Early Glasgow Coma Scale Score and Prediction of Traumatic Brain Injury: A Secondary Analysis of Three Harmonized Prehospital Randomized Clinical Trials.

OBJECTIVES: The prehospital prediction of the radiographic diagnosis of traumatic brain injury (TBI) in hemorrhagic shock patients has the potential to promote early therapeutic interventions. However, the identification of TBI is often challenging and prehospital tools remain limited. While the Glasgow Coma Scale (GCS) score is frequently used to assess the extent of impaired consciousness after injury, the utility of the GCS scores in the early prehospital phase of care to predict TBI in patients with severe injury and concomitant shock is poorly understood. METHODS: We performed a post-hoc, secondary analysis utilizing data derived from three randomized prehospital clinical trials: the Prehospital Air Medical Plasma trial (PAMPER), the Study of Tranexamic Acid During Air Medical and Ground Prehospital Transport trial (STAAMP), and the Pragmatic Prehospital Type O Whole Blood Early Resuscitation (PPOWER) trial. Patients were dichotomized into two cohorts based on the presence of TBI and then further stratified into three groups based on prehospital GCS score: GCS 3, GCS 4-12, and GCS 13-15. The association between prehospital GCS score and clinical documentation of TBI was assessed. RESULTS: A total of 1,490 enrolled patients were included in this analysis. The percentage of patients with documented TBI in those with a GCS 3 was 59.5, 42.4% in those with a GCS 4-12, and 11.8% in those with a GCS 13-15. The positive predictive value (PPV) of the prehospital GCS score for the diagnosis of TBI is low, with a GCS of 3 having only a 60% PPV. Hypotension and prehospital intubation are independent predictors of a low prehospital GCS. Decreasing prehospital GCS is strongly associated with higher incidence or mortality over time, irrespective of the diagnosis of TBI. CONCLUSIONS: The ability to accurately predict the presence of TBI in the prehospital phase of care is essential. The utility of the GCS scores in the early prehospital phase of care to predict TBI in patients with severe injury and concomitant shock is limited. The use of novel scoring systems and improved technology are needed to promote the accurate early diagnosis of TBI.

Risk factors for massive transfusion in obstetrical hemorrhage and consideration of a whole blood program.

BACKGROUND: Postpartum hemorrhage (PPH) is one of the leading causes of obstetric complications. The goal of this study was to identify risk factors for obstetric (OB) massive transfusion (MT) and determine the feasibility of developing a low-titer group O RhD-positive whole blood (LTO + WB) protocol for OB hemorrhage. STUDY DESIGN AND METHODS: A retrospective study of OB patients who received transfusion within 24 h. MT patients were those who received >3 U of pRBC within 1 h or > 10 U in 24 h. Patient demographics, OB history, comorbidities, blood type, antibody status, and known risk factors for PPH and maternal-fetal outcomes were compared. Logistic regression was used for univariate and multivariate analyses. RESULTS: Of the 610 transfused OB patients, 12.0% (n = 73) required MT. Groups were well matched for body mass index (BMI), maternal comorbidities, and history of spontaneous vaginal deliveries. The incidence of the previous cesarean section was higher in the MT group. Exactly 93.9% of patients were RhD-positive and 3.77% of all patients possessed an antibody on pretransfusion testing. Patients with MT had a longer length of stay (LOS), higher rate of intensive care unit (ICU) admission, fetal death, and hysterectomy. Multivariate analysis found age >35, PPH, placenta percreta, accreta, and increta to be significant (p < .05) risk factors for MT. DISCUSSION: Patients over 35 years and those with abnormal placentation are at increased risk of requiring MT. With a time to delivery of 2 days, potential MT patients can be identified early, and with a 94% rate of RhD-positive+, they are eligible to receive low-titer O whole blood (LTOWB) providing hemostatic resuscitation with reduced donor exposure.

Activation and On-Scene Intervals for Severe Trauma EMS Interventions: An Analysis of the NEMSIS Database.

