Management of Patients With Cardiac Arrest Requiring Interfacility Transport: A Scientific Statement From the American Heart Association.

People who experience out-of-hospital cardiac arrest often require care at a regional center for continued treatment after resuscitation, but many do not initially present to the hospital where they will be admitted. For patients who require interfacility transport after cardiac arrest, the decision to transfer between centers is complex and often based on individual clinical characteristics, resources at the presenting hospital, and available transport resources. Once the decision has been made to transfer a patient after cardiac arrest, there is little direct guidance on how best to provide interfacility transport. Accepting centers depend on transferring emergency departments and emergency medical services professionals to make important and nuanced decisions about postresuscitation care that may determine the efficacy of future treatments. The consequences of early care are greater when transport delays occur, which is common in rural areas or due to inclement weather. Challenges of providing interfacility transfer services for patients who have experienced cardiac arrest include varying expertise of clinicians, differing resources available to them, and nonstandardized communication between transferring and receiving centers. Although many aspects of care are insufficiently studied to determine implications for specific out-of-hospital treatment on outcomes, a general approach of maintaining otherwise recommended postresuscitation care during interfacility transfer is reasonable. This includes close attention to airway, vascular access, ventilator management, sedation, cardiopulmonary monitoring, antiarrhythmic treatments, blood pressure control, temperature control, and metabolic management. Patient stability for transfer, equity and inclusion, and communication also must be considered. Many of these aspects can be delivered by protocol-driven care.

Association Between Emergency Medical Service Agency Volume and Mortality in Trauma Patients.

OBJECTIVE: The aim of this study was to evaluate the association of annual trauma patient volume on outcomes for emergency medical services (EMS) agencies. BACKGROUND: Regionalization of trauma care saves lives. The underlying concept driving this is a volume-outcome relationship. EMS are the entry point to the trauma system, yet it is unknown if a volume-outcome relationship exists for EMS. METHODS: A retrospective analysis of prospective cohort including 8 trauma centers and 20 EMS air medical and metropolitan ground transport agencies. Patients 18 to 90 years old with injury severity scores ≥9 transported from the scene were included. Patient and agency-level risk-adjusted regression determined the association between EMS agency trauma patient volume and early mortality. RESULTS: A total of 33,511 were included with a median EMS agency volume of 374 patients annually (interquartile range: 90-580). Each 50-patient increase in EMS agency volume was associated with 5% decreased odds of 6-hour mortality (adjusted odds ratio=0.95; 95% CI: 0.92-0.99, P =0.03) and 3% decreased odds of 24-hour mortality (adjusted odds ratio=0.97; 95% CI: 0.95-0.99, P =0.04). Prespecified subgroup analysis showed EMS agency volume was associated with reduced odds of mortality for patients with prehospital shock, requiring prehospital airway placement, undergoing air medical transport, and those with traumatic brain injury. Agency-level analysis demonstrated that high-volume (>374 patients/year) EMS agencies had a significantly lower risk-standardized 6-hour mortality rate than low-volume (<374 patients/year) EMS agencies (1.9% vs 4.8%, P <0.01). CONCLUSIONS: A higher volume of trauma patients transported at the EMS agency level is associated with improved early mortality. Further investigation of this volume-outcome relationship is necessary to leverage quality improvement, benchmarking, and educational initiatives.

Early Cold Stored Platelet Transfusion Following Severe Injury: A Randomized Clinical Trial.

