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1.
Clin Exp Immunol ; 194(1): 103-117, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30260475

RESUMEN

Polymorphonuclear (PMN) leucocytes participate in acute inflammatory pathologies such as acute respiratory distress syndrome (ARDS) following traumatic injury and shock, which also activates the coagulation system systemically. Trauma can prime the PMN nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex for an enhanced respiratory burst, but the relative role of various priming agents in this process remains incompletely understood. We therefore set out to identify mediators of PMN priming during coagulation and trauma-shock and determine whether PMN reactive oxygen species (ROS) generated in this manner could influence organ injury and coagulation. Initial experiments demonstrated that PMN are primed for predominantly extracellular ROS production by products of coagulation, which was abrogated by CD88/C5a receptor(C5aR) inhibition. The importance of this was highlighted further by demonstrating that known PMN priming agents result in fractionally different amounts of extracellular versus intracellular ROS release depending on the agent used. Plasma from trauma patients in haemodynamic shock (n = 10) also primed PMN for extracellular ROS in a C5a-dependent manner, which correlated with both complement alternative pathway activation and thrombin generation. Furthermore, PMN primed by preincubation with products of blood coagulation directly caused loss of endothelial barrier function in vitro that was abrogated by C5aR blockade or NADPH oxidase inhibition. Finally, we show in a murine model of trauma-shock that p47phox knock-out (KO) mice with PMN incapable of generating ROS were protected from inflammatory end-organ injury and activated protein C-mediated coagulopathy. In summary, we demonstrate that trauma-shock and coagulation primes PMN for predominantly extracellular ROS production in a C5a-dependent manner that contributes to endothelial barrier loss and organ injury, and potentially enhances traumatic coagulopathy.


Asunto(s)
Coagulación Sanguínea/fisiología , Neutrófilos/inmunología , Especies Reactivas de Oxígeno/metabolismo , Receptor de Anafilatoxina C5a/antagonistas & inhibidores , Choque/patología , Heridas y Lesiones/patología , Adulto , Anciano , Animales , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , NADPH Oxidasas/antagonistas & inhibidores , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Activación Neutrófila/inmunología , Estallido Respiratorio , Síndrome de Dificultad Respiratoria/inmunología , Síndrome de Dificultad Respiratoria/patología , Choque/inmunología , Trombina/biosíntesis , Heridas y Lesiones/inmunología
2.
Lett Appl Microbiol ; 67(1): 15-21, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29679390

RESUMEN

Irreversible electroporation (IRE) damages cell membranes and is used in medicine for nonthermal ablation of malignant tumours. Our aim was to evaluate the antimicrobial effect of IRE. The pathogenic micro-organisms, Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, Pseudomonas aeruginosa and Candida albicans were subjected to IRE. Survival was measured as a function of voltage and the number of pulses applied. Combined use of IRE and oxacillin for eradication of Staph. aureus was also tested. Log10 reduction in micro-organisms positively correlated with the number of applied pulses. The colony count of Strep. pyogenes and E. coli declined by 3·38 and 3·05 orders of magnitude, respectively, using an electric field of 2000 V and 100 pulses. Killing of Staph. aureus and P. aeruginosa was achieved with a double cycle of IRE (2000, 1500 V and repeated 1250 V respectively) of 50-100 IRE pulses. The addition of subclinical inhibitory concentrations of oxacillin to the Staph. aureus suspension prior to IRE led to total bacterial death, demonstrating synergism between oxacillin and IRE. Our results demonstrate that using IRE with clinically established parameters has a marked in vitro effect on pathogenic micro-organisms and highlights the potential of IRE as a treatment modality for deep-seated infections, particularly when combined with low doses of antibiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: Irreversible electroporation (IRE) is utilized in interventional radiology to treat cancer patients. In this study we evaluated in vitro the antimicrobial effect of IRE. We demonstrated that using IRE with clinically established parameters has a marked effect on pathogenic micro-organisms and is synergistic to antimicrobials when both are combined. Our results point to the potential of IRE as a treatment modality for deep-seated infections.


Asunto(s)
Candida albicans/crecimiento & desarrollo , Membrana Celular/patología , Electroporación/métodos , Escherichia coli/crecimiento & desarrollo , Pseudomonas aeruginosa/crecimiento & desarrollo , Staphylococcus aureus/crecimiento & desarrollo , Streptococcus pyogenes/crecimiento & desarrollo , Antibacterianos/farmacología , Recuento de Colonia Microbiana , Humanos , Oxacilina/farmacología
3.
J Virol ; 87(18): 10348-55, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23864635

