Infection in hospitalized trauma patients: incidence, risk factors, and complications.

BACKGROUND: Several factors place victims of multiple trauma at increased risk for infection. The purpose of this study was to delineate the frequency of, types of, and risk factors for infection in hospitalized trauma patients. METHODS: Prospective surveillance for nosocomial infection was conducted for all trauma patients who were admitted for more than 24 hours to a tertiary-care regional trauma center between January 1 and December 31, 1996. RESULTS: A total of 563 patients (414 males) with a mean age of 40 years (range, 15-97 years) were followed. Most (86%) sustained blunt traumatic injuries. A total of 367 infections occurred in 209 (37%) patients for an incidence of 32.1/1,000 patient-days. The hospital stay of 37% of patients was complicated by at least one infection, involving the following sites: lower respiratory tract (28%), urinary tract (24%), surgical wound (18%), skin/soft tissue (13%), intra-abdominal (5%), primary bloodstream (5%), and other sites (8%). Infection was complicated by septic shock in 36 (10%) cases, acute respiratory distress syndrome in 32 (9%) cases, and multiorgan failure in 13 (4%) cases. Death was attributed to infection in four patients. In a multivariate analysis, infected patients were more likely to have been ventilated (odds ratio [OR] = 2.6; p<0.001), to have had multiple surgical procedures (OR = 2.8; p = 0.02), to have received multiple blood transfusions (OR = 2.3; p = 0.04), and to have had a spinal cord injury (OR = 5.0; p = 0.002). First surgical procedure within 24 hours of admission was protective (OR = 0.4, p = 0.001). CONCLUSION: Trauma patients are at high risk for developing infection. Identifying patients who are at increased risk for infection may allow for early intervention and subsequent decrease in infectious morbidity.

Prospective evidence of the superiority of a sonography-based algorithm in the assessment of blunt abdominal injury.

BACKGROUND: Although the routine use of FAST (focused assessment with sonography for trauma) in the evaluation of trauma victims is increasing, to our knowledge, a prospective comparison of contemporary adult trauma victims managed with and without FAST has not been reported in North America. METHODS: Adult victims of blunt trauma for whom there was a suspicion of abdominal injury were managed with one of two diagnostic algorithms, FAST or no-FAST. The two algorithms were compared for diagnostic accuracy, cost, time, and delayed diagnoses. RESULTS: Among 706 patients (mean Injury Severity Score, 23), 460 were managed with FAST and 246 with no-FAST. The two groups were similar with respect to age, Injury Severity Score, prehospital time, and mortality (p = not significant). There were 3 of 460 (0.7%) delayed diagnoses in the FAST group and 4 of 246 (1.6%) in the no-FAST group (p = not significant). The diagnostic accuracy for the FAST and no-FAST algorithms was 99% and 98%, respectfully. The FAST and no-FAST algorithms led to similar rates of laparotomy, 13% and 14%, respectfully, but nonoperative management was more common in the no-FAST group (p < 0.01). The mean diagnostic cost for the FAST algorithm was $156, compared with $540 with the no-FAST algorithm (p < 0.0001) and the mean time required for diagnostic work-up was 53 minutes with the FAST algorithm, compared with 151 minutes with the no-FAST algorithm (p < 0.0001). CONCLUSION: This study has provided prospective evidence that a FAST-based algorithm for blunt abdominal injury was more rapid, less expensive, and as accurate as an algorithm that used computed tomography or diagnostic peritoneal lavage only. Trauma centers are encouraged to incorporate a FAST-based algorithm into their initial management of blunt trauma victims.

Early experience with simulated trauma resuscitation.

Although trauma resuscitation is best taught through direct exposure with hands-on experience, the opportunities for this type of teaching in Canada are limited by the relatively low incidence of serious injury and the consolidation of trauma care to a small number of centres. Simulators have been used extensively outside the health care environment and more recently have been used by anesthetists to simulate intraoperative crises. In this paper early experience using a realistic mannequin, controlled by a remote computer, that simulates a variety of physiologic and injury specific variables is presented. The resource implications of simulated resuscitation are reviewed, including one-time and operating costs. Simulated trauma resuscitation may be an educational alternative to "real-life" trauma resuscitation, but careful evaluation of the benefits and resource implications of this type of teaching through well-designed research studies will be important.

The indeterminate abdominal sonogram in multisystem blunt trauma.

