Surgery induces human mononuclear cell arginase I expression.

BACKGROUND: Arginase is a metabolic enzyme for the amino acid arginine that participates in the immune response to trauma. We hypothesize that surgical trauma induces arginase expression and activity in the human immune system. METHODS: Peripheral mononuclear cell (MNC) arginase activity and expression and plasma nitric oxide metabolites and interleukin (IL)-10 were measured in patients undergoing elective general surgery. Twenty-two healthy volunteers served as a comparison population. RESULTS: MNC arginase activity increased within 6 hours of surgery (p < 0.05) and coincided with increased arginase I protein expression. Plasma nitric oxide metabolites decreased significantly postoperatively (p < 0.05). Patients lacking an elevation in IL-10 failed to demonstrate increased MNC arginase activity. CONCLUSION: Increased MNC arginase expression may contribute to postsurgical immune dysfunction by affecting arginine use and availability and nitric oxide metabolism in the immune system. Plasma IL-10 may play a role in regulating MNC arginase activity.

The routine use of sonography in penetrating torso injury is beneficial.

BACKGROUND: Torso sonography (focused assessment with sonography for trauma [FAST]) has been added to our protocols for the evaluation of penetrating torso injury. The purpose of this study was to evaluate our recent experience and determine whether the use of FAST is beneficial. METHODS: From January 1999 to January 2000, patients with penetrating torso injury and no clinical indication for surgery were evaluated by sonography with a selective use of other investigations. FAST consisted of sonographic views of the peritoneum and/or pericardium to determine the presence or absence of fluid. RESULTS: During the study period, there were 238 victims of penetrating injury assessed by our trauma service, and sonography was performed in 72 (30%) patients as per our protocols. There were 31 stab, 37 gunshot/shotgun and, and 4 puncture wounds. Thirty-eight patients had peritoneal views, 6 patients had pericardial views, and 28 patients had both pericardial and peritoneal views obtained. Thirteen of 66 patients had free fluid in the peritoneal cavity and 12 of the 13 patients had a therapeutic laparotomy. No peritoneal fluid was seen in 53 of 66 patients, of whom 6 had abdominal injuries, 5 requiring surgery for diaphragm or bowel injuries. The sensitivity of FAST alone for abdominal injury was 67%, specificity was 98%, positive predictive value was 92%, and negative predictive value was 89%. Pericardial fluid was seen in 3 of 34 patients; one had a heart wound and two had negative pericardial windows. All 31 patients without pericardial fluid recovered without surgery. CONCLUSION: The routine use of sonography in penetrating torso injury is beneficial. The detection of pericardial or peritoneal fluid is clinically useful. However, a negative FAST examination does not exclude abdominal injury, such as a diaphragm or hollow viscus wound, and further investigation or close follow-up is required.

Blunt abdominal aortic trauma in association with thoracolumbar spine fractures.

All patients with blunt abdominal aortic disruption (BAAD) in the trauma registries at the three Regional Trauma Centres were retrospectively reviewed over the last decade. From the 11465 trauma admissions ISS>16,194 sustained aortic injuries. Eight cases of BAAD were identified, six with concurrent thoracolumbar spine (TLS) fractures (mean ISS 42). Patients with BAAD and TLS were subject to a detailed analysis. Clinically, three injury types were seen, hemodynamically unstable (uncontained full thickness laceration), stable symptomatic (intimal dissection with occlusion), and stable asymptomatic (contained full thickness laceration or intimal dissection without occlusion). All spinal column fractures involved a distractive mechanism, one with both distractive and translational fracture components. We propose that a distractive force, applied to the aorta lying anterior to the anterior longitudinal ligament, results in an aortic injury spectrum ranging from an intimal tear to a full thickness laceration, as a related injury. Computed tomography (CT) was an important imaging modality in the stable asymptomatic patients. All intimal dissections without occlusion were managed non-operatively. With distractive TLS fractures, BAAD needs to be considered.

Alterations in arginine metabolic enzymes in trauma.

