Ability of the medical priority dispatch system protocol to predict the acuity of "unknown problem" dispatch response levels

Clinical decision support system in emergency telephone triage: A scoping review of technical design, implementation and evaluation

OBJECTIVES

Emergency department overcrowding could be improved by upstream telephone triage. Emergency telephone triage aims at managing and orientating adequately patients as early as possible and distributing limited supply of staff and materials. This complex task could be improved with the use of Clinical decision support systems (CDSS). The aim of this scoping review was to identify literature gaps for the future development and evaluation of CDSS for Emergency telephone triage.

MATERIALS AND METHODS

We present here a scoping review of CDSS designed for emergency telephone triage, and compared them in terms of functional characteristics, technical design, health care implementation and methodologies used for evaluation, following the PRISMA-ScR guidelines.

RESULTS

Regarding design, 19 CDSS were retrieved: 12 were knowledge based CDSS (decisional algorithms built according to guidelines or clinical expertise) and 7 were data driven (statistical, machine learning, or deep learning models). Most of them aimed at assisting nurses or non-medical staff by providing patient orientation and/or severity/priority assessment. Eleven were implemented in real life, and only three were connected to the Electronic Health Record. Regarding evaluation, CDSS were assessed through various aspects: intrinsic characteristics, impact on clinical practice or user apprehension. Only one pragmatic trial and one randomized controlled trial were conducted.

CONCLUSION

This review highlights the potential of a hybrid system, user tailored, flexible, connected to the electronic health record, which could work with oral, video and digital data; and the need to evaluate CDSS on intrinsic characteristics and impact on clinical practice, iteratively at each distinct stage of the IT lifecycle.

Relationship Between Nursing Students' Awareness of Disaster, Preparedness for Disaster, Willingness to Participate in Disaster Response, and Disaster Nursing Competency

OBJECTIVE

This study was conducted to provide basic data for preparing a disaster nursing education program. It examined the degree of nursing students' disaster awareness, disaster preparedness, willingness to participate in disaster response, and disaster nursing competency, aiming to determine the relationship between these attributes.

METHODS

This was a descriptive research study. The participants were 163 nursing students. The data collected from the participants were analyzed via descriptive statistics and Pearson's correlation coefficients.

RESULTS

Disaster awareness showed a positive correlation with a willingness to participate in a disaster response. Further, disaster preparedness and willingness to participate in a disaster response showed a positive correlation with disaster nursing capacity. Disaster awareness did not show a significant correlation with disaster preparedness and disaster nursing competency. Last, disaster preparedness did not show a significant correlation with willingness to participate in a disaster response.

CONCLUSIONS

It is necessary to improve nursing students' disaster awareness, disaster preparation, disaster response participation willingness, and disaster nursing competency. It is imperative to develop disaster nursing education programs to strengthen students' capabilities in a comprehensive manner.

The Development of Consensus-Based Descriptors for Low-Acuity Emergency Medical Services Cases for the South African Setting

INTRODUCTION

Emergency Medical Services (EMS) are designed to respond to and manage patients experiencing life-threatening emergencies; however, not all emergency calls are necessarily emergent and of high acuity. Emergency responses to low-acuity patients affect not only EMS, but other areas of the health care system. However, definitions of low-acuity calls are vague and subjective; therefore, it was necessary to provide a clear description of the low-acuity patient in EMS.

AIM

The goal of this study was to develop descriptors for "low-acuity EMS patients" through expert consensus within the EMS environment.

METHODS

A Modified Delphi survey was used to develop call-out categories and descriptors of low acuity through expert opinion of practitioners within EMS. Purposive, snowball sampling was used to recruit 60 participants, of which 29 completed all three rounds. An online survey tool was used and offered both binary and free-text options to participants. Consensus of 75% was accepted on the binary options while free text offered further proposals for consideration during the survey.

RESULTS

On completion of round two, consensus was obtained on 45% (70/155) of the descriptors, and a further 30% (46/155) consensus was obtained in round three. Experts felt that respiratory distress, unconsciousness, chest pain, and severe hemorrhage cannot be considered low acuity. For other emergency response categories, specific descriptors were offered to denote a case as low acuity.

