David R. Eitel

The emergency severity index triage algorithm version 2 is reliable and valid.

OBJECTIVES Initial studies have shown improved reliability and validity of a new triage tool, the Emergency Severity Index (ESI), over conventional three-level scales at two university medical centers. After pilot implementation and validation, the ESI was revised to include pediatric and updated vital signs criteria. The goal of this study was to assess ESI version (v.) 2 reliability and validity at seven emergency departments (EDs) in three states. METHODS In part 1, interrater reliability was assessed using weighted kappa analysis of written training cases and postimplementation by a random sampling of actual patient triages. In part 2, validity was analyzed using a prospective cohort with stratified random sampling at each site. The ESI was compared with outcomes including resource consumption, inpatient admission, ED length of stay, and 60-day all-cause mortality. RESULTS Weighted kappa analysis of interrater reliability ranged from 0.70 to 0.80 for the written scenarios (n = 3289) and 0.69 to 0.87 for patient triages (n = 386). Outcomes for the validity cohort (n = 1042) included hospitalization rates by ESI triage level: level 1, 83%; 2, 67%; 3, 42%; 4, 8%; level 5, 4%. Sixty-day all-cause mortality by triage level was as follows: level 1, 25%; 2, 4%; 3, 2%; 4, 1%; and 5, 0%. CONCLUSIONS ESI v. 2 triage produced reliable, valid stratification of patients across seven sites. ESI triage should be evaluated as an ED casemix identification system for uniform data collection in the United States and compared with other major ED triage methods.

Assessment of inter-observer reliability of two five-level triage and acuity scales: a randomized controlled trial

INTRODUCTION The Emergency Severity Index (ESI) is an initial measure of patient assessment in the emergency department (ED). It rates patients based on acuity and predicted resource intensity from Level 1 (most ill) to Level 5 (least resource intensive). Already implemented and evaluated in several US hospitals, ESI has yet to be evaluated in a Canadian setting or compared with the five-level Canadian Emergency Department Triage and Acuity Scale (CTAS). OBJECTIVE To compare the inter-observer reliability of 2 five-level triage and acuity scales. METHODS Ten triage nurses, who had all been trained in the use of CTAS, from 4 urban, academic Canadian EDs were randomly assigned either to training in ESI version 3 (ESI v.3) or to refresher training in CTAS. They independently assigned triage scores to 200 emergency cases, unaware of the rating by the other nurses. RESULTS Number of years of nursing practice was the only significant demographic difference found between the 2 groups (p = 0.014). A quadratically weighted kappa to measure the inter-observer reliability of the CTAS group was 0.91 (0.90, 0.99) and not significantly different from that of the ESI group 0.89 (0.88, 0.99). An inter-test generalizability (G) study performed on the variance components derived from an analysis of variance (ANOVA) revealed G(5) = 0.90 (0.82, 0.99). CONCLUSIONS After 3 hours of training, experienced triage nurses were able to perform triage assessments using ESI v.3 with the same inter-observer reliability as those with experience and refresher training in using the CTAS.

An Analysis of Invasive Airway Management in a Suburban Emergency Medical Services System

INTRODUCTION Airway management is the most critical and potentially life-saving intervention performed by emergency medical service (EMS) providers. Invasive airway management often is required in non-cardiac-arrest patients who are combative or otherwise uncooperative. The success of prehospital invasive airway management in this patient population was evaluated. METHODS A retrospective review was undertaken of the records of all such patients requiring endotracheal intubation over a three-year period (1987-1989). The study population included 278 patients enrolled by five advanced life support (ALS) units serving a suburban population of 425,000. Field trip sheets were reviewed for diagnosis, intubation method and success, number of intubation attempts, provider experience, reasons for unsuccessful intubations, and complications. RESULTS A total of 394 invasive airway management attempts were performed on 278 patients. The overall successful intubation rate was 75% (41% orotracheal, 52% nasotracheal, 7% other or unknown). The most common diagnoses were COPD and pulmonary edema (30%) and trauma (24%). Experienced providers were successful on the first attempt in 57% of cases compared to 50% by inexperienced providers (p=.24). Multiple intubation attempts were required in 33% of the patients. There was no statistically significant difference in success rates between the orotracheal and nasotracheal methods (p=.51). The most common reason for unsuccessful intubation was altered level of consciousness. Complications occurred with 7% of successful attempts and in 18% of unsuccessful attempts (p less than .001). Forty-six percent of the patients who were not intubated successfully in the field and required intubation in the emergency department (ED) received a neuromuscular blocking agent prior to successful intubation. CONCLUSION Prehospital providers can intubate a high but improvable proportion of non-cardiac-arrested patients by both the orotracheal and nasotracheal routes. The use of pharmacologic adjuncts to facilitate the prehospital intubation of selected, non-cardiac-arrested patients is a promising adjunct that needs further evaluation.

