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Chemokines direct leukocytes to areas of inflammation or injury. In general, CC chemokines (MCP-1, MIP-1alpha, RANTES) are chemoattractants for mononuclear cells and CXC (CINC-1, MIP-2alpha) for polymorphonuclear cells (PMNs). Herein we describe an open chest model of pulmonary contusion (PC) in a rodent (rat) and have identified a possible role for CC and CXC chemokines in the pathogenesis of PC.Sprague-Dawley rats (350 g) underwent thoracotomy. The exposed lung was struck with a piston at 5.2 m/s (150 J/M2). Blood, bronchoalveolar lavage (BAL), and lung tissue were collected at 3 hours and 24 hours after injury. PaO2/FiO2 (P/F) ratio was calculated at 15-minute intervals for 3 hours after contusion. Serum was evaluated for cytokine and chemokine expression using ELISA. Cell count/differential was performed on BAL, and lung tissue was obtained for histologic analysis, protein expression and wet to dry weights. Data are reported as pg/mL +/- SE. Data were analyzed using Student's t test to identify significant differences (por = 0.05 significant) between sham and injured animals.Piston impact caused PC based upon morphologic and histologic criteria. BAL cell count and lung wet to dry weights were increased and P/F ratio was decreased after PC. Systemic levels of IL-ra, MCP-1, and the CXC chemokines MIP-2alpha and CINC-1 were significantly elevated at 3 hours when sham and injured animals were compared. All chemokines were found to be significantly elevated at 24 hours, consistent with the early PMN and subsequent mononuclear infiltration observed in the contused lung. Pulmonary expression of TNF-alpha, IL-1beta, CINC-1, MIP-2alpha, ICAM-1, and elastase were increased and activated systemic neutrophils showed increased CD-11b.A model of PC is described in which innate inflammation is activated locally and systemically. Systemic levels of CC and CXC chemokines are increased after PC. This correlates with elevated PMN CD-11b expression, enhanced pulmonary ICAM-1 expression, and mononuclear and PMN infiltration into the lung and alveolar space. Elevated levels of CC and CXC chemokines are seen after PC and may be involved in the lung's inflammatory response to injury.

INTRODUCTION: Helmet laws remain controversial. Opponents believe negative findings are a result of biased statistical analyses that fail to account for the impact of alcohol and drugs. In this study, we evaluated the effect that helmet use had upon injury severity, outcome controlling for alcohol or drug use, resource utilization, and financial burden using the National Trauma Data Bank (NTDB). METHODS:: Two groups of patients, helmeted and non-helmeted motorcyclists, were identified using the NTDB over an 8-year period. Group differences were compared using nonparametric Wilcoxon tests for continuous variables and Fisher's exact test for dichotomous outcomes. To evaluate the effect that alcohol or drug use had on mortality, logistic regression models were created. RESULTS:: A total of 9,769 patients were identified by the NTDB of which 6756 (69.2%) were helmeted and 3013 (30.8%) were non-helmeted. Helmet use was associated with lower injury severity, mortality, and resource utilization. Non-helmeted motorcyclists accrued greater hospital charges and were significantly less likely to have health insurance. When controlling for alcohol or drug use, mortality continued to be significantly associated with non-helmet use. CONCLUSION:: Non-helmeted motorcyclists have worse outcomes than their helmeted counterparts independent of the use of alcohol or drugs. Furthermore, they monopolize more hospital resources, incur higher hospital charges, and as non-helmeted motorcyclists frequently do not have insurance, reimbursement in this group of patients is poor. Thus, the burden of caring for these patients is transmitted to society as a whole.

