James E. Barone

Outcome analysis of Pennsylvania trauma centers: factors predictive of nonsurvival in seriously injured patients.

BACKGROUND The purpose of this study was to evaluate the impact of five trauma center characteristics on survival outcome in nine serious injury categories. METHODS A retrospective analysis of prospectively collected data from 1992 to 1996 on patients older than 14 years of age from 24 accredited trauma centers in Pennsylvania was performed. Trauma center characteristics selected for evaluation were level of accreditation, volume of trauma admissions, presence of in-house trauma surgeons, presence of a surgical residency program, and presence of an on-site medical school. Each of these characteristics was evaluated to determine its impact on survival in the selected serious injuries. A logistic regression model was then created to evaluate the most seriously injured patients as defined by A Severity Characterization of Trauma score of < 0.50. On the basis of the logistic regression model, odd ratios were calculated treating low volume as a significant risk factor for mortality. RESULTS Of the 88,723 patients meeting registry criteria, 13,942 met the serious injury criteria. Independent analysis suggested that accreditation was beneficial regardless of level, volume of patients treated had a direct impact on survival outcome, and the presence of a surgical residency program may confer survival benefit. Of the 13,942 patients with serious injuries, those with A Severity Characterization of Trauma score of < 0.5 were selected for evaluation by logistic regression (n = 3,562). The logistic regression model, however, showed that only volume of patients treated had a consistent association with improved survival. Odds ratio analysis revealed low volume as a significant risk factor for mortality in seven of the nine injuries studied. CONCLUSION In this analysis, only volume of patients treated had a direct impact on survival outcome. Accreditation, regardless of level, appears to be beneficial.

Validation of new trauma triage rules for trauma attending response to the emergency department.

INTRODUCTION The American College of Surgeons Committee on Trauma has suggested triage criteria for the immediate attendance of a trauma surgeon to an injured patient in the emergency department. This study validates the accuracy of these criteria in identifying high-risk trauma patients and assesses the impact of trauma surgeon response time. METHODS A study group of trauma patients with a systolic blood pressure (SBP) < 90 mm Hg, Glasgow Coma Scale (GCS) score < 8, airway compromise managed with endotracheal intubation (ETI) or surgical airway, or gunshot wound (GSW) to the neck or torso were compared with a control group of patients meeting none of these criteria. Outcome measurements included Injury Severity Score (ISS), duration of hospitalization (length of stay [LOS]), intensive care unit (ICU) days, direct transfer to the ICU or operating room, and mortality. For the study group, trauma surgeon response times, < or = 15 minutes and > 15 minutes, were compared for age, ISS, LOS, ICU days, mortality, and direct transfer to the ICU or operating room. Statistical analysis was performed using the t test and the Yates-corrected chi(2) test (p < 0.05), with odds ratios calculated on the basis of trauma activation criteria and outcome measures. Multiple logistic regression was used to assess the relation between the independent variables SBP, GCS, ETI, and GSW with direct transfer to the ICU or operating room and mortality. RESULTS A total of 4,910 patients were identified, including 791 study group patients. The mean ISS, LOS, ICU days, and mortality were significantly higher in the study group (p < 0.01). Odds ratios of the study group for direct transfer to the ICU or operating room were 91 and 2 for ETI, 23 and 1.4 for GCS score < 8, 8 and 2.2 for GSW, and 7 and 1.6 for SBP < 90 mm Hg, respectively. The odds ratios for mortality were 39 for ETI, 104 for GCS score < 8, 12 for GSW, and 74 for SBP < 90 mm Hg. Regression analysis demonstrated that GSW, SBP < 90 mm Hg, and ETI predicted ICU admission; GSW, SBP < 90 mm Hg, and ETI predicted operative intervention; and GCS score < 8, SBP < 90 mm Hg, and ETI were associated with mortality. Trauma surgeon response times were available for 658 (83%) of the study group patients. No significant differences were found between the two response groups. CONCLUSION Trauma patients meeting the triage criteria proposed by the American College of Surgeons Committee on Trauma have more severe injuries, a higher mortality rate, and longer hospital and ICU stays than control patients. SBP < 90 mm Hg, ETI, and GSW are predictive of urgent operating room use and ICU admission. A significantly higher mortality rate is associated with SBP < 90 mm Hg, ETI, and GCS score < 8. Incorporating these criteria into trauma center triage rules to identify high-risk injured patients is warranted. However, trauma surgeon response time < or = 15 minutes was not associated with improved patient outcome, and optimal response time remains uncertain.

