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J Wayne Meredith

Publications and source records attributed to J Wayne Meredith.

At least 19 recordsLinked to original sources
PubMed2006

National nosocomial infection surveillance system: from benchmark to bedside in trauma patients.

INTRODUCTION: Ventilator-associated pneumonia (VAP) is an important cause of morbidity and mortality in the injured patient. Identification of those with VAP is important both in immediate clinical decision making as well as for the epidemiologic evaluation of the disease and benchmarking of rates across institutions with variable practice patterns. Despite this, controversy exists over the optimal method of VAP diagnosis. Many centers currently use invasive culture methods such as bronchoalveolar lavage (BAL) for diagnosis. Another diagnostic method, and the most common epidemiologic tool used to track VAP, is the definition employed by the National Nosocomial Infections Surveillance (NNIS) system. This relies on a combination of clinical and culture data. Our goal was to evaluate the accuracy of the NNIS definition as compared with BAL diagnosis in trauma patients. METHODS: Records of all ventilated patients admitted to the trauma intensive care unit at a Level I center who were evaluated for the presence of pneumonia over a 2.5-year period were reviewed. VAP diagnosis was established if > or =10 cfu/mL were cultured on BAL. VAP rates and time of onset were compared with the hospital infection control database, which defines VAP by NNIS criteria. Assuming BAL to be correct, sensitivity, specificity, and positive and negative predictive values were calculated for NNIS VAP. RESULTS: From September 1, 2001, through December 31, 2003, 292 patients underwent BAL for suspected pneumonia. The pneumonia rate in this group was 34 per 1,000 ventilator days. The NNIS definition showed excellent overall agreement, with a rate of 36 per 1,000 ventilator days. The use of the NNIS definition for bedside decision making, however, is less accurate. Sensitivity and positive predictive value were reasonably good (84% and 83%, respectively), whereas specificity and negative predictive value suffer (69% and 69%, respectively). Most importantly, the use of NNIS would have led to no treatment in 16% of patients diagnosed with VAP by BAL. CONCLUSIONS: Compared with strict bacteriologic criteria for VAP, the NNIS definition has good overall agreement and seems to have utility as an epidemiologic benchmarking tool in trauma patients. However, the NNIS definition has less utility as a bedside decision-making tool in this population, leading to under-treatment in a significant number of patients.

Adult↗
PubMed2006

A practical application of practice-based learning: development of an algorithm for empiric antibiotic coverage in ventilator-associated pneumonia.

BACKGROUND: Development of practice-based learning (PBL) is one of the core competencies required for resident education by the Accreditation Council for Graduate Medical Education, and specialty organizations including the American College of Surgeons have formed task forces to understand and disseminate information on this important concept. However, translating this concept into daily practice may be difficult. Our goal was to describe the successful application of PBL to patient care improvement with development of an algorithm for the empiric therapy of ventilator-associated pneumonia (VAP). METHODS: The algorithm development occurred in two phases. In phase 1, the microbiology and timing of VAP as diagnosed by bronchoalveolar lavage was reviewed over a 2-year period to allow for recognition of patterns of infection. In phase 2, based on these data, an algorithm for empiric antibiotic coverage that would ensure that the large majority of patients with VAP received adequate initial empiric therapy was developed and put into practice. The period of algorithm use was then examined to determine rate of adequate coverage and outcome. RESULTS: : In Phase 1, from January 1, 2000 to December 31 2001, 110 patients were diagnosed with VAP. Analysis of microbiology revealed a sharp increase in the recovery of nosocomial pathogens on postinjury day 7 (19% < day 7 versus 47% > or = day 7, p = 0.003). Adequate initial antibiotic coverage was seen in 74%. In Phase 2, an algorithm employing ampicillin- sulbactam for coverage of community- acquired pathogens before day 7 and cefipime for nosocomial coverage > or =day 7 was then employed from January 1, 2002 to December 31, 2003. Evaluation of 186 VAP cases during this interval revealed a similar distribution of nosocomial cases (13% < day 7 versus 64% > or = day 7, p < 0.0001). Empiric antibiotic therapy was adequate in 82% of cases or =day 7: overall accuracy improved to 83% (p = 0.05). Mortality from phase 1 to phase 2 trended toward a decrease (21% versus 13%, p = 0.1). CONCLUSIONS: Application of the concept of PBL allowed for identification of local patterns of infection and development of an institution specific treatment algorithm that resulted in >80% adequate initial empiric coverage for VAP with a trend toward decreased mortality. PBL allows for alteration in practice based on local patterns and outcomes and has the potential to improve patient care.

