healthy volunteers following the administration of 4.8 mg of nitroglycerin given over 25 m i n u t e s (12 sublingual tablets, each containing 0.4 rag}. Eleven male volunteers ages 19-38 years took 6 sublingual doses of 0.8 mg (2 tablets) every 5 minutes. Venous blood was drawn by heparin lock at 0 and 3 minutes, and then every 5 m i n u t e s for 1 hour after the 3-minute sample. Bradycardia and h y p o t e n s i o n in 1 subject necessitated his withdrawal from the protocol. The highest methemoglobin level achieved by any subject was 1.6%. The results suggest that higher doses of nitroglycerin can be a d m i n i s t e r e d w i t h o u t u n d u e elevation of methemoglobin levels. Idiosyncratic reactions may, however, occur, in w h i c h enzyme deficiency can lead to abnormal sensitivity to the drug. Our results also would Suggest that nitroglycerin is of little value in the prehospital or hospital t r e a t m e n t of cyanide toxicity in w h i c h the goal is to raise quickly m e t h e m o g l o b i n levels.
101
Serum Concentrations of Meperidine in Patients with Sickle Cell Disease
S Abbuhl, S Jacobson, JG Murphy, G Gibson / Emergency Services Department and Pharmacy and Drug Information Service, Hospital of the University of Pennsylvania, Philadelphia We compared m e a n s e r u m c o n c e n t r a t i o n s of meperidine in sickle cell patients in crisis (SS) and control patients (CON) receiving meperidine prior to incision and drainage of abscesses. Eight SS and 5 C O N patients w i t h o u t confounding illnesses Consented to participate. They received 100 mg of meperidine in the deltoid or gluteal muscle for pain. Induration that m i g h t interfere with the medication's absorption was assessed w i t h respect to the site of each injection. Blood samples were drawn at baseline, V4, ~/2, 3/4, 1, 11/2, and 2 h postinjeetion. Serum samples were coded and blinded; gas-liquid c h r o m a t o g r a p h y was used to quantify meperidine levels. In the SS group, m e a n peak concentration of meperidine was 0.324 + .08 ~g/mL at an average of 0.5 -+ 0.07 h postinjection. Among CON, m e a n peak concentration was 0.727 +- 0.37 tzg/mL at an average of 0.6 + 0,11 h. The difference in peak concentrations of meperidine was significantly different (t = 2.96; df = 11; P < .01); the difference in times to peaks was not significant {t = 0.65). Differences between groups for serum concentrations were significantly different both at V~h (P < .001) and at 1 h (P < .05). Changes w i t h i n each group between 1/2 h and 1 h were not significant (P > .30). Presence of induration at the injection site was more frequent among SS than CON, but the difference was not statistically significant (chi-square = 1.11). We conclude that, given a standard dose, s e r u m c o n c e n t r a t i o n s of meperidine differ between SS patients and C O N patients. Further evaluation is needed to explain observed differences. These results m a y suggest reasons for the relatively poor pain control often noted in SS patients.
102
Utilization of Computer Simulation to Enhance Mass Casualty Incident Response Skills
RD Kelley, KC Harrison, SM Lyon, LC Baldwin, CR Hansen/ Quintessential Mass Casualty Consultants, San Clemente, California During the years 1980 to 1984, a series of mas s casualty incident exercises involving 50 to 400 moulaged victims were cond u c t e d in Orange County, California. Each series exercised m a n a g e m e n t theories and response concepts for a coordinated agency response to a mass casualty incident (MCI). The principal goal of these field exercises was to decrease actual MCI victim mortality and morbidity by increasing MCI response skills. The basic mass casualty response skills of i n c i d e n t scene management, field triage, hospital patient care capacity estimation, patient field dispatch priority, and resource depletion anticipation were presented prior to each exercise. Analysis by the respective planning committees for every exercise stressed the importance
14:5 May 1985
of more and effective education of these skills to all responding agency participants. To meet these needs w i t h computer technology, an MCI simulation program was developed. The object of the simulation is to decrease the mortality and morbidity to all victims of the simulation scenario through the choice of recom* m e n d e d basic mass casualty response teaching points. These teaching points reflect established and theoretical procedures for MCI mitigation. Although computer simulation programs have been developed for use during MCI operations, this simulation is one of the earliest prototypes for use in disaster medical education. T h i s and more sophisticated revisions of c o m p u t e r MCI simulation programs can be utilized to maximize the learning experience during field exercises before personnel and materiel are c o m m i t t e d to these large and expensive events. Most important, utilization can enhance and m a i n t a i n skills after such field exercises in the hope of decreasing mortality and morbidity during actual mass casualty incidents.