OBJECTIVE: To determine the feasibility, efficacy, and safety of early cold stored platelet transfusion compared with standard care resuscitation in patients with hemorrhagic shock. BACKGROUND: Data demonstrating the safety and efficacy of early cold stored platelet transfusion are lacking following severe injury. METHODS: A phase 2, multicenter, randomized, open label, clinical trial was performed at 5 US trauma centers. Injured patients at risk of large volume blood transfusion and the need for hemorrhage control procedures were enrolled and randomized. The intervention was the early transfusion of a single apheresis cold stored platelet unit, stored for up to 14 days versus standard care resuscitation. The primary outcome was feasibility and the principal clinical outcome for efficacy and safety was 24-hour mortality. RESULTS: Mortality at 24 hours was 5.9% in patients who were randomized to early cold stored platelet transfusion compared with 10.2% in the standard care arm (difference, -4.3%; 95% CI, -12.8% to 3.5%; P =0.26). No significant differences were found for any of the prespecified ancillary outcomes. Rates of arterial and/or venous thromboembolism and adverse events did not differ across treatment groups. CONCLUSIONS AND RELEVANCE: In severely injured patients, early cold stored platelet transfusion is feasible, safe and did not result in a significant lower rate of 24-hour mortality. Early cold stored platelet transfusion did not result in a higher incidence of arterial and/or venous thrombotic complications or adverse events. The storage age of the cold stored platelet product was not associated with significant outcome differences. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04667468.

Hypertension during transfer is associated with poor outcomes in unstable patients with ruptured abdominal aortic aneurysm.

OBJECTIVE: Limited data exist for optimal blood pressure (BP) management during transfer of patients with ruptured abdominal aortic aneurysm (rAAA). This study evaluates the effects of hypertension and severe hypotension during interhospital transfers in a cohort of patients with rAAA in hemorrhagic shock. METHODS: We performed a retrospective, single-institution review of patients with rAAA transferred via air ambulance to a quaternary referral center for repair (2003-2019). Vitals were recorded every 5 minutes in transit. Hypertension was defined as a systolic BP of ≥140 mm Hg. The primary cohort included patients with rAAA with hemorrhagic shock (≥1 episode of a systolic BP of <90 mm Hg) during transfer. The primary analysis compared those who experienced any hypertensive episode to those who did not. A secondary analysis evaluated those with either hypertension or severe hypotension <70 mm Hg. The primary outcome was 30-day mortality. RESULTS: Detailed BP data were available for 271 patients, of which 125 (46.1%) had evidence of hemorrhagic shock. The mean age was 74.2 ± 9.1 years, 93 (74.4%) were male, and the median total transport time from helicopter dispatch to arrival at the treatment facility was 65 minutes (interquartile range, 46-79 minutes). Among the cohort with shock, 26.4% (n = 33) had at least one episode of hypertension. There were no significant differences in age, sex, comorbidities, AAA repair type, AAA anatomic location, fluid resuscitation volume, blood transfusion volume, or vasopressor administration between the hypertensive and nonhypertensive groups. Patients with hypertension more frequently received prehospital antihypertensives (15% vs 2%; P = .01) and pain medication (64% vs 24%; P < .001), and had longer transit times (36.3 minutes vs 26.0 minutes; P = .006). Episodes of hypertension were associated with significantly increased 30-day mortality on multivariable logistic regression (adjusted odds ratio [aOR], 4.71; 95% confidence interval [CI], 1.54-14.39; P = .007; 59.4% [n = 19] vs 40.2% [n = 37]; P = .01). Severe hypotension (46%; n = 57) was also associated with higher 30-day mortality (aOR, 2.82; 95% CI, 1.27-6.28; P = .01; 60% [n = 34] vs 32% [n = 22]; P = .01). Those with either hypertension or severe hypotension (54%; n = 66) also had an increased odds of mortality (aOR, 2.95; 95% CI, 1.08-8.11; P = .04; 58% [n = 38] vs 31% [n = 18]; P < .01). Level of hypertension, BP fluctuation, and timing of hypertension were not significantly associated with mortality. CONCLUSIONS: Hypertensive and severely hypotensive episodes during interhospital transfer were independently associated with increased 30-day mortality in patients with rAAA with shock. Hypertension should be avoided in these patients, but permissive hypotension approaches should also maintain systolic BPs above 70 mm Hg whenever possible.

The Role of Integrated Air Transport System in Managing Patients with Abdominal Aortic Aneurysm Rupture.