Recent randomized prospective data suggest that early hyperglycemia is associated with excess mortality in critically ill patients, and tight glucose control leads to improved outcome. This concept has not been carefully examined in trauma patients, and the relationship of early hyperglycemia to mortality from sepsis in this population is unclear. The objective of this study was to determine the relationship different levels of early blood glucose elevation to outcome in a trauma ICU population.The records of all patients admitted to the ICU over a 2-year period at a Level I trauma center were reviewed for age, injury severity scores (ISS), admission Glasgow Coma Scale (GCS) score, base deficit (BD), blood glucose, and mortality. Three possible cutoffs in defining hyperglycemia were examined (glucoseor =110 mg/dL,or =150 mg/dL,or =200 mg/dL) in relation to infection and mortality. Early hyperglycemia was defined as elevated blood glucose on hospital days 1 or 2. Those with diabetes mellitus were excluded.From 1/00-12/01, 516 eligible patients were admitted to the ICU after injury. Early hyperglycemia occurred in 483 at theor =110 mg/dL level, 311 at theor =150 mg/dL level, and 90 patients at theor =200 mg/dL level. Univariate logistic regression demonstrated a significant relationship between ISS and subsequent infection(p = 0.02) and a trend toward such a relationship in GCS score, glucoseor =150 mg/dL, and glucoseor =200 mg/dL (p = 0.06, 0.12, and 0.06). A similar analysis for the relationship of these variables to eventual mortality showed a significant correlation with all examined variables except glucoseor =110 mg/dL. Multiple logistic regression to control for the effect of age, ISS, GCS score, and BD found early glucoseor =200 mg/dL to be an independent predictor of both infection and mortality while no such relationship was found withor = 110 mg/dL oror =150 mg/dL.Early hyperglycemia as defined by glucoseor =200 mg/dL is associated with significantly higher infection and mortality rates in trauma patients independent of injury characteristics. This was not true at the cutoffs ofor =110 mg/dL oror =150 mg/dL. These data support the need for a prospective analysis of tight glucose control, keeping serum glucose200 mg/dL in critically ill trauma patients. However, aggressive maintenance of levels110 mg/dL as reported by others may not be necessary.

Background: Recent laboratory studies have demonstrated that immune responses differ between male and female rodents, and some clinical studies have suggested gender differences regarding incidence and mortality from sepsis. The differences appear because of both deleterious testosterone and beneficial estrogen effects; clinical trials of testosterone blockage and/or estrogen administration for male subjects have been suggested. We evaluated the effect of gender on various outcomes in trauma patients. Methods: Trauma patients over a 52-month period were identified from the trauma registry. Early deaths were excluded. Outcomes included mortality, pneumonia (≥ 10 5 colony-forming units/mL in bronchoalveolar lavage effluent), acute respiratory distress syndrome, bacteremia, ventilator days, and intensive care unit and hospital length of stay. Patients were stratified by injury mechanism, gender, age (assuming women S 40 were premenopausal and those >50 were postmenopausal), and injury severity. Results: There were 18,133 patients identified, and 544 were excluded because of early death. There were 12,756 (73%) men and 4,833 (27%) women. There were no outcome differences after penetrating injury with respect to gender and age group. There was a survival advantage for women ≤ 40 in the Injury Severity Score 16 to 24 group, but these patients had statistically less severe injury. Overall, men tended to have more infectious complications, but women had lower survival in the face of infection. Logistic regression did not identify gender as an independent predictor of mortality. Conclusion: Although there was a survival advantage for women in subgroup analysis, there was no overall difference in mortality. Women with pneumonia, however, had a higher mortality than men. Further understanding of potential mechanisms is necessary before hormonal manipulation studies.

