Andrew B. Peitzman

Nitrogen oxide levels in patients after trauma and during sepsis.

The mediators responsible for maintenance of the hyperdynamic state and the low systemic vascular resistance (SVR) observed in sepsis have not been elucidated. Nitric oxide (.N = O) is a mediator with numerous functions, including regulation of vascular tone and a role in macrophage-mediated cytostasis and microbiostasis. Thirty-nine critically ill trauma and septic patients were studied to determine the relationship between .N = O production and the hyperdynamic state. high plasma levels of NO2-/NO3- (the stable end products of .N = O) were observed in septic patients (p less than 0.02). Low SVR and high endotoxin levels were associated with high NO2-/NO3- values (p = 0.029, p = 0.002). Changes in .N = O levels may mediate the vasodilation seen in sepsis. Low NO2-/NO3- levels were observed in trauma patients (p less than 0.001) and remained low even in the presence of sepsis (p = 0.001).

Blunt splenic injury in adults: Multi-institutional study of the Eastern Association for the Surgery of Trauma

BACKGROUND Nonoperative management of blunt injury to the spleen in adults has been applied with increasing frequency. However, the criteria for nonoperative management are controversial. The purpose of this multi-institutional study was to determine which factors predict successful observation of blunt splenic injury in adults. METHODS A total of 1,488 adults (>15 years of age) with blunt splenic injury from 27 trauma centers in 1997 were studied through the Multi-institutional Trials Committee of the Eastern Association for the Surgery of Trauma. Statistical analysis was performed with analysis of variance and extended chi2 test. Data are expressed as mean +/- SD; a value of p < 0.05 was considered significant. RESULTS A total of 38.5 % of patients went directly to the operating room (group I); 61.5% of patients were admitted with planned nonoperative management. Of the patients admitted with planned observation, 10.8% failed and required laparotomy; 82.1% of patients with an Injury Severity Score (ISS) < 15 and 46.6% of patients with ISS > 15 were successfully observed. Frequency of immediate operation correlated with American Association for the Surgery of Trauma (AAST) grades of splenic injury: I (23.9%), II (22.4%), III (38.1%), IV (73.7%), and V (94.9%) (p < 0.05). Of patients initially managed nonoperatively, the failure rate increased significantly by AAST grade of splenic injury: I (4.8%), II (9.5%), III (19.6%), IV (33.3%), and V (75.0%) (p < 0.05). A total of 60.9% of the patients failed nonoperative management within 24 hours of admission; 8% failed 9 days or later after injury. Laparotomy was ultimately performed in 19.9% of patients with small hemoperitoneum, 49.4% of patients with moderate hemoperitoneum, and 72.6% of patients with large hemoperitoneum. CONCLUSION In this multicenter study, 38.5% of adults with blunt splenic injury went directly to laparotomy. Ultimately, 54.8% of patients were successfully managed nonoperatively; the failure rate of planned observation was 10.8%, with 60.9% of failures occurring in the first 24 hours. Successful nonoperative management was associated with higher blood pressure and hematocrit, and less severe injury based on ISS, Glasgow Coma Scale, grade of splenic injury, and quantity of hemoperitoneum.

An FFP: PRBC transfusion ratio >/=1:1.5 is associated with a lower risk of mortality after massive transfusion.

