Is there any room for shortening hands-off time further when using an AED?

Background

Automated external defibrillators (AEDs) play a very important role in out-of-hospital cardiopulmonary resuscitation (CPR). The mandatory hands-off time imposed by current AEDs is not short enough to bring about the full benefits of rapid defibrillation with an AED into light. The aim of this study is to examine whether a change in the process of charging the capacity and removing explanations from the prompts of the AEDs shortens hands-off time.

Methods

The operating steps and the voice prompts of the current AEDs were reviewed and the time intervals between the steps and the voice prompts were measured. We modified an AED to fully precharge the capacitor and to contain more concise voice prompts.

Results

We had 42 expert rescuers and 50 lay-person rescuers perform 2-rescuer CPR with the modified AED and the old AED, respectively. Using the modified AED significantly reduced hands-off times by 9.95 s (95% CI: 9.67–10.23) in 2-rescuer CPR and by 10.68 s (95% CI: 9.75–11.61) in 1-rescuer CPR (p < 0.001).

Conclusion

Full precharging of the capacitor and exclusion of explanations from the voice prompts of AEDs can shorten the hands-off time in both 1 and 2-rescuer CPR.     

Modeling the impact of public access defibrillator range on public location cardiac arrest coverage

Background

Public access defibrillation with automated external defibrillators (AEDs) can improve survival from out-of-hospital cardiac arrests (OHCA) occurring in public. Increasing the effective range of AEDs may improve coverage for public location OHCAs.

Objective

To quantify the relationship between AED effective range and public location cardiac arrest coverage.

Methods

This was a retrospective cohort study using the Resuscitation Outcomes Consortium Epistry database. We included all public-location, atraumatic, EMS-attended OHCAs in Toronto, Canada between December 16, 2005 and July 15, 2010. We ran a mathematical model for AED placement that maximizes coverage of historical public OHCAs given pre-specified values of AED effective range and the number of locations to place AEDs. Locations of all non-residential buildings were obtained from the City of Toronto and used as candidate sites for AED placement. Coverage was evaluated for range values from 10 to 300 m and number of AED locations from 10 to 200, both in increments of 10, for a total of 600 unique scenarios. Coverage from placing AEDs in all public buildings was also measured.

Results

There were 1310 public location OHCAs during the study period, with 25,851 non-residential buildings identified as candidate sites for AED placement. Cardiac arrest coverage increased with AED effective range, with improvements in coverage diminishing at higher ranges. For example, for a deployment of 200 AED locations, increasing effective range from 100 m to 200 m covered an additional 15% of cardiac arrests, whereas increasing range further from 200 m to 300 m covered an additional 10%. Placing an AED in each of the 25,851 public buildings resulted in coverage of 50% and 95% under assumed effective ranges of 50 m and 300 m, respectively.

Conclusion

Increasing AED effective range can improve cardiac arrest coverage. Mathematical models can help evaluate the potential impact of initiatives which increase AED range.     

Systematic downloading and analysis of data from automated external defibrillators used in out-of-hospital cardiac arrest

Background

Valuable information can be retrieved from automated external defibrillators (AEDs) used in victims of out-of-hospital cardiac arrest (OHCA). We describe our experience with systematic downloading of data from deployed AEDs. The primary aim was to compare the proportion of shockable rhythm from AEDs used by laypersons with the corresponding proportion recorded by the Emergency Medical Services (EMS) on arrival.

Methods

In a 20-month study, we collected data on OHCAs in the Capital Region of Denmark where an AED was deployed prior to arrival of EMS. The AEDs were brought to the emergency medical dispatch centre for data downloading and rhythm analysis. Patient data were retrieved from the medical records from the admitting hospital, whereas data on EMS rhythm analyses were obtained from the Danish Cardiac Arrest Register between 2001 and 2010.

Results

A total of 121 AEDs were deployed, of which 91 cases were OHCAs with presumed cardiac origin. The prevalence of initial shockable rhythm was 55.0% (95% CI [44.7–64.8%]). This was significantly greater than the proportion recorded by the EMS (27.6%, 95% CI [27.0–28.3%], p < 0.0001). Shockable arrests were significantly more likely to be witnessed (92% vs. 34%, p < 0.0001) and the bystander CPR rate was higher (98% vs. 85%, p = 0.04). More patients with initial shockable rhythm achieved return of spontaneous circulation upon hospital arrival (88% vs. 7%, p < 0.0001) and had higher 30-day survival rate (72% vs. 5%, p < 0.0001).

Conclusion

AEDs used by laypersons revealed a higher proportion of shockable rhythms compared to the EMS rhythm analyses.     