Patients with blunt aortic injury (BAI) often have concomitant liver or spleen (L/S) injuries. With increasing use of cardiopulmonary bypass with heparinization in repair of BAI, many advocate operative management of the L/S injury before aortic repair to eliminate risk of hemorrhage. We evaluated the safety of nonoperative management (NOM) of blunt L/S injuries in patients undergoing acute BAI repair with bypass.All patients admitted over a 6-year period with BAI were identified from the registry of our Level I trauma center. Patients with isolated L/S injuries without BAI admitted over the same period served as controls. Groups were compared with regard to demographics, injury characteristics, hospital course, and mortality.Eighty-four patients were diagnosed with BAI from 1994 to 2000; 28 (33%) also had blunt abdominal trauma. Three patients with severe brain injury did not undergo BAI repair, and five required laparotomy before BAI repair for other intra-abdominal injuries (two for hemodynamic instability with splenic injury, and three for concomitant bowel injury). Therefore, 20 of 28 (71.4%) BAI patients with grade I or II L/S injury (Aorta L/S group) underwent planned NOM. All BAIs were repaired using partial bypass with full heparinization. These 20 patients are compared with 894 patients with grade I or II L/S injuries with no BAI (L/S group) over the same time period. There was no difference in the nonoperative failure rate of the Aorta L/S group versus the L/S group (0% vs. 1.7%). Both groups had similar complication rates. The Aorta L/S group was also compared with 56 BAIs without solid organ injury (Aorta group). Although the Aorta L/S group was more severely injured than the Aorta group (Injury Severity Score of 35.3 vs. 26.8,0.0001), transfusion rates (5.7 U of packed red blood cells vs. 8.0 U of packed red blood cells, p = NS), hospital days (17.9 vs. 19.1, p = NS) and mortality (10% vs. 9%, p = NS) were similar.NOM of patients with grade I or II L/S injury who undergo systemic anticoagulation with heparin for repair of BAI is safe and associated with transfusion rates similar to BAI alone. Patients with low-grade liver or spleen injuries do not require laparotomy before BAI repair using partial bypass.

Background: During the past decade, nonoperative management (NOM) of hemodynamically stable blunt trauma patients with liver (L) or spleen (S) injury has become the standard of care. This trend has led to concerns over missed associated intra-abdominal injuries with concomitant morbidity. To better understand the incidence and risk of missed injury, patterns of associated intra-abdominal injury were examined in all patients with blunt liver and spleen injuries, and missed injuries were reviewed in patients undergoing NOM. Methods: Patients were identified from the registry of a Level I trauma center over a 3-year period. Records were reviewed for demographics, injury characteristics, and associated injuries. Indications for primary operation were hemodynamic instability or significant associated intra-abdominal injury. Missed injury was defined as unsuspected intra-abdominal injury requiring laparotomy in patients otherwise undergoing NOM for liver or spleen injury. Results: Eight hundred three patients (338 in the L group, 345 in the S group, and 120 in the L + S group) were treated between December 1995 and December 1998. Rates of planned NOM were 89% (L group), 78% (S group), and 75% (L + S group). On examination of all patients with blunt liver or spleen injuries, the incidence of associated intra-abdominal injury was higher in the L group at 5% as compared with 1.7% in the S group (p = 0.02). The associated intra-abdominal injury rate in the L + S group was similar to the L group at 4.2%. Although in the L and S groups, rates of diaphragm (0.5% vs. 1%, p = 0.45) and intra-abdominal bladder injury (0.3% vs. 0.3%, p = 0.99) were similar, bowel injury was more common in the L group (11% vs. 0%, p = 0.0004), as was pancreatic injury (7% vs. 0%, p = 0.007). In NOM patients, missed injury occurred in seven (2.3%) L patients versus zero S patients (p = 0.012). No L + S patient had unexpected injuries. Missed injuries included two small bowel, three diaphragm, one pancreas, and one mesenteric tear. Conclusion: Damage to the pancreas and bowel is significantly associated with liver as opposed to spleen injuries. Actual missed intra-abdominal injury with NOM mirrors this pattern, occurring more often with liver than with spleen injuries. However, the overall incidence of missed injury is quite low, and should not influence decisions concerning eligibility for NOM. We speculate that the greater amount and/or different vector of energy transfer needed to injure the liver versus the spleen accounts for the greater rate of associated injuries to the pancreas/small bowel.

