The core content of emergency medical services medicine.

On September 23, 2010, the American Board of Medical Specialties (ABMS) approved emergency medical services (EMS) as a subspecialty of emergency medicine. As a result, the American Board of Emergency Medicine (ABEM) is planning to award the first certificates in EMS medicine in the fall of 2013. The purpose of subspecialty certification in EMS, as defined by ABEM, is to standardize physician training and qualifications for EMS practice, to improve patient safety and enhance the quality of emergency medical care provided to patients in the prehospital environment, and to facilitate integration of prehospital patient treatment into the continuum of patient care. In February 2011, ABEM established the EMS Examination Task Force to develop the Core Content of EMS Medicine (Core Content) that would be used to define the subspecialty and from which questions would be written for the examinations, to develop a blueprint for the examinations, and to develop a bank of test questions for use on the examinations. The Core Content defines the training parameters, resources, and knowledge of the treatment of prehospital patients necessary to practice EMS medicine. Additionally, it is intended to inform fellowship directors and candidates for certification of the full range of content that might appear on the examinations. This article describes the development of the Core Content and presents the Core Content in its entirety.

A case of unrecognized prehospital anaphylactic shock.

Abstract A case of prehospital anaphylactic shock that presented atypically, without a known exposure, is discussed. Anaphylaxis is a potentially life-threatening allergic reaction that requires prompt recognition and aggressive treatment. While there is little diagnostic dilemma (specifically used in the conclusion section of this paper) in the recognition and management of "classic" presentations of anaphylaxis there is likely a need for further education of prehospital providers, as well as emergency physicians, on how to recognize atypical cases of anaphylaxis. These cases can be equally severe, with potentially fatal consequences if missed. The diagnosis and management of anaphylaxis are reviewed, as well as barriers that providers encounter in diagnosing uncommon presentations.

Improved patient survival using a modified resuscitation protocol for out-of-hospital cardiac arrest.

BACKGROUND: Cardiac arrest continues to have poor survival in the United States. Recent studies have questioned current practice in resuscitation. Our emergency medical services system made significant changes to the adult cardiac arrest resuscitation protocol, including minimizing chest compression interruptions, increasing the ratio of compressions to ventilation, deemphasizing or delaying intubation, and advocating chest compressions before initial countershock. METHODS AND RESULTS: This retrospective observational cohort study reviewed all adult primary ventricular fibrillation and pulseless ventricular tachycardia cardiac arrests 36 months before and 12 months after the protocol change. Primary outcome was survival to discharge; secondary outcomes were return of spontaneous circulation and cerebral performance category. Survival of out-of-hospital arrest of presumed primary cardiac origin improved from 7.5% (82 of 1097) in the historical cohort to 13.9% (47 of 339) in the revised protocol cohort (odds ratio, 1.80; 95% confidence interval, 1.19 to 2.70). Similar increases in return of spontaneous circulation were achieved for the subset of witnessed cardiac arrest patients with initial rhythm of ventricular fibrillation from 37.8% (54 of 143) to 59.6% (34 of 57) (odds ratio, 2.44; 95% confidence interval, 1.24 to 4.80). Survival to hospital discharge also improved from an unadjusted survival rate of 22.4% (32 of 143) to 43.9% (25 of 57) (odds ratio, 2.71; 95% confidence interval, 1.34 to 1.59) with the protocol. Of the 25 survivors, 88% (n=22) had favorable cerebral performance categories on discharge. CONCLUSIONS: The changes to our prehospital protocol for adult cardiac arrest that optimized chest compressions and reduced disruptions increased the return of spontaneous circulation and survival to discharge in our patient population. These changes should be further evaluated for improving survival of out-of-hospital cardiac arrest patients.

The association of dispatch prioritization and patient acuity.

INTRODUCTION: EMS systems use call prioritization to distinguish between high and low acuity patients, better use resources, and set system response times. Previous research focused on patient condition; however, recent research has reviewed patient acuity as an important maker for system response. Our objective was to analyze any trend between priority dispatch determinant codes and using a red lights and siren (RLS) transport from the scene. METHODS: Retrospective cohort observational study of 9-1-1 calls received in CY 2003. Chi-square analysis for trend and odds ratios with 95% CI were calculated to evaluate the differences in proportions of patients being transported RLS from the scene according to determinant level, p < 0.05 was considered significant. RESULTS: There was significant heterogeneity among the determinant cohorts (chi-square = 204.477, p < 0.001, 5 df). Further analysis showed absolute and proportional increases in RLS transport from the scene with increasing determinant level. The three lowest determinant levels were low risk (OR 0.13, 0.49, and 0.58), and the two highest determinant levels had significant risk for RLS transport (OR 1.63, 32.11). CONCLUSIONS: Patients had increasing likelihood of being transported by RLS from the scene with increasing determinant level. Calls with the two highest determinant levels were at significant risk of being transported RLS from the scene.

