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INTRODUCTION: International humanitarian law requires emergency medical support for both military personnel and civilians, including children. Here we present a detailed review of paediatric admissions with the pattern of injury and the resources they consume. METHODS: All paediatric admissions to the hospital at Camp Bastion between 1 January and 29 April 2011 were analysed prospectively. Data collected included time and date of admission, patient age and weight, mechanism of injury, extent of wounding, treatment, length of hospital stay and discharge destination. RESULTS: Eighty-five children (65 boys and 17 girls, median age: 8 years, median weight: 20 kg) were admitted. In 63% of cases the indication for admission was battle related trauma and in 31% non-battle trauma. Of the blast injuries, 51% were due to improvised explosive devices. Non-battle emergencies were mainly due to domestic burns (46%) and road traffic accidents (29%). The most affected anatomical area was the extremities (44% of injuries). Over 30% of patients had critical injuries. Operative intervention was required in 74% of cases. The median time to theatre for all patients was 52 minutes; 3 patients with critical injuries went straight to theatre in a median of 7 minutes. A blood transfusion was required in 27 patients; 6 patients needed a massive transfusion. Computed tomography was performed on 62% of all trauma admissions and 40% of patients went to the intensive care unit. The mean length of stay was 2 days (range: 1-26 days) and there were 7 deaths. CONCLUSIONS: Paediatric admissions make up a small but significant part of admissions to the hospital at Camp Bastion. The proportion of serious injuries is very high in comparison with admissions to a UK paediatric emergency department. The concentration of major injuries means that lessons learnt in terms of teamwork, the speed of transfer to theatre and massive transfusion protocols could be applied to UK paediatric practice.
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Hospitalización/estadística & datos numéricos , Hospitales Militares/estadística & datos numéricos , Heridas y Lesiones/epidemiología , Adolescente , Campaña Afgana 2001- , Afganistán/epidemiología , Distribución por Edad , Traumatismos por Explosión/epidemiología , Traumatismos por Explosión/terapia , Transfusión Sanguínea/estadística & datos numéricos , Quemaduras/epidemiología , Quemaduras/terapia , Niño , Preescolar , Tratamiento de Urgencia/estadística & datos numéricos , Femenino , Recursos en Salud/estadística & datos numéricos , Humanos , Lactante , Masculino , Auditoría Médica , Heridas y Lesiones/terapia , Heridas por Arma de Fuego/epidemiología , Heridas por Arma de Fuego/terapiaRESUMEN
Haemorrhage from severe pelvic fractures can be associated with significant mortality. Modern civilian trauma centres may manage these injuries with a combination of external pelvic fixation, extra-peritoneal packing and/or selective angiography; however, military patterns of wounding are different and deployed medical facilities may be resource constrained. We report two successful instances of pelvic packing using chitosan impregnated gauze (Celox) when conventional surgical attempts at vascular control had failed. We conclude that pelvic packing should be considered early in patients with military pelvic trauma and major haemorrhage, as part of damage control surgery and that Celox gauze may be a useful adjunct. In our cases, the Celox gauze was easily removed after 24-48 hours without significant bowel adhesions and did not leave a residual phelgmon (of exudate or gel) that may predispose to infection.