103
Disposition of Patients Referred from Freestanding Emergency Centers to a Hospital Emergency Department
LJ Ling, I Gold / Department of Emergency Medicine, Hennepin County Medical Center, Minneapolis; Division of Emergency Medicine, Mercy Hospital and Medical Center, Chicago W i t h t h e rapid g r o w t h of f r e e s t a n d i n g e m e r g e n c y c e n t e r s (FEes), there is some controversy regarding the severity of illness seen at these centers. This review examines p a t i e n t s referred from a network of 8 FEeS to a hospital ED. During the study, 17,387 p a t i e n t s were initially seen at the FEes, of w h o m 104 i0.6%) were transferred to hospitals for further evaluation. Sixtythree p a t i e n t s were referred to our base hospital, of w h o m 28 (44%) were admitted and 6 (9.5%) were admitted to critical care units. This compares to a 25% overall admission and 5% critical care admission rate from all ED visits. Four of the 6 critical care admissions arrived by ambulance, of w h o m 1 was unstable and required i m m e d i a t e cardioversion. The other 2 were n o t stabilized and arrived by private transport. With telephone followup, none of the patients discharged directly from the ED who were contacted had a missed diagnosis. According to telephone follow-up, 66% of the discharged patients were satisfied with FEC care and 100% were satisfied w i t h hospital care. Of the admitted patients, 87% were satisfied w i t h FEe t r e a t m e n t and 100% were satisfied w i t h hospital treatment. For a similar illness in the future, 29% of all patients would return to an FEC, 29% would return to a private practitioner, and 42% would go directly to a hospital. It appears that FEC referrals have a high hospitalization rate, and these patients were satisfied w i t h their care. Their future behavior would be changed so that less than one-third of these patients Would return to the FEe for a similar illness.
04
Is the Flight Physician Needed for Helicopter EMS?
KJ Rhee, M Strozeski, RE Burney, JR Mackenzie, K LaGrecaReibling / Section of Emergency Services, Department of Surgery, University of Michigan, Ann Arbor Despite the a c c u m u l a t i o n of years of experience w i t h helicopter emergency medical services for transport of critically ill and injured patients, the question of w h e t h e r physicians are needed in flight r e m a i n s an unresolved issue of major importance. We eXamined the costs and benefits of using flight physicians in one active HEMS program. During a study period of 4 months, all physician-specific contributions to medical care were recorded by means of a questionnaire that both flight physician and nurse filled out after eac h flight. With the questionnaire as a guide, the flight nurse was then interviewed in detail by one of the authors, with particular attention to whether the flight nurse could have substituted for the physician and w h e t h e r the physician's c o n t r i b u t i o n of skill or j u d g m e n t clearly led to an ira-
Annals of Emergency Medicine
517/197
ABSTRACTS
proved or potentially improved outcome for the patient. The flight physician was found to have made an impOrtant or unique contribution to the care of the patient in 38 of 174 flights (22%) completed during the period of study. Judgment was the most common contribution, cited on 29 flights (17%). Both skill and judgment were contributed on 7 additional flights (4%), and skill alone on only 2 flights (1%). Judgment was most frequently exercised in making diagnoses, initiating critical medical treatments, and determining destination. The cost to this program of providing physicians is approximately $85,000 per year, or 7% of an annual budget of approximately $1.2 million. Flight physicians make a substantial and important contribution tO patient care in HEMS operations, exercising critical judgment with regard to diagnosis, medical treatment, and disposition in 22% of transports. The benefits of this contribution far outweigh the 7% program cost.
1 0 5
Transconjunctival Oxygen Monitoring as a Predictor of Hypoxemia During Helicopter Transport
C Shufflebarger, D Jehle, E Cottington, M Martin / Division of Emergency Medicine, Allegheny General Hospital, Pittsburgh As the use of helicopters for air transport of critically ill patients increases, the availability of devices to monitor physiological parameters during flight becomes more important. It has long been known that arterial PO2 (PaO2) decreases during Unsupplemented, nonpressurized flight. In this study we examined the use of the transconjunctival oxygen (cjO2) monitor for assessing adequacy of arterial oxygenation during helicopter flight in 4 healthy volunteers. We compared arterial PaO2 as measured by conventional arterial blood gas analysis with cjOz at ground level, 5,000 feet, and 10,000 feet altitude. Mean PaOz dropped significantly from 93.5 to 81.5 to 58.5 tort, respectively (P < .001, analysis of variance with repeated measures). Mean cjO2 also decreased significantly from 63.8 to 52.0 to 34,8 torr, respectively (P < .001, analysis of variance with repeated measures). Within individual subjects, cjOz was an accurate predictor of PaOz (P < .001, multiple regression analysis). The relationship between cjO2 and PaO2 was linear with a regression coefficient of 1.147. We conclude that the transconjunctival Oa monitor may be useful for monitoring adequacy of arterial oxygenation during helicopter flight in hemodynamically stable patients. This study also supports the use of Supplemental oxygen in all patients subjected to helicopter transport.