Objective: Time to care is a determinant of trauma patient outcomes, and timely delivery of trauma care to severely injured patients is critical in reducing mortality. Numerous studies have analyzed access to care using prehospital intervals from a Carr et al. meta-analysis of studies from 1975 to 2005. Carr et al.'s research sought to determine national mean activation and on-scene intervals for trauma patients using contemporary emergency medical services (EMS) records. Since the Carr et al. meta-analysis was published, the National Highway Traffic Safety Administration (NHTSA) created and refined the National Emergency Medical Services Information System (NEMSIS) database. We sought to perform a modern analysis of prehospital intervals to establish current standards and temporal patterns.Methods: We utilized NEMSIS to analyze EMS data of trauma patients from 2016 to 2019. The dataset comprises more than 94 million EMS records, which we filtered to select for severe trauma and stratified by type of transport and rurality to calculate mean activation and on-scene intervals. Furthermore, we explored the impact of basic life support (BLS) and advanced life support (ALS) of ground units on activation and on-scene time intervals.Results: Mean activation and on-scene intervals for ground transport were statistically different when stratified by rurality. Urban, suburban, and rural ground activation intervals were 2.60 ± 3.94, 2.88 ± 3.89, and 3.33 ± 4.58 minutes, respectively. On-scene intervals were 15.50 ± 10.46, 17.56 ± 11.27, and 18.07 ± 16.13 minutes, respectively. Mean helicopter transport activation time was 13.75 ± 7.44 minutes and on-scene time was 19.42 ± 16.09 minutes. This analysis provides an empirically defined mean for activation and on-scene times for trauma patients based on transport type and rurality. Results from this analysis proved to be significantly longer than the previous analysis, except for helicopter transport on-scene time. Shorter mean intervals were seen in ALS compared to BLS for activation intervals, however ALS on-scene intervals were marginally longer than BLS.Conclusions: With the increasing sophistication of geospatial technologies employed to analyze access to care, these intervals are the most accurate and up-to-date and should be included in access to care models.

Compensatory reserve and pulse character: Enhanced potential to predict urgency for transfusion and other life-saving interventions after traumatic injury.

BACKGROUND: Field triage of trauma patients requires timely assessment of physiologic status to determine resuscitative needs. Vital signs and rudimentary assessments such as pulse character (PC) are used by first responders to guide decision making. The compensatory reserve measurement (CRM) has demonstrated utility as an easily interpretable method for assessing patient status. We hypothesized that the ability to identify injured patients requiring transfusion and other life-saving interventions (LSI) using a measurement of pulse character could be enhanced by the addition of the CRM. METHODS: We performed a prospective observational study on 300 trauma patients admitted to a level I trauma center. CRM was recorded continuously after device placement on arrival. Patient demographics, field and trauma resuscitation unit vital signs, therapeutic interventions, and outcomes were collected. A field SBP <100 mmHg was utilized as a surrogate for abnormal PC as previously validated. A patient with a CRM threshold value of <60% was considered clinically compromised with a risk of onset of decompensated shock. Data were analyzed to assess the capacity of CRM and pulse character separately or in combination to predict LSI defined as need for transfusion, intubation, tube thoracostomy, or operative/ angiographic hemorrhage control. RESULTS: An improvement in the predictive capability for LSI, transfusion, or a composite outcome was demonstrated by the combination of CRM and PC compared to either measure alone. CONCLUSIONS: Combining PC assessment with CRM has the potential to enhance the recognition of injured patients requiring life-saving intervention thus improving sensitivity of decision support for prehospital providers.

The regional whole blood program in San Antonio, TX: A 3-year update on prehospital and in-hospital transfusion practices for traumatic and non-traumatic hemorrhage.

Low titer type O Rh-D + whole blood (LTO + WB) has become a first-line resuscitation medium for hemorrhagic shock in many centers around the World. Showing early effectiveness on the battlefield, LTO + WB is used in both the pre-hospital and in-hospital settings for traumatic and non-traumatic hemorrhage resuscitation. Starting in 2018, the San Antonio Whole Blood Collaborative has worked to provide LTO + WB across Southwest Texas, initially in the form of remote damage control resuscitation followed by in-hospital trauma resuscitation. This program has since expanded to include pediatric trauma resuscitation, obstetric hemorrhage, females of childbearing potential, and non-traumatic hemorrhage. The objective of this manuscript is to provide a three-year update on the successes and expansion of this system and outline resuscitation challenges in special populations.