Intraosseous infusion: Success of a standardized regional training program for prehospital advanced life support providers

STUDY OBJECTIVE To evaluate a standardized training program in intraosseous (IO) infusion for prehospital providers. DESIGN Prospective multicenter 24-month study. SETTING IO infusions were performed by prehospital providers from eight advanced life support units serving 14 hospitals within nine counties. PARTICIPANTS Field advanced life support providers (paramedics and registered nurses). INTERVENTIONS All providers participated in a one-hour standardized training session and supervised hands-on simulation. Providers completed a data sheet on all IO infusions performed. Data sheets were collected and summarized. RESULTS One hundred thirty-four prehospital providers completed the training session and were approved to perform the procedure. Fifteen patients requiring IO infusion were encountered during the study period. Thirteen (87%) had IO infusion completed successfully. Clinical indications included 11 patients in cardiac arrest, two trauma resuscitations, one seizure, and one toxic ingestion. Patient ages ranged from 1 to 24 months. Seven patients were initially resuscitated. Four survived to hospital discharge. Procedural complications included one incidence of local fluid extravasation and one IO line that became dislodged en route. There were no complications at time of discharge in the four survivors. All procedures were performed in less than two minutes. CONCLUSION A one-hour standardized training session was successfully used to train prehospital providers in the procedure of IO infusion. IO infusion then was implemented into their clinical practice with a satisfactory success rate and few complications.

One-year survival after prehospital cardiac arrest: The Utstein style applied to a rural-suburban system☆

To evaluate the recently published Utstein algorithm (Ann Emerg Med 1991;20:861), the authors conducted a retrospective review of all advanced life support (ALS) trip sheets and hospital records of patients with prehospital cardiac arrests between January 1988 and December 1989. Telephone follow-up was used to determine 1-year survival rates. Of 713 arrests in the 24-month study period, 601 were of presumed cardiac etiology. Approximately 599 of these charts were available for analysis. One hundred ninety-three (32.2%) of these had return of spontaneous circulation (ROSC), 36 (6.0%) survived to hospital discharge, and 24 were alive at 1-year follow-up (4.0% of total or 67% of survivors to discharge). The Utstein style was found to be a useful algorithmic format for reporting prehospital cardiac arrest data in a manner that should allow direct comparison between emergency medical service (EMS) systems. Existing prehospital record-keeping practices (trip sheets) are easily adapted to this style of data collection, although certain data for the template (eg, resuscitations not attempted and alive at 1-year) are more difficult to ascertain. Additionally, the authors report their own experience during a 2-year period, including data that suggest that the majority of patients with cardiac arrest who survive to hospital discharge are still alive at 1 year.

An evaluation of the esophageal detector device using a cadaver model

The study was conducted to evaluate the usefulness of an esophageal detector device (EDD) to correctly differentiate between esophageal and tracheal intubation. The study was conducted in the emergency department using 10 recently decreased cadavers (nine males, one female, age range 50-72 years). An 8-mm internal diameter endotracheal tube was placed orally into the trachea, and a second 8-mm ID tube was placed orally into the esophagus. Both tubes extended the same distance from the mouth, and the cuffs were not inflated. After placement of the tubes, the EDD was used by advanced life support providers (physicians, nurses, paramedics, and respiratory therapists) to determine if each tube was in the trachea or the esophagus. The persons who assessed the tube placement were not present when the tubes were placed into the cadavers. Multiple evaluators were allowed for each cadaver, but each evaluator only participated one time for each cadaver. The bulb of the EDD was squeezed by the evaluator, who then attached it to the endotracheal tube and rated the bulb inflation as immediate inflation, delayed inflation, or no inflation. Prior to participation in the study, evaluators were instructed in the use of the EDD. There were a total of 45 trials performed on the cadavers (median, four evaluations/cadaver, range, one-eight). For the tracheal tube, the EDD inflated immediately in all cases; it was thus 100% correct in identification of tracheal intubation. For the esophageal tube, the EDD did not inflate in 44 cases, and in one case it filled with vomitus; it thus correctly identified esophageal intubation in all cases.(ABSTRACT TRUNCATED AT 250 WORDS)