CONCLUSION

Descriptors of low acuity in EMS are provided in both medical and trauma cases. These descriptors may not only assist in the reduction of unnecessary response and transport of patients, but also assist in identifying the most appropriate response of EMS resources to call-outs. Further development and validation are required of these descriptors in order to improve accuracy and effectiveness within the EMS dispatch environment.

Association between ambulance dispatch priority and patient condition

OBJECTIVE

To compare chief complaints of the Medical Priority Dispatch System in terms of the match between dispatch priority and patient condition.

METHODS

This was a retrospective whole-of-population study of emergency ambulance dispatch in Perth, Western Australia, 1 January 2014 to 30 June 2015. Dispatch priority was categorised as either Priority 1 (high priority), or Priority 2 or 3. Patient condition was categorised as time-critical for patient(s) transported as Priority 1 to hospital or who died (and resuscitation was attempted by paramedics); else, patient condition was categorised as less time-critical. The χ² statistic was used to compare chief complaints by false omission rate (percentage of Priority 2 or 3 dispatches that were time-critical) and positive predictive value (percentage of Priority 1 dispatches that were time-critical). We also reported sensitivity and specificity.

RESULTS

There were 211 473 cases of dispatch. Of 99 988 cases with Priority 2 or 3 dispatch, 467 (0.5%) were time-critical. Convulsions/seizures and breathing problems were highlighted as having more false negatives (time-critical despite Priority 2 or 3 dispatch) than expected from the overall false omission rate. Of 111 485 cases with Priority 1 dispatch, 6520 (5.8%) were time-critical. Our analysis highlighted chest pain, heart problems/automatic implanted cardiac defibrillator, unknown problem/collapse, and headache as having fewer true positives (time-critical and Priority 1 dispatch) than expected from the overall positive predictive value.

CONCLUSION

Scope for reducing under-triage and over-triage of ambulance dispatch varies between chief complaints of the Medical Priority Dispatch System. The highlighted chief complaints should be considered for future research into improving ambulance dispatch system performance.

Non-specific complaints in the ambulance; predisposing structural factors

BACKGROUND

The pre-hospital assessment non-specific complaint (NSC) often applies to patients whose diagnosis does not match any other specific assessment correlating to particular symptoms or diseases, though some previous studies have found them to be related to serious underlying conditions. The aim was to identify whether the structural factors such as urgency according to the dispatch priority of the Emergency Medical Communication Centre (EMCC) or work load in the Emergency Medical Services (EMS) are predisposing factors for the assessment of NSC instead of a specific assessment.

METHODS

All patients with assessed condition NSCs by the EMS to Södersjukhuset during 2011 (n = 493) were compared with gender- and age-matched controls (n = 493), which were randomly drawn from all patients with specific conditions in the EMS, regarding day of week, time of day and priority set by EMCC with chi-squared tests and multivariate logistic regression models.

RESULTS

Among patients with NSCs, more were females (58 %) and the median age was 82. Almost all patients were categorized with NSCs during the daytime (8 a.m. to 9 p.m.), i.e. 450 (91 %) as compared to 373 (75 %) of those with specific conditions (p < 0.01). The risk of having an EMS dispatched as low priority by the EMCC was almost doubled among patients with NSCs compared to controls (OR 1.97, 95 % CI 1.38-2.79).

CONCLUSIONS

Since patients with NSCs appear most frequently during the hours with most transportations for the EMS, i.e. 10 a.m. to 2 p.m., and the risk of having the assessment NSC was doubled if the EMCC dispatched EMS as low priority, structural factors might be predisposing factors for the assessment.

Patient safety in ambulance services: a scoping review

Background

The role of ambulance services has changed dramatically over the last few decades with the introduction of paramedics able to provide life-saving interventions, thanks to sophisticated equipment and treatments available. The number of 999 calls continues to increase, with adverse events theoretically possible with each one. Most patient safety research is based on hospital data, but little is known concerning patient safety when using ambulance services, when things can be very different. There is an urgent need to characterise the evidence base for patient safety in NHS ambulance services.

Objective

To identify and map available evidence relating to patient safety when using ambulance services.

Design

Mixed-methods design including systematic review and review of ambulance service documentation, with areas for future research prioritised using a Delphi process.

Setting and participants

Ambulance services, their staff and service users in UK.