Junior physician skill and behaviour in resuscitation: A simulation study

Introduction

Physicians are expected to manage their role as teamleader during resuscitation. During inter-hospital transfer the physician has the highest medical credentials on a small team. The aim of this study was to describe physician behaviour as teamleaders in a simulated cardiac arrest during inter-hospital transfer. Our goal was to pinpoint deficits in knowledge and skill integration and make recommendations for improvements in education.

Method

An ambulance was the framework for the simulation; the scenario a patient with acute coronary syndrome suffering ventricular fibrillation during transportation. Physicians (graduation age ≤5 years) working in internal medicine departments in Denmark were studied. The ambulance crew was instructed to be passive to clarify the behaviour of the physicians.

Results

72 physicians were studied. Chest compressions were initiated in 71 cases, ventilation and defibrillation in 72. The median times for arrival of the driver in the patient cabin, initiation of ventilation and chest compressions, and first defibrillation were all less than 1 min. Medication was administered in 63/72 simulations (88%), after a median time of 210 s. Adrenaline was the preferred initial drug administered (58/63, 92%). Tasks delegated were ventilations, chest compressions, defibrillation, and administration of medication (97%, 92%, 42%, and 10% of cases, respectively).

Discussion and conclusion

Junior physicians performed well with respect to the treatment given and the delegation of tasks. However, variations in the time of initiation it took for each treatment indicated lack of leadership skills. It is imperative that the education of physicians includes training in leadership.     

Use of automated external defibrillators in patients with traumatic out-of-hospital cardiac arrest

Background

Because out-of-hospital cardiac arrests (OHCAs) due to a major trauma rarely present with shockable rhythms, the potential benefits of using automated external defibrillators (AEDs) at the scene of traumatic OHCAs have not been examined.

Methods

We conducted an observational, retrospective cohort study using an Utstein-style analysis in Tainan city, Taiwan. The enrollees were adult patients with traumatic OHCAs accessed by emergency medical technicians (EMTs) from January 1, 2004 to December 31, 2010. The exposure was the use or non-use of AEDs at the scene, as determined by the clinical judgment of the EMTs. The primary outcome evaluated was a sustained (≥2 h) return of spontaneous circulation (ROSC), and the secondary outcomes were prehospital ROSC, overall ROSC, survival to hospital admission, survival at one month and favorable neurologic status at one month.

Results

A total of 424 patients (313 males) were enrolled, of whom 280 had AEDs applied, and 144 did not. Only 25 (5.9%) patients had received bystander cardiopulmonary resuscitation (CPR), and merely 21 (7.5%) patients in the AED group presented with shockable rhythms. Compared to the non-AED group, the primary and secondary outcomes of the AED group were not significantly different, except for a significantly lower prehospital ROSC rate (1.1% vs 4.9%, p < 0.05). Multivariate analysis showed no significant interactions between the use of AEDs and other key variables. Use of the AED was not associated with sustained ROSC (OR 1.33; 95% CI 0.75–2.38, p = 0.33).

Conclusions

In a community with a low prevalence of shockable rhythms and administration of bystander CPR in patients with traumatic OHCA, we found no significant differences in the sustained ROSC between the AED and the non-AED groups. Considering scene safety and the possible interruption of CPR, we do not encourage the routine use of AEDs at the scene of traumatic OHCAs.     

EMTs and GPs: what do we think of each other?

Background

Ireland''s health services are undergoing dramatic reorganisation. The establishment of general practitioner (GP) out of hours cooperatives and the integration of current ambulance services into a national ambulance service are among the issues that will impact on prehospital care of emergencies. The study aimed to explore the perceptions of GPs and emergency medical technicians (EMTs) of their own and each other''s roles in the context of such reforms.

Methods

A census of all GPs (511) and EMTs (301) in three of Ireland''s eight health board regions was undertaken. A questionnaire containing 31 statements asked respondents to indicate their agreement (or lack of it) in areas such as general relationships, care, and training, roles in emergencies and future developments.

Results

Of the personnel contacted, 72% of GPs and 75% of EMTs responded. They report excellent working relationships, agree that the ambulance service is of high quality, and that GPs are willing to provide care in emergencies. However, working links are less satisfactory for EMTs, who report a far higher perception of GP use of emergency ambulances than reported by GPs. Both groups are interested in innovative future links.

Discussion

Convergence between the professional groups in different geographic areas and between the disciplines across the areas is striking. They include areas of satisfaction and dissatisfaction. The need for improved liaison between the disciplines is clear.     

