Medical Priority Dispatch System Research Articles

Association between ambulance dispatch priority and patient condition.

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

Predictive Ability of an Emergency Medical Dispatch Stroke Diagnostic Tool in Identifying Hospital-Confirmed Strokes

Early hospital notification of a possible stroke arriving via emergency medical services (EMS) can prepare stroke center personnel for timely treatment, especially timely administration of tissue plasminogen activator. Stroke center notification from the emergency dispatch center-before responders reach the scene-may promote even earlier and faster system activation, meaning that stroke center teams may be ready to receive patients as soon as the ambulance arrives. This study evaluates the use of a Medical Priority Dispatch System (MPDS; Priority Dispatch Corp., Salt Lake City, UT) Stroke Diagnostic Tool (SDxT) to identify possible strokes early by comparing the tools' results to on-scene and hospital findings. The retrospective descriptive study utilized stroke data from 3 sources: emergency medical dispatch, EMS, and emergency department/hospital. A total of 830 cases were collected between June 2012 and December 2013, of which 603 (72.7%) had matching dispatch records. Of the 603 cases, 304 (50.4%) were handled using MPDS Stroke Protocol 28. The SDxT had an 86.4% ability (OR [95% CI]: 2.3 [1.5, 3.5]) to effectively identify strokes among all the hospital-confirmed stroke cases (sensitivity), and a 26.6% ability to effectively identify nonstrokes among all the hospital-confirmed nonstroke cases (specificity). The SDxT demonstrated a very high sensitivity, compared to similar tools used in the field and at dispatch. The specificity was somewhat low, but this was expected-and is intended in the creation of protocols to be used over the phone in emergency situations. The tool is a valuable method for identifying strokes early and may allow early hospital notification.

Abstract WMP70: Accuracy of Emergency Dispatcher Stroke Recognition When Employing a Stroke Screening Tool: A Systematic Review

Introduction: Emergency dispatchers are usually the first contact point for stroke patients accessing the healthcare system. Dispatcher stroke recognition is associated with better paramedic stroke recognition and faster emergency medical services (EMS) response time, but stroke is often unrecognized during the initial call. We conducted a systematic review to quantify the accuracy of emergency dispatcher stroke recognition when employing stroke screening tools. Methods: We conducted a comprehensive search Medline, EMBASE, CINAHL, and Cochrane databases to identify studies of dispatcher stroke recognition accuracy using a stroke screening tools such as the Medical Priority Dispatch System (MDPS) or Face Arm Speech Time (FAST) mnemonic. Studies were included if they reported dispatcher sensitivity or positive predictive value (PVP) using hospital stroke/TIA diagnosis as the gold standard. Study quality was assessed using QUADAS 2. Two independent reviewers determined study eligibility, assessed quality, and abstracted data. Results: We identified 1450 abstracts; seven cohort studies met inclusion criteria. Stroke screening tools included MPDS (n=4), FAST (n=2), and a novel screening algorithm (n=1). The sensitivity of dispatcher stroke recognition (5 studies, range 41-83%) and PPV (7 studies, range 42% -68%) were variable. Specificity was high (3 studies, 95-99%). No screening tool demonstrated superiority. Included studies had moderate risk of bias and dramatically variable stroke prevalence (range 3-68%). Conclusion: Published reports of screening tools utilized by emergency dispatchers demonstrate suboptimal sensitivity and PPV. More research is needed to identify the causes of poor dispatcher stroke recognition and to improve stroke screening tools.

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.

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. 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). 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. 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. 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.