Data sources

A wide range of data sources were explored. Multiple databases, reference lists from key papers and citations, Google and the NHS Confederation website were searched, and experts contacted to ensure that new data were included in the review. The databases MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Science, Science Direct, Emerald, Education Resources Information Center (ERIC), Applied Social Sciences Index and Abstracts, Social Services Abstracts, Sociological Abstracts, International Bibliography of the Social Sciences (IBSS), PsycINFO, PsycARTICLES, Health Management Information Consortium (HMIC), NHS Evidence, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE), NHS Economic Evaluation Database (NHS EED),Health Technology Assessment, the FADE library, Current Awareness Service for Health (CASH), OpenDOAR (Directory of Open Access Repositories) and Open System for Information on Grey Literature in Europe (OpenSIGLE) and Zetoc (The British Library's Electronic Table of Contents) were searched from 1 January 1980 to 12 October 2011. Publicly available documents and issues identified by National Patient Safety Agency (NPSA), NHS Litigation Authority (NHSLA) and coroners’ reports were considered. Opinions and perceptions of senior managers, ambulance staff and service users were solicited.

Review methods

Data were extracted from annual reports using two-stage thematic analysis, data from quality accounts were collated with safety priorities tabulated and considered using thematic analysis, NPSA incident report data were collated and displayed comparatively using descriptive statistics, claims reported to NHSLA were analysed to identify number and cost of claims from mistakes and/or poor service, and summaries of coroners’ reports were assessed using thematic analysis to identify underlying safety issues. The depth of analysis is limited by the remit of a scoping exercise and availability of data.

Results

We identified studies exploring different aspects of safety, which were of variable quality and with little evidence to support activities currently undertaken by ambulance services. Adequately powered studies are required to address issues of patient safety in this service, and it appeared that national priorities were what determined safety activities, rather than patient need. There was inconsistency of information on attitudes and approaches to patient safety, exacerbated by a lack of common terminology.

Conclusion

Patient safety needs to become a more prominent consideration for ambulance services, rather than operational pressures, including targets and driving the service. Development of new models of working must include adequate training and monitoring of clinical risks. Providers and commissioners need a full understanding of the safety implications of introducing new models of care, particularly to a mobile workforce often isolated from colleagues, which requires a body of supportive evidence and an inherent critical evaluation culture. It is difficult to extrapolate findings of clinical studies undertaken in secondary care to ambulance service practice and current national guidelines often rely on consensus opinion regarding applicability to the pre-hospital environment. Areas requiring further work include the safety surrounding discharging patients, patient accidents, equipment and treatment, delays in transfer/admission to hospital, and treatment and diagnosis, with a clear need for increased reliability and training for improving handover to hospital.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

Variations in contact patterns and dispatch guideline adherence between Norwegian emergency medical communication centres--a cross-sectional study

Background

The 19 Norwegian Emergency medical communication centres (EMCCs) use Norwegian Index for medical emergency assistance (Index) as dispatch guidelines. Little is known about the use of Index, nor its validity. We aimed to document the epidemiology of contacts made to the public emergency medical phone number and the operators’ self-reported use of Index as a first step towards a validation study.

Methods

We registered all medical emergency calls to the EMCCs during a 72 h period in a national cross sectional study. We subsequently sent a questionnaire to all EMCC operators in Norway, asking how they use Index. A combined outcome variable “use of Index” was computed through a Likert scale, range 1–5. Regression models were used to examine factors influencing use.

Results

2 298 contacts were included. National contact rate was 56/1 000 inhabitants per year, range between EMCCs 34 – 119. Acute contact (life-threatening situations) rate was 21/1 000 per year, range between EMCCs 5 – 31. Index criteria 6 – ’Unresolved problem’ accounts for 20% of the 113 contacts, range between EMCCs 10 – 42%. The mean use of Index was 3.95 (SD 0.39), corresponding to “more than 75% of emergency calls”. There were differences in use of Index on EMCC level, range 3.7 – 4.4, and a multi regression model explained 23.4% of the variation in use. Operators working rotation with ground ambulance services reported reduced use of Index compared to operators not working in rotation, while distinct EMCC focus on Index increased use of Index compared to EMCCs with no focus on Index. Use of electronic records and operators experience were the main reasons given for not using Index.