OBJECTIVE: Ruptured abdominal aortic aneurysms (rAAAs) are highly morbid emergencies. Not all hospitals are equipped to repair them, and an air ambulance network may aid in regionalising specialty care to quaternary referral centres. The association between travel distance by air ambulance and rAAA mortality in patients transferred as an emergency for repair was examined. METHODS: A retrospective review of institutional data. Adults with rAAA (2002 - 2019) transferred from an outside hospital (OSH) to a single quaternary referral centre for repair via air ambulance were identified. Patients who arrived via ground transport or post-repair at an OSH for continued critical care were excluded. Patients were divided into near and far groups based on the 75th percentile of the straight line travel distance (> 72 miles) between hospitals. The primary outcome was 30 day mortality. Multivariable logistic regression was used to assess the association between distance and mortality after adjusting for age, sex, ethnicity, cardiovascular comorbidities, and repair type. RESULTS: A total of 290 patients with rAAA were transported a median distance of 40.4 miles (interquartile range 25.5, 72.7) with 215 (74.1%) near and 75 (25.9%) far patients. Both the near and far groups had similar ages, sex, and ethnicity. There was no difference in pre-operative loss of consciousness, intubation, or cardiac arrest between groups. Endovascular aneurysm repair utilisation and intra-operative aortic occlusion balloon use were also similar. Neither the observed (26.8% vs. 23.9%, p = .61) nor the adjusted odds ratio (0.70, 95% confidence interval 0.36 - 1.39, p = .32) 30 day mortality rate differed significantly between the near and far groups. CONCLUSION: Increasing distance travelled during transfer by air ambulance was not associated with worse outcomes in patients with rAAA. The findings support the regionalisation of rAAA repair to large quaternary centres via an integrated and robust air ambulance network.

Association between First-pass Intubation Success and Enhanced PPE Use during the COVID-19 Pandemic.

OBJECTIVES: We evaluated first-pass endotracheal intubation (ETI) success within the critical care transport (CCT) environment using a natural experiment created by the COVID-19 pandemic. Our primary objective was to evaluate if the use of personal protective equipment (PPE) or the COVID-19 time period was associated with differences in first-pass success rates of ETI within a large CCT system with a high baseline ETI first-pass success rate. We hypothesized that pandemic-related challenges would be associated with decreased first-pass success rates. METHODS: We performed a retrospective before-after cohort study of airway management by CCT personnel relative to the COVID-19 pandemic. We used a mixed effects logistic regression to evaluate the association between enhanced PPE (N95 mask, eye protection) use and the pandemic time period on first-pass intubation success, while controlling for other factors potentially associated with intubation success. Variables in the final model included patient demographics (age, sex, and race), body mass index, medical category (trauma versus non-trauma), interfacility or scene response, blade size (Macintosh 3 versus 4), use of face mask, use of eye protection, and crew member length of service. RESULTS: We identified 1279 cases involving intubation attempts on adult patients during the study period. A total of 1133 cases were included in the final analysis, with an overall first-pass success rate of 95.7% (96.4% pre-COVID-19 and 94.8% during COVID-19). In our final mixed effects logistic regression model, enhanced PPE use and the COVID-19 time period were not associated with first-pass intubation success rate. CONCLUSION: In a large regional CCT system with a high ETI first-pass success rate, neither PPE use nor the COVID-19 time period were associated with differences in ETI first-pass success while controlling for relevant patient and operational factors. Other emergency medical services (EMS) systems may have encountered different effects of pandemic-related PPE use on intubation success rates. Further studies are needed to evaluate the influence of sustained use of enhanced PPE or changes in training or procedural experience on post-pandemic ETI first-pass success rates for non-CCT EMS clinicians.

Defining the Core Content for Transport Physician Training Programs.

In many parts of the world, emergency medical services (EMS) clinical care is traditionally delivered by different levels or types of EMS clinicians, such as emergency medical technicians and paramedics. In some areas, physicians are also included among the cadre of professionals administering EMS-based care. This is especially true in the interfacility transport (IFT) setting. Though there is significant overlap between the knowledge and skills necessary to safely and effectively provide care in the IFT and prehospital settings, the IFT care environment requires physicians to develop several additional competencies beyond those that are expected of traditional EMS clinicians. NAEMSP first published recommendations regarding what some of these competencies should be in 1983 and subsequently updated those recommendations in 2002. This document is an updated work, given the evolution of the field.