RESUMEN

Human adenovirus E1A makes extensive connections with the cellular protein interaction network. By doing so, E1A can manipulate many cellular programs, including cell cycle progression. Through these reprogramming events, E1A functions as a growth-promoting oncogene and has been used extensively to investigate mechanisms contributing to oncogenesis. Nevertheless, it remains unclear how the C-terminal region of E1A contributes to oncogenic transformation. Although this region is required for transformation in cooperation with E1B, it paradoxically suppresses transformation in cooperation with activated Ras. Previous analysis has suggested that the interaction of E1A with CtBP plays a pivotal role in both activities. However, some C-terminal mutants of E1A retain CtBP binding and yet exhibit defects in transformation, suggesting that other targets of this region are also necessary. To explore the roles of these additional factors, we performed an extensive mutational analysis of the C terminus of E1A. We identified key residues that are specifically required for binding all known targets of the C terminus of E1A. We further tested each mutant for the ability to both localize to the nucleus and transform primary rat cells in cooperation with E1B-55K or Ras. Interaction of E1A with importin α3/Qip1, dual-specificity tyrosine-regulated kinase 1A (DYRK1A), HAN11, and CtBP influenced transformation with E1B-55K. Interestingly, the interaction of E1A with DYRK1A and HAN11 appeared to play a role in suppression of transformation by activated Ras whereas interaction with CtBP was not necessary. This unexpected result suggests a need for revision of current models and provides new insight into transformation by the C terminus of E1A.


Asunto(s)
Adenoviridae/patogenicidad , Proteínas E1A de Adenovirus/metabolismo , Oxidorreductasas de Alcohol/metabolismo , Transformación Celular Viral , Proteínas de Unión al ADN/metabolismo , Adenoviridae/genética , Proteínas E1A de Adenovirus/genética , Animales , Línea Celular , Análisis Mutacional de ADN , Humanos , Mapeo de Interacción de Proteínas , Ratas
4.
Br J Surg ; 99(4): 487-93, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22287099

RESUMEN

BACKGROUND: With higher-throughput data acquisition and processing, increasing computational power, and advancing computer and mathematical techniques, modelling of clinical and biological data is advancing rapidly. Although exciting, the goal of recreating or surpassing in silico the clinical insight of the experienced clinician remains difficult. Advances toward this goal and a brief overview of various modelling and statistical techniques constitute the purpose of this review. METHODS: A review of the literature and experience with models and physiological state representation and prediction after injury was undertaken. RESULTS: A brief overview of models and the thinking behind their use for surgeons new to the field is presented, including an introduction to visualization and modelling work in surgical care, discussion of state identification and prediction, discussion of causal inference statistical approaches, and a brief introduction to new vital signs and waveform analysis. CONCLUSION: Modelling in surgical critical care can provide a useful adjunct to traditional reductionist biological and clinical analysis. Ultimately the goal is to model computationally the clinical acumen of the experienced clinician.


Asunto(s)
Cuidados Críticos/métodos , Enfermedad Crítica/terapia , Modelos Biológicos , Fenómenos Fisiológicos , Procedimientos Quirúrgicos Operativos , Humanos
5.
J Trauma ; 71(2 Suppl 3): S329-36, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21814100

RESUMEN

BACKGROUND: Administration of high transfusion ratios in patients not requiring massive transfusion might be harmful. We aimed to determine the effect of high ratios of fresh frozen plasma (FFP) and platelets (PLT) to packed red blood cells (PRBC) in nonmassively transfused patients. METHODS: Records of 1,788 transfused trauma patients who received <10 units of PRBC in 24 hours at 23 United States Level I trauma centers were reviewed. The relationship between ratio category (low and high) and in-hospital mortality was assessed with propensity-adjusted multivariate proportional hazards models. RESULTS: At baseline, patients transfused with a high FFP:PRBC ratio were younger, had a lower Glasgow Coma Scale score, and a higher Injury Severity Score. Those receiving a high PLT:PRBC ratio were older. The risk of in-hospital mortality did not vary significantly with FFP:PRBC ratio category. Intensive care unit (ICU)-free days, hospital-free days, and ventilator-free days did not vary significantly with FFP:PRBC ratio category. ICU-free days and ventilator-free days were significantly decreased among patients in the high (≥1:1) PLT:PRBC category, and hospital-free days did not vary significantly with PLT:PRBC ratio category. The analysis was repeated using 1:2 as the cutoff for high and low ratios. Using this cutoff, there was still no difference in mortality with either FFP:PRBC ratios or platelet:PRBC ratios. However, patients receiving a >1:2 ratio of FFP:PRBCs or a >1:2 ratio PLT:PRBCs had significantly decreased ICU-free days and ventilator-free days. CONCLUSIONS: FFP:PRBC and PLT:PRBC ratios were not associated with in-hospital mortality. Depending on the threshold analyzed, a high ratio of FFP:PRBC and PLT:PRBC transfusion was associated with fewer ICU-free days and fewer ventilator-free days, suggesting that the damage control infusion of FFP and PLT may cause increased morbidity in nonmassively transfused patients and should be rapidly terminated when it becomes clear that a massive transfusion will not be required.