Conclusions

There is a large variation between the EMCCs with regard to both contact patterns and use of Index. There is a relatively high overall self-reported use of Index by the operators, with variations on both individual and EMCC level.

Which emergency medical dispatch codes predict high prehospital nontransport rates in an urban community?

BACKGROUND

The Medical Priority Dispatch System (MPDS) is a commonly used computer-based emergency medical dispatch (EMD) system that is widely used to prioritize 9-1-1 calls and optimize resource allocation. There are five major priority classes used to dispatch 9-1-1 calls in the San Francisco System; Alpha codes are the lowest priority (lowest expected acuity) and Echo are the highest priority.

OBJECTIVE

We sought to determine which MPDS dispatch codes are associated with high prehospital nontransport rates (NTRs).

METHODS

All unique MPDS call categories from 2009 in a highly urbanized, two-tier advanced life support (ALS) system were sorted according to highest NTRs. There are many reasons for nontransport, such as "gone on arrival," and "patient denied transport." Those categories with greater than 100 annual calls were further evaluated. MPDS groups that included multiple categories with NTRs exceeding 25% were then identified and each category was analyzed. Results. EMS responded to a total of 81,437 calls in 2009, of which 18,851 were not transported by EMS. The majority of the NTRs were found among "cardiac/ respiratory arrest/death," "assault/sexual assaults," "unknown problem/man down," "traffic/transportation accidents," and "unconscious/fainting." "Cardiac or respiratory arrest/death -obvious death" (9B1) had the highest overall nontransport rate, 99.25% (1/134), most likely due to declaration of death. "Unknown problem -man down -medical alert notification" had the second highest NTR, 67.22% (138/421). However, Echo priority codes had the highest overall nontransport rates (45.45%) and Charlie had the lowest (13.84%).

CONCLUSIONS

The nontransport rates of individual MPDS categories vary considerably and should be considered in any system design. We identified 52 unique call categories to have a 25% or greater NTR, 18 of which exceeded 40%. The majority of NTRs occurred among the "cardiac/respiratory arrest/death," "assault/sexual assaults," "unknown problem/man down," "traffic/transportation accidents," and "unconscious/fainting" categories. The higher the priority code within each subset (AB vs. CDE), the less likely the patient was to be transported. Charlie priority codes had a lower NTR than Delta, and Delta was lower than Echo. Charlie codes were therefore the strongest predictors of hospital transport, while Echo codes (highest priority) were those with the highest nontransport rates and were the worst predictors of hospital transport in the emergent subset.

Implementing a nationwide criteria-based emergency medical dispatch system: a register-based follow-up study

BACKGROUND

A criteria-based nationwide Emergency Medical Dispatch (EMD) system was recently implemented in Denmark. We described the system and studied its ability to triage patients according to the severity of their condition by analysing hospital admission and case-fatality risks.

METHODS

This was a register-based follow-up study of all 1-1-2 calls in a 6-month period that were triaged according to the Danish Index - the new criteria-based dispatch protocol. Danish Index data were linked with hospital and vital status data from national registries. Confidence intervals (95%) for proportions with binomial data were computed using exact methods. To test for trend the Wald test was used.

RESULTS

Information on level of emergency according to the Danish Index rating was available for 67,135 patients who received ambulance service. Emergency level A (urgent cases) accounted for 51.4% (n = 34,489) of patients, emergency level B for 46.3% (n = 31,116), emergency level C for 2.1% (n = 1,391) and emergency level D for 0.2% (n = 139). For emergency level A, the median time from call receipt to ambulance dispatch was 2 min 1 s, and the median time to arrival was 6 min 11 s. Data concerning admission and case fatality was available for 55,270 patients. The hospital admission risk for emergency level A patients was 64.4% (95% CI = 63.8-64.9). There was a significant trend (p < 0.001) towards lower admission risks for patients with lower levels of emergency. The case fatality risk for emergency level A patients on the same day as the 1-1-2 call was 4.4% (95% CI = 4.1-4.6). The relative case-fatality risk among emergency level A patients compared to emergency level B-D patients was 14.3 (95% CI: 11.5-18.0).

