Guidance Document for the Prehospital Use of Tranexamic Acid in Injured Patients.

Tranexamic acid (TXA) is being administered already in many prehospital air and ground systems. Insufficient evidence exists to support or refute the prehospital administration of TXA, and results are pending from several prehospital studies currently in progress. We have created this document to aid agencies and systems in best practices for TXA administration based on currently available best evidence. This document has been endorsed by the American College of Surgeons-Committee on Trauma, the American College of Emergency Physicians, and the National Association of EMS Physicians.

Goal directed brain tissue oxygen monitoring versus conventional management in traumatic brain injury: an analysis of in hospital recovery.

BACKGROUND: Brain tissue oxygen monitoring (pBtO2) has been advocated in the treatment of patients with severe traumatic brain injuries (TBI); however, controversy exists regarding the improvements that pBtO2 monitoring provides. The objective of our study was to evaluate our experience and effect on mortality with goal directed pBtO2 monitoring for severe TBI compared to traditional ICP/CPP monitoring. METHODS: All patients admitted with severe TBI (GCS < 8) to our Level 1 trauma center from June 2007 through June 2009 were retrospectively analyzed. All patients had ICP monitoring and pBtO2 monitors were placed based on the current practices of the attending neurosurgeon producing two temporally matched cohorts of patients with and without pBtO2 monitors. Exclusion criteria were age <18 years and survival <24 h. Goal-directed therapy was utilized in all patients to maintain ICP <20 mmHg and CPP >60 mmHg. Patients with pBtO2 monitors were managed to maintain a level >20 mmHg. RESULTS: 74 patients were treated for severe TBI over the 2-year study period with 37 patients in each group. Both groups were similar in age, sex, and admission Glascow Coma Score(GCS).The pBtO2-monitored group did, however, have significantly lower injury severity score [26 (25-30) vs. 30 (26-36), p = 0.03] and AIS Chest [0 (0-0) vs. 2 (0-3), p = 0.02]. There was no survival difference found (64.9 vs. 54.1 %, p = 0.34). No difference with respect to discharge GCS or discharge Functional Independence Measure score was identified. CONCLUSIONS: Compared with ICP/CPP-directed therapy alone, the addition of pBtO2 monitoring did not provide a survival or functional status improvement at discharge. The true clinical benefit of pBtO2 monitoring will require further study.

The national trauma triage protocol: how EMS perspective can inform the guideline revision.

OBJECTIVES: The Field Triage Guidelines (FTG) support emergency medical service (EMS) decisions regarding the most appropriate transport destination for injured patients. While the components of the algorithm are largely evidenced-based, the stepwise approach was developed with limited input from EMS providers. FTG are only useful if they can easily be applied by the field practitioner. We sought to gather end-user input on the current guidelines from a broad group of EMS stakeholders to inform the next revision of the FTG. METHODS: An expert panel composed an end-user feedback tool. Data collected included: demographics, EMS agency type, geographic area of respondents, use of the current FTG, perceived utility, and importance of each step in the algorithm (1: physiologic, 2: anatomic, 3 mechanistic, 4: special populations). The American College of Surgeons Committee on Trauma (ACS COT), in partnership with several key organizations, distributed the tool to reach as many providers as possible. RESULTS: 3958 responses were received (82% paramedics/emergency medical technicians, 9% physicians, 9% other). 94% responded directly to scene emergency calls and 4% were aeromedical providers. Steps 2 and 3 were used in 95% of local protocols, steps 1 and 4 in 90%. Step 3 was used equally in protocols across all demographics; however, step 1 was used significantly more in the air medical services than ground EMS (96% vs 88%, p<0.05). Geographic variation was demonstrated in FTG use based on the distance to a trauma center, but step 3 (not step 1) drove the majority of the decisions. This point was reinforced in the qualitative data with the comment, "I see the wreck before I see the patient." CONCLUSION: The FTG are widely used by EMS in the USA. The stepwise approach is useful; however, mechanism (not physiological criteria) drives most of the decisions and is evaluated first. Revision of the FTG should consider the experience of the end-users. LEVEL OF EVIDENCE: V.

Incidence of pulmonary fat embolism at autopsy: an undiagnosed epidemic.