Asunto(s)
Transfusión de Componentes Sanguíneos , Hemorragia/mortalidad , Hemorragia/terapia , Heridas y Lesiones/mortalidad , Adulto , Servicio de Urgencia en Hospital , Recuento de Eritrocitos , Femenino , Hemorragia/sangre , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Estudios Retrospectivos , Resultado del Tratamiento , Heridas y Lesiones/sangre , Heridas y Lesiones/terapia , Adulto Joven
6.
J Trauma ; 71(2 Suppl 3): S343-52, 2011 08.
Artículo en Inglés | MEDLINE | ID: mdl-21814102

RESUMEN

BACKGROUND: The effect of blood component ratios on the survival of patients with traumatic brain injury (TBI) has not been studied. METHODS: A database of patients transfused in the first 24 hours after admission for injury from 22 Level I trauma centers over an 18-month period was queried to find patients who (1) met different definitions of massive transfusion (5 units red blood cell [RBC] in 6 hours vs. 10 units RBC in 24 hours), (2) received high or low ratios of platelets or plasma to RBC units (<1:2 vs. ≥ 1:2), and (3) had severe TBI (head abbreviated injury score ≥ 3) (TBI+). RESULTS: Of 2,312 total patients, 850 patients were transfused with ≥ 5 RBC units in 6 hours and 807 could be classified into TBI+ (n = 281) or TBI- (n = 526). Six hundred forty-three patients were transfused with ≥ 10 RBC units in 24 hours with 622 classified into TBI+ (n = 220) and TBI- (n = 402). For both high-risk populations, a high ratio of platelets:RBCs (not plasma) was independently associated with improved 30-day survival for patients with TBI+ and a high ratio of plasma:RBCs (not platelets) was independently associated with improved 30-day survival in TBI- patients. CONCLUSIONS: High platelet ratio was associated with improved survival in TBI+ patients while a high plasma ratio was associated with improved survival in TBI- patients. Prospective studies of blood product ratios should include TBI in the analysis for determination of optimal use of ratios on outcome in injured patients.


Asunto(s)
Transfusión de Componentes Sanguíneos , Lesiones Encefálicas/mortalidad , Lesiones Encefálicas/terapia , Adulto , Lesiones Encefálicas/sangre , Recuento de Eritrocitos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Estudios Retrospectivos , Tasa de Supervivencia , Centros Traumatológicos , Resultado del Tratamiento , Adulto Joven
7.
J Trauma ; 71(2 Suppl 3): S353-7, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21814103

RESUMEN

BACKGROUND: Recent data suggest that massively transfused patients have lower mortality rates when high ratios (>1:2) of plasma or platelets to red blood cells (RBCs) are used. Blunt and penetrating trauma patients have different injury patterns and may respond differently to resuscitation. This study was performed to determine whether mortality after high product ratio massive transfusion is different in blunt and penetrating trauma patients. METHODS: Patients receiving 10 or more units of RBCs in the first 24 hours after admission to one of 23 Level I trauma centers were analyzed. Baseline physiologic and biochemical data were obtained. Univariate and logistic regression analyses were performed. Adjusted mortality in patients receiving high (≥ 1:2) and low (<1:2) ratios of plasma or platelets to RBCs was calculated for blunt and penetrating trauma patients. RESULTS: The cohort contained 703 patients. Blunt injury patients receiving a high ratio of plasma or platelets to RBCs had lower 24-hour mortality (22% vs. 31% for plasma, p = 0.007; 20% vs. 30% for platelets, p = 0.032), but there was no difference in 30-day mortality (40% vs. 44% for plasma, p = 0.085; 37% vs. 44% for platelets, p = 0.063). Patients with penetrating injuries receiving a high plasma:RBC ratio had lower 24-hour mortality (21% vs. 37%, p = 0.005) and 30-day mortality (29% vs. 45%, p = 0.005). High platelet:RBC ratios did not affect mortality in penetrating patients. CONCLUSION: Use of high plasma:RBC ratios during massive transfusion may benefit penetrating trauma patients to a greater degree than blunt trauma patients. High platelet:RBC ratios did not benefit either group.


