Vehicle-at-scene-to-patient-access interval measured with computer-aided dispatch.

STUDY OBJECTIVE: To determine whether the vehicle-at-scene-to-patient-access (VSPA) interval could be measured by means of crew reporting to a computer-aided dispatch operation. DESIGN: A prospective demonstration-proof-methodology pilot study using crew reporting of access time on emergency calls. SETTING: An urban, public utility model (a type of EMS system), all-ALS system. PARTICIPANTS: Six ambulance crews (four day and two night). INTERVENTIONS: Times were collected by radio reporting. A survey was to be completed for each call. RESULTS: Two hundred ninety-two calls met study criteria; 181 had corresponding surveys. Crew reporting compliance ranged from 52.8% to 94%. Poor radio transmission was cited infrequently as a reason for noncompliance. The median VSPA interval for all calls was 1.3 minutes (interquartile range, .8 to 2.6 minutes). Twenty-five percent of calls had intervals of more than 2.5 minutes, and 10% had an interval of more than 5 minutes. CONCLUSION: Our study suggests that it is feasible for ambulance crews to report patient access times. Methods to improve the consistency and frequency of crew reporting should be considered. The VSPA access interval varies in length and is not normally distributed.

System implications of the ambulance arrival-to-patient contact interval on response interval compliance.

BACKGROUND: In some emergency medical services (EMS) system designs, response time intervals are mandated with monetary penalties for noncompliance. These times are set with the goal of providing rapid, definitive patient care. The time interval of vehicle at scene-to-patient access (VSPA) has been measured, but its effect on response time interval compliance has not been determined. PURPOSE: To determine the effect of the VSPA interval on the mandated code 1 (< 9 min) and code 2 (< 13 min) response time interval compliance in an urban, public-utility model system. METHODS: A prospective, observational study used independent third-party riders to collect the VSPA interval for emergency life-threatening (code 1) and emergency nonlife-threatening (code 2) calls. The VSPA interval was added to the 9-1-1 call-to-dispatch and vehicle dispatch-to-scene intervals to determine the total time interval from call received until paramedic access to the patient (9-1-1 call-to-patient access). Compliance with the mandated response time intervals was determined using the traditional time intervals (9-1-1 call-to-scene) plus the VSPA time intervals (9-1-1 call-to-patient access). Chi-square was used to determine statistical significance. RESULTS: Of the 216 observed calls, 198 were matched to the traditional time intervals. Sixty-three were code 1, and 135 were code 2. Of the code 1 calls, 90.5% were compliant using 9-1-1 call-to-scene intervals dropping to 63.5% using 9-1-1 call-to-patient access intervals (p < 0.0005). Of the code 2 calls, 94.1% were compliant using 9-1-1 call-to-scene intervals. Compliance decreased to 83.7% using 9-1-1 call-to-patient access intervals (p = 0.012). CONCLUSION: The addition of the VSPA interval to the traditional time intervals impacts system response time compliance. Using 9-1-1 call-to-scene compliance as a basis for measuring system performance underestimates the time for the delivery of definitive care. This must be considered when response time interval compliances are defined.

Ambulance arrival to patient contact: the hidden component of prehospital response time intervals.

STUDY OBJECTIVE: To determine the time between ambulance arrival at the scene to paramedic arrival at the patient (arrival to patient contact) and the effect of barriers to paramedic movement on this time interval. DESIGN: A prospective, observational study. Time intervals were collected by independent third-party riders on emergency (Code 1 and Code 2) calls. Potential barriers to paramedic movement were recorded. SETTING: Public utility model urban emergency medical services system. TYPE OF PARTICIPANTS: Two hundred thirty-two emergency ambulance calls were observed, and data were analyzed from 216. INTERVENTIONS: None. RESULTS: The median arrival-to-patient contact interval for all calls was 1.33 minutes (interquartile range, 0.67 to 4.13 minutes). Barriers prolonged the arrival-to-patient contact interval (P < .001, Kolmogorov-Smirnov test). The median arrival-to-patient contact interval was 2.29 minutes (1.01 to 4.82 minutes) for 122 runs with barriers and 0.82 minutes (0.37 to 1.96 minutes) for 94 runs without barriers. CONCLUSION: The arrival-to-patient contact interval adds a variable and potentially lengthy amount of time to the total prehospital response time interval, and barriers impeding paramedic movement to the patient prolong this time interval. In 25% of all observed paramedic calls, the arrival-to-patient contact interval was more than four minutes. Measurement of the time from ambulance arrival on the scene to paramedic arrival at the patient is necessary to appropriately determine the relationship among total prehospital response time, paramedic interventions, and patient outcome.