Algorithms↗
PubMed2006

Incorporating recent advances to make the TRISS approach universally available.

BACKGROUND: The Trauma and Injury Severity Score (TRISS), used to garner predictions of survival from the Injury Severity Score (ISS), the Revised Trauma Score (RTS, for physiologic reserve), and age is difficult for many trauma facilities to compute because it requires 8 to 10 variables and ISS depends on the specialized Abbreviated Injury Scale (AIS) scale rather than the International Classification of Diseases scale (ICD-9). It has been shown that metrics describing a patient's worst injury (WORSTSRR) are a powerful predictor of survival (regardless of coding type, AIS versus ICD-9) and that the Glasgow Coma Scale (GCS) motor component contains the majority of the information found in the full GCS score. This study hypothesized that the TRISS approach could be made more predictive and efficient with fewer variables by incorporating these advances. METHODS: A total of 310,958 patients with nonmissing TRISS variables were subset from the National Trauma Data Bank (NTDB). Logistic regression was used to model mortality as a function of anatomic, physiologic and age variables. A traditional TRISS model was computed (with NTDB-derived coefficients) that uses ISS, RTS, age index, and mechanism to predict survival. Four smaller three- or four-variable models employed the ICD-9 WORSTSRR, the GCS motor component, and age (both continuously and dichotomously). Two of the four models also use mechanism. These models were compared using the concordance index (c-index, a measure of model discrimination) and the pseudo-R statistic (estimates proportion of variance explained). RESULTS: Each experimental model (two models with 3 variables and two models with 4 variables) have superior discrimination and explain more variance than the traditional TRISS model that employs 8-10 variables. CONCLUSIONS: Recent advances in anatomic and physiologic scoring markedly simplify TRISS-type models at no cost to prediction. This approach uses routinely available data, requires up to seven fewer terms, and predicts at least as well as the original TRISS. These findings could increase the availability of accurate trauma scoring tools to smaller trauma facilities.

Abbreviated Injury Scale↗
PubMed2006

Validation of stroke work and ventricular arterial coupling as markers of cardiovascular performance during resuscitation.

BACKGROUND: Resuscitation regimens based on stroke work index (SWI) and ventricular-arterial coupling (VAC) are controversial. The Signal Interpretation and Monitoring (SIMON) system continuously collects and stores physiologic intensive care unit (ICU) bedside data at 3- to 5-second intervals. The purpose of this study was to demonstrate the capabilities of a completely automated data management system by further evaluating SWI-based resuscitation. METHODS: This study was a retrospective review of all severely injured patients requiring a pulmonary artery catheter (PAC) for acute postinjury resuscitation. Patients with a severe head injury were excluded. Hemodynamic (HD) data (21 million datapoints) were densely acquired and archived by SIMON. Mean values of HD variables were compared between survivors and nonsurvivors. Receiver operator characteristic (ROC) curves were constructed for HD variables. Threshold values which maximized sensitivity and specificity were determined. RESULTS: Eighty-eight patients over a 19-month time period met criteria and were included in the analysis. SWI was significantly greater in survivors versus nonsurvivors (4421 +/- 1278 versus 3163 +/- 1066 mm Hg . mL/m, p = 0.0008). VAC was quantified by the ratio (RATIO) of afterload (Ea) to contractility (Ees). RATIO (Ea/Ees) in survivors was significantly better than in nonsurvivors (1.9 +/- 1.1 vs. 2.9 +/- 1.0, p = 0.002). ROC curves identified threshold values of 3250 mm Hg x mL/m for SWI and 2.1 for RATIO (AUC = 0.78 and 0.82, respectively). CONCLUSION: Previous work demonstrating the use of SWI and VAC as resuscitation guidelines was supported through the use of a powerful ICU data management system (SIMON). The emergence of these "new vital signs" may change the way injured patients are evaluated and resuscitated in the ICU.

