Amee Morgans

Sensitivity and Specificity of the Medical Priority Dispatch System in Detecting Cardiac Arrest Emergency Calls in Melbourne

INTRODUCTION In Australia, cardiac arrest kills 142 out of every 100,000 people each year; with only 3-4% of out-of-hospital patients with cardiac arrest in Melbourne surviving to hospital discharge. Prompt initiation of cardiopulmonary resuscitation (CPR), defibrillation, and advanced cardiac care greatly improves the chances of survival from cardiac arrest. A critical step in survival is identifying by the emergency ambulance dispatcher potential of the probability that the person is in cardiac arrest. The Melbourne Metropolitan Ambulance Service (MAS) uses the computerized call-taking system, Medical Priority Dispatch System (MPDS), to triage incoming, emergency, requests for ambulance responses. The MPDS is used in many emergency medical systems around the world, however, there is little published evidence of the systems efficacy. OBJECTIVE This study attempts to undertake a sensitivity/specificity analysis to determine the ability of MPDS to detect cardiac arrest. METHODS Emergency ambulance dispatch records of all cases identified as suspected cardiac arrest by MPDS were matched with ambulance, patient-care records and records from the Victorian Ambulance Cardiac Arrest Registry to determine the number of correctly identified cardiac arrests. Additionally, cases that had cardiac arrests, but were not identified correctly at the point of call-taking, were examined. All data were collected retrospectively for a three-month period (01 January through 31 March 2003). RESULTS The sensitivity of MPDS in detecting cardiac arrest was 76.7% (95% confidence interval (CI): 73.6%-79.8%) and specificity was 99.2% (95% CI: 99.1-99.3%). These results indicate that cardiac arrests are correctly identified in 76.7% of cases. CONCLUSION Although the system correctly identified 76.7% of cardiac arrest cases, the number of false negatives suggests that there is room for improvement in recognition by MPDS to maximize chances for survival in out-of-hospital cardiac arrest. This study provides an objective and comprehensive measurement of the accuracy of MPDS cardiac-arrest detection in Melbourne, as well as providing a baseline for comparison with subsequent changes to the MPDS.

Use of the Valsalva manoeuvre in the prehospital setting: a review of the literature.

Background: The Valsalva manoeuvre (VM) is used in the prehospital setting as a first-line treatment for managing haemodynamically stable supraventricular tachycardia (SVT) in the form of atrioventricular nodal re-entrant tachycardia (AVNRT) and atrioventricular re-entrant tachycardia (AVRT). The hospital-based use of this technique is supported by a number of published studies, but the performance and efficacy of the VM in the prehospital setting has not been examined. Methods: A review of the literature via electronic databases was conducted. Six clinical studies examining the technique and efficacy of the VM in arrhythmia reversion were identified. No prehospital studies were identified. Significant variation in the practical application of the VM and its efficacy was noted. Results: The literature identified three primary elements of the technique which affected its efficacy in reversion of SVT: a pressure of 40 mm Hg, the supine position and duration of 15 s. The efficacy of the VM in reversion of SVT is difficult to quantify in some literature owing to variations in technique and clinical application. The VM appears to be more successful than carotid sinus massage and ice-to-face techniques, and is inherently safe across all age groups. Conclusion: This review has shown that a standard of performance of the VM technique is defined within the medical literature, but no evidence exists to determine its efficacy or use in the prehospital setting. A prehospital study is therefore required to affirm the VM as part of prehospital clinical practice guidelines for SVT.

