Research Forum Abstracts were derived from a sample of 20 R-waves at 0 and ÿ60mmHg levels of LBNP during the last minute of each stage. Results: The use of LBNP resulted in a significant reduction in central blood volume as indicated by decreases in SV from 125 G 9 to 43 G 6 ml (p\.001) and SBP from 129 G 3 to 111 G 6 mmHg (p=.005) and elevation in HR from 57 G 3 to 89 G 5 (p\.001). Despite significant reduction in central blood volume, R-wave amplitude at -60 mmHg LBNP (0.95G0.15) did not differ (P = 0.26) from baseline (0.94 G 0.15). Conclusion: Significant reduction of central blood volume by LBNP in humans is not associated with variations in R-wave amplitude. Our data do not support the use of the R-wave amplitude as an early predictor of hypovolemia.
chest injuries were 17.3 (95% CI 6.9-43.6). The median systolic Bp and GCS of casualties who died vs. those that survived were 62 mmHg vs. 113 mmHg and 3 vs. 15 respectively. The median Abbreviated Injury Scale (AIS) of the head and thoracic region of casualties who died vs. those that survived were 3 vs. 0 and 4 vs. 0 respectively. We found that mortality was not associated with gender and only weakly associated with older age (P=0.49). Conclusions: In our study population, aggressive management of hypotension, coma and associated injuries would likely contribute to improving survival.
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Henry MC, McCormack JE, Huang EC, Thode HC Jr, Stony Brook University Hospital, Stony Brook, NY; Stony Brook University, Stony Brook, NY
Pediatric Head Injury in an Urban Level 1 ED
Korn CS, Hollinger M, Henderson SO, Keck School of Medicine of the University of Southern California, Los Angeles, CA
Study Objectives: To described the mechanism of injury, CT findings and disposition in a cohort of pediatric trauma patients that sustained significant head injury. Methods: This was a retrospective chart review of all pediatric patients (newborn to 14 years of age) presenting with trauma to the emergency department of an urban Level I trauma center. Cases were collected over an eight year period (January 1997 to December 2004). Those patients that suffered significant head injury were reviewed for mechanism of injury, age, diagnosis or injury and disposition from the emergency department. Results: For the time period studies there were 3110 pediatric patients presenting with trauma, 165 of which sustained ‘‘critical head trauma’’. The number of individuals decreased as the age increased - 30% were between 0-3 years of age, 21% were between 4 and 6 years of age, 16% were between 7 and 9 years of age, 18% were between 10 and 12 years of age and 13% were 13 years or older. The most common finding on CT scan was intracerebral bleeding (34%), followed by subdural hematoma (24%), Epidural hematoma (21%), Subarachnoid hemorrhage (18%) and massive/diffuse cerebral edema (8%). The mechanism of injury was most often a fall either from ground level or from a height (35%), an auto versus pedestrian or bicycle (33%), a gunshot wound (13%) or a motor vehicle accident (6%). The majority of patients were admitted (86%) with another 13% going directly to the operating room from the emergency department. There was only one patient who expired while in the ED. Conclusion: In this cohort of severely head-injured patients, more than half were under the age of 6 years and the most common mechanisms of injury were falls and automobile versus bicycle/pedestrian. Although the majority of patients were admitted for observation, 13% of patients went directly to the OR.
