Appropriate Air Medical Services Utilization and Recommendations for Integration of Air Medical Services Resources into the EMS System of Care: A Joint Position Statement and Resource Document of NAEMSP, ACEP, and AMPA.

This update to the 2013 joint position statement, Appropriate and Safe Utilization of Helicopter Emergency Medical Services, provides guidance for air medical services utilization based on currently available evidence. Air medical services utilization considerations fall into three major categories: clinical considerations, safety considerations, and system integration and quality assurance.Clinically, air medical services should accomplish one or more of three primary patient-centered goals: initiation or continuation of locally unavailable advanced or specialty care; expedited delivery to definitive care for time-sensitive interventions; and/or extraction from physically remote or otherwise inaccessible locations that limit timely access to necessary care. Ground-EMS (GEMS) transport is preferred when it is able to provide the necessary level of care and timely transport to definitive care.Risk identification and safety of both the patient and crew must be uniformly balanced against the anticipated degree of patient medical benefit. While auto-ready and auto-launch practices may increase access to air medical services, they also risk over-use, and so must be rigorously reviewed. Safety is enhanced during multi-agency emergency responses by coordinated interagency communication, ideally through centralized communication centers. Helicopter shopping and reverse helicopter shopping both create significant safety risks and their use is discouraged.Regional EMS systems must integrate air medical services to facilitate appropriate utilization in alignment with the primary patient goals while being cognizant of local indications, resources, and needs. To maximize consistent, informed air medical services utilization decisions, specific indications for and limitations to air medical services utilization that align with local and regional system and patient needs should be identified, and requests routed through centralized coordinating centers supported by EMS physicians.To limit risk and promote appropriate utilization of air medical services, GEMS clinicians should be encouraged to cancel an air medical services response if it is not aligned with at least one of the three primary patient-centered goals. Similarly, air medical services clinicians should be empowered to redirect patient transport to GEMS. Air medical services should not routinely be used solely to allow GEMS to remain in their primary service area.

Prehospital Point of Care Testing for the Early Detection of Shock and Prediction of Lifesaving Interventions.

INTRODUCTION: Early diagnosis and treatment are essential for enhancing outcomes for the traumatically injured. In this prospective prehospital observational study, we hypothesized that a variety of laboratory results measured in the prehospital environment would predict both the presence of early shock and the need for lifesaving interventions (LSIs) for adult patients with traumatic injuries. METHODS: Adult trauma patients flown by a helicopter emergency medical service were prospectively enrolled. Using an i-STAT portable analyzer, data from 16 laboratory tests were collected. Vital signs data were also collected. Outcomes of interest included detection of shock, mortality, and requirement for LSIs. Logistic regression, including a Bayesian analysis, was performed. RESULTS: Among 300 patients screened for enrollment, 261 had complete laboratory data for analysis. The majority of patients were male (75%) with blunt trauma (91.2%). The median injury severity score was 29 (IQR, 25-75) and overall mortality was 4.6%. A total of 170 LSIs were performed. The median lactate for patients who required an LSI was 4.1 (IQR, 3-5.4). The odds of requiring an LSI within the first hour of admission to the trauma center was highly associated with increases in lactate and glucose. A lactate level > 4 mmol/L was statistically associated with greater sensitivity and specificity for predicting the need for a LSI compared with shock index. CONCLUSIONS: In this prospective observational trial, lactate outperformed static vital signs, including shock index, for detecting shock and predicting the need for LSIs. A lactate level > 4 mmol/L was found to be highly associated with the need for LSIs.

Handheld Tissue Oximetry for the Prehospital Detection of Shock and Need for Lifesaving Interventions: Technology in Search of an Indication?

Improved prehospital methods for assessing the need for lifesaving interventions (LSIs) are needed to gain critical lead time in the care of the injured. We hypothesized that threshold values using prehospital handheld tissue oximetry would detect occult shock and predict LSI requirements. This was a prospective observational study of adult trauma patients emergently transported by helicopter. Patients were monitored with a handheld tissue oximeter (InSpectra Spot Check; Hutchinson Technology Inc, Hutchinson, MN), continuous vital signs, and 21 laboratory measurements obtained both in the field with a portable analyzer and at the time of admission. Shock was defined as base excess ≥ 4 or lactate > 3 mmol/L. Eighty-eight patients were enrolled with a median Injury Severity Score of 16 (interquartile range, 5-29). The median hemoglobin saturation in the capillaries, venules, and arterioles (StO2) value for all patients was 82% (interquartile range, 76%-87%; range, 42%-98%). StO2 was abnormal (< 75%) in 18 patients (20%). Eight were hypotensive (9%) and had laboratory-confirmed evidence of occult shock. StO2 correlated poorly with shock threshold laboratory values (r = -0.17; 95% confidence interval, -0.33 to 1.0; P = .94). The area under the receiver operating curve was 0.51 (95% confidence interval, 0.39-0.63) for StO2 < 75% and laboratory-confirmed shock. StO2 was not associated with LSI need on admission when adjusted for multiple covariates, nor was it independently associated with death. Handheld tissue oximetry was not sensitive or specific for identifying patients with prehospital occult shock. These results do not support prehospital StO2 monitoring despite its inclusion in several published guidelines.