Adult↗
PubMed2006

The pathogenesis of pulmonary contusion: an open chest model in the rat.

BACKGROUND: 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. METHODS: 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 (p < or = 0.05 significant) between sham and injured animals. RESULTS: 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. CONCLUSION: 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.

Animals↗
PubMed2005

Injury-associated hypothermia: an analysis of the 2004 National Trauma Data Bank.

Severe injury and shock are frequently associated with abnormalities in patient body temperature. Substantial increases in mortality have been associated with profound hypothermia, especially below 35 degrees C. The purpose of this study was to further characterize the impact of hypothermia in a large dataset of trauma patients. This study was a retrospective analysis of the 2004 version of the National Trauma Data Bank (NTDB), which contains approximately 1.1 million patients from over 400 trauma centers. Admission temperature was analyzed with respect to mortality, injury severity score (ISS), base deficit (BD), Glasgow Coma Score (GCS), and hospital outcomes. The NTDB contained 701,491 patients with temperatures recorded upon trauma center admission. Of these, 11,026 patients had admission temperatures <35 degrees C, and 802 had temperatures <32 degrees C. Comparison of core temperature versus mortality revealed that as temperature decreased, the mortality rate increased, reaching approximately 39% at 32 degrees C, and remained constant at lower temperatures. Surprisingly, 477 patients (59.5%) survived with temperatures <32 degrees C. Similarly, BD increased as hypothermia worsened until body temperature reached 31 degrees C, below which there was little further increase. Patients with admission temperatures less than 35 degrees C had significantly greater mortality (25.5% vs. 3.0%, P < 0.001) and BD (7.8 vs. 3.7, P < 0.001) when compared with patients with temperatures >or=35 degrees C. In survivors, average ventilator days and intensive care unit (ICU) days were 14.4 and 12.8, respectively, for patients with temperatures <35 degrees C as opposed to more normothermic patients who demonstrated an average of 9.5 ventilator days and 9.1 ICU days (P < 0.001). When grouped by individual ISS, BD level, and GCS motor score, mortality was significantly greater when admission temperature was below 35 degrees C (ISS mean difference = 11.4%, BD mean difference = 22.8%, and GCS motor mean difference = 9.85%). Logistic regression revealed that hypothermia remains an independent determinant of mortality after correction for confounding variables (odds ratio = 1.54, 95% confidence interval 1.40-1.71). Admission hypothermia is associated with greater mortality, increased injury severity, more profound acidosis, and prolonged ICU/ventilator courses. However, although mortality at <32 degrees C is high, patients with temperatures this low do survive. As temperatures drop below 32 degrees C, mortality rates remain constant, which may indicate a threshold below which physiologic mechanisms are unable to correct body temperature regardless of injury severity. Although shock severity is highly indicative of outcome, hypothermia independently contributes to the substantial mortality associated with severe injury.

Adolescent↗
PubMed2005

Prospective comparison of bronchoalveolar lavage and quantitative deep tracheal aspirate in the diagnosis of ventilator associated pneumonia.

