Baxter Larmon

Spinal immobilization on a flat backboard: Does it result in neutral position of the cervical spine?

STUDY OBJECTIVES To determine the amount of occipital padding required to achieve neutral position of the cervical spine when a patient is immobilized on a flat backboard. Neutral position was defined as the normal anatomic position of the head and torso that one assumes when standing looking straight ahead. DESIGN Descriptive with hypothesis testing of selected descriptive elements. SETTING University campus and hospital. SUBJECTS One hundred healthy young adults with no history of back disease. INTERVENTIONS Volunteers were measured in standing and supine positions. MEASUREMENTS Occipital offset; height; weight; and head, neck, and chest circumferences were measured for each subject. MAIN RESULTS The amount of occipital offset required to achieve neutral position varied from 0 to 3.75 in. (mean, 1.5 in.). Mean occipital offset for men (1.67 in.) was significantly greater than that for women (1.31 in.) Easily obtained body measurements did not accurately predict occipital offset. CONCLUSION Immobilization on a flat backboard would place 98% of our study subjects in relative cervical extension. Occipital padding would place a greater percentage of patients in neutral position and increase patient comfort during transport.

EMS Management of Acute Stroke—Prehospital Triage (Resource Document to NAEMSP Position Statement)

PREHOSPITAL EMERGENCY CARE 2007;11:313–317

Differential front and back seat safety belt use by prehospital care providers

The object of the study was to assess the habits and attitudes of prehospital care personnel regarding safety belt use in the front and rear ambulance compartments. Therefore, a cross-sectional descriptive survey was administered at emergency medical service conferences and through provider agencies throughout the United States and Canada. Approximately 900 public, private, and volunteer prehospital care providers participated. Demographic information, traffic collision history, percent of time safety belts were used, belief in safety belt use, and reasons for nonuse in the rear compartment of the ambulance were measured. The results showed that safety belt use was highest in the front seat during emergency runs (median, 100%) and rarest in the back compartment during emergency runs (median, 0%). Respondents cited the following reasons for non-use in the rear compartment: inhibited patient care (67.9%), restricted movement (34.7%) inconvenience (15.1%), or lack of efficacy (5.3%). Prehospital care personnel typically wear safety belts when in the front seat, but not while in the rear compartment of the ambulance. More intensive efforts at educating prehospital care providers about the importance of safety restraints in the rear compartment, enumerating patient care activities that can be performed while wearing a safety belt, and design of a functional restraint system for the rear compartment may increase ambulance safety.

Are EMS call volume predictions based on demand pattern analysis accurate

Most EMS systems determine the number of crews they will deploy in their communities andwhen those crews will be scheduled based on anticipated call volumes. Many systems use historical data to calculate their anticipated call volumes, a method of prediction known as demand pattern analysis. Objective. To evaluate the accuracy of call volume predictions calculated using demand pattern analysis. Methods. Seven EMS systems provided 73 consecutive weeks of hourly call volume data. The first 20 weeks of data were used to calculate three common demand pattern analysis constructs for call volume prediction: average peak demand (AP), smoothed average peak demand (SAP), and90th percentile rank (90%R). The 21st week served as a buffer. Actual call volumes in the last 52 weeks were then compared to the predicted call volumes by using descriptive statistics. Results. There were 61,152 hourly observations in the test period. All three constructs accurately predicted peaks andtroughs in call volume but not exact call volume. Predictions were accurate (±1 call) 13% of the time using AP, 10% using SAP, and19% using 90%R. Call volumes were overestimated 83% of the time using AP, 86% using SAP, and74% using 90%R. When call volumes were overestimated, predictions exceeded actual call volume by a median (Interquartile range) of 4 (2–6) calls for AP, 4 (2–6) for SAP, and3 (2–5) for 90%R. Call volumes were underestimated 4% of time using AP, 4% using SAP, and7% using 90%R predictions. When call volumes were underestimated, call volumes exceeded predictions by a median (Interquartile range; maximum under estimation) of 1 (1–2; 18) call for AP, 1 (1–2; 18) for SAP, and2 (1–3; 20) for 90%R. Results did not vary between systems. Conclusion. Generally, demand pattern analysis estimated or overestimated call volume, making it a reasonable predictor for ambulance staffing patterns. However, it did underestimate call volume between 4% and7% of the time. Communities need to determine if these rates of over-and underestimation are acceptable given their resources andlocal priorities.

