Triage By Emergency Medical Dispatchers

Advancing access to care: An assessment of the prehospital system in Senegal

BACKGROUND

Most low- and middle-income countries do not have a mature prehospital system limiting access to definitive care. This study sought to describe the current state of the prehospital system in Senegal and offer recommendations aimed at improving system capacity and population access to definitive care.

METHODS

Structured interviews were conducted with key informants in various regions throughout the country using qualitative and quantitative techniques. A standardized questionnaire was generated using needs assessment forms and system frameworks. Descriptive statistics were performed for quantitative data analysis, and qualitative data was consolidated and presented using ATLAS.ti.

RESULTS

Two (20%) of the studied regions, Dakar and Saint-Louis, had a mature prehospital system in place, including dispatch centers and teams of trained personnel utilizing equipped ambulances. 80% of the studied regions lacked an established prehospital system. The vast majority of the population relied on the fire department for transport to a healthcare facility. The ambulances in rural regions were not part of a formal prehospital system, were not equipped with life-support supplies, and were limited to inter-facility transfers.

CONCLUSIONS

While Dakar and Saint-Louis have mature prehospital systems, the rest of the country is served by the fire department. There are significant opportunities to further strengthen the prehospital system in rural Senegal by training the fire department in basic life support and first aid, maintaining cost efficiency, and building on existing national resources. This has the potential to significantly improve access to definitive care and outcomes of emergent illness in the Senegalese community.

Deep ensemble multitask classification of emergency medical call incidents combining multimodal data improves emergency medical dispatch

The objective of this work was to develop a predictive model to aid non-clinical dispatchers to classify emergency medical call incidents by their life-threatening level (yes/no), admissible response delay (undelayable, minutes, hours, days) and emergency system jurisdiction (emergency system/primary care) in real time. We used a total of 1 244 624 independent incidents from the Valencian emergency medical dispatch service in Spain, compiled in retrospective from 2009 to 2012, including clinical features, demographics, circumstantial factors and free text dispatcher observations. Based on them, we designed and developed DeepEMC², a deep ensemble multitask model integrating four subnetworks: three specialized to context, clinical and text data, respectively, and another to ensemble the former. The four subnetworks are composed in turn by multi-layer perceptron modules, bidirectional long short-term memory units and a bidirectional encoding representations from transformers module. DeepEMC² showed a macro F1-score of 0.759 in life-threatening classification, 0.576 in admissible response delay and 0.757 in emergency system jurisdiction. These results show a substantial performance increase of 12.5 %, 17.5 % and 5.1 %, respectively, with respect to the current in-house triage protocol of the Valencian emergency medical dispatch service. Besides, DeepEMC² significantly outperformed a set of baseline machine learning models, including naive bayes, logistic regression, random forest and gradient boosting (α = 0.05). Hence, DeepEMC² is able to: 1) capture information present in emergency medical calls not considered by the existing triage protocol, and 2) model complex data dependencies not feasible by the tested baseline models. Likewise, our results suggest that most of this unconsidered information is present in the free text dispatcher observations. To our knowledge, this study describes the first deep learning model undertaking emergency medical call incidents classification. Its adoption in medical dispatch centers would potentially improve emergency dispatch processes, resulting in a positive impact in patient wellbeing and health services sustainability.

Prevalence and risk factors of secondary traumatic stress in emergency call-takers and dispatchers - a cross-sectional study

Background: Emergency call-takers and dispatchers (ECDs) field emergency calls and dispatch the appropriate emergency services. Exposure to the callers' traumatic experiences can lead to psychological stress and even to secondary traumatic stress (STS). In addition, previous studies suggest that ECDs may also suffer from posttraumatic stress disorder (PTSD), depression and anxiety disorders. Objectives: To investigate the prevalence of STS and to screen for PTSD, depression and anxiety disorders in ECDs. We further aimed to identify sociodemographic variables and attachment styles as possible risk factors for higher STS symptom load in ECDs. Methods: STS and PTSD regarding lifetime traumatic events, as well as depression and anxiety disorders, were investigated in N = 71 ECDs. Multiple regression analysis was performed to identify possible risk factors for higher STS symptom load. Results: The analysis determined a prevalence of 8.5% for moderate STS and 2.8% for severe STS. A total of 11.3% of the ECDs screened positive for PTSD, 15.5% for depression and 7.0% for anxiety disorders. A higher number of children and the absence of a secure attachment style were identified to be significantly associated with higher STS symptom load. Conclusions: STS resulting from exposure to traumatic emergency caller content is a common phenomenon among ECDs. Specific sociodemographic variables and the attachment style are significant risk factors of STS symptom load. ECDs should receive regular psychoeducational interventions and supervision to identify and mitigate mental distress at an early stage.