Changes and trends of pre-hospital emergency disease spectrum in Beijing in the past decade (from 2003 to 2012)

Backgrounds: Pre-hospital emergency call is a crucial index to indicate emergency disease spectrum. For Beijing, which has changed greatly in economy and population, analyzing the trend of the emergency disease spectrum can greatly contribute to formulate the pre-hospital emergency planning. Methods: In this 10-year retrospective study, pre-hospital emergency records of Beijing Emergency Medical Center from 2003 to 2012 were collected. Medical Priority Dispatch System was used to classify the call demands. Linear regression models were constructed to examine the changing trends. Results: 2,410,575 cases were collected, and 2,278,415 of them were analyzed in this study. The results showed that: 1. In the past decade, the number of pre-hospital emergency call demands soared from 150,656 to 309,297 (204.6%, 2012/ 2003, p<0.001). 2. The top five call demands based on the rank of proportion were trauma related demands(25.4%, including falls（5.0%）, traffic/ transportation incidents(7.2%) and traumatic injuries(13.1%)), sick person(17.7%), heart problems(11.4%), unconscious/fainting（10.0%） and breathing problems（8.1%）Also, they were the top five fastest growing call demands. Conclusion: Compared with the growth of population (145.4%, 2012/2003), pre-hospital emergency calls increased much more, which shows a growing desire on ambulance service. Different from developed countries, the proportion of trauma related cases was constantly in the top rank and continuously increasing, much higher than that in San Francisco (15.7%), which could be resulted from accelerated city construction and rapid augment of vehicle quantity(244.8%, 2012/ 2003). Based on the changes and trends of pre-hospital emergency disease spectrum, it is encouraged to provide specific training program for emergency medical service staff and improve related medical devices. Note: Beijing emergency medical center is the only pre-hospital emergency system of Beijing government

Changes and trends of pre-hospital emergency disease spectrum in Beijing in 2003–12: a retrospective study

BackgroundPre-hospital emergency call is a crucial indicator of emergency disease spectrum. Since Beijing has changed substantially in economy and population, analysis of the trend of the emergency disease spectrum can greatly contribute to pre-hospital emergency planning. MethodsIn this 10-year retrospective study, pre-hospital emergency records of Beijing Emergency Medical Center, the only pre-hospital emergency system of Beijing Government, in 2003–12 were collected. Medical Priority Dispatch System was used to classify the call demands. Linear regression models were used to examine the trends. This study was exempt from ethical approval. Findings2 410 575 cases were collected. Non-pre-hospital requests, which were identified when the crew arrived, were excluded. Uncompleted and unidentified cases were further excluded, and 2 278 415 cases (94·5%) were included in the analysis. The number of pre-hospital emergency call demands soared from 150 656 in 2003 to 309 297 in 2012 (205·3%; p=0·158). The top five call demands throughout the decade were trauma-related demands (25·4%, including falls [5·0%], traffic or transportation incidents [7·2%], and traumatic injuries [13·1%]), general injuries (17·7%), heart problems (11·4%), unconsciousness or fainting (10·0%), and breathing problems (8·1%). These were also the top five fastest growing call demands. InterpretationCompared with the population growth in 2003–12 (145·4%), pre-hospital emergency calls increased much more, which shows a growing demand for ambulance service. By contrast with cities in developed countries, the proportion of trauma-related cases was constantly the highest among call demands, much higher than that in San Francisco (15·7%) in 2009, and is continuously increasing. This could be a result of accelerated city construction and rapid rise in vehicle quantity (244·8%). On the basis of the changes and trends of pre-hospital emergency disease spectrum, specific training programmes for emergency medical service staff and improvement in related medical devices are recommended. FundingResearch Special Fund for Public Welfare Industry of Health from the National Health and Family Planning Commission of China.

Time to identify cardiac arrest and provide dispatch-assisted cardio-pulmonary resuscitation in a criteria-based dispatch system.

Dispatch-assisted cardiopulmonary resuscitation (DA-CPR) plays a key role in out-of-hospital cardiac arrests. We sought to measure dispatchers' performances in a criteria-based system in recognizing cardiac arrest and delivering DA-CPR. Our secondary purpose was to identify the factors that hampered dispatchers' identification of cardiac arrests, the factors that prevented them from proposing DA-CPR, and the factors that prevented bystanders from performing CPR. We reviewed dispatch recordings for 1254 out-of-hospital cardiac arrests occurring between January 1, 2011 and December 31, 2013. Dispatchers correctly identified cardiac arrests in 71% of the reviewed cases and 84% of the cases in which they were able to assess for patient consciousness and breathing. The median time to recognition of the arrest was 60s. The median time to start chest compression was 220s. This study demonstrates that performances from a criteria-based dispatch system can be similar to those from a medical-priority dispatch system regarding out-of-hospital cardiac arrest (OHCA) time recognition and DA-CPR delivery. Agonal breathing recognition remains the weakest link in this sensitive task in both systems. It is of prime importance that all dispatch centers tend not only to implement DA-CPR but also to have tools to help them reach this objective, as today it should be mandatory to offer this service to the community. In order to improve benchmarking opportunities, we completed previously proposed performance standards as propositions.