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Biopolímeros/uso terapéutico , Fracturas Óseas/complicaciones , Hemorragia/terapia , Técnicas Hemostáticas/instrumentación , Huesos Pélvicos/lesiones , Heridas Penetrantes/complicaciones , Adulto , Vendajes , Fijación de Fractura/métodos , Fracturas Óseas/diagnóstico , Fracturas Óseas/cirugía , Hemorragia/etiología , Humanos , Imagenología Tridimensional , Masculino , Personal Militar , Huesos Pélvicos/cirugía , Tomografía Computarizada por Rayos X , Índices de Gravedad del Trauma , Heridas Penetrantes/diagnóstico , Heridas Penetrantes/cirugía , Adulto JovenRESUMEN
OBJECTIVE: The purpose of this study was to assess the impact on patient outcome and hospital performance of preparing for and achieving American College of Surgeons (ACS) Level I trauma verification. METHODS: The center was a previously designated state regional trauma center located adjacent to a major metropolitan area. Preparation for ACS verification began in early 1996 and was completed in early 1998. Final verification took place in April 1999. Data were analyzed before (1994) and after (1998) the process. There was a marked increase in administrative support with trauma named one of the hospital's six centers of excellence. Two full-time board-certified trauma/critical care surgeons were added to the current six trauma surgeons. Their major focus was trauma care. Trauma support staff was also increased with case managers, a trauma nurse practitioner, additional trauma registrars, and administrative support staff. Education and continuous quality improvement were markedly expanded starting in 1996. RESULTS: There were 1,098 trauma patients admitted in 1994, and 1,658 in 1998. Overall mortality decreased (1994, 7.38%; 1998, 5.37%; p < 0.05). There was a marked decrease in mortality for severely injured (Injury Severity Score > 30) patients (1994, 44% mortality [38 of 86]; 1998, 27% [22 of 80]; p < 0.04). Average length of stay also decreased (1994, 12.22 days; 1998, 9.87 days; p < 0.02). This yielded an estimated cost savings for 1998 of greater than $4,000 per patient (total saving estimate of $7.4 million). CONCLUSION: Trauma system improvement as related to achieving ACS Level I verification appeared to have a positive impact on survival and patient care. There were cost savings realized that helped alleviate the added expense of this system improvement. The process of achieving ACS Level I verification is worthwhile and can be cost effective.
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Evaluación de Procesos y Resultados en Atención de Salud , Garantía de la Calidad de Atención de Salud/economía , Centros Traumatológicos/economía , Heridas y Lesiones/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Análisis Costo-Beneficio , Femenino , Mortalidad Hospitalaria , Humanos , Lactante , Masculino , Persona de Mediana Edad , New York , Heridas y Lesiones/economía , Heridas y Lesiones/mortalidadRESUMEN
OBJECTIVE: Logistic regression (LR), commonly used for hospital mortality prediction, has limitations. Artificial neural networks (ANNs) have been proposed as an alternative. We compared the performance of these approaches by using stepwise reductions in sample size. DESIGN: Prospective cohort study. SETTING: Seven intensive care units (ICU) at one tertiary care center. PATIENTS: Patients were 1,647 ICU admissions for whom first-day Acute Physiology and Chronic Health Evaluation III variables were collected. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We constructed LR and ANN models on a random set of 1,200 admissions (development set) and used the remaining 447 as the validation set. We repeated model construction on progressively smaller development sets (800, 400, and 200 admissions) and retested on the original validation set (n = 447). For each development set, we constructed models from two LR and two ANN architectures, organizing the independent variables differently. With the 1,200-admission development set, all models had good fit and discrimination on the validation set, where fit was assessed by the Hosmer-Lemeshow C statistic (range, 10.6-15.3; p > or = .05) and standardized mortality ratio (SMR) (range, 0.93 [95% confidence interval, 0.79-1.15] to 1.09 [95% confidence interval, 0.89-1.38]), and discrimination was assessed by the area under the receiver operating characteristic curve (range, 0.80-0.84). As development set sample size decreased, model performance on the validation set deteriorated rapidly, although the ANNs retained marginally better fit at 800 (best C statistic was 26.3 [p = .0009] and 13.1 [p = .11] for the LR and ANN models). Below 800, fit was poor with both approaches, with high C statistics (ranging from 22.8 [p <.004] to 633 [p <.0001]) and highly biased SMRs (seven of the eight models below 800 had SMRs of <0.85, with an upper confidence interval of <1). Discrimination ranged from 0.74 to 0.84 below 800. CONCLUSIONS: When sample size is adequate, LR and ANN models have similar performance. However, development sets of < or = 800 were generally inadequate. This is concerning, given typical sample sizes used for individual ICU mortality prediction.