Background: The pathophysiology of pulmonary contusion (PC) is poorly understood, and only minimal advances have been made in management of this entity over the past 20 years. Improvement in understanding of PC has been hindered by the fact that there has been no accurate way to quantitate the amount of pulmonary injury. With this project, we examine a method of accurately measuring degree of PC by quantifying contusion volume relative to pulmonary function and outcome. Methods: Patients with PC from isolated chest trauma who had admission chest computed tomographic scan were identified from the registry of a Level I trauma center over a 1.5-year period. Subsequently, prospective data on all patients admitted to the intensive care unit with PC during a 5-month period were collected and added to the retrospective database. Using computer-generated three-dimensional reconstruction from admission chest computed tomographic scan, contusion volume was measured and expressed as a percentage of total lung volume. Admission pulmonary function variables (Pao 2 /FiO 2 , static compliance), injury descriptors (chest Abbreviated Injury Score, Injury Severity Score, injury distribution), and indicators of degree of shock (admission systolic blood pressure, admission base deficit) were documented. Outcomes included maximum positive end-expiratory pressure, ventilator days, pneumonia, and acute respiratory distress syndrome (ARDS). Results: Forty-nine patients with PC (35 bilateral) were identified. The average severity of contusion was 18% (range, 5-55%). Patients were classified using contusion volume as severe PC (≥20%, n = 17) and moderate PC (

Objective: Maintaining left ventricular power output (LVP) > 320 mm Hg.L/ min/m 2 during resuscitation has been retrospectively associated with faster resolution of acidosis and survival after posttraumatic shock. The purpose of this prospective study was to evaluate the effects of maintaining LVP above this threshold during resuscitation on base deficit clearance, organ failure, and survival. Methods: This was a study of a consecutive series of critically injured patients (PWR) monitored with a pulmonary artery catheter during initial resuscitation. LVP, calculated as cardiac index.(mean arterial pressure-central venous pressure), was maintained >320 mm Hg.L/min/m 2 via a predefined protocol by using ventricular pressure-volume diagrams. Outcome was assessed by base deficit clearance (

Background: The gastric intramucosal pH (pHi) and gastric mucosal-arterial CO 2 gap (GAP) estimate visceral perfusion and predict outcome. Threshold values of these variables for use during resuscitation, however, remain poorly defined. The purpose of this study was to develop clinically derived cutoffs for both pHi and GAP for predicting death and multiple organ failure (MOF) in trauma patients. Methods: This was a cohort study of 114 consecutive trauma patients who had pHi determined at 24 hours after intensive care unit admission. The corresponding GAP for each of these values of pHi was obtained through chart review. Receiver operating characteristic curves were constructed for both pHi and GAP with respect to death and MOF. These curves were used to determine the value of each variable that maximized the sum of sensitivity and specificity in predicting outcome. X 2 tests and odds ratios were used to determine if significant differences in outcome occurred above and below these cutoff values. Results: Of 114 patients who had pHi determined at 24 hours after admission, 108 had corresponding GAP values available. The values of pHi and GAP that maximized sensitivity and specificity were 7.25 and 18 mm Hg, respectively. The odds ratio for pHi versus death was 4.6 and for pHi versus MOF was 4.3. The odds ratios for GAP versus death and MOF were 2.9 and 3.3, respectively. Conclusion: In trauma patients, the ability to predict death and MOF is maximized at values of pHi less than 7.25 and GAP greater than 18 mm Hg. These values represent clinically derived cutoffs that should be useful for evaluating the adequacy of intestinal perfusion during resuscitation.

An association between cervical fractures and thoracolumbar fractures after blunt trauma has long been assumed, but not adequately demonstrated. We sought to determine the actual association between these injuries in a large nationwide data set.The National Trauma Databank (NTDB) was queried for victims of blunt vehicular trauma with at least minimal injury. An odds ratio was calculated for the association between cervical spine fractures and thoracolumbar fractures.Overall 190,183 NTDB patient records met the criteria of a motor vehicle crash with more than minimal injury. Of these 7.51% (14,292) had cervical spine fractures, 4.73% (8,996) had thoracic spine fractures, 5.93% (11,280) had lumbar spine fractures, and 9.79% (18,623) had either thoracic or lumbar fractures. Of patients with a cervical spine fracture, 13.06% (2,433) also had a thoracic or lumbar fracture, whereas among patients without cervical spine fracture only 6.91% (11,859) had a thoracolumbar fracture. The odds ratio (OR) for a thoracolumbar fracture in the presence of a cervical spine fracture was 2.02 (p0.0001) (95% confidence interval 1.9318-2.1201).These data confirm a strong association between cervical spine fractures and thoracolumbar fractures after blunt vehicular trauma, and support the practice of imaging the complete spine when a cervical fracture is identified.