BACKGROUND: Ventilator associated pneumonia (VAP) is common in trauma patients, and accurate diagnosis of VAP may improve survival. With the risk of development of bacterial resistance, we also strive to minimize the use of unnecessary antibiotics. Recent studies suggest that quantitative deep endotracheal aspirate (QDEA) is adequate in VAP diagnosis. We currently use bronchoalveolar lavage (BAL) diagnosis. The purpose of this study was to examine the accuracy of QDEA as compared with BAL in diagnosing VAP in trauma patients. METHODS: We prospectively compared the results of BAL and QDEA in intubated patients suspected of having VAP during an 8-month period. Indication for BAL was pulmonary infiltrate, systemic inflammatory response syndrome, and C-reactive protein >17 mg/dL at > or =48 hours after admission. Study patients underwent QDEA immediately before BAL, and quantitative cultures were compared for both specimens. The techniques differ in that QDEA involves the direct culture of sputum suctioned from the distal trachea, whereas BAL involves lavage of the bronchoalveolar tree with sterile saline, which is then cultured. VAP was diagnosed on BAL if > or =10(5) cfu/mL was present on culture. The ability of QDEA to diagnose pneumonia was examined at cutoffs of > or =10(5) cfu/mL and > or =10(4) cfu/mL, as compared with BAL at > or =10(5). RESULTS: Sixty-one patients underwent BAL during this period, and 39 of these underwent both BAL and QDEA for the study. Of the 39 studied patients between March 16, 2002, and November 4, 2002, 20 (51%) were found to have VAP by BAL (> or =10(5) cfu/mL). Using this cutoff for QDEA, 18 of 20 (90%) would have been correctly diagnosed. Using > or =10 cfu/mL for QDEA, the rate of correct diagnosis would increase to 19 of 20 (95%). However, of the 19 who did not have pneumonia according to BAL, 6 (31%) would have been incorrectly diagnosed with VAP using the QDEA cutoff of > or =10(5) cfu/mL. A QDEA cutoff of > or =10 (4) cfu/mL would result in the even higher false-positive rate of 8 of 19 patients (42%). CONCLUSION: Whereas most patients with pneumonia by BAL would have been diagnosed by QDEA, use of QDEA in treatment decisions would have led to needless antibiotic administration in 31% of VAP-negative patients at a cutoff of > or =10(5) cfu/mL and 42% at > or =10(4) cfu/mL. The use of QDEA in VAP diagnosis is limited because of the rate of over-diagnosis. With the increasing problems associated with excess antibiotic use, we believe these results support the use of BAL over QDEA in the diagnosis of VAP in the ventilated trauma patient.

Bronchoalveolar Lavage Fluid↗
PubMed2005

Are plain radiographs of the spine necessary during evaluation after blunt trauma? Accuracy of screening torso computed tomography in thoracic/lumbar spine fracture diagnosis.

BACKGROUND: Fracture of the thoracolumbar (TL) spine is reported in 8 to 15% of victims of blunt trauma. Current screening of these patients is done with conventional radiography. This may require repeated sets of films and take hours to days. It is imperative that these patients get timely, accurate evaluation to allow for treatment planning and early mobilization; alternatives to plain films would aid in this. The objective of this study is to determine whether the data obtained from admission chest/abdomen/pelvis (CAP) computed tomography (CT) scans after blunt trauma has utility in thoracolumbar spine evaluation. METHODS: The records of all patients admitted to a Level I trauma center over a 2-month period who underwent CAP CT were reviewed for the presence of TL spine fracture, time to completion of plain film evaluation, and clinical course. Admission CT scans were reviewed by an attending radiologist who was blinded to any previously diagnosed spine fractures. The two tests were compared for diagnostic accuracy and their discriminatory ability was compared using receiver operating characteristic (ROC) curves. Significance was defined as p < 0.05. RESULTS: In all, 103 patients were admitted from January 1, 2003 to February 28, 2003 and underwent CAP CT scan as part of their initial trauma evaluation. Of these, 26 (25%) had thoracolumbar fractures. Seven (27%) thoracolumbar fractures were not seen on plain radiographs taken during the trauma evaluation. Average time until plain film completion in this group was 8 hours (range, 44 minutes to 38 hours). All 26 (100%) patients with fractures, however, were diagnosed on CT scan performed shortly after admission. Of the remaining 77 patients, two (2.6%) were falsely read as positive for fracture on CT. Sensitivity and specificity of CT scan for thoracolumbar fracture were excellent at 100% and 97%, respectively, with a negative predictive value of 100%. Plain radiographs were 73% sensitive, 100% specific, and had a negative predictive value of 92%. Area under the ROC curve for CT was 0.98, but for plain film was 0.86 (p < 0.02). CONCLUSION: Admission CAP CT obtained as part of the routine trauma evaluation in these high-risk patients is more sensitive than plain radiographs for evaluation of the TL spine after blunt trauma. In addition, CAP CT can be performed faster. Omission of plain radiographs will expedite accurate evaluation allowing earlier treatment and mobilization.

