Can a Software-Based Metronome Tool Enhance Compression Rate in a Realistic 911 Call Scenario Without Adversely Impacting Compression Depth for Dispatcher-Assisted CPR?

IntroductionImplementation of high-quality, dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) is critical to improving survival from out-of-hospital cardiac arrest (OHCA). However, despite some studies demonstrating the use of a metronome in a stand-alone setting, no research has yet demonstrated the effectiveness of a metronome tool in improving DA-CPR in the context of a realistic 911 call or using instructions that have been tested in real-world emergency calls.HypothesisUse of the metronome tool will increase the proportion of callers able to perform CPR within the target rate without affecting depth. METHODS: The prospective, randomized, controlled study involved simulated 911 cardiac arrest calls made by layperson-callers and handled by certified emergency medical dispatchers (EMDs) at four locations in Salt Lake City, Utah USA. Participants were randomized into two groups. In the experimental group, layperson-callers received CPR pre-arrival instructions with metronome assistance. In the control group, layperson-callers received only pre-arrival instructions. The primary outcome measures were correct compression rate (counts per minute [cpm]) and depth (mm). RESULTS: A total of 148 layperson-callers (57.4% assigned to experimental group) participated in the study. There was a statistically significant association between the number of participants who achieved the target compression rate and experimental study group (P=.003), and the experimental group had a significantly higher median compression rate than the control group (100 cpm and 89 cpm, respectively; P=.013). Overall, there was no significant correlation between compression rate and depth. CONCLUSION: An automated software metronome tool is effective in getting layperson-callers to achieve the target compression rate and compression depth in a realistic DA-CPR scenario.Scott G, Barron T, Gardett I, Broadbent M, Downs H, Devey L, Hinterman EJ, Clawson J, Olola C. Can a software-based metronome tool enhance compression rate in a realistic 911 call scenario without adversely impacting compression depth for dispatcher-assisted CPR? Prehosp Disaster Med. 2018;33(4):399-405.

Hospital-Confirmed Acute Myocardial Infarction: Prehospital Identification Using the Medical Priority Dispatch System.

Introduction Early recognition of an acute myocardial infarction (AMI) can increase the patient's likelihood of survival. As the first point of contact for patients accessing medical care through emergency services, emergency medical dispatchers (EMDs) represent the earliest potential identification point for AMIs. The objective of the study was to determine how AMI cases were coded and prioritized at the dispatch point, and also to describe the distribution of these cases by patient age and gender. Hypothesis/Problem No studies currently exist that describe the EMD's ability to correctly triage AMIs into Advanced Life Support (ALS) response tiers. METHODS: The retrospective descriptive study utilized data from three sources: emergency medical dispatch, Emergency Medical Services (EMS), and emergency departments (EDs)/hospitals. The primary outcome measure was the distributions of AMI cases, as categorized by Chief Complaint Protocol, dispatch priority code and level, and patient age and gender. The EMS and ED/hospital data came from the Utah Department of Health (UDoH), Salt Lake City, Utah. Dispatch data came from two emergency communication centers covering the entirety of Salt Lake City and Salt Lake County, Utah. RESULTS: Overall, 89.9% of all the AMIs (n=606) were coded in one of the three highest dispatch priority levels, all of which call for ALS response (called CHARLIE, DELTA, and ECHO in the studied system). The percentage of AMIs significantly increased for patients aged 35 years and older, and varied significantly by gender, dispatch level, and chief complaint. A total of 85.7% of all deaths occurred among patients aged 55 years and older, and 88.9% of the deaths were handled in the ALS-recommended priority levels. CONCLUSION: Acute myocardial infarctions may present as a variety of clinical symptoms, and the study findings demonstrated that more than one-half were identified as having chief complaints of Chest Pain or Breathing Problems at the dispatch point, followed by Sick Person and Unconscious/Fainting. The 35-year age cutoff for assignment to higher priority levels is strongly supported. The Falls and Sick Person Protocols offer opportunities to capture atypical AMI presentations. Clawson JJ , Gardett I , Scott G , Fivaz C , Barron T , Broadbent M , Olola C . Hospital-confirmed acute myocardial infarction: prehospital identification using the Medical Priority Dispatch System. Prehosp Disaster Med. 2018;33(1):29-35.