Arginine is the sole substrate for nitric oxide (NO) synthesis by NO synthases (NOS) and promotes the proliferation and maturation of human T-cells. Arginine is also metabolized by the enzyme arginase, producing urea and ornithine, the precursor for polyamine production. We sought to determine the molecular mechanisms regulating arginase and NOS in splenic immune cells after trauma. C3H/HeN mice underwent laparotomy as simulated moderate trauma or anesthesia alone (n = 24 per group). Six, 12, 24, or 48 h later, 6 animals from each group were sacrificed, and splenectomy was performed and plasma collected. Six separate animals had neither surgery nor anesthesia and were sacrificed to provide resting values (t = 0 h). Spleen arginase I and II and iNOS mRNA abundance, arginase I protein expression, and arginase activity were determined. Plasma NO metabolites (nitrite + nitrate) were also measured. Trauma increased spleen arginase I protein expression and activity (P = 0.01) within 12 and for at least 48 h after injury and coincided with up-regulated arginase I mRNA abundance at 24 h. Neither arginase II nor iNOS mRNA abundance in the spleen was significantly increased by trauma at 24 h. Plasma nitrite + nitrate was decreased in animals 48 h post-injury compared to anesthesia controls (P < 0.05). Trauma induces up-regulation of arginase I gene expression in splenic immune cells within 24 h of injury. Arginase II is not significantly up-regulated at that time point. Arginase I, rather than iNOS appears to be the dominant route for arginine metabolism in splenic immune cells 24 h after trauma.

Arginase I expression and activity in human mononuclear cells after injury.

OBJECTIVE: To determine the effect of trauma on arginase, an arginine-metabolizing enzyme, in cells of the immune system in humans. SUMMARY BACKGROUND DATA: Arginase, classically considered an enzyme exclusive to the liver, is now known to exist in cells of the immune system. Arginase expression is induced in these cells by cytokines interleukin (IL) 4, IL-10, and transforming growth factor beta, corresponding to a T-helper 2 cytokine profile. In contrast, nitric oxide synthase expression is induced by IL-1, tumor necrosis factor, and gamma interferon, a T-helper 1 cytokine profile. Trauma is associated with a decrease in the production of nitric oxide metabolites and a state of immunosuppression characterized by an increase in the production of IL-4, IL-10, and transforming growth factor beta. This study tests the hypothesis that trauma increases arginase activity and expression in cells of the immune system. METHODS: Seventeen severely traumatized patients were prospectively followed up in the intensive care unit for 7 days. Twenty volunteers served as controls. Peripheral mononuclear cells were isolated and assayed for arginase activity and expression, and plasma was collected for evaluation of levels of arginine, citrulline, ornithine, nitrogen oxides, and IL-10. RESULTS: Markedly increased mononuclear cell arginase activity was observed early after trauma and persisted throughout the intensive care unit stay. Increased arginase activity corresponded with increased arginase I expression. Increased arginase activity coincided with decreased plasma arginine concentration. Plasma arginine and citrulline levels were decreased throughout the study period. Ornithine levels decreased early after injury but recovered by postinjury day 3. Increased arginase activity correlated with the severity of trauma, early alterations in lactate level, and increased levels of circulating IL-10. Increased arginase activity was associated with an increase in length of stay. Plasma nitric oxide metabolites were decreased during this same period. CONCLUSIONS: Markedly altered arginase expression and activity in cells of the human immune system after trauma have not been reported previously. Increased mononuclear cell arginase may partially explain the benefit of arginine supplementation for trauma patients. Arginase, rather than nitric oxide synthase, appears to be the dominant route for arginine metabolism in immune cells after trauma.

Utilization of FAST (Focused Assessment with Sonography for Trauma) in 1999: results of a survey of North American trauma centers.