Prehospital Electroencephalography to Detect Traumatic Brain Injury during Helicopter Transport: A Pilot Observational Cohort Study.

OBJECTIVE: Early recognition of traumatic brain injury (TBI) is important to facilitate time-sensitive care. Electroencephalography (EEG) can identify TBI, but feasibility of EEG has not been evaluated in prehospital settings. We tested the feasibility of obtaining single-channel EEG during air medical transport after trauma. We measured association between quantitative EEG features, early blood biomarkers, and abnormalities on head computerized tomography (CT). METHODS: We performed a pilot prospective, observational study enrolling consecutive patients transported by critical care air ambulance from the scene of trauma to a Level I trauma center. During transport, prehospital clinicians placed a sensor on the patient's forehead to record EEG. We reviewed EEG waveforms and selected 90 seconds of recording for quantitative analysis. EEG data processing included fast Fourier transform to summarize component frequency power in the delta (0-4 Hz), theta (4-8 Hz), and alpha (8-13 Hz) ranges. We collected blood samples on day 1 and day 3 post-injury and measured plasma levels of two brain injury biomarkers (ubiquitin C-terminal hydrolase L1 [UCH-L1] and glial fibrillary acidic protein [GFAP]). We compared predictors between individuals with and without CT-positive TBI findings. RESULTS: Forty subjects were enrolled, with EEG recordings successfully obtained in 34 (85%). Reasons for failure included uncharged battery (n = 5) and user error (n = 1). Data were lost in three cases. Of 31 subjects with data, interpretable EEG signal was recorded in 26 (84%). Mean age was 48 (SD 16) years, 79% were male, and 50% suffered motor vehicle crashes. Eight subjects (24%) had CT-positive TBI. Subjects with and without CT-positive TBI had similar median delta power, alpha power, and theta power. UCH-L1 and GFAP plasma levels did not differ across groups. Delta power inversely correlated with UCH-L1 day 1 plasma concentration (r = -0.60, p = 0.03). CONCLUSIONS: Prehospital EEG acquisition is feasible during air transport after trauma.

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.

Prehospital Delta Shock Index Predicts Mortality and Need for Life Saving Interventions in Trauma Patients.

OBJECTIVES: The delta shock index (ΔSI), defined as the change in shock index (SI) over time, is associated with hospital morbidity and mortality, but prehospital studies about ΔSI are limited. We investigate the association of prehospital ΔSI with mortality and resource utilization, hypothesizing that increases in SI among field trauma patients are associated with increased mortality and blood product transfusion. METHODS: We performed a multicenter, retrospective, observational study from the Linking Investigators in Trauma and Emergency Services (LITES) network. We obtained data from January 2017 to June 2021. We fit logistic regression models to evaluate the association between an increase ΔSI > 0.1 and 28-day mortality and blood product transfusion within 4 hours of emergency department (ED) arrival. We used negative binomial models to evaluate the association between ΔSI > 0.1 and days in hospital, intensive care unit (ICU), and on ventilator (up to 28 days). RESULTS: We identified 33,219 prehospital patients. We excluded burn patients and those without documented prehospital or ED heart rate or blood pressure, resulting in 30,511 cases for analysis. In adjusted analysis for the primary outcome of 28-day mortality, patients who had a ΔSI > 0.1 based on initial vital signs were 31% more likely to die (adjusted odds ratio (AOR) of 1.31, 95% CI 1.21-1.41) compared to those patients who had a ΔSI ≤0.1. These patients also spent 16% more days in hospital (adjusted incident rate ratio (AIRR) 1.16, 95% CI 1.14-1.19), 34% more days in ICU (AIRR 1.34, 95% CI 1.28-1.41), and 61% more days on ventilator (ARR 1.61, 95% CI 1.47-1.75). Additionally, patients with a ΔSI > 0.1 had higher odds of receiving blood products (AOR 2.00, 95% CI 1.88-2.12) within 4 hours of ED arrival. Models fit excluding hypotensive patients performed similarly. CONCLUSIONS: An increase of greater than 0.1 in the ΔSI was associated with increased 28-day mortality; increased days in hospital, in ICU, and on ventilator; and increased need for blood product transfusion within 4 hours of ED arrival. This association held true for initially normotensive patients. Validation and implementation are needed to incorporate ΔSI into prehospital and ED triage.