The role of the emergency medical dispatch centre (EMDC) and prehospital emergency care safety: results from an incident report (IR) system.

The role of the emergency medical dispatch centre (EMDC) is essential to ensure coordinated and safe prehospital care. The aim of this study was to implement an incident report (IR) system in prehospital emergency care management with a view to detecting errors occurring in this setting and guiding the implementation of safety improvement initiatives. An ad hoc IR form for the prehospital setting was developed and implemented within the EMDC of Verona. The form included six phases (from the emergency call to hospital admission) with the relevant list of potential error modes (30 items). This descriptive observational study considered the results from 268 consecutive days between February and November 2010. During the study period, 161 error modes were detected. The majority of these errors occurred in the resource allocation and timing phase (34.2%) and in the dispatch phase (31.0%). Most of the errors were due to human factors (77.6%), and almost half of them were classified as either moderate (27.9%) or severe (19.9%). These results guided the implementation of specific corrective actions, such as the adoption of a more efficient Medical Priority Dispatch System and the development of educational initiatives targeted at both EMDC staff and the population. Despite the intrinsic limits of IR methodology, results suggest how the implementation of an IR system dedicated to the emergency prehospital setting can act as a major driver for the development of a "learning organization" and improve both efficacy and safety of first aid care.

How effectively can young people perform dispatcher-instructed cardiopulmonary resuscitation without training?

AimsSurvival from out-of-hospital cardiac arrest is increased by bystander cardiopulmonary resuscitation (CPR). Bystander performance can be improved when CPR instructions are delivered by a calltaker at the Emergency Communications Centre. Little is known about a young person's ability to understand these instructions and perform CPR correctly. We assessed the ability of a group of untrained young people to effectively apply these directions to an adult resuscitation manikin. Methods87 youngsters aged 7–15 years with no previous training in CPR were separately equipped with a mobile phone and an adult assessment manikin. They phoned the emergency number (111) and were automatically diverted to a senior emergency medical dispatcher (EMD). The EMD delivered resuscitation instructions which complied fully with Medical Priority Dispatch System (version 12.1). Performance was monitored using a Laerdal Computerised Skill Reporting System. ResultsAverage compression depth increased with age from 10.3mm to 30mm for 8 and 15 year olds respectively. 100 compressions per minute was achieved in youngsters aged 10 years and older but the rate fatigued over time and improved after interruption for two ventilations. Those aged 11 years and older consistently compressed the chest from 31mm to 50mm. Only one participant could successfully ventilate the manikin by mouth-to-mouth. ConclusionThis study demonstrates that untrained youngsters should perform compression-only CPR. From 11 years of age, they can effectively perform dispatcher-directed CPR by compressing the chest at an appropriate rate and depth. However, their technique benefits from formal training.

Outcome accuracy of the Emergency Medical Dispatcher's initial selection of a Diabetic Problems protocol

Introduction: Diabetes mellitus can cause acute, sudden symptoms requiring emergency intervention. Emergency medical dispatchers (EMDs) must identify true diabetic complaints in order to determine the correct care. In 911 systems utilizing the Medical Priority Dispatch System (MPDS), EMDs determine a patient's chief complaint by matching the caller's response to an initial prescripted question to the appropriate chief complaint.

Ability of a diabetic problems protocol to predict patient severity indicators determined by on-scene EMS crews

Purpose: Diabetes mellitus is a leading cause of human disease, with 25.8 million Americans affected. Diabetes can cause chronic or sudden signs and symptoms, which often result in observers calling 911 for assistance. The Emergency Dispatcher's Interpretation of these calls affects dispatch triage and pre-arrival patient care. The purpose of this study is to determine the relationship between the EMDs’ assigned Medical Priority Dispatch System (MPDS) determinant codes and patient severity indicators as determined by paramedic (or EMT) on-scene findings and treatments.

