Preinjury warfarin does not impact outcome in trauma patients.

OBJECTIVE: The objective of this study was to determine whether the preinjury condition of anticoagulation had an adverse impact on patients sustaining injury. METHODS: A retrospective analysis was performed for prospectively collected registry data from 1995-2000 from all accredited trauma centers in Pennsylvania. The registry was queried for all trauma patients who had anticoagulation therapy as a preinjury condition (PIC). This group served as our experimental cohort. A control cohort (not having warfarin therapy as a PIC) was developed using case-matching techniques for age, sex, Glasgow Coma Scale (GCS), Injury Severity Score (ISS), A Severity Characterization of Trauma (ASCOT) score, and in the head injured patients, International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnoses. Head and non-head injured patients were evaluated separately. The cohorts were examined for 28-day mortality, intensive care unit length of stay (ICU-LOS), hospital length of stay (HOS-LOS), PICs, occurrences, discharge destinations, and functional status at discharge. Chi2 and Student's t test were used to evaluate the data; p values < 0.05 were considered significant. RESULTS: Two thousand nine hundred forty-two patients were available for analysis. The prevalence of PICs was significantly greater in the warfarin group for both the head and non-head injured populations (p < 0.003 and p < 0.0001, respectively). The incidence of occurrences in the non-head injured population was statistically higher for the warfarin patients (p < 0.001), but showed no difference in the head injured group regardless of warfarin use (p = 0.15). Functional status at discharge demonstrated no clinically significant difference between the warfarin and non-warfarin groups in both head and non-head injured populations. There was no difference in discharge destination in the head injured population; however, in the non-head injured population a greater percentage of non-warfarin patients was discharged to home when compared with the warfarin patients. CONCLUSION: Our data suggest that the PIC of anticoagulation with warfarin does not adversely impact mortality or LOS outcomes in both head and non-head injured patients. In non-head injured patients, however, the occurrence rates and discharge destination were different. More research needs to be done to determine whether this is related to anticoagulation or other reasons (i.e., number of PICs). These data should be used when weighing risk/benefit ratios of prescribing chronic anticoagulation.

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.

Influence of restraining devices on patterns of pediatric facial trauma in motor vehicle collisions.

In the Commonwealth of Pennsylvania, it is required that all children under the age of 4 years be restrained by an infant seat or car seat appropriate for their age and weight. Furthermore, all individuals riding in the front seat must be restrained by a seatbelt. This study examined the relationship between patterns of facial injuries and the use of restraining devices in the pediatric population. A retrospective analysis was performed on motor vehicle collision data submitted to the Pennsylvania Trauma Outcome Study database from 1990 through 1995. Criteria for submission included trauma patients who were admitted to the Intensive Care Unit, those who died during hospitalization, those who were hospitalized for more than 72 hours, or those who were transferred in or out of the receiving hospital. A subset of 412 pediatric patients, 15 years of age or younger, was analyzed for patterns of facial injury and the presence or absence of restraining devices. Restraining devices were categorized as a car seat or a seatbelt. Statistical analysis was performed using chi-square and Fisher's exact tests. Of the 412 pediatric patients, only 17 children were restrained with a car seat and 121 were wearing a seatbelt. A total of 30 children sustained facial fractures, and 50 children suffered facial lacerations. There was a statistically significant increase in the incidence of facial fractures with increasing age of the child (p < 0.001). Of children with facial fractures, 70 percent of those 5 to 12 years old and 90 percent of those 13 to 15 years old were unrestrained (p = 0.166). In conclusion, despite legislation mandating the use of restraints, a large proportion of children involved in motor vehicle collisions were unrestrained. Furthermore, there seems to be a direct relationship between the age of a child and the incidence of facial fractures sustained in motor vehicle collisions.

Comparison of a new method for computer analysis with standard techniques for measuring survival rates in the rat transverse rectus abdominis musculocutaneous flap.