Use and benefits of public access defibrillation in a nation-wide network

Background

Automated External Defibrillators (AEDs) are known to increase survival after out-of-hospital cardiac arrest (OHCA). The aim of this study was to examine the use and benefit of public-access defibrillation (PAD) in a nation-wide network. We primarily sought to assess survival at 1 month but information about the circumstances of each OHCA is provided as well.

Methods

In this 28-month study, we assessed the use of 807 AEDs in Denmark. When an AED was deployed information about the circumstances of OHCA, the bystander, the AED and the victim's condition was obtained.

Results

An AED was connected to an OHCA victim prior to the arrival of Emergency Medical Services (EMS) in 48 instances. Ten percent of bystanders were off-duty healthcare professionals. Shockable arrests (N = 31, 70%) were significantly more likely to be witnessed (94% vs. 54%) to occur at sports facilities (74% vs. 31%), in relation to exercise (42% vs. 0%), and with improved 30-day survival (69% vs. 15%, p = 0.001). Among those presenting with a shockable rhythm, 20 (65%) had Return of Spontaneous Circulation upon arrival of EMS and 8 (26%) were conscious, which emphasizes the diagnostic value of ECG downloads from AEDs. Survival could be determined in 42 of 44 patients with OHCA of cardiac origin, and was 52% (n = 22, 95% CI [38–67]) and the Cerebral Performance Category was 1 (Good Cerebral Performance) in all survivors.

Conclusion

With a 30-day neurologically intact survival of 69% for patients with shockable rhythms, this study provides further evidence of the lifesaving potential of PAD.     

Changing trends in the use of seizure prophylaxis after traumatic brain injury: A shift from phenytoin to levetiracetam

Purpose

Current guidelines for traumatic brain injury (TBI) recommend antiepileptic drugs (AEDs) for 7 days after injury to decrease posttraumatic seizure risk. Phenytoin decreases seizure risk 73% vs placebo during this time. Levetiracetam (LEV) is an alternative; however, no published data validate comparable efficacy. Our objective was to evaluate seizure incidence 7 days after TBI in patients treated with phenytoin (PHT) vs LEV and to characterize practice of AED selection.

Methods

A retrospective observational study was conducted using a Trauma Registry (Collector Trauma Registry; Digital Innovation, Inc, Forrest Hill, Md) to evaluate patients with TBI. Patients with an initial Head/Neck Abbreviated Injury Scale score of 3 or higher and a Glasgow Coma Scale of 8 or less were included.

Results

Of 109 patients, 89 received PHT, and 20, LEV. Two patients experienced posttraumatic seizure, 1 in each group. Sixty-eight patients survived to hospital discharge; 65% received prophylactic AED greater than 7 days. Ninety-eight percent of 81 patients admitted between 2000 and 2007 received PHT, whereas 64% of 28 patients admitted between 2008 and 2010 received LEV.

Conclusion

Only 2 patients experienced posttraumatic seizure after receiving AED, indicating low incidence. Most surviving to hospital discharge received AED prophylaxis greater than 7 days despite guideline recommendations. After approval of intravenous LEV, a trend favoring LEV was observed.     

First Responder for In-Hospital Resuscitation: 5-Year Experience with an Automated External Defibrillator-Based Program

Background

The survival of in-hospital cardiac arrest (8–25%) has not changed substantially in the past. Until now, most hospitals in Germany had no standardized protocols available for a course of action in case of emergency, and there are no continuous registry data for in-hospital cardiac arrest and survival.

Objective

Our aim was to improve survival and receive outcomes data, so we implemented a structured hospital-wide automated first-responder system in the hospital. Here our 5-year experience with 443 emergency calls is outlined.

Methods

Throughout the hospital, 15 automated external defibrillator (AED) “access spots,” which can be easily reached within 30 s, were identified. AEDs were then installed at these locations (Lifepak 500 and Lifepak 1000, Medtronic equipped with a Biolog 3000i portable ECG monitor). At the same time, a training program was initiated in which the employees of the hospital participated once a year. Participants learned how to apply and activate an AED in case of cardiac arrest even before the designated Cardiac Arrest Team arrived at the scene.

Results

A witnessed cardiac arrest event was confirmed in 126 cases. In 56 of the 126 cases, the primary arrest rhythm was either ventricular tachycardia or ventricular fibrillation and the AED delivered a shock. In this group, spontaneous circulation was reached in 44 cases (79%) and 23 patients (41%) were discharged. In 44% (24 from 55 patients) of the cases, a shock was recommended by AED and delivered by the first responders before the rescue team arrived.