Severity-Driven Trends in Mortality in a Large Regionalized Critical Care Transport Service.

OBJECTIVE: The epidemiology accompanying helicopter emergency medical services (HEMS) transport has evolved as agencies have matured and become integrated into regionalized health systems, as evidenced primarily by nationwide systems in Europe. System-level congruence between Europe and the United States, where HEMS is geographically fragmentary, is unclear. In this study, we provide a temporal, epidemiologic characterization of the largest standardized private, nonprofit HEMS system in the United States, STAT MedEvac. METHODS: We obtained comprehensive timing, procedure, and vital signs data from STAT MedEvac prehospital electronic patient care records for all adult patients transported to UPMC Health System hospitals in the period of January 2012 through October 2021. We linked these data with hospital electronic health records available through June 2018 to establish length of stay and vital status at discharge. RESULTS: We studied 90,960 transports and matched 62.8% (n = 57,128) to the electronic health record. The average patient age was 58.6 years ( 19 years), and most were male (57.9%). The majority of cases were interfacility transports (77.6%), and the most common general medical category was nontrauma (72.7%). Sixty-one percent of all patients received a prehospital intervention. Overall, hospital mortality was 15%, and the average hospital length of stay (LOS) was 8.8 days ( 10.0 days). Observed trends over time included increases in nontrauma transports, level of severity, and in-hospital mortality. In multivariable models, case severity and medical category correlated with the outcomes of mortality and LOS. CONCLUSION: In the largest standardized nonprofit HEMS system in the United States, patient mortality and hospital LOS increased over time, whereas the proportion of trauma patients and scene runs decreased.

Prehospital Time Following Traumatic Injury Is Independently Associated With the Need for In-Hospital Blood and Early Mortality for Specific Injury Types.

OBJECTIVE: Treating traumatic hemorrhage is time sensitive. Prehospital care and transport modes (eg, helicopter and ground) may influence in-hospital events. We hypothesized that prehospital time (on-scene time [OST] and total prehospital time [TPT]) and transport mode are associated with same-day transfusion and mortality. Furthermore, we sought to identify regions of anatomic injury that modify the relationship between prehospital time and outcomes in strata corresponding to transport types. METHODS: We obtained prehospital, in-hospital, and trauma registry data from an 8-center cohort of adult nonburn trauma patients from 2017 to 2022 directly transported from the scene to the hospital and having an Injury Severity Score (ISS) > 9 for the Task Order 1 project of the Linking Investigators in Trauma and Emergency Services research network. We excluded patients missing prehospital times, patients < 18 years of age, patients from interfacility transfers, and recipients of prehospital blood. Our same-day outcomes were in-hospital transfusions within 4 hours and 24-hour mortality. Each outcome was adjusted using multivariable logistic regression for covariates of prehospital phases (OST and TPT), mode of transport (helicopter and ground), age, sex, ISS, Glasgow Coma Scale motor subscale score < 6, and field hypotension (systolic blood pressure < 90 mm Hg). We evaluated the association of prehospital time on outcomes for scene missions by transport mode across severe injury patterns defined by Abbreviated Injury Scale > 2 body regions. RESULTS: Of 78,198 subjects, 34,504 were eligible for the study with a mean age of 47.6 ± 20.3 years, ISS of 18 ± 11, OST of 15.9 ± 9.5 minutes, and TPT of 48.7 ± 20.3 minutes. Adjusted for injury severity and demographic factors, transport type significantly modified the relationship between prehospital time and outcomes. The association of OST and TPT with the odds of 4-hour transfusion was absent for the ground emergency medical services (GEMS) cohort and present for the helicopter emergency medical services (HEMS) ambulance cohort, whereas these times were associated with decreased 24-hour mortality for both transport types. When stratifying by injury to most anatomic regions, OST and TPT were associated with a decreased need for 4-hour transfusions in the GEMS cohort. However, OST was associated with increased early transfusion only among patients with severe injuries of the thorax, and this association persisted after adjusting additionally for injury type (odds ratio [OR] = 1.03; 95% confidence interval [CI], 1.00-1.05; P = .02). The presence of polytrauma supported an association between prehospital time and decreased 24-hour mortality for the GEMS cohort (OST: OR = 0.97; 95% CI, 0.95-0.99; P < .01; TPT: OR = 0.99; 95% CI, 0.98-0.99; P = .02), whereas no injuries showed significant association of helicopter prehospital time on mortality after adjustment. CONCLUSION: We determined that transport type affects the relationship between prehospital time and hospital outcomes (4-hour transfusion: positive relationship for HEMS and negative for GEMS, 24-hour mortality: negative for both transport types). Furthermore, we identified regions of anatomic injury that modify the relationship between prehospital time and outcomes in strata corresponding to transport types. Of these regions, most notable were severe isolated injuries to the thorax that supported a positive relationship between HEMS OST and 4-hour transfusions and polytrauma that showed a negative relationship between GEMS OST or TPT and 24-hour mortality after adjustment.