Asunto(s)
Transfusión de Componentes Sanguíneos , Hemorragia/terapia , Heridas no Penetrantes/mortalidad , Heridas no Penetrantes/terapia , Heridas Penetrantes/mortalidad , Heridas Penetrantes/terapia , Adolescente , Adulto , Recuento de Eritrocitos , Femenino , Hemorragia/sangre , Hemorragia/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Estudios Retrospectivos , Tasa de Supervivencia , Centros Traumatológicos , Resultado del Tratamiento , Heridas no Penetrantes/sangre , Heridas Penetrantes/sangre , Adulto Joven
8.
J Trauma ; 71(2 Suppl 3): S364-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21814105

RESUMEN

BACKGROUND: Improvements in prehospital care and resuscitation have led to increases in the number of severely injured patients who are salvageable. Massive transfusion has been increasingly used. Patients often present with markedly abnormal physiologic and biochemical data. The purpose of this study was to identify objective data that can be used to identify clinical futility in massively transfused trauma patients to allow for early termination of resuscitative efforts. METHODS: A multicenter database was used. Initial physiologic and biochemical data were obtained, and mortality was determined for patients in the 5th and 10th percentiles for each variable. Raw data from the extreme outliers for each variable were also examined to determine whether a point of excessive mortality could be identified. Injury scoring data were also analyzed. A classification tree model was used to look for variable combinations that predict clinical futility. RESULTS: The cohort included 704 patients. Overall mortality was 40.2%. The highest mortality rates were seen in patients in the 10th percentile for lactate (77%) and pH (72%). Survivors at the extreme ends of the distribution curves for each variable were not uncommon. The classification tree analysis failed to identify any biochemical and physiologic variable combination predictive of >90% mortality. Patients older than 65 years with severe head injuries had 100% mortality. CONCLUSION: Consideration should be given to withholding massive transfusion for patients older than 65 years with severe head injuries. Otherwise we did not identify any objective variables that reliably predict clinical futility in individual cases. Significant survival rates can be expected even in patients with profoundly abnormal physiologic and biochemical data.


Asunto(s)
Transfusión Sanguínea , Hemorragia/metabolismo , Hemorragia/fisiopatología , Inutilidad Médica , Heridas y Lesiones/metabolismo , Heridas y Lesiones/fisiopatología , Adulto , Anciano , Femenino , Hemorragia/terapia , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Resucitación , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Heridas y Lesiones/mortalidad , Adulto Joven
9.
J Trauma ; 71(2 Suppl 3): S370-4, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21814106

RESUMEN

BACKGROUND: Improvements in trauma systems and resuscitation have increased survival in severely injured patients. Massive transfusion has been increasingly used in the civilian setting. Objective predictors of mortality have not been well described. This study examined data available in the early postinjury period to identify variables that are predictive of 24-hour- and 30-day mortality in massively transfused trauma patients. METHODS: Massively transfused trauma patients from 23 Level I centers were studied. Variables available on patient arrival that were predictive of mortality at 24 hours were entered into a logistic regression model. A second model was created adding data available 6 hours after injury. A third model evaluated mortality at 30 days. Receiver operating characteristic curves and the Hosmer-Lemeshow test were used to assess model quality. RESULTS: Seven hundred four massively transfused patients were analyzed. The model best able to predict 24-hour mortality included pH, Glasgow Coma Scale score, and heart rate, with an area under the receiver operating characteristic curve (AUROC) of 0.747. Addition of the 6-hour red blood cell requirement increased the AUROC to 0.769. The model best able to predict 30-day mortality included the above variables plus age and Injury Severity Score with an AUROC of 0.828. CONCLUSION: Glasgow Coma Scale score, pH, heart rate, age, Injury Severity Score, and 6-hour red blood cell transfusion requirement independently predict mortality in massively transfused trauma patients. Models incorporating these data have only a modest ability to predict mortality and should not be used to justify withholding massive transfusion in individual cases.


Asunto(s)
Transfusión Sanguínea , Hemorragia/mortalidad , Hemorragia/terapia , Heridas y Lesiones/mortalidad , Heridas y Lesiones/terapia , Adulto , Femenino , Hemorragia/etiología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Índices de Gravedad del Trauma , Heridas y Lesiones/complicaciones , Adulto Joven
10.
J Trauma ; 71(2 Suppl 3): S375-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21814107

RESUMEN

BACKGROUND: Recent data suggest that patients undergoing massive transfusion have lower mortality rates when ratios of plasma and platelets to red blood cells (RBCs) of ≥ 1:2 are used. This has not been examined independently in women and men. A gender dichotomy in outcome after severe injury is known to exist. This study examined gender-related differences in mortality after high product ratio massive transfusion. METHODS: A retrospective study was conducted using a database containing massively transfused trauma patients from 23 Level I trauma centers. Baseline demographic, physiologic, and biochemical data were obtained. Univariate and logistic regression analyses were performed. Adjusted mortality in patients receiving high (≥ 1:2) or low (<1:2) ratios of plasma or platelets to RBCs was compared in women and men independently. RESULTS: Seven hundred four patients were analyzed. In males, mortality was lower for patients receiving a high plasma:RBC ratio at 24 hours (20.6% vs. 33.0% for low ratio, p = 0.005) and at 30 days (34.9% vs. 42.8%, p = 0.032). Males receiving a high platelet:RBC ratio also had lower 24-hour mortality (17.6% vs. 31.5%, p = 0.004) and 30-day mortality (32.1% vs. 42.2%, p = 0.045). Females receiving high ratios of plasma or platelets to RBCs had no improvement in 24-hour mortality (p = 0.119 and 0.329, respectively) or 30-day mortality (p = 0.199 and 0.911, respectively). Use of high product ratio transfusions did not affect 24-hour RBC requirements in males or females. CONCLUSION: Use of high plasma:RBC or platelet:RBC ratios in massive transfusion may benefit men more than women. This may be due to gender-related differences in coagulability. Further study is needed to determine whether separate protocols for women and men should be established.