Conclusions

The first-responder AED program successfully gave training lessons to the hospital staff. The training included how to initiate the cardiac arrest call, how to use the AED, and how to start immediate resuscitation. As a result, a higher survival rate after in-hospital cardiac arrest can be accomplished.     

Local lay rescuers with AEDs,alerted by text messages,contribute to early defibrillation in a Dutch out-of-hospital cardiac arrest dispatch system

Aim

Public access defibrillation rarely reaches out-of-hospital cardiac arrest (OHCA) patients in residential areas. We developed a text message (TM) alert system, dispatching local lay rescuers (TM-responders). We analyzed the functioning of this system, focusing on response times and early defibrillation in relation to other responders.

Methods

In July 2013, 14 112 TM-responders and 1550 automated external defibrillators (AEDs) were registered in a database residing with the dispatch center of two regions of the Netherlands. TM-responders living <1000 m radius of the patient received a TM to go to the patient directly, or were directed to retrieve an AED first. We analyzed 1536 OHCA patients where a defibrillator was connected from February 2010 until July 2013. Electrocardiograms from all defibrillators were analyzed for connection and defibrillation time.

Results

Of all OHCAs, the dispatcher activated the TM-alert system 893 times (58.1%). In 850 cases ≥1 TM-responder received a TM-alert and in 738 cases ≥1 AED was available. A TM-responder AED was connected in 184 of all OHCAs (12.0%), corresponding with 23.1% of all connected AEDs. Of all used TM-responder AEDs, 87.5% were used in residential areas, compared to 71.6% of all other defibrillators. TM-responders with AEDs defibrillated mean 2:39 (min:sec) earlier compared to emergency medical services (median interval 8:00 [25–75th percentile, 6:35–9:49] vs. 10:39 [25–75th percentile, 8:18–13:23], P < 0.001). Of all shocking TM-responder AEDs, 10.5% delivered a shock ≤6 min after call.

Conclusion

A TM-alert system that includes local lay rescuers and AEDs contributes to earlier defibrillation in OHCA, particularly in residential areas.     

The Los Angeles public access defibrillator (PAD) program: Ten years after

Background

Public access automated external defibrillator (PAD) programs have been shown to be successful in several municipalities. This study sought to determine the usage of and survival rate from a large, urban PAD program in the first 10 years since its implementation.

Methods

This was a prospective, longitudinal, observational study from January 2002–2012 conducted in Los Angeles, California, a city with a population of 3.8 million. An incremental rollout resulted in a current total of 1300 automated external defibrillators (AEDs) in place in city-owned buildings and other public places, including all 3 area airports, golf-courses, and public pools. All instances where an AED was applied were included in the study.

Results

There were 59 incidents of cardiac arrest with a public access AED applied, of which 42 (71%) occurred at an airport. 51 (86%) of the patients were male, with a median age of 64 years (interquartile range, 56.5 to 70 years). A shockable rhythm was detected and shocks were applied in 39 (66%) patients, with 30 (77%) of these patients achieving a return of spontaneous circulation (ROSC). Of those patients who received shock(s) by public access AED, 27 (69%) survived to hospital discharge. The youngest survivors were a 25 year old male and a 34 year old female.

Conclusion

While the majority of PAD cases occurred at an airport, there were also survivors from other public locations. AEDs deployed as part of a large PAD program resulted in a very high survival rate for patients with cardiac arrest.     

Use of phenytoin for the long-term treatment of partial seizures: Results of a survey conducted during the 2004 meeting of the American Academy of Neurology

Background:

Epilepsy is a chronic disorder that typically requires lifelongpharmacologic treatment. The choice of an antiepileptic drug (AED), therefore, requires careful consideration of efficacy and tolerability. However, the majority of patients with new-onset seizures are initially treated by physicians in the emergency department (ED) or by non-ED physicians (primary care physicians or internists), with phenytoin being the most common AED prescribed for initial therapy, and the long-term adverse effects of AEDs are often overlooked.

Objective:

The aim of this survey was to examine the perspectives of neurologistsand epileptologists concerning initial therapies prescribed by ED physicians and non-ED physicians for newly diagnosed partial seizures, particularly phenytoin, and the suitability of these therapies for long-term management of the disease.

Methods:

A computerized survey was conducted during the 2004 AmericanAcademy of Neurology meeting. The survey consisted of 10 questions concerning the use of AEDs in the initial and long-term treatment of newly diagnosed partial seizures.

Results:

The responses of 268 practitioners were analyzed. Survey participants indicated that 71% of patients referred to them by ED physicians were receiving phenytoin, whereas 59% of patients referred to them by non-ED physicians were receiving phenytoin. Seventy-six percent of survey participants responded that they would switch a patient having partial seizures referred from the ED to another AED. Seventy-eight percent indicated that they did not believe that the medications being received by patients with newly diagnosed partial seizures in the ED were suitable for long-term epilepsy treatment.