Maryland's Helicopter Emergency Medical Services Experience From 2001 to 2011: System Improvements and Patients' Outcomes.

STUDY OBJECTIVE: Helicopter emergency medical services (EMS) has become a well-established component of modern trauma systems. It is an expensive, limited resource with potential safety concerns. Helicopter EMS activation criteria intended to increase efficiency and reduce inappropriate use remain elusive and difficult to measure. This study evaluates the effect of statewide field trauma triage changes on helicopter EMS use and patient outcomes. METHODS: Data were extracted from the helicopter EMS computer-aided dispatch database for in-state scene flights and from the state Trauma Registry for all trauma patients directly admitted from the scene or transferred to trauma centers from July 1, 2000, to June 30, 2011. Computer-aided dispatch flights were analyzed for periods corresponding to field triage protocol modifications intended to improve system efficiency. Outcomes were separately analyzed for trauma registry patients by mode of transport. RESULTS: The helicopter EMS computer-aided dispatch data set included 44,073 transports. There was a statewide decrease in helicopter EMS usage for trauma patients of 55.9%, differentially affecting counties closer to trauma centers. The Trauma Registry data set included 182,809 patients (37,407 helicopter transports, 128,129 ambulance transports, and 17,273 transfers). There was an increase of 21% in overall annual EMS scene trauma patients transported; ground transports increased by 33%, whereas helicopter EMS transports decreased by 49%. Helicopter EMS patient acuity increased, with an attendant increase in patient mortality. However, when standardized with W statistics, both helicopter EMS- and ground-transported trauma patients showed sustained improvement in mortality. CONCLUSION: Modifications to state protocols were associated with decreased helicopter EMS use and overall improved trauma patient outcomes.

Ground and Helicopter Emergency Medical Services Time Tradeoffs Assessed with Geographic Information.

INTRODUCTION: We describe how geographic information systems (GIS) can be used to assess and compare estimated transport time for helicopter and ground emergency medical services. Recent research shows that while the odds of a trauma patient's survival increase with helicopter emergency medical services (HEMS), they may not increase to the extent necessary to make HEMS cost effective. This study offers an analytic tool to objectively quantify the patient travel time advantage that HEMS offers compared to ground emergency medical services (GEMS). METHODS: Using helicopter dispatch data from the Maryland State Police from 2000-2011, we computed transport time estimates for HEMS and GEMS, compare these results to a reference transport time of 60 min, and use geospatial interpolation to extrapolate the total response times for each mode across the study region. RESULTS: Mapping the region's trauma incidents and modeling response times, our findings indicate the GIS framework for calculating transportation time tradeoffs is useful in identifying which areas can be better served by HEMS or GEMS. DISCUSSION: The use of GIS and the analytical methodology described in this study present a method to compare transportation by air and ground in the prehospital setting that accounts for how mode, distance, and road infrastructure impact total transport time. Whether used to generate regional maps in advance or applied real-time, the presented framework provides a tool to identify earlier incident locations that favor HEMS over GEMS transport modes.

Appropriate and safe utilization of helicopter emergency medical services: a joint position statement with resource document.

This position statement with accompanying resource document is the result of a collaborative effort of a writing group comprised of members of the Air Medical Physician Association (AMPA), the American College of Emergency Physicians (ACEP), the National Association of EMS Physicians (NAEMSP), and the American Academy of Emergency Medicine (AAEM). This document has been jointly approved by the boards of all four organizations. Patients benefit from the appropriate utilization of helicopter emergency medical services (HEMS). EMS and regional health care systems must have and follow guidelines for HEMS utilization to facilitate proper patient selection and ensure clinical benefit. Clinical benefit can be provided by Meaningfully shortening the time to delivery of definitive care to patients with time-sensitive medical conditions Providing necessary specialized medical expertise or equipment to patients before and/or during transport Providing transport to patients inaccessible by other means of transport The decision to use HEMS is a medical decision, separate from the aviation determination whether a transport can be completed safely. Physicians with specialized training and experience in EMS and air medical transport must be integral to HEMS utilization decisions, including guideline development and quality improvement activities. Safety management systems must be developed, adopted, and adhered to by air medical operators when making decisions to accept and continue every HEMS transport. HEMS must be fully integrated within the local, regional, and state emergency health care systems. HEMS programs cannot operate independently of the surrounding health care environment. The EMS and health care systems must be involved in the determination of the number of HEMS assets necessary to provide appropriate coverage for their region. Excessive resources may lead to competitive practices that can affect utilization and negatively impact safety. Inadequate resources will delay receipt of definitive care. National guidelines for appropriate utilization of HEMS must be developed. These guidelines should be national in scope yet allow local, regional, and state implementation. A National HEMS Agenda for the Future should be developed to address HEMS utilization and availability and to identify and support a research strategy for ongoing, evidence-based refinement of utilization guidelines.

