Latif A, Villegas CV, Efron DT, Stevens KA, Haut ER, Schneider EB, Zafar H, and Haider AH
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- Adolescent, Adult, Black or African American, Age Factors, Aged, Aged, 80 and over, Craniocerebral Trauma ethnology, Female, Humans, Logistic Models, Male, Middle Aged, Predictive Value of Tests, Retrospective Studies, Sex Factors, Treatment Outcome, White People, Young Adult, Craniocerebral Trauma diagnostic imaging, Craniocerebral Trauma surgery, Head diagnostic imaging, Neurosurgical Procedures, Tomography, X-Ray Computed, Trauma Severity Indices
- Abstract
Background: There continues to be an ongoing debate regarding the utility of head CT scans in patients with a normal Glasgow Coma Scale (GCS) after minor head injury. The objective of this study is to determine patient and injury characteristics that predict a positive head CT scan or need for a neurosurgical procedure (NSP) among patients with blunt head injury and a normal GCS., Materials and Methods: Retrospective analysis of adult patients in the National Trauma Data Bank who presented to the ED with a history of blunt head injury and a normal GCS of 15. The primary outcomes were a positive head CT scan or a NSP. Multivariate logistic regression controlling for patient and injury characteristics was used to determine predictors of each outcome., Results: Out of a total of 83,566 patients, 24,414 (29.2%) had a positive head CT scan and 3476 (4.2%) underwent a NSP. Older patients and patients with a history of fall (compared with a motor vehicle crash) were more likely to have a positive finding on a head CT scan. Male patients, African-Americans (compared with Caucasians), and those who presented with a fall were more likely to have a NSP., Conclusions: Older age, male gender, ethnicity, and mechanism of injury are significant predictors of a positive finding on head CT scans and the need for neurosurgical procedures. This study highlights patient and injury-specific characteristics that may help in identifying patients with supposedly minor head injury who will benefit from a head CT scan., (Copyright © 2012 Elsevier Inc. All rights reserved.)
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- 2012
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22. Outcome of selective non-operative management of penetrating abdominal injuries from the North American National Trauma Database.
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Zafar SN, Rushing A, Haut ER, Kisat MT, Villegas CV, Chi A, Stevens K, Efron DT, Zafar H, and Haider AH
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- Abdominal Injuries mortality, Adolescent, Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Treatment Failure, Wounds, Gunshot mortality, Wounds, Stab mortality, Young Adult, Abdominal Injuries therapy, Wounds, Gunshot therapy, Wounds, Stab therapy
- Abstract
Background: The aim of this study was to investigate trends in the practice of selective non-operative management (SNOM) for penetrating abdominal injury (PAI) and to determine factors associated with its failure., Methods: The National Trauma Data Bank for 2002-2008 was reviewed. Patients with PAI were categorized as those who underwent successful SNOM (operative management not required) and those who failed SNOM (surgery required more than 4 h after admission). Yearly rates of SNOM versus non-therapeutic laparotomy (NTL) were plotted. Multivariable regression analysis was performed to identify factors associated with failed SNOM and mortality., Results: A total of 12 707 patients with abdominal gunshot and 13 030 with stab wounds were identified. Rates of SNOM were 22.2 per cent for gunshot and 33.9 per cent for stab wounds, and increased with time (P < 0.001). There was a strong correlation between the rise in SNOM and the decline in NTL (r = - 0.70). SNOM failed in 20.8 and 15.2 per cent of patients with gunshot and stab wounds respectively. Factors predicting failure included the need for blood transfusion (odds ratio (OR) 1.96, 95 per cent confidence interval 1.11 to 3.46) and a higher injury score. Failed SNOM was independently associated with mortality in both the gunshot (OR 4.48, 2.07 to 9.70) and stab (OR 9.83, 3.44 to 28.00) wound groups., Conclusion: The practice of SNOM is increasing, with an associated decrease in the rate of NTL for PAI. In most instances SNOM is successful; however, its failure is associated with increased mortality. Careful patient selection and adherence to protocols designed to decrease the failure rate of SNOM are recommended., (Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.)
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- 2012
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23. Association of unconscious race and social class bias with vignette-based clinical assessments by medical students.