Many methods have been used to measure experimental flap survival in animal models. These have previously included planimetry, computer programs, and (routinely by the authors) the simple measurement of the weight of a template traced according to the dimensions of a given flap. To test the validity of their method, an alternative technique was developed by the authors' biostatiticians. Initially, in a study of rat transverse rectus abdominis musculocutaneous (TRAM) flaps, all templates were also scanned electronically to form bitmaps. Using commonly available software programs, each bitmap was colorized corresponding to viable and nonviable areas of the flaps. A summation of individual pixels by color could then be used to calculate the percentage of flap survival. A comparison of both methodologies in 64 rat TRAM flaps found that the survival rate was slightly greater overall when a computer analysis had been performed (3.1 +/- 1.7%), but this was not a significant difference (p = 0.479). Thus, the previous standard method was proven reliable, but just as precise calculations are now possible using the convenience of any personal computer.

Measurement of endotracheal tube cuff leak to predict postextubation stridor and need for reintubation.

BACKGROUND: The purpose of this study was to determine the predictive value of an endotracheal tube cuff leak for the development of postextubation stridor and the need for reintubation. STUDY DESIGN: Consecutive trauma patients who required intubation at a level I trauma center from July 1997 to July 1998 were studied prospectively. Pediatric patients and those who did not meet the standard weaning protocol criteria established by the Division of Trauma and Surgical Critical Care were excluded. Injury Severity Score, endotracheal tube size, reason for intubation, and the number of days intubated before the initial extubation attempt were recorded. At the time of extubation, the difference in exhaled tidal volume from before to after endotracheal tube cuff deflation was calculated. This number was then divided by the exhaled tidal volume before cuff deflation and was recorded as the percent cuff leak. Patients were followed for 24 hours after extubation for the development of stridor or need for reintubation. Statistical analysis to compare subgroups of patients was performed using ANOVA with Scheffé post hoc analysis. RESULTS: Among the 110 patients analyzed, the most common reason for intubation was closed-head injury. Seven patients (6.4%) developed stridor alone and had a mean cuff leak of 5 8 mL (8.4% of tidal volume before cuff deflation). Six patients (5.5%) experienced stridor that required reintubation and had a mean cuff leak of 68 mL (9.2% of tidal volume before cuff deflation). Patients who developed stridor or needed reintubation had been intubated for a significantly greater length of time than those not developing stridor or requiring reintubation (2.6 versus 3.0 days, p < 0.001). There were no differences in Injury Severity Score, endotracheal tube size, or reason for intubation between these groups. CONCLUSIONS: A cuff leak of less than 10% of tidal volume before cuff deflation is useful in identifying patients at risk for stridor or reintubation (96% specificity). It appears that the amount of cuff leak decreases after intubation for more than 3 days, increasing the risk of stridor and need for reintubation. This information may be helpful in identifying those patients who need treatment for laryngotracheal edema, ie, use of steroids or anesthesia during extubation, the efficacy of which remains to be determined.

The influence of air bags and restraining devices on extremity injuries in motor vehicle collisions.

The influence of air bags and other restraining devices on injury after motor vehicle collisions is not well defined. This study examined the relationship between the use of restraining devices and the incidence of extremity injuries in motor vehicle collisions. A retrospective analysis was performed on motor vehicle collision data submitted to the Pennsylvania Trauma Outcome Study database from 1990 through 1995. Criteria for submission included trauma patients who were admitted to the intensive care unit, who died during hospitalization, who were hospitalized for more than 72 hours, or who were transferred in or out of the receiving hospital. A total of 21,875 patients met these criteria. These patients were analyzed for the presence or absence of upper and lower extremity injuries and were compared based on their use of restraining devices. Restraining devices were categorized into four groups: air bag alone, air bag and seat belt, seat belt or carseat without air bag, and no restraining device. Statistical analysis was performed using the chi-squared test of association. For contingency tables with small expected frequencies, Fisher's exact test was used. Study participants included 11,688 men and 10,185 women with a mean age of 38 +/- 20 years. There were 16,033 drivers and 5,842 passengers. Air bags were deployed in 472 instances. In 297 of these cases, additional restraint was provided with a seat belt. In 6,632 cases, air bags were not deployed; however, patients were restrained with either a seat belt or a carseat. In 14,771 cases, patients were not restrained. When comparing restraining devices as a group vs. no restraint, there was a significant decrease in the incidence of upper (p = 0.018) and lower (p < 0.001) extremity injuries. Air bags, however, were associated with an increased incidence of both upper (p = 0.033) and lower (p = 0.002) extremity injuries when compared with no restraint or when compared among patients who were restrained. As a group, restraining devices decrease the incidence of upper and lower extremity trauma sustained by patients injured in motor vehicle collisions. Air bags, however, are associated with an increased incidence of upper and lower extremity injuries when compared with seat belts alone or when no restraining devices are used.