The accuracy of predicting cardiac arrest by emergency medical services dispatchers: the calling party effect.

OBJECTIVES: To analyze the accuracy of paramedic emergency medical services (EMS) dispatchers in predicting cardiac arrest and to assess the effect of the caller party on dispatcher accuracy in an advanced life support, public utility model EMS system, with greater than 90,000 calls and greater than 60,000 transports per year. METHODS: This was a retrospective analysis from January 1, 2000, through June 30, 2000, of 911 calls with dispatcher-assigned presumptive patient condition (PPC) or field diagnosis of cardiac arrest. Sensitivity and positive predictive value (PPV) of the PPC code for cardiac arrest by calling parties were calculated. Homogeneity of sensitivity and PPV of the PPC code for cardiac arrest by calling parties was studied with chi-square analysis. Relevant proportions, relative risk ratios, and associated 95% confidence intervals (95% CIs) were calculated. Student's t-test was used to compare quality assurance scores between calling parties. RESULTS: There were 506 patients included in the study. Overall sensitivity for dispatcher-assigned PPC of cardiac arrest was 68.3% (95% CI = 63.3% to 73.0%) with a PPV of 65.0% (95% CI = 60.0% to 69.7%). There was a significant difference in the PPV for the EMS dispatcher diagnosis of cardiac arrest depending on the type of caller (chi(2) = 17.34, p < 0.001). CONCLUSIONS: A higher level of medical training may improve dispatch accuracy for predicting cardiac arrest. The type of calling party influenced the PPV of dispatcher-assigned condition.

Effect of paramedic experience on orotracheal intubation success rates.

This study's objective was to determine the effect of paramedic experience on orotracheal intubation success in prehospital adult nontraumatic cardiac arrest patients. This retrospective study analyzed all attempted intubations of prehospital adult nontraumatic cardiac arrest patients between January 1, 1997 and April 30, 1997 in an urban, all ALS service. Data were abstracted from EMS reports and intubation data forms. Variables included months of experience, number of patients in whom intubation was attempted, number of intubation attempts, success per attempt, and success per patient. Ninety-eight paramedics performed 909 intubations on 1066 cardiac arrest patients, yielding an intubation success rate of 85.3%. The median months of experience was 59.5 (Range 5-223). The median number of patients in whom intubation was attempted per paramedic was 10 (Range 1-36). The mean intubation success rate per paramedic was 80.6% (+/- 22.4, 95% CI 76.1, 85.1). There was significant correlation between total number of patients in whom intubation was attempted and intubation success rate (p <.001, R = 0.32). There was no correlation between months of experience and intubation success rate. In conclusion, the number of patients in whom intubation was attempted per paramedic was significantly correlated with the intubation success rate. Months of experience per paramedic had no significant correlation with intubation success rate.

Pediatric out-of-hospital emergency medical services utilization in Kansas City, Missouri.

OBJECTIVES: The objective was to describe epidemiologic features and usage patterns of pediatric emergency medical services (EMS) transports in Kansas City, Missouri. METHODS: The study consisted of a retrospective analysis of transports from January 1, 2002, to December 31, 2004, for Kansas City, Missouri, residents younger than 15 years of age (excluding interfacility transports. Data included demographics, insurance, day and time of transport, patient zip code, chief complaint, and number of individual transports. Rates were calculated using intercensal estimates for the denominator. All rates were expressed as number of transports per 1,000 persons per year (PPY). RESULTS: A total of 5,717 pediatric transports occurred in the 3-year study period. Transport rates were 18 PPY for all users, 42 PPY for those <1 year old, 23 PPY for ages 1-4 years, 12 PPY for ages 5-9 years, and 14 PPY for ages 10-14 years. Infants <1 year were more likely than children aged 5-9 years to use EMS (relative risk [RR] = 3.7, 95% confidence interval [CI] = 3.4 to 4.0). Males were more likely than females to use EMS (RR = 1.2, 95% CI = 1.1 to 1.3). Most (64%) were insured by Medicaid. Transports peaked between 4 pm and 8 pm, and lowest usage was 4 am to 8 am (p < 0.001). Overall usage did not vary by weekday or season. Respiratory transports were more common in the fall and winter, while trauma transports were more common in the summer (p < 0.001). The most common diagnoses were trauma (27%), neurologic (19%), and respiratory (18%). Eleven percent of users accessed EMS more than once (26% of all transports). There was a significant inverse linear relationship between transport rate and median family income by zip code (r = -0.36, p < 0.001). CONCLUSIONS: Children in zip codes with lower incomes, infants, and males were more likely to use EMS. Factors related to these increased transport rates are unknown.

Environmental factors encountered during out-of-hospital intubation attempts.