OBJECTIVE The detrimental effects of coagulopathy, hypothermia, and acidosis are well described as markers for mortality after traumatic hemorrhage. Recent military experience suggests that a high fresh frozen plasma (FFP):packed red blood cell (PRBC) transfusion ratio improves outcome; however, the appropriate ratio these transfusion products should be given remains to be established in a civilian trauma population. METHODS Data were obtained from a multicenter prospective cohort study evaluating clinical outcomes in blunt injured adults with hemorrhagic shock. Those patients who required >/=8 units PRBCs within the first 12 hours postinjury were analyzed (n = 415). RESULTS Patients who received transfusion products in >/=1:1.50 FFP:PRBC ratio (high F:P ratio, n = 102) versus <1:1.50 FFP:PRBC ratio (low F:P, n = 313) required significantly less blood transfusion at 24 hours (16 +/- 9 units vs. 22 +/- 17 units, p = 0.001). Crude mortality differences between the groups did not reach statistical significance (high F:P 28% vs. low F:P 35%, p = 0.202); however, there was a significant difference in early (24 hour) mortality (high F:P 3.9% vs. low F:P 12.8%, p = 0.012). Cox proportional hazard regression revealed that receiving a high F:P ratio was independently associated with 52% lower risk of mortality after adjusting for important confounders (HR 0.48, p = 0.002, 95% CI 0.3-0.8). A high F:P ratio was not associated with a higher risk of organ failure or nosocomial infection, however, was associated with almost a twofold higher risk of acute respiratory distress syndrome, after controlling for important confounders. CONCLUSIONS In patients requiring >/=8 units of blood after serious blunt injury, an FFP:PRBC transfusion ratio >/=1:1.5 was associated with a significant lower risk of mortality but a higher risk of acute respiratory distress syndrome. The mortality risk reduction was most relevant to mortality within the first 48 hours from the time of injury. These results suggest that the mortality risk associated with an FFP:PRBC ratio <1:1.5 may occur early, possibly secondary to ongoing coagulopathy and hemorrhage. This analysis provides further justification for the prospective trial investigation into the optimal FFP:PRBC ratio required in massive transfusion practice.

Impact of pediatric trauma centers on mortality in a statewide system.

Background: Regional pediatric trauma centers (PTC) were established to optimize the care of injured children. However, because of the relative shortage of PTC, many injured children continue to be treated at adult trauma centers (ATC). As a result, a growing controversy has evolved regarding the impact of PTC and ATC on outcome for injured children. Methods: A retrospective analysis of 13,351 injured children entered in the Pennsylvania Trauma Outcome Study between 1993 and 1997 was conducted. Patients were stratified according to mechanism of injury, injury severity, specific organ injury, and type of trauma center: PTC; Level I ATC (ATC I); Level II ATC (ATC II); or ATC with added qualifications to treat children (ATC AQ). Mortality was the major outcome variable measured. Results: Most injured children were treated at a PTC or ATC AQ. The majority of children below 10 years of age were admitted to PTC. Patients treated at PTC and ATC had similar injury severity as determined by median Injury Severity Score, mean Revised Trauma Score, and Glasgow Coma Scale. Overall survival was significantly better at PTC and ATC AQ compared with ATC I and ATC II. Survival for head, spleen, and liver injuries was significantly better at PTC compared with ATC AQ, ATC I, or ATC II. Children who sustained moderate or severe head injuries were more likely to undergo neurosurgical intervention and have a better outcome when treated at a PTC. Despite similar mean Abbreviated Injury Scores for spleen and liver, significantly more children underwent surgical exploration (especially splenectomy) for spleen and liver injuries at ATC compared with PTC. Conclusion: Children treated at PTC or ATC AQ have significantly better outcome compared with those treated at ATC. Severely injured children (Injury Severity Score > 15) with head, spleen, or liver injuries had the best overall outcome when treated at PTC. This difference in outcome may be attributable to the approach to operative and nonoperative management of head, liver, and spleen injuries at PTC.

Fresh frozen plasma is independently associated with a higher risk of multiple organ failure and acute respiratory distress syndrome.

