Dispatcher-assisted cardiopulmonary resuscitation. Validation of efficacy

Video-assisted bystander cardiopulmonary resuscitation improves the quality of chest compressions during simulated cardiac arrests: A systemic review and meta-analysis

BACKGROUND

It remains unclear whether video aids can improve the quality of bystander cardiopulmonary resuscitation (CPR).

AIM

To summarize simulation-based studies aiming at improving bystander CPR associated with the quality of chest compression and time-related quality parameters.

METHODS

The systematic review was conducted according to the PRISMA guidelines. All relevant studies were searched through PubMed, EMBASE, Medline and Cochrane Library databases. The risk of bias was evaluated using the Cochrane collaboration tool.

RESULTS

A total of 259 studies were eligible for inclusion, and 6 randomised controlled trial studies were ultimately included. The results of meta-analysis indicated that video-assisted CPR (V-CPR) was significantly associated with the improved mean chest compression rate [OR = 0.66 (0.49-0.82), P < 0.001], and the proportion of chest compression with correct hand positioning [OR = 1.63 (0.71-2.55), P < 0.001]. However, the difference in mean chest compression depth was not statistically significant [OR = 0.18 (-0.07-0.42), P = 0.15], and V-CPR was not associated with the time to first chest compression compared to telecommunicator CPR [OR = -0.12 (-0.88-0.63), P = 0.75].

CONCLUSION

Video real-time guidance by the dispatcher can improve the quality of bystander CPR to a certain extent. However, the quality is still not ideal, and there is a lack of guidance caused by poor video signal or inadequate interaction.

Can high school students teach their peers high quality cardiopulmonary resuscitation (CPR)?

Background

If adolescents can teach each other cardiopulmonary resuscitation (CPR) during school hours, this may be a cost-effective approach to CPR training. The aim of this study was to evaluate CPR quality among students trained by student instructors in CPR.

Material and methods

Three high schools participated. Recruited student instructors (SIs) were given a two-day course by professional instructors. Theoretic knowledge was acquired through an e-learning program. The SIs then trained fellow students in a 90-minute practical CPR session during physical education classes. All participants performed a 4-minutes test of CPR performance. Data was collected using Little Anne QCPR manikins with QCPR classroom software (Laerdal Medical Inc, Norway). Statistical equivalence in CPR performance was assessed applying the two one-sided tests (TOST)-procedure.

Results

Eight professional instructors trained 76 SIs who trained approximately 2650 students in CPR. The number of available tests for analysis of student performance was 982. The compression rates were within guideline recommendations for SIs (mean 110.6, SD 5.4) and students (mean 118.6, SD 8.6). The corresponding numbers for mean compression depth were 7.2 cm (SD 0.7) and 7 cm (SD 1.0). Students demonstrated greater variation in mouth-to-mouth (MTM) skills, with only 41% performing at least 15 successful ventilations during the test. Except for the total number of MTM ventilations (mean difference −5.6), CPR performance was deemed statistically equivalent between professional instructors, SIs and students.

Conclusions

High school students can be trained as CPR instructors and teach fellow students CPR with good quality, with some variation in MTM-ventilation skills.

Phone CPR and barriers affecting life-saving seconds

Objectives: Phone cardiopulmonary resuscitation (CPR) increases the rate of bystander CPR to patients suffering from an out-of-hospital cardiac arrest (OHCA). This study analyzed the effectiveness of the ALERT protocol for instructing laypeople in bystander CPR.Methods: All 244 phone CPR calls to the emergency medical communication center in Leuven during a one-year period were analyzed. Time to recognition of OHCA and to start of phone CPR was evaluated and compared to the recommendations set up by the American Heart Association (AHA). Barriers that delayed or prevented phone CPR were identified.Results: Time to recognition of OHCA and to start of chest compressions was below the benchmark set by the AHA in 37% and 32% of the calls, respectively. The most common barriers that delayed the start of phone CPR were irrelevant questioning by the dispatcher and difficulties moving the patient.In 52 calls, phone CPR was not initiated. In 54% of these calls, this was due to the bystander's inability to move the patient to the floor or to perform CPR. In 44% the bystander's lack of motivation hindered the start of CPR.Conclusions: The ALERT protocol plays a key role in bystander-CPR. Despite the increased CPR rates and reduced time to start chest compressions since its implementation, further improvement is required. Based on the barriers detected, intensive training of dispatchers is an important next step. Furthermore, adding an alternative track to the protocol for immovable patients might be worth considering.