BACKGROUND: North American trauma centers are beginning to note the limitations of emergent torso sonography. The purpose of this prospective study was to evaluate the frequency, causes, associations, and sequelae of indeterminate (IND) sonograms in blunt trauma. METHODS: Among adult blunt trauma patients assessed with screening torso sonography, clinician sonographers recorded the abdominal sonogram as positive, negative, or IND for free fluid. Patients with IND sonograms were further investigated with repeat sonography, computed tomography, or diagnostic peritoneal lavage. RESULTS: Among 417 patients with blunt trauma (mean Injury Severity Score = 21) managed with sonography, there were 28 (6.7%) IND and 389 (93.3%) non-IND sonograms. Sonograms were IND because of patient factors in 71% (20 of 28) and because of operator factors in 29% (8 of 28). None of the 28 patients were managed with repeat sonography alone. All 4 diagnostic peritoneal lavage examinations gave negative results, whereas 8 of 23 computed tomographic scans were abnormal (6 of 8 patients underwent laparotomy). The mean time required for diagnostic workup was 117 minutes in the IND group and 48 minutes in the non-IND group (p < 0.001 in both cases). CONCLUSION: This prospective study has demonstrated that IND sonograms are not common at our center (6.7%), are usually attributable to patient factors, and are associated with greater diagnostic time. Patients with IND sonograms require further investigation because they often have injuries requiring laparotomy.

Head injury in young adults: long-term outcome.

OBJECTIVE: To describe the long-term outcome 5 years after injury of young adults who were 15 to 19 years old at the time of their head injuries. DESIGN: A retrospective cohort. The health records of 62 consecutive eligible subjects were abstracted for baseline sociodemographic, health, and injury variables. A telephone interview was administered to assess quality of life, impairment, disability, and handicap. SETTING: Canada's largest trauma center, Sunnybrook Health Science Centre, Toronto, Canada. SUBJECTS: Of the 58 subjects (94%) who were traced at follow-up, 51 agreed to participate. MAIN OUTCOME MEASURES: The Medical Outcomes Study SF-36, Head Injury Symptom Checklist, selected disability measures, Community Integration Questionnaire. RESULTS: Of the 8 summary items of the Medical Outcomes Study SF-36, subjects scored lowest on mental health. There were no significant differences between mild and more severely injured groups in all quality of life measures. Subjects classified with mild head injury overall reported more symptoms from the Head Injury Symptom Checklist. Subjects with more severe injuries had lower community integration scores (p < .05). CONCLUSIONS: Overall, mental health is an important area of concern at follow-up for all subjects. Adolescents with apparent mild head injury can have disabling symptoms many years after injury.

Measuring injury severity: time for a change?

BACKGROUND: The Injury Severity Score (ISS) does not take into account multiple injuries in the same body region, whereas a New ISS (NISS) may provide a more accurate measure of trauma severity by considering the patient's three greatest injuries regardless of body region. The purpose of this study was to evaluate the ISS and NISS in patients with blunt trauma. METHODS: Consecutive individuals treated from January of 1992 to September of 1996 at one institution were included if they had sustained blunt trauma and satisfied triage standards (n = 2,328). For each patient, we computed the ISS and the NISS to determine how often the two scores were identical or discrepant. Discrepant cases were then further analyzed using receiver operating characteristic curves to determine which score better predicted short-term mortality. RESULTS: The mean ISS was 25 +/- 13, and the mean NISS was 33 +/- 18. The two predictive scores were identical in 32% of patients and discrepant in 68% of patients. Patients with identical scores had a lower mortality rate than patients with discrepant scores (10% vs. 13%; p < 0.02). In patients with discrepant scores, the area under the receiver operating characteristic curves was greater for the NISS than the ISS (0.852 vs. 0.799; p < 0.001), and greater amounts of discrepancy were associated with increasing rates of mortality (p < 0.001). CONCLUSIONS: The NISS often increases the apparent severity of injury and provides a more accurate prediction of short-term mortality. The benefit associated with using the NISS rather than the ISS must be weighed against the disadvantages of changing a scoring system and the potential for still greater improvements.

Changes in red cell transfusion practice among adult trauma victims.