Aeromedical evacuation of the trauma patient

Aeromedical evacuation of the trauma patient in the UK is uncommon but controversial. This article compares services in the UK with other, more developed services, particularly those in France and Germany. The important subject of despatch and control and the controversy over different crew configurations are considered. The available, often contradictory evidence for altered patient outcome is reviewed. As with many advances in the quality of medical care it appears that isolating the effect of aeromedical evacuation on the crude indicator of mortality is difficult. World-wide, aeromedical systems are here to stay, and it is up to individual governments and agencies to decide on the level of financial support and priority that they will receive.

Using On-scene EMS Responders' Assessment and Electronic Patient Care Records to Evaluate the Suitability of EMD-triaged, Low-acuity Calls for Secondary Nurse Triage in 911 Centers

INTRODUCTION

Using the Medical Priority Dispatch System (MPDS) - a systematic 911 triage process - to identify a large subset of low-acuity patients for secondary nurse triage in the 911 center is a largely unstudied practice in North America. This study examines the ALPHA-level subset of low-acuity patients in the MPDS to determine the suitability of these patients for secondary triage by evaluating vital signs and necessity of lights-and-siren transport, as determined by attending Emergency Medical Services (EMS) ambulance crews.

OBJECTIVES

The primary objective of this study was to determine the clinical status of MPDS ALPHA-level (low-acuity) patients, as determined by on-scene EMS crews' patient care records, in two US agencies. A secondary objective was to determine which ALPHA-level codes are suitable candidates for secondary triage by a trained Emergency Communication Nurse (ECN).

METHODS

In this retrospective study, one full year (2013) of both dispatch data and EMS patient records data, associated with all calls coded at the ALPHA-level (low-acuity) in the dispatch protocol, were collected. The primary outcome measure was the number and percentage of ALPHA-level codes categorized as low-acuity, moderate-acuity, high-acuity, and critical using four common vital signs to assign these categories: systolic blood pressure (SBP), pulse rate (PR), oxygen saturation (SpO2), and Glasgow Coma Score (GCS). Vital sign data were obtained from ambulance crew electronic patient care records (ePCRs). The secondary endpoint was the number and percentage of ALPHA-level codes that received a "hot" (lights-and-siren) transport.

RESULTS

Out of 19,300 cases, 16,763 (86.9%) were included in the final analysis, after excluding cases from health care providers and those with missing data. Of those, 89% of all cases did not have even one vital sign indicator of unstable patient status (high or critical vital sign). Of all cases, only 1.1% were transported lights-and-siren.

CONCLUSION

With the exception of the low-acuity, ALPHA-level seizure cases, the ALPHA-level patients are suitable to transfer for secondary triage in a best-practices, accredited, emergency medical dispatch center that utilizes the MPDS at very high compliance rates. The secondary nurse triage process should identify the few at-risk patients that exist in the low-acuity calls.

Reports and Session Summaries of the 17th World Congress on Disaster and Emergency Medicine

This section of Prehospital and Disaster Medicine (PDM) presents reports and summaries of the 17th World Congress on Disaster and Emergency Medicine (WCDEM) held in Beijing, China in May and June of 2011.

Abstracts of Congress oral and poster presentations were published on September 1, 2011 as a supplement to PDM (Volume 26, Supplement 1). The 17th WCDEM was attended by 1,600 representatives from more than 57 nations, and the Congress included 315 oral and 211 poster presentations.

Certain reports and summaries from the Beijing 17th World Congress were published in Volume 27, Issue 3 of PDM. The editorial staff of PDM is pleased to present the following additional reports and session summaries.

Reports and session summaries of the 17th World Congress on Disaster and Emergency Medicine. Prehosp Disaster Med. 2013:28(1):1-7.

Paramedic intercepts with basic life support ambulance services in rural Minnesota

INTRODUCTION

In rural Minnesota, it is common for paramedics providing advanced life support (ALS) to rendezvous with ambulances providing only basic life support (BLS). These "intercepts" presumably allow for a higher level of care when patients have certain problems or need ALS interventions. The aim of this study was to review and understand the frequency of paramedic intercepts with regard to the actual care rendered and transport urgency (lights and sirens vs. none).