Drowning related out-of-hospital cardiac arrests: Characteristics and outcomes

AIM There are few studies on drowning-related out-of-hospital cardiac arrest (OHCA) in which patients are followed from the scene through to hospital discharge. This study aims to describe this population and their outcomes in the state of Victoria (Australia). METHODS The Victorian Ambulance Cardiac Arrest Registry was searched for all cases of OHCA with a precipitating event of drowning attended by emergency medical services (EMS) between October 1999 and December 2011. RESULTS EMS attended 336 drowning-related OHCA during the study period. Cases frequently occurred in summer (45%) and the majority of patients were male (70%) and adult (77%). EMS resuscitation was attempted on 154 (46%) patients. Of these patients, 41 (27%) survived to hospital arrival and 12 (8%) survived to hospital discharge (5 adults [6%] and 7 [12%] children). Few patients were found in a shockable rhythm (6%), with the majority presenting in asystole (79%) or pulse-less electrical activity (13%). An initial shockable rhythm was found to positively predict survival (AOR 48.70, 95% CI: 3.80-624.86) while increased EMS response time (AOR 0.73, 95% CI: 0.54-0.98) and salt water drowning (AOR 0.69, 95% CI: 0.01-0.84) were found to negatively predict survival. CONCLUSIONS Rates of survival in OHCA caused by drowning are comparable to other OHCA causes. Patients were more likely to survive if they did not drown in salt water, had a quick EMS response and they were found in a shockable rhythm. Prevention efforts and reducing EMS response time are likely to improve survival of drowning patients.

Involvement of emergency medical services at unplanned births before arrival to hospital: a structured review

Objective While infrequent, unplanned births before arrival (BBAs) are clinically significant events at which, conceivably, paramedics will be the first health professionals in attendance. This review aims to demonstrate that paramedics not only attend and transfer birthing women, but also use critical clinical and decision-making skills. It further proposes strategies that will support paramedics manage out-of-hospital obstetric emergencies. Design The bibliographic databases EMBASE, MEDLINE, CINAHL and Maternity and Infant Care were searched from 1991 to 2012 for relevant English language publications using key words and Medical Subject Heading (MeSH) terms. Data were extracted with respect to study design, incidence of BBAs, attendance of paramedics, complications and recommendations. Results Fourteen studies were selected for inclusion arising from the US, UK and Europe. While all studies acknowledged paramedics attend BBAs, seven reported the incidence of BBAs attended by paramedics, and two discuss issues specifically encountered by paramedics. Paramedics attended between 28.2% and 91.5% of all BBAs. While the articles reviewed noted that most of the births encountered by paramedics were uncomplicated, they all reported maternal or neonatal complications. Eight articles reported the most common maternal complication was excessive bleeding after birth, and nine reported the most frequent neonatal complication was hypothermia regardless of gestation. Conclusions Paramedics need to be adequately educated and equipped to manage BBAs at both undergraduate and graduate levels. Protocols should be developed between health and ambulance services to minimise risks associated with BBAs. A dearth of information surrounds the incidence of BBAs attended and the management performed by paramedics highlighting the need for further research.

Ethics in Evaluating a Sociotechnical Intervention With Socially Isolated Older Adults

The purpose of this article is to consider how ethical principles can inform the effective design and implementation of technology-based interventions that aim to promote the well-being of socially isolated older adults. We evaluated a new iPad application with small groups of older adults. In this article, we reflect on the ethical issues encountered at each stage of the research process. Drawing on the ethical principles of beneficence, research merit and integrity, justice, and respect, we identify key issues to consider in the future design and implementation of social isolation interventions that use new technologies. Key issues include (a) providing sufficient support to facilitate ongoing social interactions, (b) managing older adults’ expectations, (c) providing encouragement without coercion, and (d) responding to individual needs. We conclude that it is important to report on ethical challenges incurred when evaluating social isolation interventions to inform future research in this important area.