OBJECTIVES: Emergency medical services (EMS) literature has studied paramedic performance with endotracheal intubation; however, there are few data describing environmental differences between out-of-hospital and in-hospital providers during intubation attempts. The purpose of this study was to describe the environmental factors encountered by paramedics. SETTING: Midwest, urban, public utility model, all-advanced life support (ALS) ambulance service with 85,000 calls and 55,000 transports per year. DESIGN: Prospective, observational study using a standardized data-collection tool completed on all adult cardiac arrest patients for whom intubation was attempted during the period from September 1, 2000, through September 1, 2004. Descriptive data including count and frequency statistics of environmental factors were calculated. RESULTS: There were 1,894 attempts on 1,396 patients during the study period; 236 (12.5%) attempts on 161 patients (11.5%) were removed from the analysis because of incomplete data, leaving 1,658 attempts on 1,235 patients. The intubation success rate was 85% (95% confidence interval [CI] 83, 97). Paramedics most frequently attempt intubation indoors (1,239, 75%), prefer to kneel at the patient's head (899, 54%), encounter significant scene distractions (340, 20%), have optimal lighting (1,271, 77%), but frequently have suboptimal space (655, 40%). Patients are most often supine (1,653, 99%). CONCLUSIONS: The out-of-hospital intubation environment is significantly different from that of in-hospital providers. Paramedics frequently have a poor physical operating environment and encounter significant distractions while trying to perform endotracheal intubation. Future studies should analyze the association of these factors with intubation success.

Populations at risk for intubation nonattempt and failure in the prehospital setting.

OBJECTIVES: Pediatric cardiac arrest patients and adult traumatic arrest patients are perceived as more difficult to endotracheally intubate than adult cardiac arrest patients. The study hypothesis was that these populations were at higher risk of endotracheal intubation failure compared with adult cardiac arrest patients and that paramedics would more frequently defer attempts to intubate these patients. METHODS: This was a retrospective, observational study analyzing oral endotracheal intubations on pediatric cardiac arrest, adult traumatic arrest, and adult cardiac arrest patients over 66 months. Homogeneity of intubation nonattempt and endotracheal intubation failure was studied with chi-square analysis. Relative risks (RRs) with 95% confidence intervals (CIs) were used to compare pediatric cardiac arrest with adult traumatic arrest with adult cardiac arrest nonattempt rates and endotracheal intubation failure rates. RESULTS: 2,669 oral endotracheal intubations were included. There was a significant difference in intubation nonattempts and intubation failure between the combined pediatric cardiac arrest and adult traumatic arrest groups and the adult cardiac arrest cohort (RR 7.24, 95% CI 5.73, 9.16 for nonattempt; RR = 2.33, 95% CI 1.93, 2.83 for intubation failure). Both groups individually showed significant risk for intubation nonattempt and endotracheal intubation failure compared with adult cardiac arrest, with the pediatric cohort at higher risk for failure and the adult traumatic arrest cohort at higher risk for nonattempt. CONCLUSIONS: There was significant risk of intubation nonattempt and intubation failure in the pediatric cardiac arrest and adult traumatic arrest cohorts compared with the adult cardiac arrest population, with the pediatric cohort being at particularly high risk for intubation failure and the adult traumatic arrest cohort at higher risk for nonattempt.

Prospective determination of medical necessity for ambulance transport by paramedics.

OBJECTIVE: It has been estimated that between 11% and 61% of ambulance transports to emergency departments are not medically necessary. This study's objective was to analyze paramedic ability to determine the medical necessity of ambulance transport to the emergency department. METHODS: Paramedics prospectively assessed adult patients transported to an emergency department during a six-week period. The setting was an urban, all advanced life support, public utility model emergency medical services (EMS) system with 58,000 transports per year. Paramedics determined medical necessity of patient transport based on the following five criteria: 1) need for out-of-hospital intervention; 2) need for expedient transport; 3) potential for self-harm; 4) severe pain; or 5) other. On arrival in the emergency department, the emergency physician made a blinded determination based on the same criteria. Kappa statistics were used to assess agreement. RESULTS: Data forms were completed on 825 of 1,420 (58%) patients transported. Emergency physicians determined 248 (30%) transports were not necessary, paramedics 236 (29%), with agreement in 76.2% (K=0.42) of cases. Paramedics undertriaged 92 patients (11%). Rates of agreement on the five criteria were: 1) 71.9% (K=0.43); 2) 77.7% (K=0.22); 3) 89.6% (K=0.40); 4) 89.6 (K=0.32); and 5) 82.2% (K=0.29). CONCLUSIONS: Paramedics and emergency physicians agreed that a significant percentage of patients did not require ambulance transport to the emergency department. Despite only moderate agreement regarding which patients needed transport, the undertriage rate was low.