Asunto(s)
Transfusión Sanguínea , Hemorragia/mortalidad , Hemorragia/terapia , Heridas y Lesiones/mortalidad , Heridas y Lesiones/terapia , Adulto , Recuento de Eritrocitos , Femenino , Hemorragia/sangre , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Estudios Retrospectivos , Factores Sexuales , Tasa de Supervivencia , Centros Traumatológicos , Heridas y Lesiones/sangre , Adulto Joven
11.
J Trauma ; 71(2 Suppl 3): S380-3, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21814108

RESUMEN

BACKGROUND: Current trauma resuscitation guidelines recommend giving an initial crystalloid bolus as first line for resuscitation. Recent studies have shown a survival benefit for trauma patients resuscitated with high ratios of fresh frozen plasma (FFP) to packed red blood cells (PRBC). Our aim was to determine whether the volume of crystalloid given during resuscitation correlated with differences in morbidity or mortality based on the ratio of FFP:PRBC given. METHODS: This was a retrospective review of 2,473 transfused trauma patients at 23 Level I trauma centers from July 2005 to October 2007. Patients were separated based on the ratios of FFP:PRBC they received (<1:4, 1:4-1:1, and >1:1) and then analyzed for morbidity and mortality based on whether or not they received at least 1 L crystalloid for each unit of PRBC. Outcomes analyzed were 6-hour, 24-hour, and 30-day survival as well as intensive care unit (ICU)-free days, ventilator-free days, and hospital-free days. RESULTS: Massive transfusion patients who received <1:4 ratios of FFP:PRBC had significantly improved 6-hour, 24-hour, and 30-day mortality and significantly more ventilator-free days if they received at least 1 L of crystalloid for each unit of PRBC. Nonmassive transfusion patients who received <1:4 ratios of FFP:PRBC had significantly improved 6-hour, 24-hour, and 30-day mortality and significantly more ICU-free days, ventilator-free days, and hospital-free days if they received at least 1 L crystalloid for each unit of PRBC. In both massive and nonmassive transfusion groups, the survival benefit and morbidity benefit was progressively less for the 1:4 to 1:1 FFP:PRBC groups and >1:1 FFP:PRBC groups. CONCLUSIONS: If high ratios of FFP:PRBC are unable to be given to trauma patients, resuscitation with at least 1 L of crystalloid per unit of PRBC is associated with improved overall mortality.


Asunto(s)
Transfusión Sanguínea , Hemorragia/mortalidad , Hemorragia/terapia , Soluciones Isotónicas/uso terapéutico , Heridas y Lesiones/mortalidad , Heridas y Lesiones/terapia , Soluciones Cristaloides , Recuento de Eritrocitos , Femenino , Hemorragia/sangre , Humanos , Masculino , Plasma , Recuento de Plaquetas , Resucitación , Estudios Retrospectivos , Tasa de Supervivencia , Heridas y Lesiones/sangre
12.
J Trauma ; 71(2 Suppl 3): S384-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21814109

RESUMEN

BACKGROUND: The Injury Severity Score (ISS) is widely used as a method for rating severity of injury. The ISS is the sum of the squares of the three worst Abbreviated Injury Scale (AIS) values from three body regions. Patients with penetrating injuries tend to have higher mortality rates for a given ISS than patients with blunt injuries. This is thought to be secondary to the increased prevalence of multiple severe injuries in the same body region in patients with penetrating injuries, which the ISS does not account for. We hypothesized that the mechanism-based difference in mortality could be attributed to certain ISS ranges and specific AIS values by body region. METHODS: Outcome and injury scoring data were obtained from transfused patients admitted to 23 Level I trauma centers. ISS values were grouped into categories, and a logistic regression model was created. Mortality for each ISS category was determined and compared with the ISS 1 to 15 group. An interaction term was added to evaluate the effect of mechanism. Additional logistic regression models were created to examine each AIS category individually. RESULTS: There were 2,292 patients in the cohort. An overall interaction between ISS and mechanism was observed (p = 0.049). Mortality rates between blunt and penetrating patients with an ISS between 25 and 40 were significantly different (23.6 vs. 36.1%; p = 0.022). Within this range, the magnitude of the difference in mortality was far higher for penetrating patients with head injuries (75% vs. 37% for blunt) than truncal injuries (26% vs. 17% for blunt). Penetrating trauma patients with an AIS head of 4 or 5, AIS abdomen of 3, or AIS extremity of 3 all had adjusted mortality rates higher than blunt trauma patients with those values. CONCLUSION: Significant differences in mortality between blunt and penetrating trauma patients exist at certain ISS and AIS category values. The mortality difference is greatest for head injured patients.