A novel approach for managing the growing demand for ambulance services by low-acuity patients

Objective The aim of the present study was to describe the Ambulance Victoria (AV) secondary telephone triage service, called the Referral Service (RS), for low-priority patients calling triple zero. This service provides alternatives to ambulance dispatch, such as doctor or nurse home visits. Methods A descriptive epidemiological review of all the cases managed between 2009 and 2012 was conducted, using data from AV case records, the Victorian Admitted Episodes Dataset and the Australian Bureau of Statistics. Cases were reviewed for patient demographics, condition, final disposition and RS outcome. Results In all, 107148 cases were included in the study, accounting for 10.3% of the total calls for ambulance attendance. Median patient age was 54 years and 55% were female. Geographically based socioeconomic status was associated with the rate of calls to the RS (r=-0.72; 95% confidence interval CI -0.104, -0.049; P<0.001). Abdominal pain and back symptoms were the most common patient problems. Although 68% of patients were referred to the emergency department, only 27.6% of the total cases were by emergency ambulance; the remainder were diverted to non-emergency ambulance or the patients own private transport. The remaining 32% of cases were referred to alternative service providers or given home care advice. Conclusions This paper describes the use of an ongoing secondary triage service, providing an effective strategy for managing emergency ambulance demand. What is known about the topic? Some calls to emergency services telephone numbers for ambulance assistance consist of cases deemed to be low-acuity that could potentially be better managed in the primary care setting. The demand on ambulance resources is increasing each year. Secondary telephone triage systems have been trialled in ambulance services in the US and UK with minimal success in terms of overall impact on ambulance resourcing. What does this paper add? This study describes a model of secondary telephone triage in the ambulance setting that has provided an effective way to divert patients to more suitable forms of health care to meet their needs. What are the implications for practitioners? The implications for practitioners are vast. Some of the issues that currently face paramedics include: fatigue because of high workloads; skills decay because of a lack of exposure to patients requiring intervention with skills the paramedics have, as well as a lack of time for paramedics to practice these skills during their downtime; and decreasing job satisfaction linked to both these factors. Implications for patients include quicker response times because more ambulances will be available to respond and increased patient safety because of decreased fatigue and higher skill levels in paramedics.

Time of Day and Day of Week Trends in EMS Demand

Abstract Objective. We examined temporal variations in overall Emergency Medical Services (EMS) demand, as well as medical and trauma cases separately. We analyzed cases according to time of day and day of week to determine whether population level demand demonstrates temporal patterns that will increase baseline knowledge for EMS planning. Methods. We conducted a secondary analysis of data from the Ambulance Victoria data warehouse covering the period 2008-2011. We included all cases of EMS attendance which resulted in 1,203,803 cases for review. Data elements comprised age, gender, date and time of call to the EMS emergency number along with the clinical condition of the patient. We employed Poisson regression to analyze case numbers and trigonometric regression to quantify distribution patterns. Results. EMS demand exhibited a bimodal distribution with the highest peak at 10:00 and a second smaller peak at 19:00. The highest number of cases occurred on Fridays, and the lowest on Tuesdays and Wednesdays. However, the distribution of cases throughout the day differed by day of week. Distribution patterns on Fridays, Saturdays and Sundays differed significantly from the rest of the week (p < 0.001). When categorized into medical or trauma cases, medical cases were more frequent during working hours and involved patients of higher mean age (57 years vs. 49 years for trauma, p < 0.001). Trauma cases peaked on Friday and Saturday nights around midnight. Conclusion. Day of week EMS demand distribution patterns reveal differences that can be masked in aggregate data. Day of week EMS demand distribution patterns showed not only which days have differences in demand but the times of day at which the demand changes. Patterns differed by case type as well. These differences in distribution are important for EMS demand planning. Increased understanding of EMS demand patterns is imperative in a climate of ever-increasing demand and fiscal constraints. Further research is needed into the effect of age and case type on EMS demand.

Secondary triage in prehospital emergency ambulance services: a systematic review