Results of a 4-Hour Endotracheal Intubation Class for EMT-Basics

STUDY OBJECTIVE In 1994, the Department of Transportation made endotracheal intubation an optional EMT-Basic skill. To data, there have been no studies addressing the ability of this group to learn or perform this skill. We used a standarized mannequin test to perform a prospective evaluation of this intubation skills of basic EMTs immediately after a 4-hour course on endotracheal intubation. We hypothesized that the intubation success rates would be comparable with those of other types of providers newly trained in this skill. METHODS Eighty-three EMTS were selected/recruited from four EMS provider agencies. Ninety-six percent of the EMTs were men, and the average age was 38 years; average length of EMT experience was 9.4 years. Training was provided in classes of 6 to 14 persons and included 1 hour of didactic instruction, a 1-hour demonstration of intubation techniques, and 90 minutes of supervised practice with the mannequins in groups of 2 to 4 persons. Testing followed American Heart Association guidelines. Interrater reliability of test criteria was assessed. RESULTS Ninety-four percent (95% confidence interval 86% to 98%) of the EMTs passed the examination by intubating the mannequin within 35 seconds within 3 attempts. Of the successful EMTs, 94% succeeded on their first attempt, 3% on their second attempt, and 3% on their third. There were three esophageal intubations; all were detected immediately. Interrater agreement was 100% on the pass/fail decision. CONCLUSION This 4-hour class trained basic EMTs to perform endotracheal intubation on mannequins with a success rate of 94%. Further research should confirm the ability of EMT-Basics to detect esophageal intubation and address the retention of intubation skills, the applicability of these skills to the field, and the components of this course that were responsible for its success.

P REHOSPITAL C ARE R ESEARCH F ORUM /NAEMSE 2002

Introduction: While there is no substitute for observational evaluation of student clinical performance, it is inherently faulty for a variety of reasons, including errors of human perception. Perceptual bias has not, to date, received a great deal of attention in emergency medical services (EMS) clinical education. To maximize the reliability and validity of clinical performance evaluation, we must identify which common types of perceptual bias impact preceptor ratings of student performance. Hypothesis: The hypothesis of this study is that preceptors’ ratings of student performance demonstrate the “horns/halo” bias based on the preceptors’ ratings of the professionalism of student attire. (The horns/halo effect is a common term used in education to describe possible bias in evaluating student achievement.) Methods: Data were collected from 99 EMS lieutenants during a preceptor workshop. Participants were shown one of two videos, either a video of a simulated student dressed in typical EMS student attire (video B, n = 52) or a video in which the simulated student wore jeans, a tee shirt, and a cap (video A, n = 47). The scenario and student performance were held constant for both videos. Participants were instructed to rate student performance using the evaluation instrument distributed. Data were analyzed using a oneway between-subjects analysis of variance (ANOVA). Results: The mean score for professionalism, on a scale of 1 (lowest) to 4 (highest), for group B was 3.5, and for group A was 1.7 (p < 0.0001). The mean total performance score (all dimensions of performance excluding professionalism) on a scale of 8 to 32 for group B was 20.75, and for group A was 18.87 (p = 0.0214). The hypothesis that preceptors’ ratings of student performance demonstrate the effect of the horns/ halo bias based on the preceptors’ ratings of the professionalism of student attire was demonstrated in this study. Conclusions: The presence of bias due to perceptual errors affects the ratings of actual student performance. Since EMS educational programs depend upon the assessment of student performance by preceptors to determine student competency, educational programs must make preceptors aware of sources of perceptual biases and emphasize the independent and objective rating of individual dimensions of student performance.