Conclusion:

Although appropriate treatment might vary in the acute and chronic settings, and phenytoin is used as a primary agent for acute treatment of seizures presenting in the ED, the results of the present survey suggest a discrepancy between the medications that primary care and ED physicians prescribe for newly diagnosed partial seizures and those that specialists prescribe for long-term therapy.     

The availability,condition and employability of automated external defibrillators in large city centres in the Netherlands

Background

In the Netherlands there are, at the time of writing, no clear guidelines about the implementation of automated external defibrillators (AEDs). An observational study was conducted to investigate the current status of AEDs in city centres in the Netherlands looking specifically at the availability, condition and employability of the AEDs.

Methods and results

The shopping areas in the old city centres of the six largest cities in the Netherlands were included in the study. After the AEDs had been identified, a questionnaire was used to determine the availability, condition and employability of the AED. In total 130 AEDs were found and 122 included in the study. The following results were found: 40% of the AEDs were not visible (range 21–64), 29% were not indicated with a sign (range 19–41), 7% had an empty battery (range 0–23), 16% of the defipads had expired (range 0–31) and in 98% of the AEDs a trained employee was present (range 96–100). After combining these results, 71% of the AEDs were available for use (range 61–93), 70% were in a good condition (range 46–82) and 70% were employable (range 58–93). The results show a major variability between cities.

Conclusion

Our study demonstrates that although national guidelines have not been implemented, a reasonable amount of AEDs can be found. However there is certainly room for improvement in the current availability, condition and employability of AEDs in city centres in the Netherlands.     

Effects of implementing a rapid admission policy in the ED

Objective

The purpose of this study is to determine the impact of a new rapid admission policy (RAP) on emergency department (ED) length of stay (EDLOS) and time spent on ambulance diversion (AD).

Methods

The RAP, instituted in January 2005, allows attending emergency physicians to send stable patients, requiring admission to the general medicine service, directly to available inpatient beds. The RAP thereby eliminates 2 conventional preadmission practices: having admitting physicians evaluate the patient in the ED and requiring all diagnostic testing to be complete before admission. We compared patient characteristics, percentage of patients leaving without being seen, EDLOS for admitted patients, time on AD, and total adjusted facility charge for a 3-month period after the RAP implementation to the same period of the prior year.

Results

There was a 1.1% increase in census with no difference in patient demographics, acuity, or disposition categories for the 2 periods. The EDLOS decreased on average by 10.1 minutes (95% confidence interval [CI], 3.3-17.0 minutes), resulting in an average of 4.2 hours of extra bed availability per day. Weekly minutes of AD decreased 169 minutes (95% CI, 29-310 minutes). There was also a 3.2% increase (95% CI, 3.1%-3.3%) in adjusted facility charge between these periods in 2005 compared with 2004.

Conclusions

The RAP resulted in a small decrease in the EDLOS, which likely decreased AD time. The resulting small increase in ED volume and higher acuity ambulance patients significantly improved ED revenue. Wider implementation of the policy and more uniform use among emergency physicians may further improve these measures.     

Prehospital Emergency Care in Shanghai: Present and Future

Background

In Shanghai, prehospital emergency medical services are provided by the public Ambulance Services. The 60th anniversary of the local Ambulance Services is a good opportunity to provide an overview of the current trends in prehospital emergency medical care in Shanghai.

Objectives

In this report, the features of Shanghai prehospital emergency medical care are described, as well as the Shanghai model of purely prehospital emergency medical care, including the communications and dispatch system, ambulance depots and ambulances, and prehospital rescue teams. Responses to major incidents including public health emergencies and natural disasters are also discussed, with the intention of highlighting future directions in emergency medical services, as well as the influence of international trends in emergency patient care.

Discussion

Although Shanghai has the most advanced dispatch system in China (equipped with a Global Positioning System, Global Information System, and more) and can be expanded quickly in case of mass casualty incidents, there is, as yet, no uniform Emergency Medical Service (EMS) dispatching for the entire city. Nor are there certifications, degrees, or special continuing education programs available for EMS dispatchers. Although there are more and more ambulance depots spread all over Shanghai, the city struggles with inadequate prehospital emergency caregivers, because every ambulance has to be staffed with a qualified Emergency Physician, and there are also recruitment problems for ambulance physicians.

Conclusions

Although faced with many challenges, substantial progress is expected in Shanghai prehospital emergency care.