Adult↗
PubMed2005

Selective management of cardiovascular dysfunction in posttraumatic SIRS and sepsis.

Cardiovascular dysfunction associated with the systemic inflammatory response syndrome (SIRS) is caused by a combination of decreased myocardial contractility and low vascular resistance. The contribution of each of these components can be determined at the bedside, and directed therapy can be appropriately initiated. Over an 8-month period of time, 23 consecutive patients who experienced posttraumatic SIRS while still being monitored with a volumetric pulmonary artery catheter (PAC) were prospectively evaluated. Ventricular pressure-volume diagrams were constructed to quantify myocardial contractility and afterload. In a resuscitation protocol, dobutamine was administered to patients with an isolated decrease in contractility, and dopamine or epinephrine was instituted for the combination of reduced contractility and afterload. Variables describing cardiovascular function were measured at the time of resolution of initial shock resuscitation (BASE), at the onset of SIRS (ONSET), and after administration of inotropic or vasoactive agents (TREAT). ONSET was associated with a significant decrease in left ventricular power (LVP) (362 +/- 96 to 235 +/- 55 mmHg.L/min/m(2), P < 0.00001) and stroke work index (SWI) (4670 +/- 1213 to 3060 +/- 848 mmHg.mL/m, P < 0.00001) from BASE. Sixteen patients (70%) demonstrated predominantly decreased contractility, which returned to near BASE values after the administration of dobutamine. The remaining seven patients (30%) had both decreased contractility and afterload, which was treated with dopamine or epinephrine. LVP and SWI significantly increased (235 +/- 55 to 328 +/- 77 mmHg.L/min/m(2), P < 0.00001, and 3060 +/- 848 to 4554 +/- 1423 mmHg.mL/m(2), P < 0.00001, respectively) on the initiation of directed therapy. Specific cardiovascular abnormalities can be identified at the bedside, and this information can guide pharmacologic management. Directed therapy improves cardiovascular function.

Adult↗
PubMed2004

Prospective evaluation of vacuum-assisted fascial closure after open abdomen: planned ventral hernia rate is substantially reduced.