9-1-1 Triage of Non-Traumatic Chest Pain: Association with Hospital Diagnosis.

OBJECTIVE: Chest pain is one of the most common reasons people seek emergency care-and one of the most critical. In the United States, chest pain is the second most common reason for emergency department (ED) visits. A patient's primary complaint of "chest pain" may reflect a broad range of underlying causes; therefore, it is important that emergency medical service (EMS) agencies gain a thorough understanding of these cases, beginning with the initial management of chest pain in the 9-1-1 center. The primary objective of this study was to compare hospital-confirmed patient discharge diagnoses to all calls handled by emergency medical dispatchers (EMDs) using the Chest Pain/Chest Discomfort (Non-Traumatic) Chief Complaint Protocol. METHODS: The retrospective descriptive study utilized emergency medical dispatch, EMS, and hospital datasets, collected at two emergency communication centers in North America, from January 1, 2013 to December 31, 2014. Patients who were dispatched using the Chest Pain/Chest Discomfort Chief Complaint Protocol and matched to hospital datasets were included. The primary outcome was the number and percentage of cases classified as ischemic heart disease (IHD), other cardiac-related conditions, or non-cardiac-related conditions associated with chest pain. We also evaluated the distribution of causes of chest pain across demographic indicators and dispatch determinants. RESULTS: 3,007 cases were identified as "chest pain" at dispatch for which corresponding hospital records were identified. Cases in the study were obtained by linking EMS/Hospital and Emergency Medical Dispatch datasets. Of these cases, 47.1% (n = 1,417) were due to cardiac-related causes of chest pain, 61.5% of which were Ischemic Heart Disease (IHD), while the rest had other cardiac-related causes. Of the IHDs, 32.1% were Acute Myocardial Infarction (AMI). CONCLUSIONS: Underlying causes of non-traumatic chest pain reported to 9-1-1 demonstrate a wide range of etiologies, with a mix similar to that of chest pain patients in several other healthcare settings, including hospital emergency departments. Most IHD events are triaged by EMDs to the (highest) DELTA priority level, while the CHARLIE level captures nearly all of the remaining IHD cases.

Are two or four hands needed for elderly female bystanders to achieve the required chest compression depth during dispatcher-assisted CPR: a randomized controlled trial.

BACKGROUND: Rescuers are often unable to achieve the recommended 5-6 cm CC depth. The physical limitations of elderly bystanders may affect the quality of CC; thus, we investigated new strategies to improve CC performance. METHODS: We performed a randomized controlled trial in December 2013. Sixty-eight lay rescuers aged 50-75 were randomized to intervention or control pairs (males and females separately). Each pair performed 8 min of DA-CPR on a manikin connected to a PC. Each participant in every pair took turns performing CCs in cycles of 2 min and switched as advised by the dispatcher. In the middle of every 2-min cycle, the dispatcher asked the participants of the intervention group to perform the Andrew's manoeuvre (to push on the shoulders of the person while he/she performed CCs to achieve deeper CC). Data on the quality of the CCs were analysed for each participant and pair. RESULTS: The CC depth in the intervention group increased by 6.4 mm (p = 0.002) compared to the control group (54.2 vs. 47.8 mm) due to a significant difference in the female group. The CC depth in the female intervention and control groups was 51.5 and 44.9 mm. DISCUSSION: The largest group of out-of-hospital cardiac arrest occurred in males over the age of 60 at home, and accordingly, the most likely witness, if any, is the spouse or family member, most frequently an older woman. There is a growing body of evidence that female rescuers are frequently unable to achieve sufficient CC depth compared to male rescuers. In some instances, the adequate depth of the CCs could only be reached using four hands, with the second pair of hands placed on the shoulders of the rescuer performing CPR. CONCLUSION: Andrew's manoeuvre (four-hands CC) during the simulated DA-CPR significantly improved the performance of elderly female rescuers and helped them to achieve the recommended CC depth.