Early Prehospital Tranexamic Acid Following Injury Is Associated With a 30-day Survival Benefit: A Secondary Analysis of a Randomized Clinical Trial.

OBJECTIVE: We sought to characterize the timing of administration of prehospital tranexamic acid (TXA) and associated outcome benefits. BACKGROUND: TXA has been shown to be safe in the prehospital setting post-injury. METHODS: We performed a secondary analysis of a recent prehospital randomized TXA clinical trial in injured patients. Those who received prehospital TXA within 1 hour (EARLY) from time of injury were compared to those who received prehospital TXA beyond 1 hour (DELAYED). We included patients with a shock index of >0.9. Primary outcome was 30-day mortality. Kaplan-Meier and Cox Hazard regression were utilized to characterize mortality relationships. RESULTS: EARLY and DELAYED patients had similar demographics, injury characteristics, and shock severity but DELAYED patients had greater prehospital resuscitation requirements and longer prehospital times. Stratified Kaplan-Meier analysis demonstrated significant separation for EARLY patients (N = 238, log-rank chi-square test, 4.99; P = 0.03) with no separation for DELAYED patients (N = 238, log-rank chi-square test, 0.04; P = 0.83). Stratified Cox Hazard regression verified, after controlling for confounders, that EARLY TXA was associated with a 65% lower independent hazard for 30-day mortality [hazard ratio (HR) 0.35, 95% confidence interval (CI) 0.19-0.65, P = 0.001] with no independent survival benefit found in DELAYED patients (HR 1.00, 95% CI 0.63-1.60, P = 0.999). EARLY TXA patients had lower incidence of multiple organ failure and 6-hour and 24-hour transfusion requirements compared to placebo. CONCLUSIONS: Administration of prehospital TXA within 1 hour from injury in patients at risk of hemorrhage is associated with 30-day survival benefit, lower incidence of multiple organ failure, and lower transfusion requirements.

Timing of repair of blunt thoracic aortic injuries in the thoracic endovascular aortic repair era.

OBJECTIVE: Thoracic endovascular aortic repair (TEVAR) is the preferred operative treatment of blunt thoracic aortic injuries (BTAIs). Its use is associated with improved outcomes compared with open surgical repair and nonoperative management. However, the optimal time from injury to repair is unknown and remains a subject of debate across different societal practice guidelines. The purpose of this study was to evaluate national trends in the management of BTAI, with a specific focus on the impact of timing of repair on outcomes. METHODS: Using the National Trauma Data Bank, we identified adult patients with BTAI between 2012 and 2017. Patients with prehospital or emergency department cardiac arrest or incomplete data sets were excluded from analysis. Patients were classified according to timing of repair: group 1, <24 hours; and group 2, ≥24 hours. The primary outcome evaluated was in-hospital mortality; secondary outcomes included overall hospital and intensive care unit length of stay. Multivariable logistic regression was performed to identify independent predictors of mortality. RESULTS: The analysis was completed for 2821 patients who underwent TEVAR for BTAI with known operative times. The overall mortality in the patient cohort was 8.4% (238/2821); 75% of patients undergoing TEVAR were repaired within 24 hours. Mortality was more than twofold greater in group 1 compared with group 2 (9.8% [207/2118] vs 4.4% [31/703]; P = .001). This mortality benefit persisted across injury severity groups and was independent of the presence of serious extrathoracic injuries. Logistic regression analysis, adjusting for age ≥65 years, Glasgow Coma Scale score ≤8, systolic blood pressure ≤90 mm Hg at admission, and serious extrathoracic injuries, showed a higher adjusted mortality in group 1 (odds ratio, 2.54; 95% confidence interval, 1.66-3.91; P = .001). CONCLUSIONS: The majority of patients with BTAI undergo endovascular repair within 24 hours of injury. Patients undergoing delayed repair have improved survival compared with those repaired within the first 24 hours of injury in spite of similar injury patterns and severity. In patients with BTAIs without signs of imminent rupture, delaying endovascular repair beyond 24 hours after injury should be considered.

Compensatory reserve detects subclinical shock with more expeditious prediction for need of life-saving interventions compared to systolic blood pressure and blood lactate.