CONCLUSION

The majority of patients were assessed as Danish Index emergency level A or B. Case fatality and hospital admission risks were substantially higher for emergency level A patients than for emergency level B-D patients. Thus, the newly implemented Danish criteria-based dispatch system seems to triage patients with high risk of admission and death to the highest level of emergency. Further studies are needed to determine the degree of over- and undertriage and prognostic factors.

Emergency medical dispatch codes association with emergency department outcomes

BACKGROUND

Emergency medical dispatch systems are used to help categorize and prioritize emergency medical services (EMS) resources for requests for assistance.

OBJECTIVE

We examined whether a subset of Medical Priority Dispatch System (MPDS) codes could predict patient outcomes (emergency department [ED] discharge versus hospital admission/ED death).

METHODS

This retrospective observational cohort study analyzed requests for EMS through a single public safety answering point (PSAP) serving a mixed urban, suburban, and rural community over one year. Probabilistic matching was used to link subjects. Descriptive statistics, 95% confidence intervals (CIs), and logistic regression were calculated for the 107 codes and code groupings (9E vs. 9E1, 9E2, etc.) that were used 50 or more times during the study period.

RESULTS

Ninety percent of PSAP records were matched to EMS records and 84% of EMS records were matched to ED data, resulting in 26,846 subjects with complete records. The average age of the cohort was 46.2 years (standard deviation [SD] 24.8); 54% were female. Of the transported patients, 70% were discharged from the ED, with nine dispatch codes demonstrating a 90% or greater predictive power. Three code groupings had more than 60% predictive power for admission/death. Subjects aged 65 years and older were found to be at increased risk for admission/death in 33 dispatch codes (odds ratio [OR] 2.0 [95% confidence interval 1.3-3.0] to 19.6 [5.3-72.6]).

CONCLUSIONS

A small subset (8% of codes; 7% by call volume) of MPDS codes were associated with greater than 90% predictive ability for ED discharge. Older adults are at increased risk for admission/death in a separate subset of MPDS codes, suggesting that age criteria may be useful to identify higher-acuity patients within the MPDS code. These findings could assist in prehospital/hospital resource management; however, future studies are needed to validate these findings for other EMS systems and to investigate possible strategies for improvements of emergency response systems.

Association between Patient Unconscious or Not Alert Conditions and Cardiac Arrest or High-Acuity Outcomes within the Medical Priority Dispatch System “Falls” Protocol

Introduction:

Falls are one of the most common types of complaints received by 9-1-1 emergency medical dispatch centers. They can be accidental or may be caused by underlying medical problems. Though not alert” falls patients with severe outcomes mostly are “hot” transported to the hospital, some of these cases may be due to other acute medical events (cardiac, respiratory, circulatory, or neurological), which may not always be apparent to the emergency medical dispatcher (EMD) during call processing.

Objectives:

The objective of this study was to characterize the risk of cardiac arrest and “hot-transport” outcomes in patients with “not alert” condition, within the Medical Priority Dispatch System (MPDS®) Falls protocol descriptors.

Methods:

This retrospective study used 129 months of de-identified, aggregate, dispatch datasets from three US emergency communication centers. The communication centers used the Medical Priority Dispatch System version 11.3–OMEGA type (released in 2006) to interrogate Emergency Medical System callers, select dispatch codes assigned to various response configurations, and provide pre-arrival instructions. The distribution of cases and percentages of cardiac arrest and hot-transport outcomes, categorized by MPDS® code, was profiled. Assessment of the association between MPDS® Delta-level 3 (D-3) “not alert” condition and cardiac arrest and hot-transport outcomes then followed.

Results:

Overall, patients within the D-3 and D-2 “long fall” conditions had the highest proportions (compared to the other determinants in the “falls” protocol) of cardiac arrest and hot-transport outcomes, respectively. “Not alert” condition was associated significantly with cardiac arrest and hot-transport outcomes (p < 0.001).

Conclusions:

The “not alert” determinant within the MPDS® “fall” protocol was associated significantly with severe outcomes for short falls (<6 feet; 2 meters) and ground-level falls. As reported to 9-1-1, the complaint of a “fall” may include the presence of underlying conditions that go beyond the obvious traumatic injuries caused by the fall itself.

Does Emergency Medical Dispatch Priority Predict Delphi Process-Derived Levels of Prehospital Intervention?