OBJECTIVE: The goal of this report is to examine the success of vacuum-assisted fascial closure (VAFC) under a carefully applied protocol in abdominal closure after open abdomen. SUMMARY BACKGROUND DATA: With the development of damage control techniques and the understanding of abdominal compartment syndrome, the open abdomen has become commonplace in trauma patients. If the abdomen is not closed in the early postoperative period, the combination of adhesions and fascial retraction frequently make primary fascial closure impossible and creation of a planned ventral hernia is required. We have previously reported our experience with the development of a technique for VAFC that allowed for closure of the fascia in many such patients long after initial operation. During this previous study, during which the technique was being developed, VAFC was successful in 69% of patients in whom it was applied, and 22 patients were successfully closed at > or = 9 days after initial surgery (range, 9 to 49 days). A protocol for the use of VAFC in patients with open abdomen was developed on the basis of these data and has been employed since October 2001. The outcome of this protocol's use is examined. METHODS: This is a prospective evaluation of all trauma patients admitted to Wake Forest University Baptist Medical Center over a 19-month period who required management with an open abdomen. VAFC employs suction applied to a large polyurethane sponge under an occlusive dressing in the wound and allows for constant medial traction of the abdominal fascia. It is attempted in all patients in whom the rectus muscles and fascia are intact. Studied variables include fascial closure rate, time to closure, incidence of wound dehiscence, and hernia development after closure. RESULTS: From November 1, 2001, through May 31, 2003, 212 laparotomies were performed in injured patients; 53 (25%) of these patients required open abdomen management. Mean injury severity score for the group was 34, with an average abdominal abbreviated injury score of 2.9. Forty-five (78%) survived until abdominal closure. Vacuum dressings were used in all 45 but VAFC was not attempted in 2 patients (1 due to development of enterocutaneous fistula, 1 because a rectus flap was used for another wound). Closure rate in those undergoing VAFC was 88% (38), with mean time to closure being 9.5 days. This is significantly higher than the 69% rate of fascial closure during the time in which the technique was developed (P = 0.03). Twenty-one patients (48%) were closed at > or =9 days (range, 9 to 21 days). Two patients (4.6%) developed wound dehiscence and underwent successful reclosure. One patient (2.3%) developed a ventral hernia on follow-up, which has since been repaired CONCLUSIONS: The use of VAFC under a carefully defined protocol has resulted in significantly higher fascial closure rates, obviating the need for subsequent hernia repair in most patients. The utility of this technique is not limited to the early postoperative period, but it can be successful as much as 3 to 4 weeks after initial operation.

Abdominal Injuries↗
PubMed2004

Relationship of early hyperglycemia to mortality in trauma patients.

INTRODUCTION: 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. METHODS: 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 (glucose > or =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. RESULTS: From 1/00-12/01, 516 eligible patients were admitted to the ICU after injury. Early hyperglycemia occurred in 483 at the > or =110 mg/dL level, 311 at the > or =150 mg/dL level, and 90 patients at the > or =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, glucose > or =150 mg/dL, and glucose > or =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 glucose > or =110 mg/dL. Multiple logistic regression to control for the effect of age, ISS, GCS score, and BD found early glucose > or =200 mg/dL to be an independent predictor of both infection and mortality while no such relationship was found with > or = 110 mg/dL or > or =150 mg/dL. CONCLUSIONS: Early hyperglycemia as defined by glucose > or =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 of > or =110 mg/dL or > or =150 mg/dL. These data support the need for a prospective analysis of tight glucose control, keeping serum glucose <200 mg/dL in critically ill trauma patients. However, aggressive maintenance of levels <110 mg/dL as reported by others may not be necessary.

Academic Medical Centers↗
PubMed2004

A note on the disjointed nature of the injury severity score.

OBJECTIVE: The Injury Severity Score (ISS) is widely used for anatomic severity assessments. The ISS is the sum of the squares of a patient's three worst Abbreviated Injury Scale (AIS) severities (1-6) from three specified body regions. The set of three AIS severities (including 0s) is called a "triplet." ISS values of 9, 17, 18, 25, 26, 27, 29, 33, 34, 41, and 50 can originate from two unique triplets, but it is not clear whether the mortalities of the triplets are equal. A related question regards the monotonicity of the ISS, that is, whether mortality increases with successive values of ISS. This study sought to compare the mortality of equivalent ISS values from different triplets and to evaluate whether ISS is a monotonic function of mortality. METHODS: The ISS, its corresponding three-digit triplet, and the ICISS (an International Classification of Diseases, Ninth Revision-based competing score) were calculated for 361,381 National Trauma Data Bank patients. Fisher's exact tests were used to test for mortality differences between triplets that yield the same ISS. Plots of mortality by score value were produced to visually assess the monotonicity of the ICISS and the ISS. RESULTS: Six of the 11 triplet pairs had mortalities that differed by greater than 20%, with the largest difference being 32% for an ISS of 25 (triplets 0, 0, 5 and 0, 3, 4). Two other values (9 and 17) have triplet pairs whose mortality differences are less but still statistically different. The ISS is markedly nonmonotonic and is characterized by large spikes in mortality for successive ISS values. Plots of the ICISS show it to be largely monotonic. CONCLUSION: The ISS is a nonmonotonic, triplet-dependent function of mortality. Those who persist in using the ISS to describe populations or make risk adjustments should do so cautiously, being sure to account for triplet type. These suspect ISS values appear in approximately 25% of cases.