BACKGROUND: Recent attention concerning the adverse outcomes of blood transfusion has resulted in decreased blood product usage for nonemergency care. We hypothesized that there has also been a decrease in blood product use in the management of seriously injured adults. METHODS: A retrospective review of institutional database records was conducted at a regional trauma center for adults admitted during 1991, 1993, and 1995. Data was analyzed for trends in amount, type, and timing of blood product use. RESULTS: A total of 1,738 patients were assessed, with 1,605 meeting inclusion. The three patient groups were similar, including injury severity (overall mean Injury Severity Score of 23.6), mechanism (88% blunt), and survival (87%). In 1991, 54% of the patients were transfused a total of 2,341 units of packed red blood cells (mean 4.67 units/pt treated) versus 42% of patients in 1995 (p < 0.0001) who received 2,018 packed red blood cells (mean 3.57 units/patient treated, p = 0.05). A significantly higher proportion of units was transfused in the first 24 hours of care in 1995 (64%) compared with 1991 (21%, p < 0.0001). A reduction in the use of universal donor type-O blood use was also found (1.21 vs. 0.65 units/patient transfused, p < 0.0001). Despite similar admission hemoglobin concentrations (124.1 vs. 125.3, not significant), significant reductions were found in the average 24-hour (109.2 vs. 103.8, p < 0.001), lowest (96.5 vs 92.1, p < 0.01) and discharge (115.8 vs. 110.5, p < 0.001) concentrations. CONCLUSIONS: Between 1991 and 1995 there have been significant reductions in both the number of trauma patients receiving blood products and the total number of units transfused. These findings may reflect lower or abandoned hemoglobin transfusion triggers and increased awareness of complications related to transfusion.

Cardiac tamponade following minimally invasive direct coronary artery bypass.

We report a case of cardiac tamponade resulting in a death following minimally invasive direct coronary artery bypass. Despite absence of clinical symptoms at the time of hospital discharge, cardiac tamponade physiology may have been evident on close evaluation of Doppler studies of the left internal mammary artery. Performance of a predischarge transthoracic echocardiogram may have been confirmatory and lifesaving.

Repair of congenital pulmonary incompetence by bicuspidization of the pulmonary valve.

We report the successful repair of pulmonary incompetence in an adult due to the congenital absence of the posterior leaflet of the pulmonary valve. The repair consisted of bicuspidization of the pulmonary valve, which achieved competence and eliminated the symptoms and echocardiographic manifestations of right ventricular overload while preserving the native valve.

Lateral impact motor vehicle collisions: significant cause of blunt traumatic rupture of the thoracic aorta.

BACKGROUND: This study was undertaken to determine the relationship between traumatic rupture of the thoracic aorta (TRA) and the direction of impact at the time of motor vehicle crash. METHODS: Retrospective review of TRA patients from two different databases over a 4.5-year period (January 1, 1991 to June 30, 1995): (1) Ontario Coroner's Office records of motor vehicle deaths from Metropolitan Toronto, and (2) the trauma registries of Sunnybrook Health Science Centre and St. Michael's Hospital in Metropolitan Toronto. RESULTS: Ninety-seven patients (81 from the coroner's database and 16 from the adult trauma unit registries) sustained traumatic rupture of the thoracic aorta. Forty-eight cases (49.5%) were a result of lateral impact crashes. Twenty-eight drivers (22 ipsilateral and six contralateral) and 20 passengers (16 ipsilateral and four contralateral) sustained TRA from lateral impact crashes. Ninety-one TRAs (94%) occurred at the peri-isthmic region. CONCLUSION: Lateral impact crashes are a significant cause of TRA. Traumatic rupture of the aorta should be considered with a high index of suspicion after serious lateral impact crashes, just as physicians now consider patients at high risk of TRA after serious frontal impact crashes.

Long-term outcomes in blunt trauma: who goes back to work?

BACKGROUND: Trauma patients continue to improve after discharge from the trauma center, but the completeness of this recovery remains uncertain. The purpose of this study was to compare the characteristics of patients who do and who do not return to work after blunt trauma. METHODS: Consecutive survivors of blunt trauma discharged from a regional trauma center over a 1-year interval (July of 1994 to June of 1995) were included in the study. Patients completed the SF-36 Health Survey and some additional questions related to employment status both at discharge and again after 1 year. Our principal analysis compared patients who were employed and unemployed at 1-year follow-up. RESULTS: Complete data were available for 195 patients. The typical patient was a young man who had been in a motor vehicle collision and had an injury severity score of 25. At 1-year follow-up, 101 patients had returned to work and 94 remained unemployed. Employed individuals were younger (31 vs. 44 years, p < 0.0001), less severely injured (mean injury severity score 23 vs. 27, p < 0.001), and more likely to hold professional jobs (50 vs. 16%, p < 0.0001). Patterns of injury and operative procedures were similar for employed and unemployed patients. However, the average employed patient had fewer days in the intensive care unit (2 vs. 5 days, p < 0.001), a shorter total hospitalization (19 vs. 28 days, p < 0.01), and was more likely to be discharged to home (62 vs. 39%, p < 0.01). At discharge, those who went on to employment had marginally better SF-36 Health Survey scores on seven of the eight scales (all except general health). During the year after discharge, both groups improved significantly, although employed individuals to a greater extent on all scales of the SF-36 Health Survey. CONCLUSIONS: Almost one half of the multiple system blunt trauma patients remain unemployed 1 year after hospital discharge. Those patients who return to work are usually young professionals with a lower severity of injury. Functional status at discharge predicts future employment status, but underestimates the extent of long-term recovery.

