Time is the enemy: Mortality in trauma patients with hemorrhage from torso injury occurs long before the "golden hour".

INTRODUCTION: The concept of the "Golden Hour" has been a time-honored tenet of prehospital trauma care, despite a paucity of data to substantiate its validity. Non-compressible torso hemorrhage has been demonstrated to be a significant cause of mortality in both military and civilian settings. We sought to characterize the impact of prehospital time and torso injury severity on survival. Furthermore, we hypothesized that time would be a significant determinant of mortality in patients with higher Abbreviated Injury Scale (AIS) grades of torso injury (AIS ≥ 4) and field hypotension (prehospital SBP ≤ 110 mmHg) as these injuries are commonly associated with hemorrhage. METHODS: Data for this analysis was generated from a registry of 2,523,394 injured patients entered into the National Trauma Data Bank Research Data Set from 2012 to 2014. Patients with torso injury were identified utilizing Abbreviated Injury Scale (AIS) for body regions 4 (Thorax) and 5 (Abdomen). Specific inclusion criteria for this study included pre-hospital time, prehospital SBP ≤110 mmHg, torso injury qualified by AIS and mortality. Patients with non-survivable torso injury (AIS = 6), severe head injuries (AIS ≥ 3), no signs of life in the field (SBP = 0), interfacility transfers, or those with any missing data elements were excluded. This classification methodology identified a composite cohort of 42,135 adult patients for analysis. RESULTS: The overall mortality rate of the study population was 7.9% (3326/42,135); Torso AIS and prehospital time were noted to be strong independent predictors of patient mortality in all population strata of the analysis (P < 0.05). The data demonstrated a profound incremental increase in mortality in the early time course after injury associated with torso AIS ≥4. CONCLUSION: In patients with high-grade torso injury, AIS grades ≥4, the degree anatomic disruption is associated with significant hemorrhage. In our study, a precipitous rise in patient mortality was exhibited in this high-grade injury group at prehospital times <30 min. Our data highlight the critical nature of prehospital time in patients with non-compressible torso hemorrhage. However, realizing that evacuation times ≤30 min may not be realistic, particularly in rural or austere environments, future efforts should be directed toward the development of therapies to increase the window of survival in the prehospital environment.

Complications of indwelling venous access devices in cancer patients.

PURPOSE: We undertook this study to review our experience with indwelling vascular access devices in cancer patients to identify factors associated with complications. PATIENTS AND METHODS: A total of 322 indwelling devices were placed in 274 cancer patients by a single surgeon. Devices were placed via percutaneous insertion in 72% (231 of 322) and via venous cutdown in 28% (91 of 322). We placed external catheters in 209 of 322 patients (65%) and subcutaneous infusion ports in 113 of 322 (35%). RESULTS: Pneumothorax occurred in four of 231 (1.7%) of the percutaneously placed devices. Postoperative complications included sepsis and thrombosis, which necessitated premature removal of the devices. Device related sepsis occurred in 28 of 209 patients (13%) with catheters and six of 113 patients (5%) with subcutaneous ports. Thrombosis occurred in 21 of 209 patients (10%) with catheters and seven of 113 (6%) with subcutaneous ports. In 15 of 19 devices removed for thrombosis, the tip was above the T3 level. Seventeen devices were placed in the saphenous vein, with a complication rate similar to that observed in upper-body devices. CONCLUSION: We found a significantly (P < .05, chi 2 analysis) increased incidence of thrombotic complications in patients with triple-lumen catheters (10 of 48) compared with double-lumen catheters (11 of 160), as well as a significantly (P < .05) decreased mean time until catheter failure (40 v 146 days). We also observed a significant increase in the rate of thrombosis in patients with a catheter tip above the T3 level. We therefore recommend the use of fluoroscopy at the time of placement to assure adequate catheter length and tip position and the use of triple-lumen catheters only when necessary for concurrent drug administration.

Ferric iron potentiates cell depolarization by a circulating shock protein.