Humans↗
PubMed2004

Non-helmeted motorcyclists: a burden to society? A study using the National Trauma Data Bank.

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.

Accidents, Traffic↗
PubMed2003

Videotape review leads to rapid and sustained learning.

BACKGROUND: Performance review using videotapes is a strategy employed to improve future performance. We postulated that videotape review of trauma resuscitations would improve compliance with a treatment algorithm. METHODS: Trauma resuscitations were taped and reviewed during a 6-month period. For 3 months, team members were given verbal feedback regarding performance. During the next 3 months, new teams attended videotape reviews of their performance. Data on targeted behaviors were compared between the two groups. RESULTS: Behavior did not change after 3 months of verbal feedback; however, behavior improved after 1 month of videotape feedback (P <0.05) and total time to disposition was reduced by 50% (P <0.01). This response was sustained for the remainder of the study. CONCLUSIONS: Videotape review can be an important learning tool as it was more effective than verbal feedback in achieving behavioral changes and algorithm compliance. Videotape review can be an important quality assurance adjunct, as improved algorithm compliance should be associated with improved patient care.

Clinical Competence↗
PubMed2003

Complex blunt aortic injury or repair: beneficial effects of cardiopulmonary bypass use.

OBJECTIVE: To compare the outcomes and associated morbidity in patients with blunt aortic injury (BAI) repaired using cardiopulmonary bypass versus no bypass. Special consideration is given to the influence of bypass in the outcome of complex injuries or repair circumstances. SUMMARY BACKGROUND DATA: There are conflicting data concerning the utility of bypass techniques in the operative management of BAI, and controversy over the subject persists. During the last decade, surgeons at the authors' institution have undergone a change in philosophy concerning management of these injuries and began almost exclusively using cardiopulmonary bypass for the repair in 1996. This project explores the effects of this change in the management of BAI. METHODS: The records of all patients with BAI admitted to a level 1 trauma center over a period of 12 years were reviewed for demographics, injury characteristics, operative technique, and outcome. The bypass group was compared to the no bypass group with respect to morbidity and mortality. Those with a complex injury or repair (CI/R) were examined as a subgroup. CI/R was defined as the presence of an injury with extension proximal to the subclavian artery, involvement of branch vessels, or requirement of maneuvers interfering with anastomosis construction, such as cardiac massage. RESULTS: From January 1, 1990, to December 31, 2001, 91 patients were admitted to Wake Forest University Baptist Medical Center with BAI. Sixty-five of these underwent operative repair. Sixty (32 no bypass, 28 bypass) survived to the immediate postoperative period. Injury Severity Score was similar (33 no bypass, 31 bypass, P =.48), as was admission base deficit (-9.2 m Eq/L no bypass vs. -7.0 mEq/L B, P =.13). Paraplegia occurred in four (12%) of the no bypass group as opposed to 0 of the bypass group (P =.05). No patient in the bypass group experienced complications related to heparinization, and two (7%) experienced bypass-related complications (cerebral edema, femoral vein laceration). Mean clamp time for the entire group was 27 minutes. Examination of the 10 patients with CI/R who survived the operating room showed markedly longer clamp times (59 minutes vs. 22 minutes, P <.0001) and a higher rate of paraplegia/paresis (30% vs. 2%, P =.01) as compared to those without CI/R. Logistic regression demonstrated a significant relationship between increasing clamp time and the CI/R classification (P =.007). All three (100%) of the CI/R patients repaired via clamp-and-sew technique developed paraplegia, while none of the seven CI/R patients repaired on bypass developed neurologic changes (P =.008). CONCLUSIONS: With the use of cardiopulmonary bypass in the repair of BAI, the incidence of paraplegia/paresis has fallen. While patients with typical injuries and uncomplicated repair can expect good results with either technique, cardiopulmonary bypass provides significant advantages in the repair of those with CI/R. With the use of bypass, no CI/R patient developed paraplegia, while all CI/R patients experienced paraplegia before bypass use. Although others have reported the importance of clamp time, in this series clamp time appeared largely to be a surrogate variable for complexity of injury.