Analysis of Emergency Medical Services Triage and Dispatch Errors by Registered Nurses in Italy

IntroductionThe major elements of an effective emergency medical services (EMS) system include a single telephone access number, accurate assessment of the urgency of the health problem, and timely dispatch of appropriate personnel and equipment. In Italy, EMS calls are managed by emergency operations centers by registered nurses who have received specialized education in this function. The nurses determine the criticality of the situations and assign an EMS response priority level identified by a color code, ranging from red (very critical) to green (not critical). At times, the severity of a situation may be underestimated, resulting in assignment of a lower EMS response priority and the potential for patient death (code black). The purpose of this study was to analyze factors associated with registered nurse under-triage of EMS calls subsequently found to be associated with deaths, termed “green-black code” cases. MethodsWe carried out a retrospective qualitative analysis of EMS telephone conversations using Fele’s conversation analysis method. The characteristics of green-black code calls were compared with the characteristics of the population of all EMS calls during the study period. ResultsThe study patients were older, with a mean age of 81.6 years. The callers were individuals calling on behalf of the patients, rather than the patients themselves. The callers reported symptoms that were not life-threatening. Nurse operators did not always inquire about the patients’ vital signs as required by the Medical Priority Dispatch System protocol. The phone conversations were shorter than normal (54.26 seconds vs 65 seconds). DiscussionAlthough the importance of dispatch system protocols is wellknown, it is also important that nurse triage operators have proper training to ensure that major parameters such as vital signs and symptomatology are obtained and to reduce caller stress level.

Outcome Accuracy of the Emergency Medical Dispatcher's Initial Selection of a Diabetic Problems Protocol

Diabetes mellitus, although a chronic disease, also can cause acute, sudden symptoms requiring emergency intervention. In these cases, Emergency Medical Dispatchers (EMDs) must identify true diabetic complaints in order to determine the correct care. In 911 systems utilizing the Medical Priority Dispatch System (MPDS), International Academies of Emergency Dispatch-certified EMDs determine a patient's chief complaint by matching the caller's response to an initial pre-scripted question to one of 37 possible chief complaints protocols. The ability of EMDs to identify true diabetic-triggered events reported through 911 has not been studied. The primary objective of this study was to determine the percentage of EMD-recorded patient cases (using the Diabetic Problems protocol in the MPDS) that were confirmed by either attending paramedics or the hospital as experiencing a diabetic-triggered event. This was a retrospective study involving six hospitals, one fire department, and one ambulance service in Salt Lake City, Utah USA. Dispatch data for one year recorded under the Diabetic Problems protocol, along with the associated paramedic and hospital outcome data, were reviewed/analyzed. The outcome measures were: the percentage of cases that had diabetic history, percentage of EMD-identified diabetic problems cases that were confirmed by Emergency Medical Services (EMS) and/or hospital records as true diabetic-triggered events, and percentage of EMD-identified diabetic patients who also had other medical conditions. A diabetic-triggered event was defined as one in which the patient's emergency was directly caused by diabetes or its medical management. Descriptive statistics were used for categorical measures and parametric statistical methods assessed the differences between study groups, for continuous measures. Three-hundred ninety-three patient cases were assigned to the Diabetic Problems Chief Complaint protocol. Of the 367 (93.4%) patients who had a documented history of diabetes, 279 (76%) were determined to have had a diabetic-triggered event. However, only 12 (3.6%) initially assigned to this protocol did not have a confirmed history of diabetes. Using the MPDS to select the Diabetic Problems Chief Complaint protocol, the EMDs correctly identified a true diabetic-triggered event the majority of the time. However, many patients had other medical conditions, which complicated the initial classification of true diabetic-triggered events. Future studies should examine the associations between the five specific Diabetic Problems Chief Complaint protocol determinant codes (triage priority levels) and severity measures, eg, blood sugar level and Glasgow Coma Score.