Objective:

The Medical Priority Dispatch System (MPDS) is an emergency medical dispatch system widely used to prioritize 9-1-1 calls and optimize resource allocation. This study evaluates whether the assigned priority predicts a Delphi process-derived level of prehospital intervention in each emergency medical dispatch category.

Methods:

All patients given a MPDS priority in a suburban California county from 2004–2006 were included. A Delphi process of emergency medical services (EMS) professionals in another system developed the following categories of prehospital treatment representing increasing acuity, which were adapted for this study: advanced life support (ALS) intervention, ALS–Stat, and ALS–Critical. The sensitivities and specificities of MPDS priority for level of prehospital intervention were determined for each MPDS category.

Results:

A total of 65,268 patients met inclusion criteria, representing 61% of EMS calls during the study period. The overall sensitivities of high-priority dispatch codes for ALS, ALS-Stat, and ALS-Critical interventions were 83% (95% confidence interval 83–84%), 83% (82–84%), and 94% (92–96%). Overall specificities were: ALS, 32% (31–32%); ALS-Stat, 31% (30–31%); and ALS-Critical 28% (28–29%). Compared to calls assigned to a low priority, calls with high-priority dispatch codes were more likely to receive ALS interventions by 22%, ALS-Stat by 20%, and ALS-Critical by 32%. A low priority dispatch code decreased the likelihood of ALS interventions by 48%, ALS-Stat by 45%, and ALS-Critical by 80%. Among high-priority dispatch codes, the rates of interventions were: ALS 26%, ALS-Stat 22%, and ALS-Critical 1.5%, all of which were significantly greater than low-priority calls (p <0.05) [ALS 13%, ALS-Stat 11%, and ALS-Critical 0.2%]. Major MPDS were categories with high sensitivities (>95%) for ALS interventions included breathing problems, cardiac or respiratory arrest/death, chest pain, stroke, and unconscious/fainting; these categories had an average specificity of 3%. Medical Priority Dispatch System categories such as back pain, unknown problem, and traumatic injury had sensitivities for ALS interventions <15%.

Conclusions:

The MPDS is moderately sensitive for the Delphi process derived ALS, ALS-Stat, and ALS-Critical intervention levels, but non-specific. A low MPDS priority is predictive of no prehospital intervention. A high priority, however, is of little predictive value for ALS, ALS-Stat, or ALSCritical interventions.

In out-of-hospital cardiac arrest patients, does the description of any specific symptoms to the emergency medical dispatcher improve the accuracy of the diagnosis of cardiac arrest: a systematic review of the literature

AIM

We sought to determine if, in patients with out-of-hospital cardiac arrest (OHCA), the description of any specific symptoms to the emergency medical dispatcher (EMD) improved the accuracy of the diagnosis of cardiac arrest.

METHODS

For this systematic review, we searched MEDLINE, EMBASE and the Cochrane Library with no restrictions, and hand-searched the gray literature. Eligible studies included dispatcher interaction with callers reporting OHCA, and reported diagnosis of cardiac arrest. Two independent reviewers used standardized forms and procedures to review papers for inclusion, quality, and to extract data from eligible studies. Findings were peer-reviewed by the International Liaison Committee on Resuscitation.

RESULTS

We identified 494 citations; 74 were selected for full evaluation (kappa=0.70) and 23 were included (kappa=0.68), including six before-after, two case-control, and 15 descriptive studies. One before-after study and ten descriptive studies report that inquiring about consciousness and breathing status can help dispatchers recognize cardiac arrest with moderate sensitivity [ranging from 38% to 97%], and high specificity [ranging from 95% to 99%]. One case-control study, three before-after studies, and four observational studies report that abnormal breathing is a significant barrier to cardiac arrest recognition. One before-after study and two descriptive studies report that seizure activity can be a manifestation of cardiac arrest.

CONCLUSION

Dispatchers should recognize cardiac arrest when a victim is described as unconscious and not breathing or not breathing normally, and consider cardiac arrest when generalized seizure is described. They should receive specific instructions on how to best recognize the presence of abnormal breathing.

How many emergency dispatches occurred per cardiac arrest?

BACKGROUND

The Medical Priority Dispatch System (MPDS) is an emergency medical dispatch (EMD) system that is widely used to prioritize 9-1-1 calls and optimize resource allocation. Calls are assigned an MPDS determinant, which includes a number (1-32) representing chief complaint and priority (Alpha through Echo) representing acuity.