Evidence for the Will Rogers phenomenon in migration of employees to managed care plans.

Employees have increasing opportunities to enroll in managed care plans, and employers tend to favor these plans because of their lower costs. However, lower costs may be the result of selection of healthier patients into managed care plans. This study measured differences in health care utilization across an indemnity plan and a managed care plan, and for all employees together. We found that apparent increases in utilization in both indemnity and managed care plans disappeared when the plans were viewed together, reflecting the migration of sicker patients from indemnity plans to managed care plans.

A software program to calculate Goodman and Kruskal's gamma: a method to monitor surgical-site infection rates.

Several studies have described a need for a valid statistical methodology to facilitate interhospital and intrahospital infection rates for their operative procedures. Physician awareness of postoperative surgical-site infection rates has been demonstrated as an effective means to reduce infection rates in both high- and low-risk surgical patients. This article presents a new software program that allows for simple data entry and provides results including the gamma statistic, sample size, variance, standard error, and Z value and P value of the gamma result. This software also provides a data interpretation table, allowing infectious disease department physicians or staff to determine if a significant relation exists between operative procedure infection rates and patient risk factors.

Outcome of blunt thoracic aortic injury in a level I trauma center: an 8-year review.

BACKGROUND: The purpose of this study was to evaluate our experience with blunt thoracic aortic injury and identify factors predictive of outcome. METHODS: Hospital charts, trauma registry data, and autopsies of 64 patients with blunt thoracic aortic injury from 1988 to 1995 were reviewed. RESULTS: Patients were identified and segregated based on admission physiology. Group 1 patients (n = 19) arrived in arrest. Group 2 patients (n = 10) arrived in shock with systolic BP 90. Group 3 patients (n = 35) arrived with systolic BP>90. All patients in groups 1 and 2 expired. Injury Severity Scores for nonsurvivors in group 3 (n = 12) were significantly higher than survivors. There were no significant differences when comparing time of injury to repair or arrival between groups, or in mortality or paralysis comparing repair techniques or clamp/bypass times. Double lumen endotracheal tubes caused significant operative delays compared to single lumen tubes. CONCLUSIONS: Predictors of survivability were hemodynamic stability on arrival and lower Injury Severity Scores. In thoracic aortic injury patients arriving hemodynamically stable, Injury Severity Score correlated with mortality but not paralysis.

Role of magnetic resonance imaging in the diagnosis of osteomyelitis in diabetic foot infections.

PURPOSE: The role of magnetic resonance imaging (MRI) in the diagnosis of osteomyelitis in foot infections in diabetics was investigated. The accuracy, sensitivity, and specificity of MRI, plain radiography, and nuclear scanning were determined for diagnosing osteomyelitis, and a cost comparison was made. METHODS: Twenty-seven patients with diabetic foot infections were studied prospectively. All patients underwent MRI and plain radiography. Twenty-two patients had technetium bone scans, and 19 patients had Indium scans. Nineteen patients had all four tests performed. Patients with obvious gangrene or a fetid foot were excluded. RESULTS: The diagnosis of osteomyelitis was established by pathologic specimen (n = 18), bone culture (n = 3), or successful response to medical management (n = 6). Osteomyelitis was confirmed in nine of the pathologic specimens. The diagnostic sensitivity, specificity, and accuracy for MRI was 88%, 100%, and 95%, respectively, for plain radiography it was 22%, 94%, and 70%, respectively, for technetium bone scanning it was 50%, 50%, and 50%, respectively, and for Indium leukocyte scanning it was 33%, 69%, and 58%, respectively. The data were analyzed statistically with the two-tailed Fisher's exact test. MRI was the only test that was statistically significant (p < 0.01). CONCLUSIONS: MRI appeared to be the single best test for the diagnosis of osteomyelitis associated with diabetic foot infections. It had a better diagnostic accuracy than conventional modalities and appeared to be more cost-effective than the frequently used Indium scan.