BACKGROUND Blood transfusion is known to be an independent risk factor for mortality, multiple organ failure (MOF), acute respiratory distress syndrome (ARDS), and nosocomial infection after injury. Less is known about the independent risks associated with plasma-rich transfusion components including fresh frozen plasma (FFP), platelets (PLTS), and cryoprecipitate (CRYO) after injury. We hypothesized that plasma-rich transfusion components would be independently associated with a lower risk of mortality but result in a greater risk of morbid complications. METHODS Data were obtained from a multicenter prospective cohort study evaluating clinical outcomes in bluntly injured adults with hemorrhagic shock. All patients required blood transfusion for enrollment. Patients with isolated traumatic brain injury and those not surviving beyond 48 hours were excluded. Cox proportional hazard regression models were used to estimate the outcome risks (per unit) associated with plasma-rich transfusion requirements during the initial 24 hours after injury after controlling for important confounders. RESULTS For the entire study population (n = 1,175), 65%, 41%, and 28% of patients received FFP, PLTS and CRYO, respectively. There was no association with plasma-rich transfusion components and mortality or nosocomial infection. For every unit given, FFP was independently associated with a 2.1% and 2.5% increased risk of MOF and ARDS, respectively. CRYO was associated with a 4.4% decreased risk of MOF (per unit), and PLTS were not associated with any of the outcomes examined. When early deaths (within 48 hours) were included in the model, FFP was associated with a 2.9% decreased risk of mortality per unit transfused. CONCLUSIONS In patients who survive their initial injury, FFP was independently associated with a greater risk of developing MOF and ARDS, whereas CRYO was associated with a lower risk of MOF. Further investigation into the mechanisms by which these plasma-rich component transfusions are associated with these effects are required.

Admission hypothermia and outcome after major trauma.

Objective:Uncontrolled exposure hypothermia is believed to be deleterious in the setting of major trauma. Prevention of hypothermia in the injured patient is currently practiced in both prehospital and in-hospital settings. However, this standard is based on studies of limited patient series that were not designed to identify the independent relationship between hypothermia and mortality. Recent studies suggest that therapeutically applied hypothermia may benefit selected patient subsets. The goal of this study was to evaluate the independent association between admission hypothermia and mortality after major trauma, with adjustment for clinical confounders. Design:Retrospective analysis of a statewide trauma registry. The primary outcome was death at hospital discharge. The key exposure was hypothermia, defined as body temperature ≤35°C at admission. Multivariate regression was used to risk-adjust for age, severity and mechanism of injury, and route of temperature measurement. Additional adjustment for prehospital exposure time and intravenous fluid therapy was also evaluated. Setting:Trauma centers of the Commonwealth of Pennsylvania. Patients:All trauma patients ≥16 yrs of age for the years 2000–2002. Transferred patients were excluded. Patients were excluded if temperature or route of temperature measurement was not known. Both the full cohort and a subset with isolated severe head injury were evaluated. Interventions:None. Measurements and Main Results:Of 38,520 patients, 1,921 (5.0%) were hypothermic at admission. Admission hypothermia was independently associated with increased odds of death in both the full cohort (odds ratio, 3.03; 95% confidence interval, 2.62–3.51) and the subset with isolated severe head injury (2.21; 1.62–3.03), with adjustment for age, severity and mechanism of injury, and route of temperature measurement. Conclusions:Admission hypothermia is independently associated with increased adjusted odds of death after major trauma. The increase in mortality is not completely attributable to physiologic presentation or injury pattern or severity.

Bacterial translocation in trauma patients.

Sepsis and multiple system organ failure (MSOF) are major causes of morbidity and mortality in trauma patients. Bacterial translocation induced by hypotension, endotoxemia, or burns is a reproducible phenomenon in the laboratory. The incidence of bacterial translocation to mesenteric lymph nodes (MLNs) in 29 critically ill patients was evaluated to determine its relationship to subsequent sepsis and MSOF. Bacterial translocation was documented in 3 of 4 patients who underwent laparotomy for gastrointestinal (GI) disease. No trauma patient (25 patients), even at second exploration 3-5 days after injury, had a positive MLN culture. Five patients died; 4 trauma patients, one with GI disease. Forty percent of the trauma patients had major complications, predominantly pulmonary infections with gram-negative bacteria. However, infectious complications and outcome were not related to MLN culture results. The classical progression of bacteria from the gut to the bloodstream via the MLNs may require time and gut mucosal injury. The data suggest that bacterial translocation to the MLNs is not a common occurrence in acutely injured trauma patients.