Predictors of fetal mortality in pregnant trauma patients.

BACKGROUND: Fetal mortality after trauma is significant. This study was aimed at identifying factors responsible for this high fetal mortality. METHODS: All pregnant trauma patients admitted to the two major Toronto trauma institutions during the period of November of 1991 to February of 1996 with an Injury Severity Score (ISS) > or = 12 were assessed. Data on age, gestation, hypotension, ISS, hemoglobin, blood transfusion, length of stay, disseminated intravascular coagulation (DIC), and specific maternal injury were analyzed retrospectively to determine predictors of fetal mortality by comparison of patients with and without fetal survival. RESULTS: Twenty of a total of 68 pregnant trauma patients qualified for entry into the trauma registry by having an ISS > or = 12. Overall fetal mortality was 65% (13 of 20) for ISS > or = 12, and there was one maternal death (age, 29 years; ISS, 66). There were no statistically significant differences between the fetal death and fetal survival groups in age (29.2 +/- 6.2 vs. 30.4 +/- 3.9 years), gestation (25.3 +/- 10.5 vs. 24.1 +/- 9.2 weeks), lowest systolic blood pressure (98.3 +/- 33.8 vs. 112 +/- 18.0 mm Hg), head injury rate (3 of 13 vs. 1 of 7), extremity injury rate (8 of 13 vs. 2 of 7), abdominal injury rate (4 of 13 vs. 0 of 7), pelvic fracture rate (6 of 13 vs. 1 of 7), and chest injury rate (5 of 13 vs. 3 of 7). However, ISS (27.7 +/- 3.5 vs. 14.2 +/- 11.4), lowest hemoglobin level (78.8 +/- 17.0 vs. 101.9 +/- 17.1), blood transfusions (10.8 +/- 6.3 vs. 0.9 +/- 1.6 units), length of stay (20.9 +/- 16.7 vs. 8.2 +/- 4.9 days), and the incidence of DIC (8 of 13 vs. 0 of 7) were statistically significantly different between the two groups (p < 0.05). All eight patients with abruptio placentae had associated fetal mortality. CONCLUSIONS: Apart from ISS, blood loss, and abruptio placentae; the presence of DIC was the most significant predictor of fetal mortality. This finding may represent stimulation of DIC by placental products entering the maternal circulation after significant intrauterine injury.

Intraoperative angiography during minimally invasive direct coronary artery bypass operations.

BACKGROUND: The technical demands of beating heart operations raise concerns about anastomotic patency. This feasibility study tested the usefulness of intraoperative angiography during minimally invasive direct coronary artery bypass grafting (MIDCABG). METHODS: Ten patients underwent intraoperative angiography of the internal thoracic artery (ITA) after MIDCABG. Minimally invasive direct coronary artery bypass grafting was performed on a beating heart through the fourth or fifth intercostal space. Angiography was performed through the right or left femoral artery with a 7F introducer system placed before the operation. Views were obtained in the right and left anterior oblique and straight anterior projections. RESULTS: There were no deaths or intraoperative morbidities related to MIDCABG or angiography. Seven patients demonstrated widely patent MIDCABG anastomoses with obliteration of all intercostals, widely patent ITA pedicles, good distal runoff, and placement of the ITA into the proper native coronary artery. Two patients had revisions of their ITA pedicles, which on repeated angiography showed correction. One patient's procedure was converted to a sternotomy because of poor distal runoff and haziness at the level of the MIDCABG anastomosis. CONCLUSIONS: This feasibility study demonstrates the utility of intraoperative ITA angiography in identifying problems after MIDCABG. Intraoperative angiography may facilitate MIDCABG by documenting proper placement of conduits, obliteration of intercostal vessels, and patency of the MIDCABG anastomosis and ITA pedicle.