An evaluation of pulse oximetry in prehospital care

STUDY OBJECTIVES We performed this study to evaluate the accuracy of pulse oximetry oxygen saturation (SpO2) against direct measurements of arterial oxygen saturation (SaO2) in the field. DESIGN Prospective, cross-sectional, paired measurements of SpO2 against SaO2. SETTING This evaluation was done in the prehospital setting. INTERVENTIONS A pulse oximeter with digital probe was used to measure SpO2 in 30 patients. Arterial blood gases were drawn in the field while the pulse oximeter was in use, and oxygen saturation (HbO2) was measured by CO-oximetry. MAIN RESULTS There was no significant difference between SpO2 (94.6 +/- 5.4%) and HbO2 (94.9 +/- 5.1%) (P = .495, beta less than .2). There was a strong correlation between SpO2 and HbO2 (r = .898). The bias between SpO2 and HbO2 was -0.3, with a precision of 2.4. When SpO2 was 88% or more, HbO2 was 90% or more in every case. Mean carboxyhemoglobin was 1.3 +/- 0.9%, and mean methemoglobin was 0.9 +/- 0.3%. There was no significant difference between the pulse oximeter heart rate and the ECG heart rate (P = .223, beta less than .2). CONCLUSION We conclude that pulse oximetry is sufficiently accurate to be useful in the field when SpO2 is more than 88%. It is potentially useful in patients with clinical signs of acute hypoxemia and in patients receiving interventions that may produce acute hypoxemia. Further work is needed to evaluate the accuracy of pulse oximetry in the settings of elevated carboxyhemoglobin, methemoglobin, and very low saturations.

Noninvasive transcutaneous cardiac pacing in prehospital cardiac arrest

This study evaluated the efficacy of prehospital external cardiac pacing in cardiac arrest patients. From October 1984 to June 1985, 91 patients were paced. Mean time from cardiac arrest to advanced life support (ALS) intervention in this metropolitan-rural ALS system was 14.5 minutes. Electrical capture occurred in 85 (93%), mechanical capture (pulses) occurred in ten (11%), and a measurable blood pressure occurred in three (3%) of the 91 patients. Despite a high rate of electrical capture, palpable pulses were produced only in 11%, and no patients survived to be discharged from the hospital. There was no difference in the frequency of electrical capture, palpable pulses, or outcome for patients receiving pharmacologic intervention before or after pacing. Likewise there was no difference in the frequency of electrical capture, palpable pulses, or outcome for patients receiving ALS therapy within or after ten minutes of their arrest. Although we found that external cardiac pacing was easily used in the prehospital setting, pacing did not result in any increase in survival in cardiac arrest patients.

Prehospital administration of inhaled metaproterenol

STUDY OBJECTIVES We conducted a study of the prehospital use of inhaled metaproterenol. DESIGN, SETTING, TYPE OF PARTICIPANTS, AND INTERVENTIONS: Advanced life support (ALS) providers were trained with a standardized curriculum to identify patients likely to benefit from prehospital inhaled metaproterenol administration. Unit doses of metaproterenol were used in a small-volume nebulizer. We prospectively included 122 patients in an initial study (71 men; age, 63 +/- 19 years) to evaluate the safety and effectiveness of metaproterenol in the field, and 150 patients (including the original 122) in an additional study to evaluate patient selection criteria. MEASUREMENTS AND MAIN RESULTS The treatments resulted in an increase in peak flows, a decrease in respiratory rates, and no change in heart rates. In 62% of patients, the increase in peak flow exceeded 15%. Wheezing improved in 59% of the patients, worsened in 4%, and did not change in the remainder. Air entry by auscultation improved subjectively in 59% of patients. Mild tremor occurred in 8% of patients, moderate tremor occurred in 1%, and no tremor occurred in the remainder. Significant dysrhythmias did not occur. CONCLUSIONS ALS providers correctly identified patients for this therapy. No technical problems were encountered in the field with this treatment approach. We conclude that ALS providers can be taught to identify patients likely to benefit from inhaled metaproterenol, that inhaled metaproterenol can be administered in the field, and that metaproterenol is both safe and effective when used in the prehospital setting.

Prehospital use of a prototype esophageal detection device: a word of caution!

OBJECTIVE To determine the effectiveness of a prototype esophageal detection device (EDD) during use in the prehospital setting. DESIGN/SETTING Prospective convenience sample in a prehospital setting. POPULATION Intubated adult patients. INTERVENTIONS The study device was used to determine esophageal or endotracheal placement of endotracheal tubes in intubated patients. Clinical means were used to confirm tube location. A data sheet was completed for each patient. RESULTS Of 105 uses of the device, 17 of 17 esophageal tubes were identified correctly (100% sensitivity). Sixty-five of 88 tracheal tubes were correctly identified (78% specificity). There was intermediate reinflation of the device on 13 of the 65 tracheal tubes. Five tests were indeterminate. There were no false negatives (negative predictive value 100%), but 18 false positives (positive predictive value 48%). CONCLUSION This prototype EDD adequately identifies esophageally placed endotracheal tubes. Correct identification of endotracheally placed tubes was less sensitive. Much work needs to be done regarding the use of negative aspiration devices to identify placement of endotracheal tubes.