Emergency department interpretation of electrocardiograms.

STUDY OBJECTIVE: To determine the concordance of emergency physicians' and cardiologists' interpretations of abnormal ECGs. DESIGN: Retrospective cohort study. SETTING: An urban teaching hospital emergency department. TYPE OF PARTICIPANTS: Patients with an abnormal ED ECG that was interpreted by both an emergency physician and a cardiologist and who were discharged from the ED. MEASUREMENTS AND MAIN RESULTS: Seven hundred sixteen ECGs were reviewed; 143 abnormal ECGs were obtained on patients discharged from the ED. The cardiologist's final interpretation was defined as correct, and discordance was any abnormality not identified by the emergency physician. The overall discordance between emergency physicians' and cardiologists' ECG interpretations was 58.0% (P less than .001). Twenty-five discordant interpretations were likely clinically significant--representing missed ischemia, infarct, and abnormal rhythm. There was no ED interpretation in three of these. The most frequently missed findings by emergency physicians were evidence of ischemia/infarct of the anterior wall and atrial fibrillation. Twenty-one of the 83 patients with discordant interpretations were lost to follow-up. Two cases had a clinically significant discrepancy that would have altered patient care. CONCLUSION: Although the overall discordance was more than 50%, most ED misinterpretations were determined unlikely to have clinical significance. Additional studies are needed to identify variables that contribute to ED ECG misinterpretation and to develop methods to resolve these difficulties.

Effect of standing orders on paramedic scene time for trauma patients.

STUDY OBJECTIVE: To determine if a protocol change that allowed paramedics to perform certain procedures before base station contact (standing orders) would decrease scene time in trauma patients. DESIGN: Retrospective review of case series. SETTING: A single-tiered, all advanced life support emergency medical services system. INTERVENTION: Implementation with standing orders for invasive procedures. TYPE OF PARTICIPANTS: All physiologically unstable trauma patients transported to a Level I trauma center by ambulance. MEASUREMENTS AND MAIN RESULTS: One hundred ninety-seven patients met the inclusion criteria--87 before and 110 after the initiation of standing orders. Mean scene times for the control group (15.3 +/- 8.4 minutes) and for the standing orders group (15.1 +/- 7.6 minutes) were similar (P = .18). The power of the study to detect a two-minute difference in scene time was .92. Scene time was not influenced by mechanism of injury, and the number of procedures performed on patients was similar between the two groups. CONCLUSION: Standing orders did not decrease scene time in physiologically unstable trauma patients. Further study is necessary to delineate the factors that actually contribute to on-scene time and the factors that are important in determining whether standing orders or on-line medical contact should be used.

Clinically significant radiograph misinterpretations at an emergency medicine residency program.

Radiographic misinterpretation rates have been suggested as a quality assurance tool for assessing emergency departments and individual physicians, but have not been defined for emergency medicine residency programs. A study was conducted to define misinterpretation rates for an emergency medicine residency program, compare misinterpretation rates among various radiographic studies, and determine differences with respect to level of training. A total of 12,395 radiographic studies interpreted by emergency physicians during a consecutive 12-month period were entered into a computerized data base as part of our quality assurance program. The radiologist's interpretation was defined as correct. Clinical significance of all discrepancies was determined prospectively by ED faculty. Four hundred seventy-five (3.4%) total errors and 350 (2.8%) clinically significant errors were found. There was a difference in clinically significant misinterpretation rates among the seven most frequently obtained radiograph studies (P less than .0005, chi 2), accounted for by the 9% misinterpretation rates for facial films. No difference (P = .421) was noted among full-time, part-time, third-year, second-year, and "other" physicians. This finding is likely due to faculty review of residents' readings. Evaluation of misinterpretation rates as a quality assurance tool is necessary to determine the role of radiographic quality assurance in emergency medicine resident training. Educational activities should be directed toward radiographic studies with higher-than-average reported misinterpretation rates.