Outcome accuracy of the Emergency Medical Dispatcher's initial selection of a diabetic problems protocol.

INTRODUCTION: 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. OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Aspirin administration by emergency medical dispatchers using a protocol-driven aspirin diagnostic and instruction tool.

BACKGROUND: The American College of Cardiology and the American Heart Association recommend early aspirin administration to patients with symptoms of acute coronary syndrome (ACS)/acute myocardial infarction (AMI). The primary objective of this study was to determine if Emergency Medical Dispatchers (EMD) can provide chest pain/heart attack patients with standardised instructions effectively, using an aspirin diagnostic and instruction tool (ADxT) within the Medical Priority Dispatch System (MPDS) before arrival of an emergency response crew. METHODS: This retrospective study involved three dispatch centres in the UK and USA. We analysed 6 months of data involving chest pain/heart attack symptoms taken using the MPDS chest pain and heart problems/automated internal cardiac defibrillator protocols. RESULTS: The EMDs successfully completed the ADxT on 69.8% of the 44141 cases analysed. The patient's mean age was higher when the ADxT was completed, than when it was not (mean ± SD: 53.9 ± 19.9 and 49.9 ± 20.2; p<0.001, respectively). The ADxT completion rate was higher for second-party than first-party calls (70.3% and 69.0%; p=0.024, respectively). A higher percentage of male than female patients took aspirin (91.3% and 88.9%; p=0.001, respectively). Patients who took aspirin were significantly younger than those who did not (mean ± SD: 61.8 ± 17.5 and 64.7 ± 17.9, respectively). Unavailability of aspirin was the major reason (44.4%) why eligible patients did not take aspirin when advised. CONCLUSIONS: EMDs, using a standardised protocol, can enable early aspirin therapy to treat potential ACS/AMI prior to responders' arrival. Further research is required to assess reasons for not using the protocol, and the significance of the various associations discovered.

Medical Priority Dispatch System breathing problems protocol key question combinations are associated with patient acuity.

INTRODUCTION: The Breathing Problems Chief Complaint (CC) protocol in the Medical Priority Dispatch System (MPDS) was the system's most frequently used protocol. While "severe breathing problems" is a significant predictor of cardiac arrest (CA), previous data have demonstrated that the DELTA-level determinant codes in this CC contain patients across a wide spectrum of acuity. HYPOTHESIS: The hypothesis in this study was that certain combinations of caller answers to the breathing problems protocol key questions (KQs) are correlated with different but specific patient acuities. METHODS: This was a retrospective study conducted at one International Academies of Emergency Dispatch (IAED) Accredited Center of Excellence. Key Question combinations were generated and analyzed from 11 months of dispatch data, and extracted from MPDS software and the computer assisted dispatch system. Descriptive statistics were used to evaluate measures between study groups. RESULTS: Forty-two thousand cases were recorded; 52% of patients were female and the median age was 61 years. Overall, based on the original MPDS Protocol (before generating KQ combinations), patients with abnormal breathing and clammy conditions were the youngest. The MPDS DELTA-level constituted the highest percentage of cases (74.0%) and the difficulty speaking between breaths (DSBB) condition was the most prevalent (50.3%). Ineffective breathing and not alert conditions had the highest cardiac arrest quotient (CAQ). Based on the KQ combinations, the CA patients who also had the not alert condition were significantly older than other patients. The percentage of CA outcomes in asthmatic patients was significantly higher in DSBB plus not alert; DSBB plus not alert plus changing color; and DSBB plus not alert plus clammy conditions cases, compared to asthmatic abnormal breathing cases. CONCLUSIONS: The study findings demonstrated that MPDS KQ answer combinations relate to patient acuity. Cardiac arrest patients are significantly less likely to be asthmatic than those without CA, and vice versa. Using a prioritization scheme that accounts for the presence of either single or multiple signs and/or symptom combinations for the Breathing Problems CC protocol would be a more accurate method of assigning DELTA-level cases in the MPDS.