Dispatcher instructions for bystander cardiopulmonary resuscitation and neurologically intact survival after bystander-witnessed out-of-hospital cardiac arrests: a nationwide, population-based observational study

Background

The International Liaison Committee on Resuscitation recommends that dispatchers provide instructions to perform compression-only cardiopulmonary resuscitation (CPR) to callers responding to adults with out-of-hospital cardiac arrest (OHCA). This study aimed to determine the optimal dispatcher-assisted CPR (DA-CPR) instructions for OHCA.

Methods

We analysed the records of 24,947 adult patients (aged ≥ 18 years) who received bystander DA-CPR after bystander-witnessed OHCA. Data were obtained from a prospectively recorded Japanese nationwide Utstein-style database for a 2-year period (2016–2017). Patients were divided into compression-only DA-CPR (n = 22,778) and conventional DA-CPR (with a compression-to-ventilation ratio of 30:2, n = 2169) groups. The primary outcome measure was 1-month neurological intact survival, defined as a cerebral performance category score of 1–2 (CPC 1–2).

Results

The 1-month CPC 1–2 rate was significantly higher in the conventional DA-CPR group than in the compression-only DA-CPR group (before propensity score (PS) matching, 7.5% [162/2169] versus 5.8% [1309/22778], p < 0.01; after PS matching, 7.5% (162/2169) versus 5.7% (123/2169), p < 0.05). Compared with compression-only DA-CPR, conventional DA-CPR was associated with increased odds of 1-month CPC 1–2 (before PS matching, adjusted odds ratio 1.39, 95% confidence interval [CI] 1.14–1.70, p < 0.01; after PS matching, adjusted odds ratio 1.34, 95% CI 1.00–1.79, p < 0.05).

Conclusion

Within the limitations of this retrospective observational study, conventional DA-CPR with a compression-to-ventilation ratio of 30:2 was preferable to compression-only DA-CPR as an optimal DA-CPR instruction for coaching callers to perform bystander CPR for adult patients with bystander-witnessed OHCAs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03825-w.

Effectiveness of a Dispatcher-Assisted Cardiopulmonary Resuscitation Program Developed by the Thailand National Institute of Emergency Medicine (NIEMS)

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) is a life-threatening condition with an overall survival rate that generally does not exceed 10%. Several factors play essential roles in increasing survival among patients experiencing cardiac arrest outside the hospital. Previous studies have reported that implementing a dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) program increases bystander CPR, quality of chest compressions, and patient survival. This study aimed to assess the effectiveness of a DA-CPR program developed by the Thailand National Institute for Emergency Medicine (NIEMS).

METHODS

This was an experimental study using a manikin model. The participants comprised both health care providers and non-health care providers aged 18 to 60 years. They were randomly assigned to either the DA-CPR group or the uninstructed CPR (U-CPR) group and performed chest compressions on a manikin model for two minutes. The sequentially numbered, opaque, sealed envelope method was used for randomization in blocks of four with a ratio of 1:1.

RESULTS

There were 100 participants in this study (49 in the DA-CPR group and 51 in the U-CPR group). Time to initiate chest compressions was statistically significantly longer in the DA-CPR group than in the U-CPR group (85.82 [SD = 32.54] seconds versus 23.94 [SD = 16.70] seconds; P <.001). However, the CPR instruction did not translate into better performance or quality of chest compressions for the overall sample or for health care or non-health care providers.

CONCLUSION

Those in the CPR-trained group applied chest compressions (initiated CPR) more quickly than those who initiated CPR based upon dispatch-based CPR instructions.

Dispatcher-assisted conventional cardiopulmonary resuscitation and outcomes for paediatric out-of-hospital cardiac arrests

AIM

As asphyxial cardiac arrest is more common than cardiac arrest from a primary cardiac event in paediatric cardiac arrest, effective ventilation is important during paediatric cardiopulmonary resuscitation (CPR). We aimed to determine optimal dispatcher-assisted CPR instructions for bystanders after paediatric out-of-hospital cardiac arrest (OHCA).