OBJECTIVE: To determine whether or nor iron affects the depolarizing activity of a circulating shock protein that appears in plasma after hemorrhage. DESIGN: Randomized design. SETTING: University laboratory. ANIMALS: Healthy male Sprague-Dawley rats weighing 300 to 400 g with femoral artery and vein cannulas placed 4 days before hemorrhage. INTERVENTION: A 20-mL/kg hemorrhage and plasma collection. MAIN OUTCOME MEASURES: Depolarizing activity was measured as the increased fluorescence of an oxonol dye in the presence of Fe3+, Fe2+, or the iron chelator deferoxamine mesylate and was titrated against increasing concentrations of circulating shock protein or iron. Circulating shock protein was derived from plasma and was purified in two steps: stepwise ammonium sulfate precipitation followed by denaturing ion-exchange chromatography and refolding. RESULTS: At physiologic concentrations, Fe3+ but not Fe2+ potentiated the depolarizing activity of plasma after ammonium sulfate. Addition of deferoxamine abolished activity. Denaturing chromatography removed nearly all the depolarizing activity; however, Fe3+ restored activity to this fraction. Fe3+ increased total activity and decreased the concentration at which 50% activity was observed. CONCLUSION: These data indicate that physiologic concentrations of Fe3+ may act to modulate the depolarizing activity of circulating shock protein that in turn mediates the intracellular accumulation of salt and water in shock.

Pedestrian pelvic fractures: 5-year experience of a major urban trauma center.

BACKGROUND: Pedestrian injury accounts for approximately 14% of all vehicular-associated mortality. We performed a retrospective review of 1,014 injured pedestrians admitted to our statewide trauma center between January 1, 1990, and December 31, 1994, to determine the pattern and severity of pelvic injury in injured pedestrians, the types of associated injuries relative to those pelvic injury patterns, and the relationship between pelvic fracture treatment modalities and patient outcome. METHODS: Approximately 11% (111 of 1,014) of the patients had high-energy pelvic ring disruptions. The average age of these 57 men and 54 women was 39.4 years. The average admission Injury Severity Score and Glasgow Coma Scale values were 29.2 and 11.7, respectively. Pelvic injuries were classified according to the mechanism of injury: lateral compression, anteroposterior compression, vertical shear, and combined mechanical injury fractures. We compared the mean Glasgow Coma Scale scores, blood utilization, number of associated injuries, and mortality rate for each classification. RESULTS: Associated trauma included neurologic (30 of 111, 27.0%), thoracic (29 of 111, 26.1%), and abdominal injury (16 of 111, 14.4%). Overall blood product utilization averaged 1,971 mL within the first 24 hours and overall mortality was 26 of 111 (23.4%). There were 79 (71.2%) lateral compression, 23 (20.7%) anteroposterior compression, six (5.4%) vertical shear, and three (2.7%) combined mechanical injury fractures. As the severity of lateral compression and anteroposterior compression pelvic fractures increased, Glasgow Coma Scale scores decreased and Injury Severity Score values, blood utilization, number of associated injuries, and mortality rate increased. The highest mortality rate (50%) was associated with the most severe (grade III) lateral compression and anteroposterior compression injuries. Of particular interest, was the difference in the 24-hour blood utilization and mortality rates for patients with lateral compression type II pelvic fractures treated before (nonoperative management) and after (early external fixation) 1993: 4,760 versus 1,375 mL of blood and 36.4 versus 12.5% mortality rate, respectively. CONCLUSIONS: In conclusion, pelvic fracture appears to be a substantial factor in pedestrian morbidity and mortality. Although most pedestrian morbidity and mortality is not caused by the intrinsic nature of the pelvic fracture, the severity of these injuries is correlated with the degree of destructive energy imparted to the body as a whole, as manifested by the number and severity of associated injuries and the mortality rate.

Role of endotoxin in the response to experimentally induced bacteremia in chronically prepared rats.