Asunto(s)
Traumatismo Múltiple/diagnóstico , Traumatismo Múltiple/mortalidad , Heridas Penetrantes/diagnóstico , Heridas Penetrantes/mortalidad , Escala Resumida de Traumatismos , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Modelos Logísticos , Masculino , Persona de Mediana Edad , Traumatismo Múltiple/complicaciones , Valor Predictivo de las Pruebas , Tasa de Supervivencia , Centros Traumatológicos , Heridas Penetrantes/complicaciones , Adulto Joven
13.
J Trauma ; 71(2 Suppl 3): S389-93, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21814110

RESUMEN

BACKGROUND: Significant differences in outcomes have been demonstrated between Level I trauma centers. Usually these differences are ascribed to regional or administrative differences, although the influence of variation in clinical practice is rarely considered. This study was undertaken to determine whether differences in early mortality of patients receiving a massive transfusion (MT, ≥ 10 units pf RBCs within 24 hours of admission) persist after adjustment for patient and transfusion practice differences. We hypothesized differences among centers in 24-hour mortality could predominantly be accounted for by differences in transfusion practices as well as patient characteristics. METHODS: Data were retrospectively collected over a 1-year period from 15 Level I centers on patients receiving an MT. A purposeful variable selection strategy was used to build the final multivariable logistic model to assess differences between centers in 24-hour mortality. Adjusted odds ratios for each center were calculated. RESULTS: : There were 550 patients evaluated, but only 443 patients had complete data for the set of variables included in the final model. Unadjusted mortality varied considerably across centers, ranging from 10% to 75%. Multivariable logistic regression identified injury severity score (ISS), abbreviated injury scale (AIS) of the chest, admission base deficit, admission heart rate, and total units of RBC transfused, as well as ratios of plasma:RBC and platelet:RBC to be associated with 24-hour mortality. After adjusting for severity of injury and transfusion, treatment variables between center differences were no longer significant. CONCLUSIONS: In the defined population of patients receiving an MT, between-center differences in 24-hour mortality may be accounted for by severity of injury as well as transfusion practices.


Asunto(s)
Transfusión Sanguínea , Hemorragia/mortalidad , Hemorragia/terapia , Centros Traumatológicos , Heridas y Lesiones/mortalidad , Heridas y Lesiones/terapia , Adulto , Anciano , Femenino , Mortalidad Hospitalaria , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Índices de Gravedad del Trauma , Resultado del Tratamiento , Adulto Joven
14.
J Trauma ; 71(2 Suppl 3): S318-28, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21814099

RESUMEN

BACKGROUND: Several recent military and civilian trauma studies demonstrate that improved outcomes are associated with early and increased use of plasma-based resuscitation strategies. However, outcomes associated with platelet transfusions are poorly characterized. We hypothesized that increased platelet:red blood cells (RBC) ratios would decrease hemorrhagic death and improve survival after massive transfusion (MT). METHODS: A transfusion database of patients transported from the scene to 22 Level I Trauma Centers over 12 months in 2005 to 2006 was reviewed. MT was defined as receiving ≥ 10 RBC units within 24 hours of admission. To mitigate survival bias, 25 patients who died within 60 minutes of arrival were excluded from analysis. Six random donor platelet units were considered equal to a single apheresis platelet unit. Admission and outcome data associated with the low (>1:20), medium (1:2), and high (1:1) platelet:RBC ratios were examined. These groups were based on the median value of the tertiles for the ratio of platelets:RBC units. RESULTS: Two thousand three hundred twelve patients received at least one unit of blood and 643 received an MT. Admission vital signs, INR, temperature, pH, Glasgow Coma Scale, Injury Severity Score, and age were similar between platelet ratio groups. The average admission platelet counts were lower in the patients who received the high platelet:RBC ratio versus the low ratio (192 vs. 216, p = 0.03). Patients who received MT were severely injured, with a mean (± standard deviation) Injury Severity Score of 33 ± 16 and received 22 ± 15 RBCs and 11 ± 14 platelets within 24 hours of injury. Increased platelet ratios were associated with improved survival at 24 hours and 30 days (p < 0.001 for both). Truncal hemorrhage as a cause of death was decreased (low: 67%, medium: 60%, high: 47%, p = 0.04). Multiple organ failure mortality was increased (low: 7%, medium: 16%, high: 27%, p = 0.003), but overall 30-day survival was improved (low: 52%, medium: 57%, high: 70%) in the high ratio group (medium vs. high: p = 0.008; low vs. high: p = 0.007). CONCLUSION: Similar to recently published military data, transfusion of platelet:RBC ratios of 1:1 was associated with improved early and late survival, decreased hemorrhagic death and a concomitant increase in multiple organ failure-related mortality. Based on this large retrospective study, increased and early use of platelets may be justified, pending the results of prospective randomized transfusion data.