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The Epidemiology and Mortality of Pelvic Fractures
Phua D, Seow E, Tan Tock Seng Hospital, Singapore, Singapore
Objective: To look into the epidemiology and factors associated with mortality amongst adult trauma casualties with pelvic fracture in an Asian urban city. Method: Retrospective analysis using data captured in a comprehensive trauma database of all trauma casualties with pelvic fractures admitted to a large adult urban hospital of about 1200 beds. Data from April 2001 to December 2004 was analysed. Non-parametric tests were used in epidemiological analysis and multivariate analysis was used to study the factors associated with mortality. Results: There were 178 trauma casualties with pelvic fractures. Their age ranged from 13 to 86 years old (mean 38.4). The majority of these casualties were in the prime of their life, 70.8% were from the age group 20-49 years old. There was a high proportion of male, 62.9% compared to 37.1% female. Motor vehicular accidents and fall from height were the most common mechanisms of injury, accounting for 51.7% and 44.9% of the casualties respectively. Seventy percent of casualties of motor vehicular accidents were either pedestrian or motorcyclist. The mean Injury Severity Score (ISS) was 28 and the mean Revised Trauma Score (RTS) was 5.9 In our study group, 37.1% of the casualties died from their injuries. The grade of the pelvic fracture did not impact on mortality. However, mortality was significantly associated with initial hypotension (systolic Bp\90), coma (CGS\9) and associated head and chest injuries. The odds of dying in patients with initial hypotension were 10.5 (95% CI 5.1-21.4, P\0.001) and with coma were 19.1 (95% CI 8.4-43.5, P\0.001). The odds of dying in patients with head injuries were 7.4 (95% CI 3.7-14.7) and with
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Temporal Arrival Patterns and Subspecialty Needs of Trauma Patients Requiring Emergency Operating Room Operative Intervention
Objectives: Trauma centers require standby personnel and on-call specialists for emergency response. Knowledge of time and day of arrival of patients requiring surgery helps predict resource needs. Methods: Retrospective descriptive study; emergency department (ED) patients meeting New York State criteria for inclusion in the regional trauma registry and who were admitted to the operating room (OR) directly from the ED were identified from a regional trauma registry covering a population of 1.4 million for 1999-2003. Times of arrival at ED and sent directly to the OR were analyzed by hour of day, day of week, hospital designation, service, injury type and other factors. Results: 7,654 patients met state criteria for inclusion in the registry. Of these, 1,509 (20 %) were admitted directly from the ED to the OR. Most frequent specialty surgical services were orthopedic (53%), abdominal (28%) and neurosurgical (16%), with some patients requiring more than one service. Overall patient input to ED peaked at 2-6 PM with 26% of patients arriving in that 4-hour period. OR admissions peaked with 27% of patients from 7-11 PM. Patient arrival and OR admission patterns were similar for trauma centers vs community hospitals. Weekday and weekend arrival and admission patterns by service were similar except for weekend abdominal surgery which required more uniform service throughout the day. Daily patient load was highest on Saturday and Sunday. 39% of abdominal, 19% of neurosurgical and 9% of orthopedic patients had an ED LOS \ 2 hours, which was similar for weekends and weekdays. Conclusions: Admission of patients requiring emergent operative service was highest in the afternoon/evening and on weekends and was similar across a variety of factors. Orthopedic and neurosurgical services constituted more than half of operative needs.
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Platelets Induce T-Helper Cell Apoptosis in a Murine Model of Early Sepsis
Freishtat RJ, Sachdeva R, Mitchell LW, Children’s National Medical Center, Washington, DC; George Washington University School of Medicine, Washington, DC
Study Objectives: Emegency department (ED) early goal-directed therapy for sepsis aims to restore hemodynamics and address disseminated intravascular coagulation (DIC), which in part is triggered by T-helper cell (Th) apoptosis. Th apoptosis is induced by platelets in cardiovascular disease but the analagous interaction in sepsis is poorly understood. We aimed to identify platelet mechanisms of Th apoptosis induction in a model of early sepsis mimicking the likely period of ED presentation. Methods: Seven to nine week-old BALB/c mice were bled at t=0, 24, and 48h after intraperitoneal endotoxin. Platelets and Th1 cells were separated from whole blood. mRNA was isolated, amplified, and pooled according to time point and sepsis severity, and run on cRNA microarrays. ANOVA analysis generated a list of genes for each cell type with significant changes in expression over time. Results: All mice developed signs of sepsis. Platelet mRNAs for potent inducers of apoptosis were up-regulated: Granzymes A (Gzma)(Relative expression t0=1, t24=69, t48=142; p=0.004) and B (Gzmb) (1, 9, 18; p=0.003). Th1 cells showed upregulation of self-apoptotic transcripts [CD27-binding protein (Siva) (1, 11, 3; p=0.01) and Interferon- (IFN-g) (1, 6, 3; p=0.03)] and anti-apoptotic transcripts [B-cell leukemia/lymphoma related protein-2 (Bcl-2) (1, 10, 6; p=0.03) and Myeloid cell leukemia sequence-1 (Mcl-1) (1, 25, 44; p=0.0004)]. Conclusion: Granzyme up-regulation suggests that platelets are active inducers of Th apoptosis during sepsis, potentially worsening DIC. Th1 expression of Bcl-2 and Siva, which are known to balance each other, reflect internal mechanisms attempting to control cell death. Ongoing studies on these proteins will lead to a better understanding of sepsis as it presents in the ED and potentially identify targets for future early goal-directed therapy pathways.
Annals of Emergency Medicine S67