Although much has been written about FAST (Focused Assessment with Sonography for Trauma) in the last decade little is known about its present clinical utilization. The purpose of this study was to evaluate and characterize the contemporary utilization of FAST at trauma centers in the United States and Canada. In 1999 trauma directors or their delegates at Level I regional trauma centers in the United States and Canada were surveyed either by fax or phone regarding the present utilization and the future of FAST at their center. The overall survey response rate was 91 per cent with 96 of 105 centers completing the survey. Of the 96 centers surveyed 78 were in the United States and 18 were in Canada. Of the 78 U.S. centers surveyed 62 (79%) routinely use FAST, and it is done by surgeons in 39 per cent, surgeons and emergency departments in 21 per cent, emergency departments in 5 per cent, and radiologists in 35 per cent. Most centers (79%) thought that it sped up their workups, and 89 per cent said it was an advance in patient care. FAST is used in penetrating injury at 58 per cent of centers, and some centers use FAST to assess organ injury. The utilization of diagnostic peritoneal lavage and CT has markedly decreased at many centers. Almost all respondents thought that FAST should be a component of surgery resident training. The utilization of FAST is significantly less in Canada than in the United States (P < 0.05). Our conclusions are the following. FAST has become routinely used at the majority of the U.S. centers surveyed. FAST is performed by clinicians at 65 per cent of the trauma centers surveyed. The utilization of CT and diagnostic peritoneal lavage has changed. Many centers have broadened the scope of FAST to include the assessment of organ, pediatric, and penetrating injury.

Is clinical examination an accurate indicator of raised intra-abdominal pressure in critically injured patients?

OBJECTIVES: To determine the rate of elevated intra-abdominal pressure (IAP) and to evaluate the accuracy of clinical abdominal examination in the assessment of IAP in the critically injured trauma patient. DESIGN: A prospective blinded study. SETTING: The medical-surgical critical care unit of a university-affiliated regional adult trauma centre. PATIENTS: Forty-two adult blunt trauma victims, who had a mean injury severity score of 36. INTERVENTIONS: Urinary bladder pressure was measured daily and classified as normal (10 mm Hg or less), elevated (more than 10 mm Hg) or significantly elevated (more than 15 mm Hg). A blinded clinical assessment of abdominal pressure was concurrently performed and recorded as elevated or normal. MAIN OUTCOME MEASURES: The sensitivity, specificity and accuracy and the positive and negative predictive values of the 2 interventions in identifying elevated IAP. RESULTS: Twenty-one patients (50%) had an elevated IAP at some point during the study. Of the 147 bladder pressure measurements done in these 42 patients, 47 (32%) were more than 10 mm Hg and 16 (11%) were more than 15 mm Hg. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of clinical abdominal examination for identifying elevated IAP were 40%, 94%, 76%, 77% and 77%, respectively. Clinical abdominal examination had a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 56%, 87%, 35%, 94% and 84% respectively, for significantly elevated IAP. CONCLUSIONS: Urinary bladder pressure was commonly elevated among our population of critically injured adults. Compared with bladder pressure measurements, clinical abdominal assessment showed poor sensitivity and accuracy for elevated IAP. These findings suggest that more routine measurements of bladder pressure in patients at risk for intra-abdominal hypertension should be performed.

A single-center 8-year experience with percutaneous dilational tracheostomy.

OBJECTIVE: To determine surgical, postoperative, and postdischarge complications associated with percutaneous dilational tracheostomy (PDT) in an 8-year experience at the University of Kentucky. SUMMARY BACKGROUND DATA: There are known risks associated with the transport of critically ill patients to the operating room for elective tracheostomy, and less-than-optimal conditions may interfere with open bedside tracheostomy. PDT has been introduced as an alternative to open tracheostomy. Despite information supporting its safety and utility, the technique has been criticized because advocates had not provided sufficient information regarding complications. METHODS: A prospective database was initiated on all patients who underwent PDT between September 1990 and May 1998. The database provided indication, procedure time, duration of intubation before PDT, and intraoperative and postoperative complications. Retrospective review of medical records and phone interviews provided long-term follow-up information. RESULTS: In the 8-year period, 827 PDTs were performed in 824 patients. Two patients were excluded because PDT could not be completed for technical reasons. There were 519 male and 305 female patients. Mean age was 56 years. Prolonged mechanical ventilatory support was the most common indication. Mean procedure time was 15 minutes, and the average duration of intubation before PDT was 10 days. The intraoperative complication rate was 6%, with premature extubation the most common complication. The procedure-related death rate was 0.6%. Postoperative complications were found in 5%, with bleeding the most common. With a mean follow-up of greater than 1 year, the tracheal stenosis rate was 1.6%. CONCLUSIONS: On the basis of this large, single-center study, the authors conclude that when performed by experienced surgeons, PDT is a safe and effective alternative to open surgical tracheostomy for intubated patients who require elective tracheostomy.