“Push as Hard as You Can” Instruction for Telephone Cardiopulmonary Resuscitation: A Randomized Simulation Study

BackgroundThe medical priority dispatch system (MPDS®) assists lay rescuers in protocol-driven telephone-assisted cardiopulmonary resuscitation (CPR). ObjectiveOur aim was to clarify which CPR instruction leads to sufficient compression depth. MethodsThis was an investigator-blinded, randomized, parallel group, simulation study to investigate 10 min of chest compressions after the instruction “push down firmly 5 cm” vs. “push as hard as you can.” Primary outcome was defined as compression depth. Secondary outcomes were participants exertion measured by Borg scale, provider's systolic and diastolic blood pressure, and quality values measured by the skill-reporting program of the Resusci® Anne Simulator manikin. For the analysis of the primary outcome, we used a linear random intercept model to allow for the repeated measurements with the intervention as a covariate. ResultsThirteen participants were allocated to control and intervention. One participant (intervention) dropped out after min 7 because of exhaustion. Primary outcome showed a mean compression depth of 44.1 mm, with an inter-individual standard deviation (SDb) of 13.0 mm and an intra-individual standard deviation (SDw) of 6.7 mm for the control group vs. 46.1 mm and a SDb of 9.0 mm and SDw of 10.3 mm for the intervention group (difference: 1.9; 95% confidence interval −6.9 to 10.8; p = 0.66). Secondary outcomes showed no difference for exhaustion and CPR-quality values. ConclusionsThere is no difference in compression depth, quality of CPR, or physical strain on lay rescuers using the initial instruction “push as hard as you can” vs. the standard MPDS® instruction “push down firmly 5 cm.”

Implementation of the ALERT algorithm, a new dispatcher-assisted telephone cardiopulmonary resuscitation protocol, in non-Advanced Medical Priority Dispatch System (AMPDS) Emergency Medical Services centres

ObjectivesEarly bystander cardiopulmonary resuscitation (CPR) is a key factor in improving survival from out-of-hospital cardiac arrest (OHCA). The ALERT (Algorithme Liégeois d’Encadrement à la Réanimation par Téléphone) algorithm has the potential to help bystanders initiate CPR. This study evaluates the effectiveness of the implementation of this protocol in a non-Advanced Medical Priority Dispatch System area. MethodsWe designed a before and after study based on a 3-month retrospective assessment of victims of OHCA in 2009, before the implementation of the ALERT protocol in Liege emergency medical communication centre (EMCC), and the prospective evaluation of the same 3 months in 2011, immediately after the implementation. ResultsAt the moment of the call, dispatchers were able to identify 233 OHCA in the first period and 235 in the second. Victims were predominantly male (59%, both periods), with mean ages of 64.1 and 63.9 years, respectively. In 2009, only 9.9% victims benefited from bystander CPR, this increased to 22.5% in 2011 (p<0.0002). The main reasons for protocol under-utilisation were: assistance not offered by the dispatcher (42.3%), caller physically remote from the victim (20.6%). Median time from call to first compression, defined here as no flow time, was 253s in 2009 and 168s in 2011 (NS). Ten victims were admitted to hospital after ROSC in 2009 and 13 in 2011 (p=0.09). ConclusionFrom the beginning and despite its under-utilisation, the ALERT protocol significantly improved the number of patients in whom bystander CPR was attempted.

Mobile phones video CPR: Preliminary results in a non-Advanced Medical Priority Dispatch System (AMPDS) Emergency Medical Services centres

Objectives: For several years, mobile phones offer the opportunity to transmit images and video via 3G network. Videoconference between lay rescuers of cardiac arrest and 112 dispatchers may offer interesting perspectives in the field of dispatching-assisted cardiopulmonary resuscitation (CPR). This study investigates the impact of videoconference on CPR performances.

ALERT protocol: Efficiency of an e-learning training in a non-Advanced Medical Priority Dispatch System (AMPDS) Emergency Medical Services centres

ALERT protocol: Efficiency of an e-learning training in a non-Advanced Medical Priority Dispatch System (AMPDS) Emergency Medical Services centres

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.