METHODS

We analysed the records of 8172 children who received bystander dispatcher-assisted CPR. Data were obtained from an All-Japan Utstein-style registry from 2005 to 2017. Patients were divided into conventional CPR and compression-only CPR groups. The primary study endpoint was 1-month neurologically intact survival, defined as a Cerebral Performance Category score of 1 or 2 (CPC 1-2).

RESULTS

The 1-month CPC 1-2 rate was significantly higher in the dispatcher-assisted conventional CPR group than in the dispatcher-assisted compression-only CPR group (before propensity score matching, 5.7% [175/3077] vs. 3.1% [160/5095], p < 0.0001, adjusted odds ratio 2.48, 95% confidence interval 1.19-3.22; after propensity score matching, 6.0% [156/2618] vs. 2.6% [69/2618], p < 0.0001, adjusted odds ratio 2.42, 95% confidence interval 1.76-3.32). In most subgroup analyses after matching, dispatcher-assisted conventional CPR had a higher CPC 1-2 rate than dispatcher-assisted compression-only CPR; however, CPC 1-2 rates were similar between the two groups for patients with an initial shockable rhythm, those with total prehospital CPR time ≥ 20 min, those receiving public access defibrillation, advanced airway management, or adrenaline administration.

CONCLUSION

Within the limitations of this retrospective observational study, dispatcher-assisted conventional CPR was preferable to dispatcher-assisted compression-only CPR as optimal CPR instructions for coaching callers to perform bystander CPR.

Impact of Dispatcher-Assisted Bystander Cardiopulmonary Resuscitation with Out-of-Hospital Cardiac Arrest: A Systemic Review and Meta-Analysis

OBJECTIVE

This systemic review and meta-analysis was conducted to explore the impact of dispatcher-assisted bystander cardiopulmonary resuscitation (DA-BCPR) on bystander cardiopulmonary resuscitation (BCPR) probability, survival, and neurological outcomes with out-of-hospital cardiac arrest (OHCA).

METHODS

Electronically searching of PubMed, Embase, and Cochrane Library, along with manual retrieval, were done for clinical trials about the impact of DA-BCPR which were published from the date of inception to December 2018. The literature was screened according to inclusion and exclusion criteria, the baseline information, and interested outcomes were extracted. Two reviewers assessed the methodological quality of the included studies. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated by STATA version 13.1.

RESULTS

In 13 studies, 235,550 patients were enrolled. Compared with no dispatcher instruction, DA-BCPR tended to be effective in improving BCPR rate (I2 = 98.2%; OR = 5.84; 95% CI, 4.58-7.46; P <.01), return of spontaneous circulation (ROSC) before admission (I2 = 36.0%; OR = 1.17; 95% CI, 1.06-1.29; P <.01), discharge or 30-day survival rate (I2 = 47.7%; OR = 1.25; 95% CI, 1.06-1.46; P <.01), and good neurological outcome (I2 = 30.9%; OR = 1.24; 95% CI, 1.04-1.48; P = .01). However, no significant difference in hospital admission was found (I2 = 29.0%; OR = 1.09; 95% CI, 0.91-1.30; P = .36).

CONCLUSION

This review shows DA-BPCR plays a positive role for OHCA as a critical section in the life chain. It is effective in improving the probability of BCPR, survival, ROSC before admission, and neurological outcome.

Interventions to improve the quality of bystander cardiopulmonary resuscitation: A systematic review

Background

Performing high-quality bystander cardiopulmonary resuscitation (CPR) improves the clinical outcomes of victims with sudden cardiac arrest. Thus far, no systematic review has been performed to identify interventions associated with improved bystander CPR quality.

Methods

We searched Ovid MEDLINE, Ovid EMBASE, EBSCO CINAHL, Ovid PsycInfo, Thomson Reuters SCI-EXPANDED, and the Cochrane Central Register of Controlled Trials to retrieve studies published from 1 January 1966 to 5 October 2018 associated with interventions that could improve the quality of bystander CPR. Data regarding participant characteristics, interventions, and design and outcomes of included studies were extracted.