A minimally invasive approach to bile peritonitis after blunt liver injury.

The advent of nonoperative management of liver injuries has made it imperative that surgeons be familiar with the potential delayed complications of this approach. In this report, we describe a minimally invasive strategy for the management of bile peritonitis following nonoperative management of blunt liver injuries. Two cases are presented in which bile peritonitis with massive bile ascites was managed with laparoscopic localization and drainage of the bile leak, irrigation of the peritoneal cavity, and postoperative endoscopic retrograde cholangiography with bile duct stenting. In both cases the bile leak ceased, and the patients recovered without adverse sequelae. The combination of laparoscopic surgery and endoscopic stenting provides a minimally invasive approach to this entity.

Beta adrenoceptor regulation of macrophage arginase activity.

BACKGROUND: Arginase, which metabolizes L-arginine within the urea cycle, is essential for production of polyamines and affects production of nitric oxide by depletion of L-arginine, the common substrate for both arginase and nitric oxide synthase. Having shown that trauma increases splenic macrophage arginase activity, we seek to define the mechanisms for this. RAW macrophage arginase activity and expression are increased by 8-bromo-cAMP in vitro. We hypothesize that since catecholamines increase cAMP, trauma-induced splenic arginase activity may be mediated by post-injury catecholamine release. METHODS: RAW 264.7 macrophage arginase activity was measured in vitro in response to 4 catecholamines with or without propranolol or lipopolysaccharide (LPS). C57BL/6 mice underwent laparotomy as a model of moderate trauma after propranolol treatment, with and without intraperitoneal Escherichia coli LPS administration as a simulated pro-inflammatory stimulus. RESULTS: Macrophage arginase activity increased in vitro in response to catecholamines or LPS (P < .05). Propranolol pretreatment blocked macrophage arginase activity induced by epinephrine (10 mumol/L) in vitro (P < .05). Trauma or LPS alone increased splenic arginase activity in vivo (P < .05). Propranolol did not alter LPS-induced splenic arginase activity but did significantly reduce trauma-induced splenic arginase activity (P < .05). CONCLUSIONS: Catecholamines alone increase macrophage arginase activity through beta-adrenoceptor activation. Increased splenic arginase activity induced by moderate trauma is decreased by beta-adrenoceptor blockade, suggesting that trauma-induced arginase activity is partly mediated by endogenous catecholamines.

Trauma increases extrahepatic arginase activity.

BACKGROUND: Although expressed primarily in the liver, arginase activity also is present in extrahepatic tissues and specifically in macrophages, where it may play diverse physiologic roles in wound healing, cellular proliferation, and the regulation of nitric oxide production. Arginase activity in immune cells is upregulated by certain cytokines such as IL-4, IL-10, and TGF-beta and by catecholamines. Since the release of these substances is increased after trauma, we hypothesized that arginase activity would also be increased in immune cells after trauma. The current work tests this hypothesis. METHODS: A model of surgical trauma was created in C3H/HeN mice by performing an exploratory laparotomy. Tissue arginase activity and arginase I protein expression were determined. As a control, arginase activity and expression were also stimulated with the use of endotoxin. In addition, we evaluated the expression of inducible nitric oxide synthase and the accumulation of nitric oxide metabolites in plasma. RESULTS: Surgical trauma was associated with a significant increase in arginase activity in splenic and renal tissues (P < .05). Splenic macrophages from trauma animals exhibited arginase activity levels approximately 10 times those of controls (P < .05). Endotoxin alone increased arginase activity in the spleen, but this increase was less than that of trauma alone (P < .05). Arginase activity remained elevated after trauma for up to 4 days and normalized by day 7. Arginase I expression was upregulated by trauma in both splenic and renal tissue and by endotoxin in the spleen only. Despite upregulation of inducible nitric oxide synthase in trauma animals, circulating nitric oxide metabolites were decreased 2 days after trauma compared with controls (P < .05). Endotoxin-induced nitric oxide metabolites were also reduced in trauma animals compared with endotoxin treatment alone (P < .05), but this normalized by day 4. CONCLUSIONS: Extrahepatic arginase expression and activity is increased after trauma and may provide the necessary precursors for cellular proliferation and repair or may play a regulatory role in the production of nitric oxide.