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Mortalidad Hospitalaria , Unidades de Cuidados Intensivos/estadística & datos numéricos , Modelos Logísticos , Redes Neurales de la Computación , APACHE , Anciano , Análisis de Varianza , Intervalos de Confianza , Análisis Discriminante , Femenino , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Admisión del Paciente/estadística & datos numéricos , Pennsylvania/epidemiología , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Tamaño de la MuestraRESUMEN
BACKGROUND: To develop and validate an artificial neural network (ANN) for predicting survival of trauma patients based on standard prehospital variables, emergency room admission variables, and Injury Severity Score (ISS) using data derived from a regional area trauma system, and to compare this model with known trauma scoring systems. PATIENT POPULATION: The study was composed of 10,609 patients admitted to 24 hospitals comprising a seven-county suburban/rural trauma region adjacent to a major metropolitan area. The data was generated as part of the New York State trauma registry. Study period was from January 1993 through December 1996 (1993-1994: 5,168 patients; 1995: 2,768 patients; 1996: 2,673 patients). METHODS: A standard feed-forward back-propagation neural network was developed using Glasgow Coma Scale, systolic blood pressure, heart rate, respiratory rate, temperature, hematocrit, age, sex, intubation status, ICD-9-CM Injury E-code, and ISS as input variables. The network had a single layer of hidden nodes. Initial network development of the model was performed on the 1993-1994 data. Subsequent models were generated using the 1993, 1994, and 1995 data. The model was tested first on the 1995 and then on the 1996 data. The ANN model was tested against Trauma and Injury Severity Score (TRISS) and ISS using the receiver operator characteristic (ROC) area under the curve [ROC-A(z)], Lemeshow-Hosmer C-statistic, and calibration curves. RESULTS: The ANN showed good clustering of the data, with good separation of nonsurvivors and survivors. The ROCA(z) was 0.912 for the ANN, 0.895 for TRISS, and 0.766 for ISS. The ANN exceeded TRISS with respect to calibration (Lemeshow-Hosmer C-statistic: 7.4 for ANN; 17.1 for TRISS). The prediction of survivors was good for both models. The ANN exceeded TRISS in nonsurvivor prediction. CONCLUSION: An ANN developed for trauma patients using prehospital, emergency room admission data, and ISS gave good prediction of survival. It was accurate and had excellent calibration. This study expands our previous results developed at a single Level I trauma center and shows that an ANN model for predicting trauma deaths can be applied across hospitals with good results
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Redes Neurales de la Computación , Heridas y Lesiones/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Servicio de Urgencia en Hospital , Femenino , Escala de Coma de Glasgow , Humanos , Lactante , Recién Nacido , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , New York/epidemiología , Valor Predictivo de las Pruebas , Curva ROC , Reproducibilidad de los Resultados , Salud Rural , Análisis de SupervivenciaRESUMEN
OBJECTIVE: To assess the mortality rate and complications in a population of surgical patients with severe adult respiratory distress syndrome (ARDS) treated with positive end-expiratory pressure (PEEP) of > 15 cm H2O in an attempt to reduce intrapulmonary shunt to approximately 0.20 and reduce FIO2 to < 0.50. DESIGN: Retrospective review of patients treated by a standardized ventilatory support protocol at the time of their illness. SETTING: A 24-bed surgical intensive care unit in a university medical center. PATIENTS: All patients admitted to the surgical intensive care unit during a 34-month period who met the criteria for severe ARDS (Pao2 of < or = 70 torr [< or = 9.3 kPa] on an FIO2 of > or = 0.50, diffuse interstitial and/or alveolar infiltrates on chest radiograph, decreased lung compliance, no evidence of congestive heart failure, and a likely predisposing etiology) were evaluated. Patients treated with PEEP of > 15 cm H2O were selected for this review. INTERVENTIONS: Patients were treated by a protocol to achieve oxygenation end points, which consisted of maintaining arterial