Hypotension after blunt abdominal trauma: the role of emergent abdominal sonography in surgical triage.

OBJECTIVE: Trauma victims with hypotension require a rapid and reliable localization of bleeding and expedient surgical triage. Our hypothesis is that emergent abdominal sonography (EAS) is a rapid and accurate test of the need for urgent laparotomy in blunt trauma victims with hypotension. METHODS: Among 400 blunt trauma victims entered in a prospective blind study of EAS, a subgroup of 69 (17%) patients had a systolic blood pressure < or = 90 mm Hg during their initial assessment. Although the EAS results [(+) = fluid, (-) = no fluid] were not used in clinical decision making, the potential contribution of EAS to patient care was examined. RESULTS: The mean Injury Severity Score was 32. Twenty-two (32%) patients were EAS (+), of which 19 required an acute laparotomy. No laparotomies were performed in the 47 EAS (-) patients. The EASs required 19 +/- 5 seconds in the EAS (+) group and 154 +/- 13 seconds in the EAS (-) group. Twenty of the 22 positive EASs had free fluid in Morison's pouch. All 13 patients with an ultrasound score > or = 3 had a laparotomy. The primary etiology of hypotension was blood loss in 42 patients, hemoperitoneum in 18, and retroperitoneal hemorrhage in 12. CONCLUSION: EAS is a rapid and accurate indicator of the need for urgent laparotomy in the hypotensive blunt trauma victim. Further, a negative EAS can hasten the search for other causes of hypotension. Diagnostic peritoneal lavage may become obsolete in centers with EAS capabilities.

Injury pattern and severity in lateral motor vehicle collisions: a Canadian experience.

OBJECTIVE: To determine the pattern and severity of injury and the outcome of front seat motor vehicle occupants after lateral impact crashes. DESIGN: Retrospective review undertaken in a Regional Trauma Unit (Sunnybrook Health Science Centre). MATERIALS AND METHODS: Review of seriously injured front seat motor vehicle occupants admitted to a Regional Trauma Unit over a 46-month period (September 15, 1989, to July 15, 1993) for whom vehicle crash information and occupant seat belt use were known. MEASUREMENTS AND MAIN RESULTS: Three hundred forty-eight front seat vehicle occupants were available for study; one hundred forty-one (41%) were involved in a lateral impact motor vehicle crash. Driver side lateral crashes (57%) were more common than passenger side impacts. Victims of lateral impact crashes had a significantly higher mean Injury Severity Score (25 compared with 20 for nonlateral crashes: p < 0.05), and the direction of impact was strongly associated with injury severity (p < 0.05). Lateral impact crashes resulted in substantially more significant chest (p < 0.01) and intra-abdominal (p < 0.0001) injuries. Type of injury was significantly different between the lateral and nonlateral impact groups for facial, chest, abdominal, and musculoskeletal injuries. CONCLUSIONS: The direction of impact in motor vehicle crashes is strongly associated with the pattern and severity of organ injuries. Further attention to automobile safety design is necessary to better protect occupants involved in lateral impact crashes.

Emergent abdominal sonography as a screening test in a new diagnostic algorithm for blunt trauma.

Although there is an interest in emergent abdominal sonography (EAS), the clinical utilization of EAS in North America is minimal. The purpose of this study was to develop a new diagnostic algorithm for blunt abdominal injury based on a prospective blinded comparison of EAS, diagnostic peritoneal lavage (DPL), and computed tomography (CT). EAS (+ = fluid, - = no fluid) was performed before the DPL or CT, in 400 patients with a mean Injury Severity Score of 26; 293 had a CT and 107 had a DPL. The EASs required 2.6 +/- 1.2 minutes with 82% < or = 3 minutes. The accuracy of EAS for free fluid was 94% with a positive and negative predictive value of 82 and 96%, respectively. Only 1 of 338 patients with EAS- had an acute therapeutic laparotomy. Three patients with EAS- had a delayed laparotomy based on evolving clinical findings. The radiologists interpretation of the EAS video disagreed with the clinician sonographer in only 3% of cases. Based on these results, a diagnostic algorithm was developed using EAS as a screening test with selective use of DPL and CT. Emergent abdominal sonography performed by clinician sonographers is a rapid and accurate test for peritoneal fluid in blunt trauma victims, and the need for laparotomy in patients with a negative EAS is rare. Our study supports the routine use of EAS as a screening test in a diagnostic algorithm for the evaluation of blunt abdominal trauma.