Results

Of the initially identified 2,703 studies, 42 were included. Of these, 32 were randomized controlled trials. Participants included adults, high school students, and university students with non-medical professional majors. Interventions improving bystander CPR quality included telephone dispatcher-assisted CPR (DA-CPR) with simplified or more concrete instructions, compression-only CPR, and other on-scene interventions, such as four-hand CPR for elderly rescuers, kneel on opposite sides for two-person CPR, and CPR with heels for a tired rescuer. Devices providing real-time feedback and mobile devices containing CPR applications or software were also found to be beneficial in improving the quality of bystander CPR. However, using mobile devices for improving CPR quality or for assisting DA-CPR might cause rescuers to delay starting CPR.

Conclusions

To further improve the clinical outcomes of victims with cardiac arrest, these effective interventions may be included in the guidelines for bystander CPR.

Comparison of Cardiopulmonary Resuscitation Quality Between Standard Versus Telephone-Basic Life Support Training Program in Middle-Aged and Elderly Housewives: A Randomized Simulation Study

INTRODUCTION

For cardiac arrests witnessed at home, the witness is usually a middle-aged or older housewife. We compared the quality of cardiopulmonary resuscitation (CPR) performance of bystanders trained with the newly developed telephone-basic life support (T-BLS) program and those trained with standard BLS (S-BLS) training programs.

METHODS

Twenty-four middle-aged and older housewives without previous CPR education were enrolled and randomized into two groups of BLS training programs. The T-BLS training program included concepts and current instruction protocols for telephone-assisted CPR, whereas the S-BLS training program provided training for BLS. After each training course, the participants simulated CPR and were assisted by a dispatcher via telephone. Cardiopulmonary resuscitation quality was measured and recorded using a mannequin simulator. The primary outcome was total no-flow time (>1.5 seconds without chest compression) during simulation.

RESULTS

Among 24 participants, two (8.3%) who experienced mechanical failure of simulation mannequin and one (4.2%) who violated simulation protocols were excluded at initial simulation, and two (8.3%) refused follow-up after 6 months. The median (interquartile range) total no-flow time during initial simulation was 79.6 (66.4-96.9) seconds for the T-BLS training group and 147.6 (122.5-184.0) seconds for the S-BLS training group (P < 0.01). Median cumulative interruption time and median number of interruption events during BLS at initial simulation and 6-month follow-up simulation were significantly shorter in the T-BLS than in the S-BLS group (1.0 vs. 9.5, P < 0.01, and 1.0 vs. 10.5, P = 0.02, respectively).

CONCLUSIONS

Participants trained with the T-BLS training program showed shorter no-flow time and fewer interruptions during bystander CPR simulation assisted by a dispatcher.

The role of dispatch in resuscitation

The role of the dispatch centre has increasingly become a focus of attention in cardiac arrest resuscitation. The dispatch centre is part of the first link in the chain of survival because without the initiation of early access, the rest of the chain is irrelevant. The influence of dispatch can also extend to the initiation of bystander cardiopulmonary resuscitation, early defibrillation and the rapid dispatch of emergency ambulances. The new International Liaison Committee on Resuscitation, the American Heart Association and, especially, the European Resuscitation Council 2015 guidelines have been increasing their emphasis on dispatch as the key to improving out-of-hospital cardiac arrest survival.

Strengthening Links in the “Chain of Survival”: A Singapore Perspective

Introduction

The concept of the chain of survival is widely accepted. The four links viz. early access, early cardiopulmonary resuscitation (CPR), early defibrillation and early Advanced Cardiac Life Support (ACLS) are related to survival after pre-hospital cardiac arrest. Owing to the dismal survival-to-discharge figures locally, we conducted this study to identify any weaknesses in the chain, looking in particular at bystander CPR rates and times to Basic Cardiac Life Support (BCLS) and ACLS.

Methods and materials

A retrospective cohort study was conducted in the Emergency Department of an urban tertiary 1500-bed hospital. Over a 12-month period, all cases of non-trauma out-of-hospital cardiac arrest were evaluated.

Results

A total of 142 cases of non-trauma out-of-hospital cardiac arrest were identified; the majority being Chinese (103/142, 72.5%) and male (71.8%) with a mean age of 64.3±7.8 years (range 23–89 yrs). Most patients (111/142, 78.2%) did not receive any form of life support until arrival of the ambulance crew. Mean time from collapse to arrival of the ambulance crew and initiation of BCLS and defibrillation was 9.2±3.5 minutes. Mean time from collapse to arrival in the Emergency Department (and thus ACLS) was 16.8±7.1 minutes. Three patients (2.11%) survived to discharge.