Asunto(s)
Transfusión Sanguínea , Hemorragia/sangre , Hemorragia/terapia , Heridas y Lesiones/sangre , Heridas y Lesiones/mortalidad , Adulto , Servicio de Urgencia en Hospital , Recuento de Eritrocitos , Femenino , Hemorragia/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento , Heridas y Lesiones/terapia , Adulto Joven
15.
Intern Emerg Med ; 15(2): 257-262, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31352654

RESUMEN

We sought to assess the role of procalcitonin in discriminating severe bacterial infections requiring antibiotic treatment from non-bacterial causes of fever or chills in chronic dialysis patients. Chronic hemodialysis patients who were admitted to the emergency room due to fever and/or chills were recruited to the study. The presence or absence of bacterial infection was defined after recruitment conclusion by an infectious disease specialist who was blinded to procalcitonin results. Procalcitonin levels were compared between infected and non-infected patients. Out of 54 patients recruited, 22 (41%) patients eventually diagnosed with infection. Mean (± SD) procalcitonin values were 4.3 (± 5.5) ng/ml among cases, 1.0 (± 2.0) ng/ml among controls with no infection (p = 0.02). A cutoff PCT value of 1 ng/ml or higher had 77% sensitivity and 59% specificity for the diagnosis of severe infection. Procalcitonin cannot usefully identify hemodialysis patient with bacterial infection.


Asunto(s)
Bacteriemia/diagnóstico , Polipéptido alfa Relacionado con Calcitonina/análisis , Diálisis Renal/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Bacteriemia/sangre , Bacteriemia/complicaciones , Biomarcadores/análisis , Biomarcadores/sangre , Escalofríos/sangre , Escalofríos/etiología , Servicio de Urgencia en Hospital/organización & administración , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Fiebre/sangre , Fiebre/etiología , Humanos , Masculino , Persona de Mediana Edad , Polipéptido alfa Relacionado con Calcitonina/sangre , Curva ROC , Diálisis Renal/métodos
16.
Clin Microbiol Infect ; 26(4): 470-474, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31539635

RESUMEN

OBJECTIVES: Blood culture contamination carries risks for patients, such as unnecessary antimicrobial therapy and other additional hazards and costs. One method shown to be effective in reducing contamination is initial blood specimen diversion during collection. We hypothesized that initial blood specimen diversion without a designated device or procedure would suffice for reduction in blood culture contamination rate. METHODS: From 1 September 2017 through to 6 September 2018, we conducted a randomized controlled trial to assess the effect of an initial-specimen diversion technique (ISDT) on the rate of blood-culture contamination by changing the order of sampling using regular vacuum specimen tubes instead of commercially available sterile diversion devices. We included adults from whom the treating physician planned to take blood cultures and additional blood chemistry tests. Additionally, we evaluated the potential economic benefits of an ISDT. This was a researcher-initiated trial, Clinicaltrials.gov NCT03088865. RESULTS: In all, 756 patients were enrolled. This method, compared with the standard procedure in use at our medical centre, reduced contamination by 66% (95% CI 17%-86%), from 20/400 (5%) with the standard method to 6/356 (1.6%) with the ISDT, without compromising detection of true bloodstream infection and at no additional cost. Hospital-wide implementation of ISDT was associated with a 1.1% saving in hospitalization days. CONCLUSIONS: We offer this novel approach as a simple, cost-effective measure to reduce risks to patient safety from contaminated blood cultures, without the need for using costly devices.