BACKGROUND: To determine the incidence, time course, and severity of pulmonary fat embolism (PFE) and cerebral fat embolism (CFE) in trauma and nontrauma patients at the time of autopsy. METHODS: Prospectively, consecutive patients presenting for autopsy were evaluated for evidence pulmonary and brain fat embolism. The lung sections were obtained from the upper and lower lobe of the patients' lungs on the right and left and brain tissue. This tissue was prepared with osmium tetroxide for histologic evaluation. The number of fat droplets per high power field was counted for all sections. The autopsy reports and medical records were used to determine cause of death, time to death, injuries, if cardiopulmonary resuscitation (CPR) was attempted, sex, height, weight, and age. RESULTS: Fifty decedents were evaluated for PFE and CFE. The average age was 45.8 years ± 17.4 years, average body mass index was 30.1 kg/cm² ± 7.0 kg/cm², and 68% of the patients were men. The cause of death was determined to be trauma in 68% (34/50) of decedents, with 88% (30/34) blunt and 12% (4/34) penetrating. CPR was performed on 30% (15/50), and PFE was present in 76% (38/50) of all patients. Subjects with PFE had no difference with respect to sex, trauma, mechanism of injury, CPR, external contusions, fractures, head, spine, chest, abdominal, pelvic, and extremity injuries. However, subjects without PFE had significantly increased weight (109 ± 29 kg vs. 86 ± 18 kg; p = 0.023) but no difference in height or body mass index. PFE was present in 82% (28/34) of trauma patents and 63% (10/16) nontrauma patients. Eighty-eight percent of nontrauma patients and 86% of trauma patients who received CPR had PFE. Trauma patients with PFE showed no significant difference in any group. Eighty-eight percent of trauma patients died within 1 hour of injury, and 80% (24/30) of them had PFE at the time of autopsy. CFE was present only in one patient with a severe head and cervical spine injury. CONCLUSION: PFE is common in trauma patients. CPR is associated with a high incidence of PFE regardless of cause of death. PFE occurs acutely within the "golden hour" and should be considered in traumatically injured patients. Further studies are needed to evaluate the pathogenesis of PFE.

Cerebral perfusion pressure and intracranial pressure are not surrogates for brain tissue oxygenation in traumatic brain injury.

OBJECTIVE: Utilization of brain tissue oxygenation (pBtO(2)) is an important but controversial variable in the treatment of traumatic brain injury (TBI). We evaluated the correlation between pBtO(2)/CPP and pBtO(2)/ICP and determined the parameter most closely related to survival. METHODS: Consecutive, adult patients with severe TBI and pBtO(2) monitors were retrospectively identified. Time-indexed measurements of pBtO(2), CPP and ICP were collected and correlation coefficients were determined. Patients were then stratified according to survival and pBtO(2), CPP and ICP values were compared between groups. RESULTS: There were 4169 time-indexed data points (i.e., pBtO(2) with respective CPP and ICP values) in 15 patients. The cohort consisted of a mean age of 37±17 years, ISS of 27±7 and GCS of 4.5±1.5. Survival was 53% (8/15). In a normal regression models, neither the ICP (p=0.58) nor the CPP (p=0.71) predict pBtO(2) significantly. There was a significant difference in pBtO(2) in survivors (31.5±3.1 vs. 25.2±4.8, p=0.010) but not in CPP or ICP. Survivors had a lower proportion of time with pBtO(2)<25 mmHg [20% (3.4-44.6) vs. 40% (16.2-89), p=0.049]. In contrast, survivors had a greater proportion of time with CPP<70 and no difference in the proportion of time with and ICP>20. CONCLUSIONS: CPP and ICP should not be used as surrogates for pBtO(2) since cerebral oxygenation varies independently of cerebral hemodynamics and pressures. Brain tissue oxygen monitoring in patients with TBI provides unique information regarding cerebral oxygenation the utility of which remains to be fully described. SIGNIFICANCE: CPP and ICP are not surrogates for pBtO(2). Brain tissue oxygenation monitoring provides unique information for the treatment of traumatically injured patients.

The first 72 hours of brain tissue oxygenation predicts patient survival with traumatic brain injury.

BACKGROUND: Utilization of brain tissue oxygenation (pBtO(2)) is an important but controversial variable in the treatment of traumatic brain injury. We hypothesize that pBtO(2) values over the first 72 hours of monitoring are predictive of mortality. METHODS: Consecutive, adult patients with severe traumatic brain injury and pBtO(2) monitors were retrospectively identified. Time-indexed measurements of pBtO(2), cerebral perfusion pressure (CPP), and intracranial pressure (ICP) were collected, and average values over 4-hour blocks were determined. Patients were stratified according to survival, and repeated measures analysis of variance was used to compare pBtO(2), CPP, and ICP. The pBtO(2) threshold most predictive for survival was determined. RESULTS: There were 8,759 time-indexed data points in 32 patients. The mean age was 39 years ± 16.5 years, injury severity score was 27.7 ± 10.7, and Glasgow Coma Scale score was 6.6 ± 3.4. Survival was 68%. Survivors consistently demonstrated higher pBtO(2) values compared with nonsurvivors including age as a covariate (F = 12.898, p < 0.001). Individual pBtO(2) was higher at the time points 8 hours, 12 hours, 20 hours to 44 hours, 52 hours to 60 hours, and 72 hours of monitoring (p < 0.05). There was no difference in ICP (F = 1.690, p = 0.204) and CPP (F = 0.764, p = 0.389) values between survivors and nonsurvivors including age as a covariate. Classification and regression tree analysis identified 29 mm Hg as the threshold at which pBtO(2) was most predictive for mortality. CONCLUSION: The first 72 hours of pBtO(2) neurologic monitoring predicts mortality. When the pBtO(2) monitor remains below 29 mm Hg in the first 72 hours of monitoring, mortality is increased. This study challenges the brain oxygenation threshold of 20 mm Hg that has been used conventionally and delineates a time for monitoring pBtO(2) that is predictive of outcome. LEVEL OF EVIDENCE: III, prognostic study.