Percutaneous iliosacral screw fixation : early treatment for unstable posterior pelvic ring disruptions

OBJECTIVE Open reduction and internal fixation of unstable posterior pelvic ring injury provides better bony stability and less long term morbidity than nonoperative treatment. However, open reduction and internal fixation of the posterior pelvis may involve substantial intraoperative blood loss, reported infection rates of 6 to 25%, and wound complications in 25%. Our hypothesis was that percutaneous cannulated iliosacral screws placed by fluoroscopic control would provide early, rapid, definitive stabilization with minimal blood loss, infection, and wound complications. DESIGN A retrospective medical record and radiographic study. MATERIALS, METHODS, MEASUREMENTS AND MAIN RESULTS: Twenty consecutive patients with an unstable posterior pelvic ring injury treated by percutaneous fixation (41 screws) under fluoroscopic guidance were reviewed. Average patient age was 34 years, trauma score was 14.4 +/- 3.3, and Injury Severity Score was 22.9 +/- 10.6. Mechanisms were motor vehicle collisions (11), falls (3), crush injury (3), and pedestrian/auto (3). Pelvic injuries were classified as Tile B (5) or Tile C (15). Associated injuries were present in 80%. Seventy-five percent of patients underwent pelvic fixation less than 72 hours after injury with closed percutaneous screw placement achieved in 60%, assisted by open reduction in 25% or aided by anterior external fixation in 15%. Mean operative time was 52 minutes for patients requiring percutaneous screws only (7 of 20 patients, 35%), whereas average blood loss was 233 mL for all cases (including open anterior and posterior procedures). No loss of fixation or wound complications occurred during 9.6 months follow-up. CONCLUSIONS Percutaneous iliosacral screw fixation for unstable posterior pelvic disruption provided early fixation with minimal operative time, minimal blood loss, and wound-related morbidity.

The acute management of hemodynamically unstable multiple trauma patients with pelvic ring fractures.

The management of hemodynamically unstable patients with displaced pelvic ring fractures and associated abdominal, thoracic, or head injuries is controversial. We studied 312 consecutive trauma patients with pelvic fractures admitted from July 1, 1989 through June 30, 1993: thirty-six of these patients were in shock (SBP < or = 90 mm Hg) and were treated by a protocol including volume resuscitation, and treatment of the associated injuries, without use of acute external fixation. Evaluation of the pelvic fractures revealed 39% to be rotationally unstable; 61% were both rotationally and vertically unstable. The mean injury Severity Score was 27 +/- 12, the average Glasgow Coma Scale score was 12 +/- 5, and the Abbreviated Injury Scale (AIS) scores stratified for the abdomen and the thorax were 1.9 +/- 1.7 and 1.6 +/- 1.8, respectively. Eighteen patients required thoracotomy, laparotomy, or both. The total blood requirement in the initial 24 hours postinjury was 4.0 +/- 4 Units. Deaths of four patients (11%) were a function of associated injuries and comorbid factors, not the result of uncontrolled pelvic hemorrhage. The data suggest that aggressive resuscitation of these patients and treatment of extrapelvic injuries in conjunction with early or delayed ORIF, without application of acute external fixation, resulted in a low overall mortality rate.

Changing etiology of iliopsoas abscess

Over a 5-year period, iliopsoas abscesses were found in 11 patients. Although the most common underlying condition was Crohns disease (3 of 11 patients), 5 abscesses resulted from hematogenous spread from a distant site. Each of these five patients was elderly, severely malnourished, or had an underlying chronic disease. Fever was a presenting sign in 8 of 11 patients, whereas all 4 patients who presented with back pain had nontuberculous lumbar osteomyelitis or disk space infections. No patient presented with the classic triad of fever, back pain, and anterior thigh or groin pain. Computed tomographic (CT) scans accurately established the clinical diagnosis in 10 of 11 patients. Two of the patients died. One patient was an intravenous drug abuser, whereas the other patient was being treated with steroids for systemic lupus erythematosus. Elderly patients, diabetics, and patients with chronic disease are susceptible to this kind of occult infection and may present with minimal clinical findings. Aggressive diagnosis using CT scanning and treatment with resection of involved bowel, complete drainage of the abscess, and prolonged antibiotics are required to salvage these patients.