INTRODUCTION: We conducted a prospective observational study on 205 trauma patients at a level I trauma facility to test the hypothesis that a compensatory reserve measurement (CRM) would identify higher risk for progression to shock and/or need a life-saving interventions (LSIs) earlier than systolic blood pressure (SBP) and blood lactate (LAC). METHODS: A composite outcome metric included blood transfusion, procedural LSI, and mortality. Discrete measures assessed as abnormal (ab) were SBP <90 mmHg, CRM <60%, and LAC >2.0. A graded categorization of shock was defined as: no shock (normal [n] SBP [n-SBP], n-CRM, n-LAC); sub-clinical shock (ab-CRM, n-SBP, n-LAC); occult shock (n-SBP, ab-CRM, ab-LAC); or overt shock (ab-SBP, ab-CRM, ab-LAC). RESULTS: Three patients displayed overt shock, 53 displayed sub-clinical shock, and 149 displayed no shock. After incorporating lactate into the analysis, 86 patients demonstrated no shock, 25 were classified as sub-clinical shock, 91 were classified as occult shock, and 3 were characterized as overt shock. Each shock subcategory revealed a graded increase requiring LSI and transfusion. Initial CRM was associated with progression to shock (odds ratio = 0.97; p < .001) at an earlier time than SBP or LAC. CONCLUSIONS: Initial CRM uncovers a clinically relevant subset of patients who are not detected by SBP and LAC. Our results suggest CRM could be used to more expeditiously identify injured patients likely to deteriorate to shock, with requirements for blood transfusion or procedural LSI.

Prehospital whole blood reduces early mortality in patients with hemorrhagic shock.

BACKGROUND: Low titer O+ whole blood (LTOWB) is being increasingly used for resuscitation of hemorrhagic shock in military and civilian settings. The objective of this study was to identify the impact of prehospital LTOWB on survival for patients in shock receiving prehospital LTOWB transfusion. STUDY DESIGN AND METHODS: A single institutional trauma registry was queried for patients undergoing prehospital transfusion between 2015 and 2019. Patients were stratified based on prehospital LTOWB transfusion (PHT) or no prehospital transfusion (NT). Outcomes measured included emergency department (ED), 6-h and hospital mortality, change in shock index (SI), and incidence of massive transfusion. Statistical analyses were performed. RESULTS: A total of 538 patients met inclusion criteria. Patients undergoing PHT had worse shock physiology (median SI 1.25 vs. 0.95, p < .001) with greater reversal of shock upon arrival (-0.28 vs. -0.002, p < .001). In a propensity-matched group of 214 patients with prehospital shock, 58 patients underwent PHT and 156 did not. Demographics were similar between the groups. Mean improvement in SI between scene and ED was greatest for patients in the PHT group with a lower trauma bay mortality (0% vs. 7%, p = .04). No survival benefit for patients in prehospital cardiac arrest receiving LTOWB was found (p > .05). DISCUSSION: This study demonstrated that trauma patients who received prehospital LTOWB transfusion had a greater improvement in SI and a reduction in early mortality. Patient with prehospital cardiac arrest did not have an improvement in survival. These findings support LTOWB use in the prehospital setting. Further multi-institutional prospective studies are needed.

From battlefront to homefront: creation of a civilian walking blood bank.

Hemorrhagic shock remains the leading cause of preventable death on the battlefield, despite major advances in trauma care. Early initiation of balanced resuscitation has been shown to decrease mortality in the hemorrhaging patient. To address transfusion limitations in austere environments or in the event of multiple casualties, walking blood banks have been used in the combat setting with great success. Leveraging the success of the region-wide whole blood program in San Antonio, Texas, we report a novel plan that represents a model response to mass casualty incidents.

Rectal Injury After Foreign Body Insertion: Secondary Analysis From the AAST Contemporary Management of Rectal Injuries Study Group.