oxyhemoglobin saturation (as determined by pulse oximetry of > or = 0.92), while reducing FIO2 to < 0.50 and decreasing intrapulmonary shunt fraction to < or = 0.20 by adding PEEP. With the exception of patients with suspected intracranial hypertension related to closed-head injury, low-rate intermittent mandatory ventilation was the primary mode of ventilation. Pressure-support ventilation was added, when needed, to improve patient comfort, enhance spontaneous tidal volume, or improve CO2 excretion. MEASUREMENTS AND MAIN RESULTS: Eighty-six patients with severe ARDS were treated with a PEEP of > 15 cm H2O. Nineteen of these patients died early of severe closed-head injury or massive uncontrollable hemorrhage and were excluded from the evaluation. The remaining 67 patients had a mean Lung Injury Score of 3.3 during their treatment with high PEEP. Twenty (30%) of 67 patients died. Eight of the deaths occurred after decrease of ventilatory support and with acceptable blood gases. The other 12 patients who died had continued oxygenation deficits and received increased levels of ventilatory support at the time of death. Twenty-six (39%) of 67 patients had radiographic manifestations of barotrauma (pneumothorax, subcutaneous emphysema, etc.) related to their primary injuries or to complications related to central venous catheter placement. Seven (17%) of 41 patients developed clinical or radiographic signs of barotrauma while receiving high-level PEEP. The hemodynamic effects of increased airway pressure were managed with fluids and inotropic agents, when necessary, and did not limit the application of PEEP to reach the defined end point of treatment. CONCLUSIONS: This subset of patients with severe ARDS treated with high-level PEEP had a mortality rate lower than those rates previously reported by other researchers using more conventional ventilatory support and resuscitation techniques. FIO2 may be significantly reduced and PaO2 may be maintained at acceptable values by decreasing intrapulmonary shunt fraction using high-level PEEP.
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Respiración con Presión Positiva , Síndrome de Dificultad Respiratoria/terapia , Adulto , Anciano , Barotrauma/etiología , Cuidados Críticos , Femenino , Humanos , Unidades de Cuidados Intensivos , Persona de Mediana Edad , Respiración con Presión Positiva/efectos adversos , Síndrome de Dificultad Respiratoria/complicaciones , Síndrome de Dificultad Respiratoria/mortalidad , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Heridas y Lesiones/complicaciones , Heridas y Lesiones/mortalidadRESUMEN
This study evaluated the effect of high-level positive end-expiratory pressure (PEEP) on mortality, barotrauma, intrapulmonary shunt (Qsp/Qt), and oxygen delivery (DO2) in posttraumatic adult respiratory distress syndrome (ARDS). All hypoxemic trauma patients admitted to the surgical intensive care unit (SICU) in 1989-1990 who received PEEP greater than 15 cm H2O were included. The PEEP was titrated to achieve an intrapulmonary shunt (Qsp/Qt) of approximately 0.20, and FIO2 was weaned to less than 0.50. Hemodynamic and pulmonary variables at four distinct intervals were recorded. Fifty-nine patients received PEEP greater than 15 cm H2O. Of these, 19 patients died of severe head injury or uncontrollable hemorrhage (16 within 48 hours). Forty (29 male, 11 female) were evaluated in detail. The PEEP levels ranged from 18-50 cm H2O with a mean of 27. PaO2/FIO2 ratios and Qsp/Qt improved as PEEP therapy was titrated. Cardiac index and oxygen delivery were maintained or improved throughout PEEP therapy by transfusion and fluid resuscitation, with a mean maximum positive fluid balance of 21.1 L and an average of 51 units of blood and blood products transfused per patients during their SICU stay. Twenty-nine (73%) had evidence of barotrauma, the majority being pneumothoraces clearly related to the initial trauma. Only three (7.5%) had evidence of barotrauma not related to trauma or line insertion. Eight of 40 patients (20%) died. Mean ISS and RTS for the entire group were 32 and 5.88, respectively. We conclude that titration of PEEP to achieve a Qsp/Qt of approximately 0.20 is an attainable goal. This was accomplished with minimal hemodynamic effects or barotrauma and a low mortality rate.