Adult↗
PubMed2003

External fixation or arteriogram in bleeding pelvic fracture: initial therapy guided by markers of arterial hemorrhage.

BACKGROUND: Bleeding pelvic fractures (BPF) carry mortality as high as 60%, yet controversy remains over optimal initial management. Some base initial intervention on fracture pattern, with immediate external fixation (EX FIX) in amenable fractures aimed at controlling venous bleeding. Others feel ongoing hemodynamic instability indicates arterial bleeding, and prefer early angiography (ANGIO) before EX-FIX. Our aim was to evaluate markers of arterial bleeding in patients with BPF, thus identifying patients requiring early ANGIO regardless of fracture pattern. METHODS: Patients with pelvis fracture were identified from a Level I trauma center registry over a 7-year period and records reviewed. From this group, two subsets were analyzed: those with initial hypotension related to pelvic fracture, and those without hypotension who underwent pelvic ANGIO. Data included hemodynamics, response to resuscitation, presence of contrast blush on CT, fracture treatment and outcome. Adequate response to initial resuscitation (R) was defined as a sustained (>2 hours) improvement of systolic blood pressure to >90 mm Hg systolic after the administration of < or = 2 units packed red blood cells. Those with repeated episodes of hypotension despite resuscitation were classified as non-responders (NR) RESULTS: From 1/94-1/01, 1171 patients were admitted with pelvic ring fracture. Thirty-five (0.3%) had hypotension attributable to pelvis fracture. 28 fell into the NR group, and 26 of these underwent ANGIO. Nineteen (73%) showed arterial bleeding while 3 resuscitation response patients underwent ANGIO with none demonstrating bleeding (p = 0.03). Sensitivity and specificity of inadequate response to initial resuscitation for predicting the presence of arterial bleeding on ANGIO were 100% and 30% respectively while negative and positive predictive value were 100% and 73%. In patients with fractures amenable to external fixation (n = 16), 44% had arterial bleeding on ANGIO, and all were in the NR group. An additional 17 patients without hypotension also underwent ANGIO. Contrast blush on admission CT was seen in 4, 3 of which had arterial bleeding seen on ANGIO (75%). Sensitivity and specificity for contrast blush in predicting bleeding on ANGIO were 60% and 92% with positive and negative predictive value being 75% and 85%. CONCLUSIONS: In patients with hypotension and pelvic fracture, therapy selection based on initial response to resuscitation in BPF yields a 73% positive ANGIO rate in NR patients. Delay in ANGIO for EX FIX in patients with amenable fractures would have delayed embolization in the face of ongoing arterial bleeding in 44% of patients. In stable patients with pelvic fracture, contrast blush also indicates a high likelihood of arterial injury and ANGIO is indicated. Optimal therapy in the face of BPF requires early determination of the presence of arterial bleeding so that ANGIO can be rapidly obtained, and response to initial resuscitation as well as the presence of contrast blush aid in this decision.

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