Asunto(s)
Cultivo de Sangre/economía , Cultivo de Sangre/métodos , Recolección de Muestras de Sangre/métodos , Costos y Análisis de Costo , Manejo de Especímenes/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Recolección de Muestras de Sangre/economía , Recolección de Muestras de Sangre/instrumentación , Femenino , Hospitales , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Manejo de Especímenes/economía , Manejo de Especímenes/instrumentación , Adulto Joven
17.
Clin Microbiol Infect ; 26(5): 637-642, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31499179

RESUMEN

OBJECTIVES: The 2018 measles outbreak in Israel affected >2000 people in Jerusalem. The aim of the study was to describe clinical features and complications of hospitalized measles patients in Jerusalem, as related to age group and risk factors. METHODS: All individuals hospitalized with measles in the three main hospitals in Jerusalem during March 2018 to February 2019 were included. Demographic, clinical and laboratory data were analysed. RESULTS: Of 161 hospitalized individuals, 86 (53.4%) were <5 years old, 16 (10%) were ≥5 years but <20 years old, and 59 (36.6%) were ≥20 years old. Most, 114/135 (85%), were unvaccinated. Immunocompromised state was identified in 12/161 (7.5%) patients, 20/161 (12.4%) had other underlying co-morbidities, and four were pregnant. Hypoxaemia on admission was a common finding in all age groups. Hepatitis was more common among adults ≥20 years old (33/59, 59%). Measles-related complications were noted in 95/161 (59%) patients, and included pneumonia/pneumonitis (67/161, 41.6%), which was more common in young (<5 years) children, diarrhoea (18/161, 11.2%), otitis (18/161, 11.2%), and neurological complications (6/161, 3.7%)-the latter occurring more frequently in the 5- to 20-year age group. Two of the 12 immunocompromised patients died of measles-related complications. A high re-admission rate (19/161, 11.8%) within 3 months was documented among hospitalized measles patients. CONCLUSION: The burden of hospitalization, as well as the high rate of short- and long-term complications observed in hospitalized patients, underscore the importance of maintaining a high measles vaccine coverage, with enhanced targeting of unvaccinated population pockets.


Asunto(s)
Brotes de Enfermedades , Hospitalización/estadística & datos numéricos , Sarampión/complicaciones , Sarampión/epidemiología , Brotes de Enfermedades/prevención & control , Brotes de Enfermedades/estadística & datos numéricos , Femenino , Humanos , Israel/epidemiología , Masculino , Sarampión/patología , Sarampión/prevención & control , Vacuna Antisarampión/administración & dosificación , Factores de Riesgo , Vacunación/estadística & datos numéricos
18.
Science ; 156(3782): 1640-3, 1967 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-6026661

RESUMEN

Wihtin 5 days after the leg nerves of a cockroach are injured, miniature end-plate potentials have disappeared. and the muscle is unresponsive to electrical stimulation. The soma of the injured neutron has a dense perinuclear ring of RNA. By 40 days after the injury, locomotor activity has returned, and the miniature end-plate potentials and evoked electrical responses have reappeared in the muscle. The RNA ring has disappeared, and the nucleus of the regenerating neuron has shifted to an eccentric position.


Asunto(s)
Ganglios/fisiología , Neuronas Motoras/fisiología , Regeneración Nerviosa , Unión Neuromuscular/fisiología , Potenciales Evocados , Insectos , Masculino , Neuronas Motoras/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Traumatismos de los Nervios Periféricos , ARN/metabolismo
19.
Science ; 156(3782): 1638-40, 1967 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-6025126

RESUMEN

When a metathoracic ganglion from one cockroach (Periplaneta americana) is transplanted into the coxa of another cockroach, it innervates only those leg muscles that have been previously denervated. The transplanted ganglion evokes hyperpolarizing synaptic potentials in the host muscles that it innervates. These potentials are correlated with twitching of the host limb.


Asunto(s)
Ganglios/trasplante , Músculos/inervación , Unión Neuromuscular/fisiología , Sinapsis/anatomía & histología , Sinapsis/fisiología , Animales , Electrofisiología , Insectos
20.
Science ; 213(4508): 611-7, 1981 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-7256258

RESUMEN

After a weak, steady electric current of approximately 10 microamperes was imposed across the completely severed spinal cord of the larval lamprey Petromyzon marinus, enhanced regeneration was observed in the severed giant reticulospinal neurons. The current was applied with implanted wick electrodes for 5 to 6 days after transection (cathode distal to lesion). The spinal cords were examined 44 to 63 days after the operation by means of intracellular fluorescent dye injections and electrophysiology. Extracellular stimulation of whole cords showed that action potentials in most of the electrically treated preparations were conducted in both directions across the lesion, but they were not conducted in either direction in most of the sham-treated controls. In most of the electrically treated animals, processes from giant axons with swollen irregular tips, indicating active growth, were seen in or across the lesion. Only a few of the sham-treated controls showed these features. It is possible that these facilitated regenerative responses were mediated by the effects of the artificially applied electric fields on the natural steady current of injury entering the spinal lesion.


Asunto(s)
Peces/fisiología , Lampreas/fisiología , Regeneración Nerviosa , Médula Espinal/fisiología , Potenciales de Acción , Animales , Axones/fisiología , Estimulación Eléctrica , Potenciales Evocados , Larva , Terminaciones Nerviosas/fisiología
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