METHODS

All paramedic intercepts occurring between January 2003 and December 2007 for one multi-site emergency medical services (EMS) provider were reviewed for ALS interventions and treatments provided. In addition, the urgency of responses to the dispatch call or "intercept" and transport to a receiving facility were analyzed.

RESULTS

During the study period, 1,675 paramedic intercepts occurred and were reviewed. The ALS ambulances responded to the dispatch emergently (lights and sirens) in 97.5% of intercepts (1,633), but emergently transported only 24.2% of the patients (405). Paramedics performed no interventions above BLS levels in 11.6% (194) of the cases. Of the remaining 1,481 patients who received ALS interventions, 955 (64.4%) received no treatment or diagnostic testing other than electrocardiographic monitoring, intravenous access, or both.

CONCLUSIONS

A significant discrepancy between emergent responses and actual ALS care rendered during intercept calls was demonstrated. Given the significant rate of EMS worker fatalities and transferable patient care costs, further study is needed to determine whether costs and safety are potentially improved by decreasing emergent responses. Future directions include developing or emulating Medical Priority Dispatch System triage protocols for advanced services providing intercepts. In addition, further study of patient outcomes between intercept and non-intercept cases is necessary.

Initial emergency medical dispatching and prehospital needs assessment: a prospective study of the Swedish ambulance service

OBJECTIVES

To evaluate the setting of priorities and patients' need for the ambulance service.

METHODS

A prospective, consecutive study was conducted during a 6-week period. The ambulance staff completed a questionnaire assessing each patient's need for prehospital care. In addition to the questionnaire, data were extracted from the ambulance medical records for each case.

RESULTS

The study included 1977 ambulance assignments. The results show that there is a substantial safety margin in the priority assessments made by the emergency medical dispatch operators, where the ambulance staff support the safety margin for initial priorities, despite the lack of at-the-scene confirmation. At-the-scene assessments indicated that 10% of all patients had potentially life-threatening conditions or no signs of life, but the advanced life support units were not systematically involved in these serious cases. The results even showed that one-third of the patients for whom an ambulance was assigned did not need the ambulance service according to the assessment made by the ambulance staff.

CONCLUSION

Using the criteria-based dispatch protocol, the personnel at the emergency medical dispatch centres work with a safety margin in their priority assessments for ambulance response. Generally, this 'overtriage' and safety margin for initial priority settings were supported as appropriate by the ambulance staff. According to the judgement of the ambulance staff, one-third of all the patients who were assigned an ambulance response did not require ambulance transport.

The demand for prehospital advanced life support and the appropriateness of dispatch in Taipei

INTRODUCTION

Implementing prehospital advanced life support (ALS) services requires more medical and societal resources in training and equipment. The actual demand for ALS services in our communities was not clear. To ensure good use of expensive resources, it is important to evaluate the demand and appropriateness of ALS services before full-scale implementation takes place.

OBJECTIVE

To evaluate the rate and characteristics of demand for ALS, and the appropriateness of ALS dispatch of the emergency medical service (EMS) system in metropolitan Taipei City.

METHODS

A retrospective, cross-sectional analysis of the EMS records of Taipei City Fire Department from April 1999 to December 2000 was conducted. Stratified random sampling of all EMS records in the second week of January, April, July and October of 2000 were obtained, along with the corresponding ALS dispatch records. Retrospective ALS demand criteria, including the chief complaints, mechanisms of injury/illness, initial vital signs and types of care rendered, were developed to estimate the rate of ALS demand. ALS demand is expressed as the percentage of cases fulfilling ALS criteria over the total number of EMS cases. Appropriate ALS dispatches were those ALS dispatches determined as fulfilling the ALS demand criteria.

RESULTS

Among the sampled 5433 EMS cases, 490 (9.02%) were determined as a demand for ALS care. ALS demands varied from region to region, and were higher during winter months and afternoon rush hours. There were 175 actual ALS dispatches, accounting for 3.22% of the sampled EMS services. The triage performance was suboptimal: the appropriateness of ALS dispatch was 37.14%; the overtriage rate was 72.86%.

CONCLUSION

Around nine percent of EMS calls demand ALS services. The current triage performance for proper ALS dispatch was suboptimal. A correct ALS dispatch protocol and more dispatcher training programmes should be established in the communities to ensure best use of valuable ALS resources.

Epidemiologic intervention framework of a prehospital emergency medical service

OBJECTIVES

To describe and analyze the characteristics of prehospital medical assistance provided by the Madrid Municipal Emergency and Civil Rescue & Protection Service (SAMUR); and, based on the epidemiologic knowledge so gained, to prioritize public health intervention strategies.