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Haider AH, Sexton J, Sriram N, Cooper LA, Efron DT, Swoboda S, Villegas CV, Haut ER, Bonds M, Pronovost PJ, Lipsett PA, Freischlag JA, and Cornwell EE 3rd
- Subjects
- Adult, Baltimore, Cross-Sectional Studies, Data Collection, Decision Making, Female, Humans, Internet, Male, Physician-Patient Relations, Physicians psychology, Schools, Medical, Young Adult, Black or African American, Black People, Prejudice, Social Class, Students, Medical psychology, Unconscious, Psychology, White People
- Abstract
Context: Studies involving physicians suggest that unconscious bias may be related to clinical decision making and may predict poor patient-physician interaction. The presence of unconscious race and social class bias and its association with clinical assessments or decision making among medical students is unknown., Objective: To estimate unconscious race and social class bias among first-year medical students and investigate its relationship with assessments made during clinical vignettes., Design, Setting, and Participants: A secure Web-based survey was administered to 211 medical students entering classes at Johns Hopkins School of Medicine, Baltimore, Maryland, in August 2009 and August 2010. The survey included the Implicit Association Test (IAT) to assess unconscious preferences, direct questions regarding students' explicit race and social class preferences, and 8 clinical assessment vignettes focused on pain assessment, informed consent, patient reliability, and patient trust. Adjusting for student demographics, multiple logistic regression was used to determine whether responses to the vignettes were associated with unconscious race or social class preferences., Main Outcome Measures: Association of scores on an established IAT for race and a novel IAT for social class with vignette responses., Results: Among the 202 students who completed the survey, IAT responses were consistent with an implicit preference toward white persons among 140 students (69%, 95% CI, 61%-75%). Responses were consistent with a preference toward those in the upper class among 174 students (86%, 95% CI, 80%-90%). Assessments generally did not vary by patient race or occupation, and multivariable analyses for all vignettes found no significant relationship between implicit biases and clinical assessments. Regression coefficient for the association between pain assessment and race IAT scores was -0.49 (95% CI, -1.00 to 0.03) and for social class, the coefficient was -0.04 (95% CI, -0.50 to 0.41). Adjusted odds ratios for other vignettes ranged from 0.69 to 3.03 per unit change in IAT score, but none were statistically significant. Analysis stratified by vignette patient race or class status yielded similarly negative results. Tests for interactions between patient race or class status and student IAT D scores in predicting clinical assessments were not statistically significant., Conclusions: The majority of first-year medical students at a single school had IAT scores consistent with implicit preference for white persons and possibly for those in the upper class. However, overall vignette-based clinical assessments were not associated with patient race or occupation, and no association existed between implicit preferences and the assessments.
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- 2011
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24. Mechanism of injury predicts case fatality and functional outcomes in pediatric trauma patients: the case for its use in trauma outcomes studies.
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Haider AH, Crompton JG, Oyetunji T, Risucci D, DiRusso S, Basdag H, Villegas CV, Syed ZU, Haut ER, and Efron DT
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- Accidental Falls statistics & numerical data, Accidents, Traffic statistics & numerical data, Adolescent, Child, Child, Preschool, Databases, Factual, Female, Humans, Injury Severity Score, Logistic Models, Male, Odds Ratio, Patient Discharge, Prognosis, Retrospective Studies, United States epidemiology, Wounds and Injuries epidemiology, Wounds, Gunshot epidemiology, Wounds, Gunshot mortality, Wounds and Injuries etiology, Wounds and Injuries mortality
- Abstract
Background/purpose: The mechanism of injury (MOI) may serve as a useful adjunct to injury scoring systems in pediatric trauma outcomes research. The objective is to determine the independent effect of MOI on case fatality and functional outcomes in pediatric trauma patients., Methods: Retrospective review of pediatric patients ages 2 to 18 years in the National Trauma Data Bank from 2002 through 2006 was done. Mechanism of injury was classified by the International Classification of Diseases, Ninth Revision, E codes. The main outcome measures were mortality, discharge disposition (home vs rehabilitation setting), and functional impairment at hospital discharge. Multiple logistic regression was used to adjust for injury severity (using the Injury Severity Score and the presence of shock upon admission in the emergency department), age, sex, and severe head or extremity injury., Results: Thirty-five thousand ninety-seven pediatric patients in the National Trauma Data Bank met inclusion criteria. Each MOI had differences in the adjusted odds of death or functional disabilities as compared with the reference group (fall). The MOI with the greatest risk of death was gunshot wounds (odds ratio [OR], 3.52; 95% confidence interval [CI], 2.23-5.54 95). Pediatric pedestrians struck by a motor vehicle have the highest risk of locomotion (OR, 3.30; 95% CI, 2.89-3.77) and expression (OR, 1.65; 95% CI, 1.22-2.23) disabilities., Conclusion: Mechanism of injury is a significant predictor of clinical and functional outcomes at discharge for equivalently injured patients. These findings have implications for injury prevention, staging, and prognosis of traumatic injury and posttreatment planning., (Copyright © 2011. Published by Elsevier Inc.)
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- 2011
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25. Global surgical package reimbursement and the acute care surgeon: a threat to optimal care.