BACKGROUND: Retained rectal foreign bodies are a common but incompletely studied problem. This study defined the epidemiology, injury severity, and outcomes after rectal injuries following foreign body insertion. METHODS: Twenty-two level I trauma centers retrospectively identified all patients sustaining a rectal injury in this AAST multi-institutional trial (2005-2014). Only patients injured by foreign body insertion were included in this secondary analysis. Exclusion criteria were death before rectal injury management or ≤48 h of admission. Demographics, clinical data, and outcomes were collected. Study groups were defined as partial thickness (AAST grade I) versus full thickness (AAST grades II-V) injuries. Subgroup analysis was performed by management strategy (nonoperative versus operative). RESULTS: After exclusions, 33 patients were identified. Mean age was 41 y (range 18-57), and 85% (n = 28) were male. Eleven (33%) had full thickness injuries and 22 (67%) had partial thickness injuries, of which 14 (64%) were managed nonoperatively and 8 (36%) operatively (proximal diversion alone [n = 3, 14%]; direct repair with proximal diversion [n = 2, 9%]; laparotomy without rectal intervention [n = 2, 9%]; and direct repair alone [n = 1, 5%]). Subgroup analysis of outcomes after partial thickness injury demonstrated significantly shorter hospital length of stay (2 ± 1; 2 [1-5] versus 5 ± 2; 4 [2-8] d, P = 0.0001) after nonoperative versus operative management. CONCLUSIONS: Although partial thickness rectal injuries do not require intervention, difficulty excluding full thickness injuries led some surgeons in this series to manage partial thickness injuries operatively. This was associated with significantly longer hospital length of stay. Therefore, we recommend nonoperative management after a retained rectal foreign body unless full thickness injury is conclusively identified.

Impact of time to repair on outcomes in patients with lower extremity arterial injuries.

BACKGROUND: Six hours has long been considered the threshold of ischemia after peripheral artery injury. However, there is a paucity of evidence regarding the impact of operative delays on morbidity and mortality in patients with lower extremity arterial injuries. METHODS: We analyzed the records of 3,441,259 injured patients entered into the National Trauma Data Bank Research Dataset from 2012 to 2015. Patients (≥16 years) with lower extremity arterial injuries were identified by International Classification of Diseases, Ninth Revision injury and procedure codes. Patients with crush injuries, patients with prehospital or emergency department cardiac arrest, those not transferred directly from point of injury, and patients in whom a nonoperative management strategy was attempted were excluded from analysis. RESULTS: We examined the data from 4406 patients with lower extremity arterial injuries; 85% of the patients were male, with a mean age of 35 years. The overall mortality in this cohort was 3.2% (143/4406); the amputation rate was 11.3% (499/4406). Using a multivariate logistic regression model, blunt mechanisms of injury, increased time from injury to operating room arrival, nerve injury, associated lower extremity fractures, increased age, and Injury Severity Score were associated with increased amputation risk. The amputation rate in those undergoing repair within 60 minutes was 6% compared with 11.7% and 13.4% in those undergoing repair after 1 to 3 hours and 3 to 6 hours, respectively. CONCLUSIONS: Optimal limb salvage is achieved when revascularization of lower extremity arterial injury occurs within 1 hour of injury. To improve survival and recovery after extremity arterial injury, efforts should be focused on strategies to expedite reperfusion of the injured limb.

Outcomes of traumatic hemorrhagic shock and the epidemiology of preventable death from injury.

The majority of potentially preventable deaths after trauma are related to hemorrhage and occur early after injury, with the largest number of deaths occurring before hospital arrival. Approximately one-fourth of trauma deaths may be potentially preventable through early medical and surgical interventions. Interventions dedicated to bleeding control and hemostatic resuscitation have demonstrated merit in decreasing hemorrhagic injury mortality. Advancing these novel strategies to the casualty in the prehospital phase of care, particularly in tactical or austere environments, may prove beneficial for hemorrhage mitigation to temporize the window of survival to definitive care. Future studies of resuscitation and survival after traumatic injury must include analysis of prehospital deaths to fully understand the outcomes of early interventions.

Give the trauma patient what they bleed, when and where they need it: establishing a comprehensive regional system of resuscitation based on patient need utilizing cold-stored, low-titer O+ whole blood.