Chronically prepared rats were injected intravenously with live Escherichia coli in doses from approximately 10(5) to approximately 10(9) colony-forming units (CFU). Significant dose-related increase in plasma adrenocorticotropin and corticosterone occurred after approximately 10(7) CFU. Fever occurred after approximately 10(7) CFU but not after approximately 10(9) CFU. These responses changed significantly but were not blocked completely when > 94% of the viable E. coli was removed from the inoculates. The remaining endotoxin activity in the inoculates resembled lipopolysaccharide (LPS) extracted from the same strain of E. coli on electrophoretic gels. Plasma endotoxin increased for > or = 240 min to 5.1 +/- 0.9 endotoxin units (EU)/ml after approximately 10(7) CFU and to 440 +/- 59 EU/ml after approximately 10(9) CFU. Endotoxin at approximately 10(9) CFU caused death within 24 h that was not predicted by the total activity of endotoxin that was injected. In contrast, extracted LPS with its strain and total activity matched to approximately 10(7) CFU mimicked the responses to this nonfatal dose. The total endotoxin activity of the injected bacteria appears to account for the effects of nonfatal doses of E. coli but not for the effects of fatal doses.

A circulating shock protein depolarizes cells in hemorrhage and sepsis.

OBJECTIVE: A study to determine if both septic and hemorrhagic shock lead to the appearance of a substance that depolarizes cells in plasma was performed. SUMMARY BACKGROUND DATA: Transmembrane potential decreases in skeletal muscle, hepatocytes, and red blood cells early in the development of both hemorrhagic and septic shock. The associated movement of ions and water into cells leads to extracellular fluid loss and exacerbates shock. METHODS: Adult male Sprague-Dawley rats with indwelling arterial and venous cannulae were bled 20 mL/kg or received intravenously 2 x 10(10) Escherichia coli suspended in 400 mL of 0.9% saline. Blood samples were taken after hemorrhage and induction of sepsis to determine the presence of a plasma factor that depolarized red blood cells. Control rats were not injected with E. coli or bled. Plasma from bled and septic rats was processed by sequential precipitation with ammonium sulfate and subjected to gel filtration. RESULTS: Depolarizing activity was highest 20 minutes after hemorrhage and 60 minutes after E. coli injection, decreasing to control levels by 2 (hemorrhage) and 4 (sepsis) hours. Control rats showed no significant change in depolarizing activity. Tryptic and chymotryptic digestion eliminated the depolarizing activity, indicating that the active substance is, at least in part, a protein. Depolarizing activity from bled and septic processed plasma was confined essentially to the 70% ammonium sulfate fraction and the activity migrated with an apparent molecular mass of 200 kD after gel filtration. Separation of the complex by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) produced an identical pattern of bands in both bled and septic animals. CONCLUSIONS: A circulating plasma protein complex of high molecular weight causes cellular depolarization in both hemorrhage and sepsis and may be responsible for the associated increases in cell sodium and water seen in both hemorrhagic and septic shock.

Pelvic ring disruptions: effective classification system and treatment protocols.

From January 1, 1985, to September 10, 1988, 210 consecutive patients with high-energy pelvic ring disruptions (exclusive of acetabular fractures) were admitted to a statewide referral center for adult multiple trauma. They were treated by one of four attending orthopaedic traumatologists per protocol as determined by their injury classification and hemodynamic status; the injury classification system was based on the vector of force involved and the quantification of disruption from that force, i.e., lateral compression, anteroposterior compression, vertical shear, and combined mechanical injury. Of the 210 patients, 162 had complete charts: 126 (78.0%) were admitted directly from the scene, 110 (67.9%) were injured in motor vehicle or motorcycle accidents, 25 (15.0%) were admitted in shock (blood pressure less than 90 mm Hg), the average Glasgow Coma Score was 13.2, and the average Injury Severity Score was 25.8. Treatment of the pelvic fracture included the following methods (alone or in combination): acute external fixation (45.0; 28.0%), open reduction/internal fixation (22; 13.5%), acute arterial embolization (11; 7.0%), and bedrest (68; 42.0%). Overall blood replacement averaged 5.9 units (lateral compression, 3.6 units; anteroposterior compression, 14.8 units; vertical shear, 9.2 units; combined mechanical, 8.5 units). Overall mortality was 8.6% (lateral compression, 7.0%; anteroposterior, 20.0%, vertical shear, 0%; combined mechanical, 18.0%). The cause of death was associated with the pelvic fracture in less than 50%; no patient with an isolated or vertical shear pelvic injury died. We conclude that the predictive value of our classification system (incorporating appreciation of the causative forces and resulting injury patterns) and our classification-based treatment protocols reduce the morbidity and mortality related to pelvic ring disruption.