METHODS

A retrospective cross-sectional analysis of all medical services performed by the SAMUR-Protección Civil in 2001 and 2002. Study variables included causes, response times, hour, day of the week, month, mobile resource, Municipal District, and pathology. For analysis purposes, the relevant data were linked to Access 97 via Open Database Connectivity. Statistical analysis was performed using the SPSS computer software package, with Spearman's correlation coefficient and analysis of variance. Values were deemed statistically significant at p < 0.05.

RESULTS

The study population comprised the 97,937 and 101,438 interventions undertaken in 2001 and 2002, respectively. Mean daily activity in 2002 involved 278 alerts (standard deviation: 46), 95% confidence interval: 273-282. Distributions of the interventions were similar for 2001 and 2002, with peak activity from 1 to 2 pm and 8 to 9 pm, and minimum activity from 6 to 7 am. Activity was at its most intense on Saturdays. The magnitude of the association between the two years by day of the week was 96% (p < 0.001). The Central Municipal District (Centro) triggered 17,875 emergency actions. The prevalent pathology was traumatologic, followed by cardiovascular.

CONCLUSIONS

Epidemiologic description enabled the characteristics of the prehospital assistance procedure to be comprehensively ascertained and quantified. False alarms assume special relevance due to their implications. Emergency medical alerts with a psychosocial component are on the increase, something that must be controlled.

Emergency calls not requiring an urgent ambulance response: expert consensus

OBJECTIVES

This study sought expert consensus about which categories of patients from 248 Medical Priority (MPDS) ambulance dispatch codes might be appropriate for a nonemergency response or for whom dispatch of an ambulance might be appropriately denied if the patient were referred to a more suitable health care provider.

METHODS

A Delphi technique was used. Ten physicians, from the specialities of emergency medicine, general practice, and pre-hospital care formed the expert panel but were blinded to each other's identity. Participants received a written description of the operation of the MPDS and the Delphi technique and voted independently by mail.

RESULTS

Using majority voting, 54 dispatch codes (22%) were recommended for a nonemergency response/referral. This equates to 12.44% of annual emergency calls in a typical UK ambulance service (n = 9,021; 95% confidence interval, 12.21 to 12.69%). The kappa statistic (chance-corrected proportional agreement) between members of the expert panel was 0.62 (substantial).

CONCLUSIONS

The recommended dispatch codes for non-emergency response or referral represent a significant proportion of emergency ambulance calls. Theoretically, the implementation of nonemergency responses could have the benefit of reducing accidents involving emergency ambulances and could lead to improved response times for critically ill patients by freeing up resources. It could also support the targeting of patients to appropriate health care providers on first contact with the health service. However, given the poor reliability of expert opinion, further research using clinical outcome data is required to validate the recommendations made in this article before changing existing ambulance response systems.

Can first responders be sent to selected 9-1-1 emergency medical services calls without an ambulance?

OBJECTIVES

To evaluate the feasibility and safety of initially dispatching only first responders (FRs) to selected low-risk 9-1-1 requests for emergency medical services. First responders are rapidly-responding fire crews on apparatus without transport capabilities, with firefighters trained to at least a FR level and in most cases to the basic emergency medical technician (EMT) level. Low-risk 9-1-1 requests include automatic medical alerts (ALERTs), motor vehicle incidents (MVIs) for which the caller was unable to answer any medical dispatch questions designed to prioritize the call, and 9-1-1 call disconnects (D/Cs).

METHODS

A before-and-after study of patient dispositions was conducted using historical controls for comparison. During the historical control phase of six months, one year prior to the study phase, basic life support ambulances (staffed with two basic EMTs) were dispatched to selected low-risk 9-1-1 incidents. During the six-month study phase, a fire FR crew equipped with automated external defibrillators (AEDs) was sent initially without an ambulance to these incidents.

RESULTS

For ALERTs (n = 290 in historical group vs. 330 in study group), there was no statistical difference in the transport rate (7% vs 10%), but there was a statistically significant increase in the follow-up use of advanced life support (ALS) (1% vs 4%, p = 0.009). No patient in the ALERTs historical group required airway management, while one patient in the study group received endotracheal intubation. No patient required defibrillation in either group. Analysis of the MVIs showed a significant decrease (p < 0.0001) in the patient transport rate from 39% of controls to 33% of study patients, but no change in the follow-up use of ALS interventions (2% for each group). For both the ALERTs and MVIs, the FR's mean response time was faster than ambulances (p < 0.0001). Among the 9-1-1 D/Cs with FRs only (n = 1,028), 15% were transported and 43 (4%) received subsequent ALS care. Four of these patients (0.4%) received intubation and two (0.2%) required defibrillation. However, no patient was judged to have had adverse outcomes as a result of the dispatch protocol change.