BACKGROUND: Despite countless advancements in trauma care a survivability gap still exists in the prehospital setting. Military studies clearly identify hemorrhage as the leading cause of potentially survivable prehospital death. Shifting resuscitation from the hospital to the point of injury has shown great promise in decreasing mortality among the severely injured. MATERIALS AND METHODS: Our regional trauma network (Southwest Texas Regional Advisory Council) developed and implemented a multiphased approach toward facilitating remote damage control resuscitation. This approach required placing low-titer O+ whole blood (LTO+ WB) at helicopter emergency medical service bases, transitioning hospital-based trauma resuscitation from component therapy to the use of whole blood, modifying select ground-based units to carry and administer whole blood at the scene of an accident, and altering the practices of our blood bank to support our new initiative. In addition, we had to provide information and training to an entire large urban emergency medical system regarding changes in policy. RESULTS: Through a thorough, structured program we were able to successfully implement point-of-injury resuscitation with LTO+ WB. Preliminary evaluation of our first 25 patients has shown a marked decrease in mortality compared to our historic rate using component therapy or crystalloid solutions. Additionally, we have had zero transfusion reactions or seroconversions. CONCLUSION: Transfusion at the scene within minutes of injury has the potential to save lives. As our utilization expands to our outlying network we expect to see a continued decrease in mortality among significantly injured trauma patients.

Left atrial thrombi following tranexamic acid in a bleeding trauma patient-A word of caution.

We describe the case of a bleeding trauma patient who received tranexamic acid (TXA) during air transport who subsequently developed multiple intra-cardiac thrombi. The administration of TXA during transport may be associated with this unusual presentation.

Remote Damage Control Resuscitation in Austere Environments.

Hemorrhage is the leading cause of preventable military and civilian trauma death. Damage control resuscitation with concomitant mechanical hemorrhage control has become the preferred in-hospital treatment of hemorrhagic shock. In particular, plasma-based resuscitation with decreased volumes of crystalloids and artificial colloids as part of damage control resuscitation has improved outcomes in the military and civilian sectors. However, translation of these principles and techniques to the prehospital, remote, and austere environments, known as remote damage control resuscitation, is challenging given the resource limitations in these settings. Rapid administration of tranexamic acid and reconstituted freeze-dried (lyophilized) plasma as early as the point of injury are feasible and likely beneficial, but comparative studies in the literature are lacking. Whole blood is likely the best fluid therapy for traumatic hemorrhagic shock, but logistical hurdles need to be addressed. Rapid control of external hemorrhage with hemostatic dressings and extremity tourniquets are proven therapies, but control of noncompressible hemorrhage (ie, torso hemorrhage) remains a significant challenge.

Implications of humanitarian orthopaedic surgery in a combat zone: Operation Enduring Freedom and Iraqi Freedom experience.

The primary mission of deployed military orthopaedic surgeons in a combat zone is to treat musculoskeletal battlefield trauma and associated wartime injuries. The role of humanitarian surgical care during combat operations has not been defined. An anonymous online survey was sent to databases containing all U.S. military active-duty orthopaedic surgeons as well as to members of the Society of Military Orthopaedic Surgeons. Inclusion criteria for the study were defined as at least one deployment to Iraq (Operation Iraqi Freedom, OIF) or Afghanistan (Operation Enduring Freedom, OEF). Three hundred fifty-six invitations were sent with 107 orthopaedic surgeons completing the survey. Respondents reported approximately 3,000 humanitarian surgeries performed in the combat zone, with 70% to 80% involving chronic deformity and nonunion surgeries. Seventy-nine percent of the respondents believed that humanitarian surgery was a key component of the mission, improved skills (73%), benefited population (76%), and improved security (61%). A significant amount of humanitarian surgery in the combat zone has been performed in OEF/OIF.

Immediate Angiography and Decreased In-Hospital Mortality of Adult Trauma Patients: A Nationwide Study.