Management of Blunt splenic trauma in patients older than 55 years

BACKGROUND Many experts have suggested that blunt splenic trauma in patients older than 55 years should not be managed by observation because of supposed increased fragility of the spleen and decreased physiologic reserve in elderly patients. We sought to determine the outcome of nonoperative management of blunt splenic trauma in patients older than 55 years. METHODS For the years 1994 through 1996, data for patients with splenic injury older than 55 years from seven trauma centers in a single state were reviewed. RESULTS Blunt splenic trauma occurred in 41 patients older than 55 years. Eight patients were excluded from further analysis because of death from massive associated injuries within 24 hours of admission. The remaining 33 patients (mean age, 72+/-10 years) were divided into two groups: immediate exploration (10 patients) and observation (23 patients). Observation of blunt splenic injury failed in 4 of 23 patients (17%). No patient deaths were related to the method of management of the splenic injury. CONCLUSIONS Observation of the elderly patient with blunt splenic trauma has an acceptable failure rate of 17%.

Using queueing theory to determine operating room staffing needs.

BACKGROUND To meet American College of Surgeons criteria, Level I and II trauma centers are required to have in-house operating room (OR) staff 24 hours per day. According to the number of emergency cases occurring, hospitals may have varying needs for OR staffing during the night shift. Queueing theory, the analysis of historic data to provide optimal service while minimizing waiting, is an objective method of determining staffing needs during any time period. This study was done to determine the need to activate a backup OR team during the night shift at a designated, verified Level II trauma center. METHODS The basic queueing theory formula for a single-phase, single-channel system was applied to patients needing the services of the OR. The mean arrival rate was determined by dividing the number of actual cases by 2,920 hours in a year (8 hours per night x 365). The mean service rate is determined by averaging the length of the actual cases during the period studied. Using the mean arrival rate and the mean service rate, the probability of two or more patients needing the OR at the same time was determined. This probability was used to reflect the likelihood of needing to activate the backup OR team. Simulation was then used to calculate the same probability and validate the results obtained from the queueing model. RESULTS All OR cases (n = 62) beginning after 11 PM and before 7 AM from July 1, 1996, through June 30, 1997, were analyzed. During the study period, the average arrival rate (A) was one patient every 5.9 days (0.0212 patient every hour), with an average service rate (mu) of 80.79 minutes per patient (0.7427 patients per hour). According to queueing theory, lambda = 0.0212 patients per hour, mu = 0.7427 patients per hour, lambda/mu = 0.0285, the probability of no patients being in the system (P0) = 0.9714, P1 = 0.0278, P> or =2 = 1 - (0.0278 + 0.9714) = 0.0008. The probability of two or more cases occurring simultaneously on the night shift is less than 0.1%. CONCLUSION In our institution, activation of a second OR team is unnecessary when the first team is busy with a case on the night shift because the likelihood of two cases occurring concurrently is less than one in a thousand. Queueing theory can be a valuable tool to use in determining the staffing needs of many hospital departments. Trauma centers should apply this mathematical model in optimizing the use of their operational resource.

Expanding Handgun Bullets

BACKGROUND Many new types of expanding or fragmenting handgun ammunition have been developed. Knowledge of these unusual bullets may aid in the management of patients and their wounds. METHODS Eleven different expanding or fragmenting .45 caliber bullets and a nondeforming, full metal jacketed bullet for comparison were fired multiple times from the same handgun into both a water reservoir and ordnance gelatin. Performance was observed and recorded. Muzzle velocities were measured using a chronograph. Bullets were disassembled and cross-sectioned to facilitate inspection. RESULTS The distinguishing surface and internal features of each bullet are described. When fired into water and ordnance gelatin, the bullets reliably expanded to 1.49 to 1.89 times their prefired diameters. Rates of kinetic energy loss of bullets of equal mass fired into ordnance gelatin were plotted. Full metal jacketed bullets penetrated twice as deeply as deforming bullets. Jackets of some of the expanding bullets separated when fired into water. CONCLUSION Expanding/fragmenting bullets produce larger, shallower wounds than do full metal jacketed bullets. Recognition of the wound and roentgenographic appearances of these unusual bullets will help the trauma surgeon to properly treat gunshot victims. Because of the occurrence of jacket separation in water, ordnance gelatin should be used for optimal evaluation of bullet performance.

Fever: Fact and fiction.

The significance and management of fever in surgical patients involves several misconceptions that have been perpetuated over the years. This review addresses nine such misconceptions and using evidence from the literature, attempts to clarify such diverse issues as the concept of normal body temperature, the investigation and rationale for the treatment of postoperative fever, the beneficial effects of fever and the potential adverse effects of suppressing fever.

Munchausen syndrome presenting as trauma.

Rarely, a patient with Munchausen syndrome will present with apparent trauma. A computerized literature search from 1966 until the present discovered only three such case reports, none of which appeared in a surgical journal. We report a fourth case. The characteristics of Munchausen syndrome are illustrated. The possibility that such a patient may have a true injury is also discussed.