Objective Secondary telephone triage to divert low-acuity patients to alternative non-ambulance services before ambulance arrival has been trialled in the UK and USA as a management strategy to cope with the increase in ambulance demand. The objective of this systematic review was to examine the literature on the structure, safety and success of secondary triage systems. Methods For inclusion in the study, the telephone triage system had to be a secondary process, receiving referred patients who had already been categorised as low priority by a primary triage process. Two independent reviewers conducted the search to identify relevant studies. Six articles and one report were identified. Results The major theme of the papers was the safety and accuracy of secondary telephone triage in identifying low-acuity patients. Two studies also discussed patient satisfaction. There was a low incidence of adverse events, as expected as these patients had already been subjected to primary telephone triage. In the studies identifying ambulance dispatch as a potential final disposition, at least half of the patients were diverted away from ambulance dispatch. In the studies that identified self/home care as a final disposition, a maximum of 31% of patients were categorised to this outcome. Otherwise all patients were recommended for assessment by a healthcare professional other than ambulance clinicians. Patients appeared to be satisfied with secondary telephone triage on follow-up. Conclusions These results suggest that, while secondary triage of these patients is safe, further research is required to determine its most appropriate structure and its effect on ambulance demand.

Utilisation of emergency medical services for severe hypoglycaemia: An unrecognised health care burden

AIMS Diabetes is associated with several acute, life-threatening complications yet there are limited data on the utilisation of prehospital services for their management. This study aimed to examine the utilisation of emergency medical services (EMS) for prehospital hypoglycaemia, including patient characteristics and factors related to hospital transportation. METHODS An observational study of patients requiring EMS for hypoglycaemia across Victoria, Australia over three years was conducted. Pre-specified data including patient demographics, comorbidities, examination findings and transport outcomes were obtained. Logistic regression was used to assess factors associated with transportation. RESULTS During the study period, 12,411 hypoglycaemia events were attended by paramedics for people with diabetes. The majority were individuals with type 1 diabetes (58.8%), followed by type 2 diabetes (35.2%) and unspecified diabetes type (5.9%). Thirty-eight percent of patients were transported to hospital by EMS following hypoglycaemia. Factors associated with transport by EMS included extremes of age (<15 and >75years), female gender, type 2 diabetes, event at a nursing home or hospital/community clinic, presence of comorbidities and time of day. CONCLUSIONS Examination of the utilisation of EMS for hypoglycaemia has identified a previously unquantified need for emergency care for people with diabetes as well as factors related to hospital transportation.

Improving the coding and classification of ambulance data through the application of International Classification of Disease 10th revision

OBJECTIVES This paper aims to examine whether an adaptation of the International Classification of Disease (ICD) coding system can be applied retrospectively to final paramedic assessment data in an ambulance dataset with a view to developing more fine-grained, clinically relevant case definitions than are available through point-of-call data. METHODS Over 1.2 million case records were extracted from the Ambulance Victoria data warehouse. Data fields included dispatch code, cause (CN) and final primary assessment (FPA). Each FPA was converted to an ICD-10-AM code using word matching or best fit. ICD-10-AM codes were then converted into Major Diagnostic Categories (MDC). CN was aligned with the ICD-10-AM codes for external cause of morbidity and mortality. RESULTS The most accurate results were obtained when ICD-10-AM codes were assigned using information from both FPA and CN. Comparison of cases coded as unconscious at point-of-call with the associated paramedic assessment highlighted the extra clinical detail obtained when paramedic assessment data are used. CONCLUSIONS Ambulance paramedic assessment data can be aligned with ICD-10-AM and MDC with relative ease, allowing retrospective coding of large datasets. Coding of ambulance data using ICD-10-AM allows for comparison of not only ambulance service users but also with other population groups. WHAT IS KNOWN ABOUT THE TOPIC? There is no reliable and standard coding and categorising system for paramedic assessment data contained in ambulance service databases. WHAT DOES THIS PAPER ADD? This study demonstrates that ambulance paramedic assessment data can be aligned with ICD-10-AM and MDC with relative ease, allowing retrospective coding of large datasets. Representation of ambulance case types using ICD-10-AM-coded information obtained after paramedic assessment is more fine grained and clinically relevant than point-of-call data, which uses caller information before ambulance attendance. WHAT ARE THE IMPLICATIONS FOR PRACTITIONERS? This paper describes a model of coding using an internationally recognised standard coding and categorising system to support analysis of paramedic assessment. Ambulance data coded using ICD-10-AM allows for reliable reporting and comparison within the prehospital setting and across the healthcare industry.