PURPOSE: This study aimed to elucidate whether immediate angiography within 30 min is associated with lower in-hospital mortality compared with non-immediate angiography. MATERIALS AND METHODS: We conducted a retrospective cohort study using a nationwide trauma databank (2019-2020). Adult trauma patients who underwent emergency angiography within 12 h after hospital arrival were included. Patients who underwent surgery before angiography were excluded. Immediate angiography was defined as one performed within 30 min after arrival (door-to-angio time ≤ 30 min). In-hospital mortality and non-operative management (NOM) failure were compared between patients with immediate and non-immediate angiography. Inverse probability weighting with propensity scores was conducted to adjust patient demographics, injury mechanism and severity, vital signs on hospital arrival, and resuscitative procedures. A restricted cubic spline curve was drawn to reveal survival benefits by door-to-angio time. RESULTS: Among 1,455 patients eligible for this study, 92 underwent immediate angiography. Angiography ≤ 30 min was associated with decreased in-hospital mortality (5.0% vs 11.1%; adjusted odds ratio [OR], 0.42 [95% CI, 0.31-0.56]; p < 0.001), as well as lower frequency of NOM failure: thoracotomy and laparotomy after angiography (0.8% vs. 1.8%; OR, 0.44 [0.22-0.89] and 2.6% vs. 6.5%; OR, 0.38 [0.26-0.56], respectively). The spline curve showed a linear association between increasing mortality and prolonged door-to-angio time in the initial 100 min after arrival. CONCLUSION: In trauma patients, immediate angiography ≤ 30 min was associated with lower in-hospital mortality and fewer NOM failures. LEVEL OF EVIDENCE: Level 3b, non randomized controlled cohort/follow up study.

EVIDENCE FOR BENEFICIAL USE OF THE COMPENSATORY RESERVE MEASUREMENT IN GUIDING INTRAOPERATIVE RESUSCITATION: A PROSPECTIVE COHORT STUDY OF ORTHOTOPIC LIVER TRANSPLANT RECIPIENTS.

ABSTRACT: Introduction: The compensatory reserve measurement (CRM) is a continuous noninvasive monitoring technology that provides an assessment of the integrated capacity of all physiological mechanisms associated with responses to a hypovolemic stressor such as hemorrhagic shock. No prior studies have analyzed its use for intraoperative resuscitation guidance. Methods: A prospective observational study was conducted of 23 patients undergoing orthotopic liver transplant. Chart review was performed to identify timing of various intraoperative events. Data were compared based on predefined thresholds for existence of hemorrhagic shock: CRM lower than 40%, systolic blood pressure (SBP) lower than 90 mm Hg (SBP90), and heart rate (HR) higher than 100 beats per minute (HR100). Regression analysis was performed for predicting resuscitation events, and nonlinear eXtreme Gradient Boosting (XGBoost) models were used to compare CRM with standard vital sign measures. Results: Events where CRM dropped lower than 40% were 2.25 times more likely to lead to an intervention, whereas HR100 and SBP90 were not associated with intraoperative interventions. XGBoost prediction models showed superior discriminatory capacity of CRM alone compared with the model with SBP and HR and no difference when all three were combined (CRM-HR-SBP). All XGBoost models outperformed equivalent linear regression models. Conclusion: These results demonstrate that CRM can provide an adjunctive clinical tool that can augment early and accurate of hemodynamic compromise and promote goal-directed resuscitation in the perioperative setting.

Retrospective analysis of the effects of hypocalcemia in severely injured trauma patients.

BACKGROUND: It has been suggested that the Lethal Triad be modified to include hypocalcemia, coined as the Lethal Diamond. Hypocalcemia in trauma has been attributed to multiple mechanisms, but new evidence suggests that traumatic injury may result in the development of hypoCa independent of blood transfusion. We hypothesize that hypocalcemia is associated with increased blood product requirements and mortality. METHODS: A retrospective study of 1,981 severely injured adult trauma patients from 2016 to 2019. Ionized calcium (iCa) levels were obtained on arrival and subjects were categorized by a threshold iCa level of 1.00 mmol/L and compared. Univariable and multivariable logistic regression analysis was performed. RESULTS: The hypocalcemia (iCa <1.00 mmol/L) group had increased rate of overall (p = 0.001), 4-hr (p = 0.007), and 24-hr (p = 0.003) mortality. There was no difference in prehospital transfusion volume between groups (p = 0.25). Hypocalcemia was associated with increased blood product requirements at 4 h (p <0.001), 24 h (p <0.001), and overall hospital length of stay (p <0.001). Logistic regression analysis showed increased odds of 4-hour mortality (OR 0.077 [95 % CI 0.011, 0.523], p = 0.009) and 24-hour mortality (OR 0.121 [95 % CI 0.019, 0.758], p = 0.024) for every mmol/L increase in iCa. CONCLUSIONS: This study shows the association of hypoCa and traumatic injury. Severe hypoCa was associated with increased odds of early and overall mortality and increased blood product requirements. These results support the need for future prospective trials assessing the role of hypocalcemia in trauma.