1 0 6 Transports ""'"'Aeromedical Interhospital of Category I Motor-Vehicle. Related Trauma" Causes for Delays and Recommendations MJ Leicht, DJ Dula, TE Anderson, HW Gessner, GA Parrish, WD Rose, S Brotman / Departments of Emergency Medicine and Trauma Surgery, Geisinger Medical Center, Danville, Pennsylvania There are 65 million injuries annually in the United States, and trauma is the leading cause of death in the 1-40 age group. There were 42,584 motor-vehicle-related deaths in the US in 1983. Seventy percent of all trauma fatalities occur in rural areas, and the fatality rate for rural victims of auto accidents is 40% to 60% greater than for urban victims with comparable injuries. The time between occurrence of injury and start of appropriate therapy often becomes the factor determining survival. Adequate rural medical facilities are often so far from the scene of lifethreatening injury that recovery is unlikely. Our rural hospitalbased helicopter program staffed by emergency medicine physicians and flight nurses addresses the 5% of trauma victims in our area requiring tertiary care intervention by a trauma center. Inadequate hospital preparation of major trauma victims requiring aeromedical evacuation, however, often results in delays and increased ground time at the referring facility. We retrospectively
198/518
reviewed 126 consecutive category 1 motor-vehicle-related trauma victims transported by Life Flight helicopter from 25 hospitals to a regional trauma center in rural Pennsylvania during a 14month period. Overall mortality was 13%. Average round trip distance was 79 air miles. Ground times at the referring facility were taken from the dispatch log in a dedicated communications center. Procedures carried out by the flight team were taken from physician and nursing notes. Ground time at the referring facility from landing to liftoff averaged 42.0 minutes overall. Ground time when no interventions were required by the flight team averaged 31.2 minutes (baseline). However, 42 patients (33%) required major therapeutic interventions (principally airway management). This group averaged 57.4 minutes ground time, an 84% increase over baseline (P < .01). Care given by the flight teams and subsequent delays are summarized. Recommendations for ED preparation of motor-vehicle-related trauma victims requiring aeromedical evacuation are established.
107
Prehospitai Index: A Scoring System for Field Triage of Trauma Victims
JJ Koehler, MS Meindertsma, LJ Baer / Department of Emergency
Medicine, Butterworth Hospital, Grand Rapids; Section of Emergency Medicine, Department of Medicine, Michigan State University, College of Human Medicine, East Lansing The Pre-Hospital Index (PI) is a triage-oriented trauma severity scoring system comprised of 4 components: systolic BP, pulse, respiratory status, and level of consciousness. Each component has a scoring range of 0-5, with a resultant total range of 0-20. These 4 components were chosen and weighted after careful analysis of 313 consecutive trauma cases. The PI was developed to provide an objective prehospital scoring system for identifying those patients likely to die within 72 hours or require general or neurosurgical operative intervention within 36 hours (major trauma). Using these criteria, it was found that a PI of 0-3 indicated minor trauma, while a PI of 4-20 signified major trauma (penetrating abdominal or chest injuries are automatically classified as major trauma). Retrospective analysis of 465 consecutive tram ma cases revealed that patients with a PI of 0-3 (minor trauma) had a 0% mortality and a 2% rate of general or neurosurgical operative intervention. Those with a PI of 4-20 (major trauma) carried a 16.4% mortality and an emergent operate rate of 37.1%. The PI was then prospectively applied to 388 consecutive trauma cases presenting to the ED from October - December, 1984. Of the 353 patients scored as minor trauma in the field, there was a 0% mortality and only a 0.28% operative rate. Those scored as major trauma in the field had a mortality of 27% (PI 4-7, 0%; 8-20, 53%) and an operative rate of 40.5% (PI 4-7, 22%; 8-20, 57.9%). These data demonstrate the PI's ability to predict mortality (P < .001) and the need for emergent general or neurosurgical operative intervention (P < .001). The PI compares favorably in both s i m p l i c i t y and s t a t i s t i c a l r e l i a b i l i t y w i t h previously published trauma severity scoring systems such as the Trauma Index, Triage Index, Trauma Score, and the CRAMS Scale. Of these only the CRAMS Scale has been prospectively field tested. Testing of trauma severity indices in the context of their intended use is critical in determining their feasibility, accuracy, and ultimate utility. The PI has been found to be an easily implemented and statistically significant prehospital indicator of trauma severity.
108
Trauma Score Simplified
DR Kamens / Department of Emergency Medicine, University
Hospital of Jacksonville, Jacksonville, Florida Trauma severity scales, exemplified by the trauma score system (CTS) developed by Champion and coworkers, have encouraged quantification of injury severity in early trauma care. To assure rapid, accurate, and reproducible field assessment, it is es-
Annals of EmergencyMedicine
14:5 May 1985