Prehospital hypocapnia and poor outcome after severe traumatic brain injury.

BACKGROUND: The Brain Trauma Foundation (BTF) Guidelines for prehospital management of traumatic brain injury (TBI) recommend a goal end-tidal carbon dioxide of 30 mm Hg to 35 mm Hg in patients without signs of herniation. METHODS: We examined prehospital concordance with BTF Guidelines, selected demographic and physiologic variables and outcomes for 100 consecutive admissions to a well-established Level I regional trauma center. All patients had blunt TBI with Glasgow Coma Score < or = 8 without signs of herniation. All were transported by helicopter by flight paramedics experienced with BTF Guidelines and the continuous wave form capnometer. Patients resumed spontaneous ventilation after intubation. RESULTS: Concordance (prehospital end-tidal carbon dioxide > 29 mm Hg) was achieved in 65 of 100 cases. Mortality was 29% (19 of 65) among those in whom guideline levels were achieved prehospital and 46% (16 of 35) in those in whom guideline levels were not achieved prehospital (odds ratio, 0.49; p = 0.10). The "achieved" group was younger (p = 0.02), with higher calculated probability of survival (p = 0.01). Intracranial pressure was maintained under intensive care within acceptable limits in the hospital in both groups but was significantly higher in the "not achieved" group (p = 0.05). CONCLUSIONS: Our data, though not statistically significant, suggest that patients who are harder to keep within the guidelines in the field are more likely to die, because of more severe TBI or complication by other factors such as age or injury severity. Whether increased awareness of this phenomenon can improve outcomes is unknown but suggests an approach to future education and research.

A regional system of stroke care provides thrombolytic outcomes comparable with the NINDS stroke trial.

STUDY OBJECTIVE: Administration of tissue plasminogen activator (tPA) for acute ischemic stroke remains controversial in community practice. Well-organized hierarchic systems of acute stroke care have been proposed to link community hospitals to comprehensive stroke centers. We report safety and functional outcomes in patients treated with tPA in our regional emergency stroke network and compare them with results reported from the trial conducted by the National Institute of Neurological Disorders and Stroke (NINDS). METHODS: Through a statewide communications and transport network, our brain attack center gives emergency medicine staff in the state and surrounding area immediate access to stroke specialists. The team provides consultation about the administration of tPA for ischemic stroke, using the NINDS protocol. Consultations, treatment, and outcomes are documented in our database. RESULTS: From 1996 to 2005, the brain attack center completed 2,670 consultations and diagnosed 1,788 patients with ischemic stroke. Two hundred forty patients (9% of all consultations; 13.4% of those with acute ischemic stroke) received tPA. Percentages of patients with symptomatic intracranial hemorrhage and 3-month modified Rankin scale scores less than or equal to 1, compared with those in the NINDS trial, were as follows: 3.3% versus 6.4% and 53% versus 43% (P=.04). Mortality rates were 13% (network) versus 17% (NINDS). CONCLUSION: During a 9-year period, an emergency medicine network with stroke consultants achieved patient outcomes comparable to those reported from the NINDS trial. These results indicate that the NINDS tPA protocol is applicable to community practice, with the support of a university-based brain attack center.

Flicker illness: an underrecognized but preventable complication of helicopter transport.

A case report of seizure due to photic stimulation from sunlight shining through spinning helicopter rotor blades is discussed. A review of photosensitive epilepsy is provided with particular emphasis on the effects and frequencies of photic stimulation required to induce symptoms. The frequencies of flashing light produced by spinning helicopter rotor blades commonly used in air medical transport range from 24 to 27 flashes per second. These frequencies are well within the range reported in the literature to produce symptoms in the laboratory setting. The literature provides only a few case reports of individuals sustaining a seizure after photic stimulation from spinning turboprop or helicopter blades. Symptoms range from mild discomfort and headache to profound spatial disorientation and seizures and may be an underrecognized but preventable complication of air medical transport.