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Respiración con Presión Positiva , Síndrome de Dificultad Respiratoria/terapia , Heridas y Lesiones/complicaciones , Adolescente , Adulto , Anciano , Barotrauma/etiología , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Síndrome de Dificultad Respiratoria/etiología , Síndrome de Dificultad Respiratoria/mortalidad , Síndrome de Dificultad Respiratoria/fisiopatología , Estudios RetrospectivosRESUMEN
Cardiovascular (CV) responses to feeding before and after 15% blood volume hemorrhage (H) were studied in lightly anesthetized piglets less than or equal to 2-days and greater than 2-wk-old. Superior mesenteric (Mes) and renal (Ren) arterial flows (F) were registered by electromagnetic probes before and continuously for 2 h after milk feeding (26 ml/kg) by gavage. Postprandially, in piglets less than or equal to 2-days-old MesF tended to increase (maximum change, mean +/- SE, 16.0 +/- 4.7%) at 30 min, whereas Mes vascular resistance (R) significantly decreased at 30, 90, and 120 min (17.3 +/- 6.2%). In piglets greater than 2-wk-old, MesF significantly increased by 30 min, which lasted 120 min (37.7 +/- 11.7%); MesR decreased by 20.0 +/- 5.8% at 90-120 min. Compared with the less than or equal to 2 days olds, the older piglets demonstrated greater and more sustained postprandial MesF increase. After H, regional F and pulse pressure (PP) decreased, heart rate and R increased in both groups. After stabilization, feeding induced insignificant CV changes in less than or equal to 2-day-old piglets. In contrast, increased MesF (44 +/- 14.4%) and PP (24 +/- 8.5%) and decreased MesR (31 +/- 8.9%) were observed in the greater than 2-wk-olds. MesF changes differed significantly between the age groups. The Ren vascular bed showed no consistent response in both age groups. Thus Mes vascular responses to feeding with or without preceding H in developing piglets were age related.
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Envejecimiento/fisiología , Animales Recién Nacidos/fisiología , Alimentos , Hemorragia/fisiopatología , Arterias Mesentéricas/fisiopatología , Animales , Velocidad del Flujo Sanguíneo , Hemodinámica , Cinética , Arteria Renal/fisiopatología , Circulación Renal , Resistencia VascularRESUMEN
Cardiovascular responses to stimulation of cardiopulmonary receptors were evaluated in standard breed developing swine (1-2 days, 1-2 wk, and 2 mo of age) and sexually mature miniswine anesthetized with 0.25-0.50% halothane in O2. Cryptenamine, a mixture of veratrum viride alkaloids (VVA), was administered as right atrial or left ventricular bolus injections in doses of 5-20 micrograms/kg. In developing swine, mean aortic pressure (AoP) decreased after 10-20 micrograms/kg VVA in 1- to 2-wk olds and after 5-20 micrograms/kg VVA in 2-mo olds. Bradycardia was always elicited. Renal (Ren) and femoral (Fem) vasodilation occurred in the 1- to 2-wk-old and 2-mo-old groups after 5-20 micrograms/kg VVA. Mesenteric (Mes) vasodilation was elicited with 10-20 micrograms/kg VVA in the 1- to 2-wk-old group and with 5-20 micrograms/kg VVA in 2-mo olds. In the 1- to 2-day-old group, VVA did not significantly alter Ren, Fem, and Mes vascular resistance. In mature miniswine, 20 micrograms/kg VVA elicited decreases in AoP and heart rate that were similar in magnitude to responses obtained with only 5 micrograms/kg VVA in dogs. Cardiovascular responses to VVA were abolished after bilateral vagotomy but were not altered after denervation of the carotid sinuses. The results indicate postnatal maturation of the Bezold-Jarisch reflex in swine.
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Envejecimiento , Corazón/fisiología , Pulmón/fisiología , Células Receptoras Sensoriales/fisiología , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Presión Sanguínea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Frecuencia Cardíaca/efectos de los fármacos , Porcinos , Porcinos Enanos , Alcaloides de Veratrum/farmacologíaRESUMEN
We have developed a polyacrylamide gradient gel electrophoretic method to quantitate apo-, mono-, and diferric transferrin based upon differences in their molecular size. Purified transferrin saturated to different extents (3% to 98%) with iron showed proportions of the three forms as predicted from an approximately random distribution of iron between the two metal-binding sites. The iron distributions in sera of 14 normal individuals similarly correlated with the predicted values. In contrast, 22 of 43 patients with diseases associated with abnormalities in iron or transferrin metabolism had a disproportionate increase in monoferric transferrin. This abnormality occurred in seven of nine patients who had received bone marrow transplants, seven of 14 with chronic liver disease, and eight of nine menstruating women with probable iron deficiency anemia. Interestingly, 11 patients with malabsorption or chronic renal disease had normal iron distributions. The finding of abnormal distributions of iron on transferrin suggests that gradient gel analysis may be a useful tool for studying the physiologic mechanisms controlling iron utilization.