OBJECTIVE

This study evaluates the number of emergency dispatches per cardiac arrest (NOD-CA) in cardiac arrest and non-cardiac arrest MPDS determinants.

METHODS

All patients assigned a determinant by MPDS from January 1, 2008 to June 30, 2009 in a large metropolitan area were included. Prehospital electronic patient care records were linked with dispatch data. For each MPDS determinant, the number of calls for which the paramedic impression was listed as "Cardiac Arrest - Non-Traumatic" was tabulated. The NOD-CA was calculated for each cardiac arrest and non-cardiac arrest MPDS determinant. Non-MPDS calls with cardiac arrests were analyzed separately.

RESULTS

A total of 101,642 patients were included. Among them, 555 had "Cardiac Arrest - Non-Traumatic" listed as the paramedic impression. The Cardiac/Respiratory Arrest/Death protocol had the highest number of cardiac arrests (285), followed by Breathing Problems (99) and Unconscious/Fainting (76). Overall, 183 dispatched occurred for each cardiac arrest, 131 of which resulted in a lights and sirens response. The NOD-CA was 7 in the Cardiac Arrest/Death protocol, 122 in Breathing Problems, and 104 in Unconscious/Fainting. 31 Cardiac arrests occurred in non-MPDS dispatch categories (N=62,989), most of which were calls for medical assistance from police or fire units.

CONCLUSIONS

MPDS was designed to detect cardiac arrest with high sensitivity, leading to a significant degree of mistriage. The number of dispatches for each cardiac arrest may be a useful way to quantify the degree of mistriage and optimize EMS dispatch. This large descriptive study revealed a low NOD-CA in most cardiac arrest MPDS determinants. We demonstrated significant variability in the NOD-CA among non-cardiac arrest MPDS determinants, and few cardiac arrests in non-MPDS dispatch categories.

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.

Profile of emergency medical dispatch calls for breathing problems within the medical priority dispatch system protocol

INTRODUCTION

A common chief complaint to emergency dispatch communication centers worldwide is "breathing problems". The chief complaint of breathing problems represents a wide spectrum of underlying diseases, patient conditions, and onset types. The current debate is on the potential ability of a dispatch protocol to safely and with high specificity, differentiate patients with minor or non-critical conditions from those conditions that pose risk to the patient and require advanced life support evaluation and care. This issue also has extended into the paramedic prehospital evaluation realm.

OBJECTIVE

The objective of this study was to describe the distribution of Medical Priority Dispatch System (MPDS) codes representing the spectrum of clinical descriptions within the breathing problems chief complaint and their associated outcomes, at the scene and during transport, as determined by [UK] paramedics.

METHODS

A retrospective, one-year study (September 2005 to August 2006) of a de-identified aggregate dataset from the London Ambulance Service (LAS) Trust was evaluated. A profile of the distribution of calls, incidents, patients, and outcomes (cardiac arrest [CA] and blue-in [BI] high acuity i.e., patients transported with lights and siren based on paramedic protocol) for the breathing problems chief complaint was evaluated. Odds ratios and 95% confidence intervals (CI) were used to quantify associations between the MPDS priority level's concurrent asthmatic conditions and outcomes. Two-sided Fisher's exact p-values were obtained to determine statistically significant associations, at a level of0.05.

RESULTS

Sixteen percent (95,848/599,093) of all the patients were classified under the breathing problems chief complaint. Of these 95,848 patients, 367 (0.38%) were CA outcomes, and 7.82% (n = 7,493) were BI outcomes.The Cardiac Arrest Quotient (i.e., the number of CA cases as a percentage of the number of patients) for the ECHO priority level was 46 times higher than was that of non-ECHO priority levels: DELTA and CHARLIE (17.05% vs. 0.37%). Asthmatics were associated with CA outcome (OR(95%CI): 0.60(0.47,0.77), p <0.001), but not with BI outcome.

CONCLUSIONS

The MPDS coding yielded a richer mix of severe outcomes in the higher priority levels.The Severe Respiratory Distress coding had the greatest number of patients and severe outcomes. Future studies that help refine the Severe Respiratory Distress code in the MPDS by more specific subgroups of patients would be beneficial.