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Schneider EB, Haider AH, Lidor AO, Efron JE, Villegas CV, Stevens KA, Hirani SA, Haut ER, and Efron DT
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- Age Factors, Aged, Colectomy methods, Colectomy mortality, Comorbidity, Emergency Treatment statistics & numerical data, Female, Hospital Mortality, Humans, Insurance, Health statistics & numerical data, Length of Stay statistics & numerical data, Male, Regression Analysis, Sex Factors, Statistics, Nonparametric, Colectomy economics, Emergency Treatment economics, Fees and Charges statistics & numerical data
- Abstract
Background: Emergency surgery patients risk greater mortality and morbidity than elective patients undergoing the same procedure. However, the differential effort required for the care of emergency surgical patients is poorly defined. This study sought to characterize costs and outcomes of elective versus emergent right hemicolectomy., Methods: 2006 Nationwide Inpatient Sample data were used to compare mortality, total charges, and length of stay (LOS) in patients undergoing emergency versus elective right hemicolectomy (International Classification of Diseases-9th procedure code 45.73). Mann-Whitney tests examined total costs and LOS; multivariable regression modeled inhospital mortality controlling for age, gender, insurance status, and comorbidities., Results: Among 8,074,825 inpatient admissions, 7,767 emergent and 10,399 elective right hemicolectomies were identified. Emergent patients were similar in age (66.9 years vs. 67.6 years; p=0.129), more likely women (43.7% vs. 42.3%; p=0.048) and had greater comorbidity (Charlson score 3.37 vs. 3.01; p<0.001) compared with elective patients. Emergent patient LOS was approximately double that of elective patients (13 days vs. 7 days; p<0.001). Mean total charges were $78,118 for emergent versus $39,265 elective patients (p<0.001). Emergent patients had greater odds of inhospital mortality (odds ratio, 5.86; 95% confidence intervals, 4.80-7.14)., Conclusions: Emergent right hemicolectomy patients have greater comorbidity, experience longer stays, accrue twice the charges, and have higher mortality risk. This reflects a heightened effort required to care for emergent patients unrecognized by Global Surgical Package reimbursement. The concentration of emergency surgical patients in acute care surgery services necessitates accounting for the additional effort associated with these predictable risks to ensure optimal care., (Copyright © 2011 by Lippincott Williams & Wilkins)
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- 2011
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26. Preparation of ex vivo-based biomaterials using convective flow decellularization.
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Montoya CV and McFetridge PS
- Subjects
- Elastic Modulus, Humans, Hydroxyproline metabolism, Permeability, Phospholipids isolation & purification, Proteins isolation & purification, Solubility, Tensile Strength, Tissue Scaffolds, Umbilical Veins ultrastructure, Biocompatible Materials chemical synthesis, Cell Separation methods, Convection, Tissue Engineering methods, Umbilical Veins cytology
- Abstract
With advantageous biomechanical properties, materials derived from ex vivo tissues are being actively investigated as scaffolds for tissue engineering applications. However, decellularization treatments are required before implantation to reduce the materials immune impact. The aim of these investigations was to assess a convective flow model as an enhanced methodology to decellularize ex vivo tissue. Isolated human umbilical veins were decellularized using two methods: rotary agitation at 100rpm on orbital shaker plates, and convective flow run at 5, 50, and 150mmHg within perfusion bioreactors. Extracted phospholipids and total soluble protein were assessed over time. Histology, SEM, and uniaxial tensile testing analysis were carried out to evaluate variation in the tissues. After 72h, samples exposed to traditional rotary agitation showed retention of whole cells and cellular components, whereas pressure-based systems showed no visual sign of cells. The convective flow method was significantly more effective at removing phospholipid and total protein than the agitation model. High transmembrane pressure (150mmHg) resulted in higher phospholipids extraction. However, a more efficient protein extraction occurred at 50mmHg. Variation in extraction rates was dependent on tissue permeability, which varied as pressure increased. Collectively, these findings show significant improvements in decellularization efficiency that may lead to more immune compliant ex vivo-derived biomaterials.
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- 2009
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27. Pituitary changes involved in prolactin secretion induced by mifepristone and naloxone during late pregnancy.
- Author
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Gabutti CV, Ezquer M, Deis R, Maldonado C, and Soaje M
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- Animals, Female, Pregnancy, RNA, Messenger drug effects, RNA, Messenger metabolism, Rats, Rats, Wistar, Time Factors, Lactotrophs drug effects, Lactotrophs ultrastructure, Mifepristone agonists, Naloxone agonists, Pituitary Gland drug effects, Pituitary Gland ultrastructure, Prolactin drug effects, Prolactin metabolism
- Abstract
Background/aims: The antiprogesterone mifepristone facilitates prolactin release, an effect enhanced by administration of the opioid antagonist naloxone. The present study explores ultrastructural changes in lactotropes after mifepristone and naloxone administration, correlating them with the expression of pituitary prolactin., Methods/results: Rats were sacrificed at 18:00 h on day 19 of pregnancy. Prolactin immunoelectron microscopy of lactotropes from control rats showed characteristics of quiescent cells with numerous small and spherical secretory granules. Naloxone administration did not modify lactotrope morphology or prolactin expression in terms of mRNA or protein abundances. Mifepristone treatment induced lactotrope activation with development of the rough endoplasmic reticulum and Golgi complex with prolactin immunoreactive small newly formed and large mature secretory granules. Mifepristone increased prolactin mRNA and protein expression. Naloxone administration to mifepristone-treated rats potentiated lactotrope activation compared with mifepristone alone showing exocytotic images of prolactin granules and some cells with evident signs of involution., Conclusions: (1) Blockade of progesterone action by mifepristone activated the lactotrope, increased significantly prolactin mRNA and protein expression and prepared the pituitary for naloxone action. (2) The high serum prolactin levels induced by mifepristone and naloxone may regulate negatively lactotrope activity as suggested by the presence of regressing cells neighboring the actively secreting cells., ((c) 2008 S. Karger AG, Basel.)
- Published
- 2009
- Full Text
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