CONCLUSIONS

Fire apparatus crews trained in the use of AEDs can safely be used to initially respond alone (without ambulances) to selected, low-risk 9-1-1 calls. This tactic improves response intervals while reducing ambulance responses to these incidents.

Emergency medical dispatch

EMD will always remain somewhat of an imprecise science by nature. 911 is, after all, the access point for lifesaving assistance, and citizens must have absolute freedom to this service. The consequence of having the freedom to request help from any location at any time is that some individuals will use it for the wrong reasons. Present-day dispatchers must serve ever-broadening communities with multiple languages, cultural diversity, and unique health needs. Along with other essential personnel that make up the fabric of the public safety net, emergency medical dispatchers have now become essential to the provision of time-critical skills and compassion for perceived medical emergency.

Performance measurements in emergency medical services

With the strong encouragement of leading health care agencies, business principles are being implemented throughout health care, including emergency medical services (EMS). The reason is simple--quality of care can be enhanced by incorporating the management concepts of continuous quality improvement (CQI). The CQI process couples carefully identified, measurable performance indicators with information systems to monitor, analyze, and trend data. Benchmarking outcomes with other EMS systems allows the identification of "best practices" and the evolution of standards. Emergency medical services professionals must actively participate with the broader health care community in creating performance measurements to ensure that high-quality care is delivered consistently.

The use of emergency medical dispatch protocols to reduce the number of inappropriate scene responses made by advanced life support personnel

OBJECTIVES

To determine whether implementation of an emergency medical dispatch (EMD) system would reduce the rate of inappropriate advanced life support (ALS) utilization, and enable more accurate identification of those patients requiring ALS care.

METHODS

An emergency medical services (EMS) site providing basic life support (BLS) and ALS care to a population of 200,000 served as the study site for calendar year 1996. This study compared the prospective identification of patients as ALS or BLS using EMD with that using chief complaint-based dispatch criteria. Each patient served as his or her own control. The ALS or BLS priority was assigned using both chief complaint and EMD criteria. Chief complaint-based dispatching meant that all patients with preestablished chief complaints received ALS without further triage questions, while EMD allowed the dispatchers to question callers using a scripted set of questions. The outcome measures included the number of calls categorized as ALS or BLS, the number of calls cancelled by BLS, and the number of ALS calls released to BLS care. Yates-corrected chi-square was used for statistical analysis.

RESULTS

There were 11,174 patients enrolled. The use of EMD was associated with a significant decrease in the proportion of calls designated as ALS (44.7% vs 55.8%, p < 0.0001), as well as a significant decrease in the number of ALS responses cancelled by BLS (9.2% vs 23.8%, p < 0.0001) and patients released to BLS by medical control (4.7% vs 7.3%, p < 0.0001).

CONCLUSIONS

Implementation of an EMD system significantly decreased inappropriate ALS dispatching, as defined by decreased rate of ALS cancellations and BLS releases. Further study is needed to see whether other EMD dispatch models may further refine ALS dispatch.

Do emergency medical services dispatch nature and severity codes agree with paramedic field findings?

Emergency medical services (EMS) systems increasingly seek to triage patients to alternative EMS resources. Emergency medical services dispatchers may be asked to perform this triage. New protocols may be necessary. Alternatively, existing protocols may be sufficient for this task. For an existing dispatch protocol to be sufficient, it at least must accurately categorize patient condition and severity based on an external standard.

OBJECTIVE

To examine the extent to which nature codes (NCs), or patient condition codes, and severity codes (SCs) currently assigned in one urban 911 center agree with paramedic field findings. The null hypothesis was that there is no routine agreement (75%) between dispatcher-assigned NC or SC and paramedic-assigned NC or SC for the same patient using the same protocol.

METHODS

Emergency medical services dispatch nature and severity code data and matching out-of-hospital data were prospectively gathered over six months. Dispatch data included the NC: caller-identified problem, and the SC: dispatcher-assessed severity. Each NC is modified by one of three SCs (1, 3, or 9): 1 is emergent, 3 is urgent, and 9 is neither. Paramedics verified and/or corrected dispatcher-assigned NCs and SCs using the same dispatch protocol.