The Geography of Injuries in Trauma Systems: Using Home as a Proxy for Incident Location.

INTRODUCTION: Effective trauma system organization is crucial to timely access to care and requires accurate understanding of injury and resource locations. Many systems rely on home zip codes to evaluate geographic distribution of injury; however, few studies have evaluated the reliability of home as a proxy for incident location after injury. METHODS: We analyzed data from a multicenter prospective cohort collected from 2017 to 2021. Injured patients with both home and incident zip codes were included. Outcomes included discordance and differential distance between home and incident zip code. Associations of discordance with patient characteristics were determined by logistic regression. We also assessed trauma center catchment areas based on home versus incident zip codes and variation regionally at each center. RESULTS: Fifty thousand one hundred seventy-five patients were included in the analysis. Home and incident zip codes were discordant in 21,635 patients (43.1%). Injuries related to motor vehicles (aOR: 4.76 [95% CI 4.50-5.04]) and younger adults 16-64 (aOR: 2.46 [95% CI 2.28-2.65]) were most likely to be discordant. Additionally, as injury severity score increased, discordance increased. Trauma center catchment area differed up to two-thirds of zip codes when using home versus incident location. Discordance rate, discordant distance, and catchment area overlap between home and incident zip codes all varied significantly by geographic region. CONCLUSIONS: Home location as proxy for injury location should be used with caution and may impact trauma system planning and policy, especially in certain populations. More accurate geolocation data are warranted to further optimize trauma system design.

High Dimensional Multiomics Reveals Unique Characteristics of Early Plasma Administration in Polytrauma Patients With TBI.

OBJECTIVES: The authors sought to identify causal factors that explain the selective benefit of prehospital administration of thawed plasma (TP) in traumatic brain injury (TBI) patients using mediation analysis of a multiomic database. BACKGROUND: The Prehospital Air Medical Plasma (PAMPer) Trial showed that patients with TBI and a pronounced systemic response to injury [defined as endotype 2 (E2)], have a survival benefit from prehospital administration of TP. An interrogation of high dimensional proteomics, lipidomics and metabolomics previously demonstrated unique patterns in circulating biomarkers in patients receiving prehospital TP, suggesting that a deeper analysis could reveal causal features specific to TBI patients. METHODS: A novel proteomic database (SomaLogic Inc., aptamer-based assay, 7K platform) was generated using admission blood samples from a subset of patients (n=149) from the PAMPer Trial. This proteomic dataset was combined with previously reported metabolomic and lipidomic datasets from these same patients. A 2-step analysis was performed to identify factors that promote survival in E2-TBI patients who had received early TP. First, features were selected using both linear and multivariate-latent-factor regression analyses. Then, the selected features were entered into the causal mediation analysis. RESULTS: Causal mediation analysis of observable features identified 16 proteins and 41 lipids with a high proportion of mediated effect (>50%) to explain the survival benefit of early TP in E2-TBI patients. The multivariate latent-factor regression analyses also uncovered 5 latent clusters of features with a proportion effect >30%, many in common with the observable features. Among the observable and latent features were protease inhibitors known to inhibit activated protein C and block fibrinolysis (SERPINA5 and CPB2), a clotting factor (factor XI), as well as proteins involved in lipid transport and metabolism (APOE3 and sPLA(2)-XIIA). CONCLUSIONS: These findings suggest that severely injured patients with TBI process exogenous plasma differently than those without TBI. The beneficial effects of early TP in E2-TBI patients may be the result of improved blood clotting and the effect of brain protective factors independent of coagulation.