Childhood injuries and the importance of documentation in the emergency department.

The purpose of this study is 1) to evaluate the extent to which documentation of the medical record is completed for dependent children who present for evaluation of an acute injury, and 2) to examine the factors that favorably or adversely influence completion of the medical record. The emergency department (ED) ledgers of 669 children less than nine years of age were reviewed, including 172 (25.7%) who presented for evaluation of an acute injury. Each of the latter charts was examined for basic demographic data, as well as information about injury type and mechanism, ED provider, and involvement of social services personnel. The ledgers were further examined to determine completeness of chart documentation in several relevant areas, including the circumstances and characteristics of the acute injury, pertinent past medical history, and course of management and referral while in the ED. Each of 15 individual documentation variables was assigned a score of either zero (incompletely/not addressed or documented) or one (completely addressed or documented). The 15 individual scores were equally weighted and summed, resulting in a total documentation score ranging from zero (failure to address or document any of the 15 variables) to 15 (all variables completely addressed/documented). The mechanisms of injury included falls from height (48.3%), direct blunt impact other than falls (26.7%), penetrating injury (6.4%), burn (5.2%), and ingestion (8.1%). Seventeen patients (9.9%) were admitted for primarily medical, and one (0.6%) for primarily social, indications; one patient died as a result of his injuries.(ABSTRACT TRUNCATED AT 250 WORDS)

Transient myocardial ischemia in infants prenatally exposed to cocaine.

This prospective study examined whether neonates of pregnant women who used cocaine during pregnancy are at a risk for the development of transient myocardial ischemia and altered autonomic function, as in adults. We studied 21 of 35 infants with a history of prenatal exposure to cocaine. The ST segment changes and heart rate variability were evaluated from three-channel Holter monitors within 48 hours of birth. The data were compared with those on 20 control infants with similar birth weight, gestational age, and postnatal age. Six infants (29%) who were exposed to cocaine in utero had transient ST segment elevation, versus only one infant (5%) from the control group (odds ratio = 7.6; 95% confidence interval, 1.14, 50.64). Heart rates, results of total power and low-frequency power spectral analyses for heart rate variability, and arrhythmias were not significantly different in the two groups. However, a lower ratio of low-to high-frequency power reflected increased vagal activity in cocaine-exposed infants. We conclude that cocaine use in pregnant mothers is associated with transient ST segment abnormalities in their infants. These abnormalities are consistent with transient myocardial ischemia.

Respiratory syncytial virus-specific immunoglobulins in preterm infants.

Incomplete transfer of maternal antibodies specific to respiratory syncytial virus (RSV) has been suggested as an explanation for the increased risk of RSV infections in preterm infants. Antibodies directed against the two major RSV envelope glycoproteins, F and G, are protective in vitro and in vivo. Our study was conducted to measure IgG, IgG1, IgG2, and IgG3 antibody titers against the RSV F and G glycoproteins in cord sera from infants born at different gestational ages. Titers of neutralizing antibody were measured in a subset of the subjects. The mean (+/- SEM) log2 titers of IgG antibodies directed against the RSV F and G glycoproteins were significantly lower in infants born at < or = 28 weeks of gestation (11.2 and 10.8 for F and G glycoproteins, respectively) than in term infants (12.6 and 12.8 for F and G, respectively) (p < 0.05). Preterm infants born at > or = 29 weeks had titers of antibodies against the F glycoprotein comparable to those of term infants. The highest titers of RSV-specific antibodies were in the IgG1 and IgG2 subclasses. Mean (+/- SEM) neutralizing antibody titers were lower in infants born at < or = 28 weeks (7.7 +/- 0.4) than in term infants (10.2 +/- 0.3) (p < 0.001). We conclude that (1) RSV-specific antibody titers were lower than in term infants only in the most premature infants (< or = 28 weeks) and (2) preterm infants born at > or = 29 or > or = 33 weeks of gestation had RSV-specific titers against F and G glycoproteins, respectively, that were comparable to those of term infants. Preterm infants born at < or = 28 weeks could represent a target population for passive immunoprophylaxis.