RESULTS

One thousand forty usable cases fell into 33 unique NC/SC combinations. The designation of SC 1 was assigned 275 times, SC 3 was assigned 736 times, and SC 9 was assigned 24 times. The SC was missing five times. The overall NC agreement was 0.70 (95% CI = 0.697 to 0.703). The overall SC agreement was 0.65 (95% CI = 0.645 to 0.655). The NC agreement exceeded 75% for ten (59%) NC/SC combinations. The SC agreement exceeded 75% for five (29%) NC/SC combinations. There was both NC and SC agreement for four (24%) combinations: urgent breathing problems, urgent diabetic problems, urgent falls, and urgent overdoses. The greatest NC/SC disagreement occurred within emergent and urgent traffic crashes. Paramedics adjusted SC toward lower severity 29% of the time and toward higher severity 5.4% of the time. There was no upward SC adjustment for eight (47%) combinations.

CONCLUSIONS

Certain dispatcher-assigned NC and SC codes and NC/SC combinations achieved the study threshold. Overall agreement failed to achieve the threshold. The lowest SC level was rarely assigned, preventing a meaningful analysis of all severity levels.

EMS Agenda for the Future: where we are...where we want to be

During the past 30 years, emergency medical services (EMS) in the United States have experienced explosive growth. The American health care system is now transforming, providing an opportune time to examine what we have learned over the past three decades in order to create a vision for the future of EMS. Over the course of several months, a multidisciplinary steering committee collaborated with hundreds of EMS-interested individuals, organizations, and agencies to develop the EMS Agenda for the Future. Fourteen EMS attributes were identified as requiring continued development in order to realize the vision established within the Agenda. They are integration of health services, EMS research, legislation and regulation, system finance, human resources, medical direction, education systems, public education, prevention, public access, communication systems, clinical care, information systems, and evaluation. Discussion of these attributes provides important guidance for achieving a vision for the future of EMS that emphasizes its critical role in American health care.

Performance of a system to determine EMS dispatch priorities

Inappropriate use of emergency medical services (EMS) for nonemergencies strains EMS resources and limits efficiency. Protocol-driven dispatch systems attempt to correct the imbalance that exists between demand and available resources by prioritizing 911 calls. This study compared dispatch priority decisions with apparent patient need, based on emergency department (ED) presentation, by matching 320 ED charts with corresponding EMS dispatch and run information. The priorities assigned by the system based on dispatch information were compared with those assigned by a three-member panel of physicians based on ED presentation. The physicians and dispatchers agreed on the need for advanced life support (ALS) versus basic life support (BLS) transport 74% of the time. There was only 43% agreement on the more detailed 4-level classification system. The system assigned the highest level of dispatch utilizing combined ALS and first responders to a significantly greater degree than did the physicians. It was concluded that protocol systems for setting dispatch priorities utilize EMS resources to a higher degree than actually required based on ED presentation.

Emergency medical services priority dispatch

STUDY OBJECTIVE

To test the ability of a locally designed priority dispatch system to safely exclude the need for advanced life support (ALS).

DESIGN

Retrospective review of emergency medical services (EMS) incident records to determine how often the lone dispatch of basic life support (BLS) units, staffed with basic emergency medical technicians, subsequently required or involved ALS care.

SETTING

A large centralized municipal EMS system with a tiered ALS/BLS ambulance response. All BLS units carry automated defibrillators.

MEASUREMENTS

Consecutive EMS records (35,075) were reviewed by computerized search for ALS procedures. Records indicating ALS procedures were tabulated and then manually reviewed for the nature of and probable indication for the ALS intervention.

INTERVENTION

Brief sequences of computer-stored questions that help dispatchers identify (or exclude) signs and symptoms indicating the need for ALS.

RESULTS

The dispatch triage system spared ALS units from initial dispatch in 14,100 of the EMS incidents (40.2%), increasing their availability and use for more serious calls. Among these 14,100 cases, only 41 patients (0.3%) later received drugs such as nitroglycerin and naloxone; another 27 patients (0.2%) received resuscitative interventions such as epinephrine or defibrillation. Furthermore, on closer analysis, the immediate presence of a paramedic might have provided a true potential for advantage in outcome for only five or six patients (less than 0.04 of the 14,100 BLS dispatches). Meanwhile, many important operational, fiscal, and cost-effective patient care benefits were realized with this system.

CONCLUSION

A computer-aided dispatch triage algorithm can facilitate improvements in both EMS system operations and prehospital patient care by safely and reliably identifying EMS incidents requiring only BLS.