Interfacility Transport of Critically Ill Patients.

OBJECTIVES: To assess recent advances in interfacility critical care transport. DATA SOURCES: PubMed English language publications plus chapters and professional organization publications. STUDY SELECTION: Manuscripts including practice manuals and standard (1990-2021) focused on interfacility transport of critically ill patients. DATA EXTRACTION: Review of society guidelines, legislative requirements, objective measures of outcomes, and transport practice standards occurred in work groups assessing definitions and foundations of interfacility transport, transport team composition, and transport specific considerations. Qualitative analysis was performed to characterize current science regarding interfacility transport. DATA SYNTHESIS: The Task Force conducted an integrative review of 496 manuscripts combined with 120 from the authors' collections including nonpeer reviewed publications. After title and abstract screening, 40 underwent full-text review, of which 21 remained for qualitative synthesis. CONCLUSIONS: Since 2004, there have been numerous advances in critical care interfacility transport. Clinical deterioration may be mitigated by appropriate patient selection, pretransport optimization, and transport by a well-resourced team and vehicle. There remains a dearth of high-quality controlled studies, but notable advances in monitoring, en route management, transport modality (air vs ground), as well as team composition and training serve as foundations for future inquiry. Guidance from professional organizations remains uncoupled from enforceable regulations, impeding standardization of transport program quality assessment and verification.

Implementation and challenges of portable blood gas measurements in air medical transport.

OBJECTIVES: Ventilator management in prehospital settings using end-tidal CO2 can lead to inappropriate ventilation in the absence of point of care blood gas (POCBG) measurements. Implementation of POCBG testing in helicopter Emergency Medical Services (HEMS) is limited in part because of concern for preanalytical and analytical errors due to altitude, vibration, and other associated environmental factors and due to insufficient documentation of implementation challenges. METHODS: We performed accuracy and precision verification studies using standard materials tested pre-, in-, and post-flight (n=10) in a large HEMS agency. Quality assurance error log data were extracted and summarized for common POCBG errors during the first 31 months of use and air medical transport personnel were surveyed regarding POCBG use (n=63). RESULTS: No clinically significant differences were found between pre-, in-, and post-flight blood gas measurements. Error log data demonstrated a reduction in device errors over time. Survey participants found troubleshooting device errors and learning new clinical processes to be the largest barriers to implementation. Continued challenges for participants coincided with error log data including temperature and sampling difficulties. Survey participants indicated that POCBG testing improved patient management. CONCLUSIONS: POCBG testing does not appear to be compromised by the HEMS environment. Temperature excursions can be reduced by use of insulated transport bags with heating and cooling packs. Availability of POCBG results in air medical transport appeared to improve ventilator management, increase recognition of ventilation-perfusion mismatch, and improve patient tolerance of ventilation.

Prehospital Manual Ventilation: An NAEMSP Position Statement and Resource Document.

Manual ventilation using a self-inflating bag device paired with a facemask (bag-valve-mask, or BVM ventilation) or invasive airway (bag-valve-device, or BVD ventilation) is a fundamental airway management skill for all Emergency Medical Services (EMS) clinicians. Delivery of manual ventilations is challenging. Several strategies and adjunct technologies can increase the effectiveness of manual ventilation. NAEMSP recommends:All EMS clinicians must be proficient in bag-valve-mask ventilation.BVM ventilation should be performed using a two-person technique whenever feasible.EMS clinicians should use available techniques and adjuncts to achieve optimal mask seal, improve airway patency, optimize delivery of the correct rate, tidal volume, and pressure during manual ventilation, and allow continual assessment of manual ventilation effectiveness.

