Douglas J. Floccare

INTER-RATER RELIABILITY OF PREVENTABLE DEATH JUDGMENTS

This study examined the inter-rater reliability of preventable death judgments for trauma. A total of 130 deaths were reviewed for potential preventability by multiple panels of nationally chosen experts. Deaths involving a central nervous system (CNS) injury were reviewed by three panels, each consisting of a trauma surgeon, a neurosurgeon, and an emergency physician. Deaths not involving the CNS were reviewed by three panels, each consisting of two trauma surgeons and an emergency physician. Cases for review were sampled from all hospital trauma deaths occurring in Maryland during 1986. Panels were given prehospital and hospital records, medical examiner reports, and autopsy reports, and asked to independently classify deaths as not preventable (NP), possibly preventable (POSS), probably preventable (PROB), or definitely preventable (DEF). Cases in which there was disagreement about preventability were discussed by the panel as a group (via conference call). Results indicated that overall reliability was low. All three panels reviewing non-CNS deaths agreed in only 36% of the cases (kappa = 0.21). Agreement among panels reviewing CNS deaths was somewhat higher at 56% (kappa = 0.40). Most of the disagreements, however, were in judging whether deaths were NP or POSS. Agreement was higher for early deaths and less severely injured patients. For non-CNS deaths agreement was also higher for younger patients. When both autopsy results and prehospital care reports were available reliability increased across panels. A variety of approaches have been used to elicit judgments of preventability. This study provides information to guide recommendations for future studies involving implicit judgments of preventable death.

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.

Appropriate and Safe Utilization of Helicopter Emergency Medical Services: A Joint Position Statement with Resource Document

Abstract 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. Key words: appropriateness; helicopter; HEMS; safety; utilization

Identification of dynamic prehospital changes with continuous vital signs acquisition.

OBJECTIVE In most trauma registries, prehospital trauma data are often missing or unreliable because of the difficult dual task consigned to prehospital providers of recording vital signs and simultaneously resuscitating patients. The purpose of this study was to test the hypothesis that the analysis of continuous vital signs acquired automatically, without prehospital provider input, improves vital signs data quality, captures more extreme values that might be missed with conventional human data recording, and changes Trauma Injury Severity Scores compared with retrospectively compiled prehospital trauma registry data. METHODS A statewide vital signs collection network in 6 medevac helicopters was deployed for prehospital vital signs acquisition using a locally built vital signs data recorder (VSDR) to capture continuous vital signs from the patient monitor onto a memory card. VSDR vital signs data were assessed by 3 raters, and intraclass correlation coefficients were calculated to test interrater reliability. Agreement between VSDR and trauma registry data was compared with the methods of Altman and Bland including corresponding calculations for precision and bias. RESULTS Automated prehospital continuous VSDR data were collected in 177 patients. There was good agreement between the first recorded vital signs from the VSDR and the trauma registry value. Significant differences were observed between the highest and lowest heart rate, systolic blood pressure, and pulse oximeter from the VSDR and the trauma registry data (P< .001). Trauma Injury Severity Scores changed in 12 patients (7%) when using data from the VSDR. CONCLUSION Real-time continuous vital signs monitoring and data acquisition can identify dynamic prehospital changes, which may be missed compared with vital signs recorded manually during distinct prehospital intervals. In the future, the use of automated vital signs trending may improve the quality of data reported for inclusion in trauma registries. These data may be used to develop improved triage algorithms aimed at optimizing resource use and enhancing 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 patients 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 regions 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.

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 andfrequencies 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 andheadache to profound spatial disorientation andseizures andmay be an underrecognized but preventable complication of air medical transport.

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.

Impact of prehospital mode of transport after severe injuries: reevaluation of results.

To the Editor: Bulger et al. report on a multicenter retrospective analysis of 2,049 patients with major trauma and transported by either air (n = 703) or ground (n = 1,346). In the multivariable analysis, air transportation was found to be associated with improved 28-day and 24-hour survival, but these results failed to reach statistical significance perhaps owing to the underpowered nature of the study. The total number of patients in this study was 2,049; yet, to detect up to a 5% survival advantage in either the ground or air cohort, with 80% power and an > of 0.05, at least 2,526 subjects would have be enrolled; a far greater number of subjects would have be enrolled to detect even smaller differences in survival. Of the 703 air transport patients, 60% came from three trauma centers (Dallas/Fort Worth, Seattle/King County, and Toronto, Canada). Hence, the results from this study may not be externally generalizable. As the authors point out, multivariable techniques only account for known confounders, and although the authors did an admirable job including important independent variables, other unmeasured variables may explain the results. For example, the mean out-of-hospital time was 76.1 minutes for the air transport group compared with 43.5 minutes in the ground transport group (p G 0.0001). This difference in time between cohorts is difficult to assess in the absence of distance information. The authors acknowledge this limitation, and the relation between out-of-hospital time and distance remains unknown. Distance may be one of the several unmeasured confounders in this study. Most of the available evidence supports a role for air transport when patients are severely injured, and not in proximity to a trauma center. In the most adequately powered regression-based studies to date, helicopter transport improves survival. Indeed, any benefit to air transport is likely some combination of speed, crew expertise, and the fact that air transport is a highly integrated part of contemporary trauma systems. Furthermore, when appropriately applied to injured patients, air transport should give patients who are not near a trauma center an equivalent rate of survival as those who are already in proximity to expert care. There is no reason to hypothesize that these patients should have a better outcome; rather, air transport should simply afford these patients an equivalent opportunity for good outcome. Given the infeasibility and ethical concerns about performing randomized controlled trials in this area, the use of advanced statistical methods for observational research, such as propensity scores and instrumental variables, should be considered the standard for analyzing the data from future air transport studies.