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.

Prospective evaluation of the potential role of teleradiology in acute interhospital trauma referrals.

BACKGROUND: Teleradiology is one form of telemedicine that would allow the transmission of radiographs before the transfer of acutely traumatized patients between referring and receiving hospitals. The purpose of this study was to evaluate the potential impact of a prehospital teleradiology system on trauma patient management and transfer. METHODS: Forty-four injured adults referred to a trauma center were included. The history, physical examination, and radiographic findings reported by the referring physician to the receiving physician were documented. The plain radiographs of the chest, pelvis, and cervical spine taken at the referring hospital were obtained after patient transfer. For each case, two reviewers blinded to the case (surgeon [S] and emergency department physician [E]) and one reviewer not blinded to the case were individually presented with the referring physician's report and the radiographs. The reviewers were surveyed as to the implications of viewing the plain radiographs taken at the referring hospital before patient transfer. RESULTS: Overall, the blinded reviewers felt that viewing the radiographs before transfer would have influenced care in 40% and 38% of cases as judged by (S) and (E), respectively, with a crude agreement of 67.5% (kappa level, 0.32). The blinded reviewers (S and E) commonly noted the following four changes in management as a result of viewing the referred radiographs: requested further clinical history (S, 18%; E, 23%), suggested further pretransfer interventions (S, 38%; E, 30%), suggested further pretransfer diagnostic tests (S, 25%; E, 13%), and emphasized precautions during transfer (S, 28%; E, 30%). The nonblinded reviewer suggested potential influence in the management of at least 65% of the cases. CONCLUSION: This study suggests that viewing the radiographs of acutely injured trauma patients has the potential to influence many aspects of the management of interhospital transfer.

Sonographic assessment of traumatic injury. Future developments.

In all its forms and applications, sonography plays a significant role in the management of injured patients, from the emergency department to beyond hospital discharge. The use of new and existing sonographic technology will increase because sonographic imaging and measurements are generally less invasive; are inexpensive; use no ionizing radiation; and are portable, repeatable, and, in many instances, as accurate as the so-called "contemporary gold standards." The training and credentialing of physicians in sonography is in evolution and will be an increasingly important issue with more widespread use and broader applications. The future of sonography in trauma care in the next millennium is bright, and surgeons and surgical residents are encouraged to gain proficiency and learn about this new surgical frontier as it evolves.

Early detection of hemoperitoneum by ultrasound examination of the right upper quadrant: a multicenter study.

BACKGROUND: The focused assessment for the sonographic examination of the trauma patient (FAST) is a rapid diagnostic test that sequentially surveys for hemopericardium and then the right upper quadrant (RUQ), left upper quadrant (LUQ), and pelvis for hemoperitoneum in patients with potential truncal injuries. The sequence of the abdominal part of the examination, however, has yet to be validated. The objectives of this multicenter study were as follows: (1) to determine where hemoperitoneum is most frequently identified on positive FAST examinations; and (2) to determine if a relationship exists between that areas and the organs injured. METHODS: Ultrasound registries from four Level I trauma centers identified patients who had true-positive FAST examinations. Demographic data, areas positive on the FAST, and organs injured were recorded; injuries were classified as multiple, single solid organ (liver or spleen), isolated hollow viscus, or retroperitoneal. Relationships between positive locations on the FAST examinations and the associations of organs injured to areas positive were assessed using McNamara's chi2 test; a p value < 0.05 was considered statistically significant. RESULTS: The RUQ was the most common site where hemoperitoneum was detected, and this was statistically significant compared with either the LUQ or the pelvis. Also, statistically significant correlations (p < 0.001) were observed between positive RUQ areas on the FAST and multiple injuries, single solid organ (liver or spleen) injury, and retroperitoneal injuries. CONCLUSION: Blood is most often found on the FAST in the RUQ area in patients with multiple intraperitoneal injuries or isolated injury to the liver, spleen, or retroperitoneum, but not when there is injury to a hollow viscus.

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.

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.