The Effect of Blood Transfusion during Air Medical Transport on Transport Times in Patients with Ruptured Abdominal Aortic Aneurysm.

Background: Patients presenting with a diagnosis of ruptured abdominal aortic aneurysm (RAAA) to community hospitals must be transported to tertiary care centers, where necessary resources are available. Unfortunately, guidelines for treatment of RAAA lack high-level evidence on the optimal resuscitation of RAAA patients during transport. We hypothesized that transfusion of packed red blood cells (PRBCs) during transport would not delay transport times in patients with RAAA. Methods: We performed a retrospective analysis of a prospective registry including prehospital data of patients with RAAA presenting to a single academic hospital in Western Pennsylvania between 2001 and 2019. Our primary outcomes were prehospital transport times: "transport interval" and "total interval." "Transport interval" is the duration from patient pickup at the outside hospital (OSH) to arrival at the receiving facility. "Total interval" is the duration from dispatch of the air medical transport to arrival of the patient to the receiving facility. We then compared two groups of patients, stratified by the receipt of PRBCs in transit, by reporting mean difference (95% confidence interval: CI) for continuous variables and percent difference (95% CI) for categorical variables. We performed two multivariate linear regression models to test if there was any effect of the receipt of PRBCs in transit on transport times. Results: We included 271 patients with RAAA transported by our air ambulance system who underwent an operation at the receiving facility, 99 (37%) of whom received PRBCs in transit. Mean ± standard deviation (SD) of the total intervals were 67 ± 28 and 71 ± 42 minutes, among patients who received or did not receive PRBCs in transit respectively, with no significant difference (p = 0.437). Following adjusted analysis, the receipt of PRBCs during transport was not associated with increased transport times, after accounting for age, hypotension, endovascular aneurysm repair (EVAR), and PRBC transfusion at the OSH. Conclusion: PRBC transfusion during air medical transport in patients with RAAA did not delay transport times.

Prehospital Trauma Airway Management: An NAEMSP Position Statement and Resource Document.

Definitive management of trauma is not possible in the out-of-hospital environment. Rapid treatment and transport of trauma casualties to a trauma center are vital to improve survival and outcomes. Prioritization and management of airway, oxygenation, ventilation, protection from gross aspiration, and physiologic optimization must be balanced against timely patient delivery to definitive care. The optimal prehospital airway management strategy for trauma has not been clearly defined; the best choice should be patient-specific. NAEMSP recommends:The approach to airway management and the choice of airway interventions in a trauma patient requires an iterative, individualized assessment that considers patient, clinician, and environmental factors.Optimal trauma airway management should focus on meeting the goals of adequate oxygenation and ventilation rather than on specific interventions. Emergency medical services (EMS) clinicians should perform frequent reassessments to determine if there is a need to escalate from basic to advanced airway interventions.Management of immediately life-threatening injuries should take priority over advanced airway insertion.Drug-assisted airway management should be considered within a comprehensive algorithm incorporating failed airway options and balanced management of pain, agitation, and delirium.EMS medical directors must be highly engaged in assuring clinician competence in trauma airway assessment, management, and interventions.

Prehospital Noninvasive Ventilation: An NAEMSP Position Statement and Resource Document.

Noninvasive ventilation (NIV), including bilevel positive airway pressure and continuous positive airway pressure, is a safe and important therapeutic option in the management of prehospital respiratory distress. NAEMSP recommends:NIV should be used in the management of prehospital patients with respiratory failure, such as those with chronic obstructive pulmonary disease, asthma, and pulmonary edema.NIV is a safe intervention for use by Emergency Medical Technicians.Medical directors must assure adequate training in NIV, including appropriate patient selection, NIV system operation, administration of adjunctive medications, and assessment of clinical response.Medical directors must implement quality assessment and improvement programs to assure optimal application of and outcomes from NIV.Novel NIV methods such as high-flow nasal cannula and helmet ventilation may have a role in prehospital care.