Dispatch-assisted CPR: Where are the hold-ups during calls to emergency dispatchers? A preliminary analysis of caller–dispatcher interactions during out-of-hospital cardiac arrest using a novel call transcription technique

BackgroundSurvival from out-of-hospital cardiac arrest (OHCA) is dependent on the chain of survival. Early recognition of cardiac arrest and provision of bystander cardiopulmonary resuscitation (CPR) are key determinants of OHCA survival. Emergency medical dispatchers play a key role in cardiac arrest recognition and giving telephone CPR advice. The interaction between caller and dispatcher can influence the time to bystander CPR and quality of resuscitation. We sought to pilot the use of emergency call transcription to audit and evaluate the holdups in performing dispatch-assisted CPR. MethodsA retrospective case selection of 50 consecutive suspected OHCA was performed. Audio recordings of calls were downloaded from the emergency medical dispatch centre computer database. All calls were transcribed using proprietary software and voice dialogue was compared with the corresponding stage on the Medical Priority Dispatch System (MPDS). Time to progress through each stage and number of caller–dispatcher interactions were calculated. ResultsOf the 50 downloaded calls, 47 were confirmed cases of OHCA. Call transcription was successfully completed for all OHCA calls. Bystander CPR was performed in 39 (83%) of these. In the remaining cases, the caller decided the patient was beyond help (n=7) or the caller said that they were physically unable to perform CPR (n=1). MPDS stages varied substantially in time to completion. Stage 9 (determining if the patient is breathing through airway instructions) took the longest time to complete (median=59s, IQR 22–82s). Stage 11 (giving CPR instructions) also took a relatively longer time to complete compared to the other stages (median=46s, IQR 37–75s). Stage 5 (establishing the patient's age) took the shortest time to complete (median=5.5s, IQR 3–9s). ConclusionTranscription of OHCA emergency calls and caller–dispatcher interaction compared to MPDS stage is feasible. Confirming whether a patient is breathing and completing CPR instructions required the longest time and most interactions between caller and dispatcher. Use of call transcription has the potential to identify key factors in caller–dispatcher interaction that could improve time to CPR and further research is warranted in this area.

Implementation of Prehospital Dispatch Protocols That Triage Low-acuity Patients to Advice-line Nurses

Introduction. Although EMS agencies have been designed to efficiently provide medical assistance to individuals, the overuse of 9-1-1 as an alternative to primary medical care has resulted in the need for new methods to respond to this increasing demand. Our study analyzes the efficacy of classifying specific low-acuity calls that can be transferred to an advice-line nurse for further medical instruction. The objectives of our study were to analyze the impact of implementing this protocol and resultant patient feedback regarding the transfer to an advice-line nurse. Methods. We collected data for retrospective review from April 2011 to April 2012 from a single municipal EMS agency with an average annual call volume of approximately 90,000. Medical Priority Dispatch System response codes were assigned to calls based on patient acuity. Patients classified under Omega response codes were assessed for eligibility of transfer to nurse advice lines. Exclusion criteria included the following: if the call was placed by a third-party caller; if the patient refused to be transferred to the advice-line nurse; anytime the MPDS system was not used; if the patient was referred from a skilled nursing facility, school, or university nursing office, or physician's office. Telephone surveys were conducted for those patients who spoke to an advice-line nurse and did not receive an ambulance response 24 hours after calling 9-1-1 to obtain patient feedback. Results. The database included 1660 patients initially classified as Omega and eligible for transfer to an advice-line nurse. After applying the exclusion criteria, 329 (19.8%) patients were ultimately transferred to an advice-line nurse and 204 (12.3%) received no ambulance response. Of those patients who were not transported by ambulance 118 (57.8%), patients completed telephone follow-up, with 104 (88.1%) reporting the nontransport option met their health-care needs and 108 (91.5%) responding they would accept the transfer again for a similar complaint. Conclusion. We identified an average of two patients per day as eligible for transfer to the nurse advice line, with less than one patient successfully completing the Omega protocol per day. While impact was limited, there was a decrease in ambulance response.