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Anemia Hipocrómica/sangre , Apoproteínas , Transferrina/análisis , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Hierro/sangre , Enfermedades Renales/sangre , Leucemia/sangre , Hepatopatías/sangre , Masculino , Trastornos Nutricionales/sangreRESUMEN
Recent evidence suggests that transferrin has immunoregulatory functions. In the nephrotic syndrome, excessive urinary losses can produce hypotransferrinemia. Whether low serum transferrin concentration in children with the nephrotic syndrome is related to their decreased immunoglobulin concentrations and to the decreased in vitro response of lymphocytes to a mitogen was studied. Twenty patients, 2 to 15 years of age, were studied. Fifteen patients had the nephrotic syndrome and 5 had other renal disorders. Of 13 patients with nephrotic syndrome in relapse, serum transferrin and gamma-globulin concentrations were decreased in 10 and 11 patients, respectively. Transferrin levels correlated with the concentrations of total protein (r = 0.87, P less than 0.001), albumin (r = 0.91, P less than 0.001), and gamma-globulin (r = 0.78, P less than 0.001). Urinary electrophoretic analyses suggested that hypogammaglobulinemia was not explained simply by urinary losses. In order to determine whether decreased serum transferrin concentrations might limit immunoglobulin synthesis, the effect of hypotransferrinemic sera on lymphocyte proliferation in vitro was tested. At low concentrations of serum, tritiated thymidine uptake was directly proportional to the serum transferrin concentration (r = 0.86, P less than 0.001 at 0.02% serum concentration). Addition of transferrin completely restored the ability of patients' sera to support lymphocyte proliferation. These results suggest that hypotransferrinemia might influence in vivo lymphocyte function and immunity in the nephrotic syndrome.
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Inmunoglobulinas/análisis , Activación de Linfocitos/efectos de los fármacos , Síndrome Nefrótico/sangre , Transferrina/análisis , Adolescente , Proteínas Sanguíneas/análisis , Niño , Preescolar , Concanavalina A/farmacología , Humanos , Hierro/sangre , Nefrosis Lipoidea/sangre , Transferrina/inmunología , gammaglobulinas/orinaRESUMEN
The induction of suppression by i.v. administered alloantigens in the murine host was analyzed as a model of the possible effects of blood transfusion on transplant survival. The results indicated that suppressor T cells (Ts) specific for minor histocompatibility alloantigens could be readily induced by the i.v. presentation of minor alloantigen-disparate spleen cells. In contrast, similar priming with cells differing solely at the H-2 major histocompatibility complex stimulated only positive T cell immunity, with no evidence of suppression. The induction of H-2 directed Ts activity could be accomplished only by i.v. priming with major plus minor incompatible donor cells, suggesting that suppressor cell recognition of minor alloantigens may have facilitated the generation of Ts against H-2-encoded major transplantation antigens. A role for minor histocompatibility antigens in the regulation of H-2-specific immunity at the effector level was also indicated. Ts induced by i.v. pretreatment with minor antigen-disparate donor cells not only suppressed the delayed-type hypersensitivity (DTH) response to the relevant minor alloantigens, but also inhibited DTH against unrelated H-2 alloantigens introduced during subsequent intradermal immunization. Suppression of H-2-directed T cell reactivity was specific in that the presence of the Ts-inducing minor alloantigens was also required and occurred only when the minor and unrelated major alloantigens were presented within the same inoculum, if not on the same cell surface. The capacity of Lyt-2+Ts or Ts-derived suppressive factors specific for one set of cell surface molecules to modulate responses to an unrelated group of surface antigens does not appear to represent a general phenomenon, because similar suppression of immunity to unrelated tumor-specific transplantation antigens by minor-specific Ts was not observed. These results are discussed with respect to the possible mechanism of H-2-directed suppression and the role of the I region in Ts recognition of antigen.