Tight blood glucose control in trauma patients: Who really benefits?

BACKGROUND: This study was designed to evaluate the effect of intensive insulin control (IIT) on outcomes for traumatically injured patients as a function of injury severity score (ISS) and age. PATIENTS AND METHODS: A retrospective review of 2028 adult trauma patients admitted to the surgical intensive care unit (SICU) in a Level I trauma center was performed. Data were collected from a 48-month period before (Pre-IIT) (goal blood glucose 80-200 mg/dL) and after (Post-IIT) (goal blood glucose level 80-110 mg/dL), an IIT protocol was initiated. Patients were stratified by age and ISS. The primary endpoint was mortality. RESULTS: There were 784 Pre-IIT and 1244 Post-IIT patients admitted. There was no significant difference between Pre-IIT vs. Post-IIT for the mechanism of injury or ISS. Values for the Pre-IIT group were significantly higher for mortality (21.5% vs. 14.7%, P<0.001) and hospital, but not ICU length of stay were decreased. A significant improvement in mortality was demonstrated between Pre-IIT vs. Post-IIT stratified within the age groups of 41-50, 51-60, and 61 but not the groups 18-30 and 31-40. Mean glucose levels (mg/dL) decreased significantly after the institution of IIT (144.7±1.4 vs. 130.9±0.9; P<0.001). In addition, the occurrence per patient of blood glucose levels <40 mg/dL increased (0.77% vs. 2.86%; P=0.001) and blood glucose levels greater than 200 mg/dL was similar (39.1% vs. 38.8%; P=0.892) in the Pre-IIT and Post-IIT groups, respectively. Glycemic variability, reflected by the standard deviation of each patient's mean glucose level during ICU stay, as well as mean glucose level were lower in survivors than in nonsurvivors. Finally, multivariable logistic regression analysis identified both mean glucose level and glycemic variability as independent contributors to the risk of mortality. CONCLUSIONS: The implementation of IIT has been associated with a decrease in both hospital length of stay as well as mortality. Average glucose value and glucose variability are independent predictors of survival. Trauma patients with moderate, severe, and very severe injuries benefit most from IIT. These observational data suggest that patients over 40 years of age benefited a great deal more than their younger counterparts from IIT. This study supports the need for a randomized controlled trial to investigate the role of IIT in traumatically injured patients.

Radiation exposure in trauma patients.

BACKGROUND: Trauma patients are exposed to a large amount of ionizing radiation. Radiologic examinations may include a multitude of plain films, computed tomography scans, and/or fluoroscopic examination. Previous studies have assessed radiation exposure to staff members at trauma centers, and in pregnant trauma patients. The purpose of the current study is to evaluate the amount of radiation to which trauma patients are exposed in a Level I trauma center. METHODS: The study used a prospective cohort design. All patients for whom a trauma code was activated between the months of September 2004 and July of 2005 were eligible to be enrolled in the study. Upon arrival to the trauma bay, a dosimeter badge, that measures ionizing radiation, was attached to a Velcro bracelet on the wrist of the patient. The badges were removed at the time of discharge from the hospital and analyzed. RESULTS: Data were collected on 224 patients (167 adults, 57 pediatric). The median amount of radiation exposure to all patients equaled 68 MREM (Interquartile range 31-181). A significant increase in the median amount of radiation exposure was found in patients with orthopedic injuries (107 MREM vs. 45 MREM), an Injury Severity Score (ISS) >15 (107 MREM vs. 46 MREM), a length of stay >than 1 week (105 MREM vs. 65 MREM), age >18 (82 MREM vs. 44 MREM), and when >11 radiologic procedures were performed (127 MREM vs. 46 MREM). CONCLUSION: Trauma patients are being exposed to high amounts of radiation. Patients with orthopedic injuries, and those more severely injured, are at an increased risk. Further precautions to limit radiation exposure in this population are needed.