Conclusion

There is a need to (i) facilitate layperson training in bystander CPR, and (ii) enhance paramedic training to include ACLS, in order to improve the current dismal survival outcomes from out-of-hospital cardiac arrest in Singapore.

Safety and applicability of a pre-stage public access ventilator for trained laypersons: a proof of principle study

BACKGROUND

Contemporary resuscitation guidelines for basic life support recommend an immediate onset of cardiac compressions in case of cardiac arrest followed by rescue breaths. Effective ventilation is often omitted due to fear of doing harm and fear of infectious diseases. In order to improve ventilation a pre-stage of an automatic respirator was developed for use by laypersons.

METHODS

Fifty-two healthy volunteers were ventilated by means of a prototype respirator via a full-face mask in a pilot study. The pre-stage public access ventilator (PAV) consisted of a low-cost self-designed turbine, with sensors for differential pressure, flow, FO₂, FCO₂ and 3-axis acceleration measurement. Sensor outputs were used to control the respirator and to recognize conditions relevant for efficiency of ventilation and patients' safety. Different respiratory manoeuvres were applied: a) pressure controlled ventilation (PCV), b) PCV with controlled leakage and c) PCV with simulated airway occlusion. Sensor signals were analysed to detect leakage and airway occlusion. Detection based upon sensor signals was compared with evaluation based on clinical observation and additional parameters such as exhaled CO₂.

RESULTS

Pressure controlled ventilation could be realized in all volunteers. Leakage was recognized with 93.5% sensitivity and 93.5% specificity. Simulated airway occlusion was detected with 91.8% sensitivity and 91.7% specificity.

CONCLUSION

The pre-stage PAV was able to detect potential complications relevant for patients' safety such as leakage and airway occlusion in a proof of principle study. Prospectively, this device provides a respectable basis for the development of an automatic emergency respirator and may help to improve bystander resuscitation.

Association between public cardiopulmonary resuscitation education and the willingness to perform bystander cardiopulmonary resuscitation: a metropolitan citywide survey

OBJECTIVE

Bystander cardiopulmonary resuscitation (CPR) is an important factor associated with improved survival rates and neurologic prognoses in cases of out-of-hospital cardiac arrest. We assessed how factors related to CPR education including timing of education, period from the most recent education session, and content, affected CPR willingness.

METHODS

In February 2012, trained interviewers conducted an interview survey of 1,000 Daegu citizens through an organized questionnaire. The subjects were aged ≥19 years and were selected by quota sampling. Their social and demographic characteristics, as well as CPR and factors related to CPR education, were investigated. Chi-square tests and multivariate logistic regression analyses were used to evaluate how education-related factors affected the willingness to perform CPR.

RESULTS

Of total 1,000 cases, 48.0% were male. The multivariate analyses revealed several factors significantly associated with CPR willingness: didactic plus practice group (adjusted odds ratio [AOR], 3.38; 95% confidence interval [CI], 2.3 to 5.0), group with more than four CPR education session (AOR, 7.68; 95% CI, 3.21 to 18.35), interval of less than 6 months from the last CPR education (AOR, 4.47; 95% CI 1.29 to 15.52), and education with automated external defibrillator (AOR, 5.98; 95% CI 2.30 to 15.53).

CONCLUSION

The following were associated with increased willingness to perform CPR: practice sessions and automated electrical defibrillator training in public CPR education, more frequent CPR training, and shorter time period from the most recent CPR education sessions.

Augmented survival of out-of-hospital cardiac arrest victims with the use of mobile phones for emergency communication under the DA-CPR protocol getting information from callers beside the victim

PURPOSE

To investigate the impacts of emergency calls made using mobile phones on the quality of dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) and survival from out-of-hospital cardiac arrests (OHCAs) that were not witnessed by emergency medical service (EMS).

METHODS

In this prospective study, we collected data for 2530 DA-CPR-attempted medical emergency cases (517 using mobile phones and 2013 using landline phones) and 2980 non-EMS-witnessed OHCAs (600 using mobile phones and 2380 using landline phones). Time factors and quality of DA-CPR, backgrounds of callers and outcomes of OHCAs were compared between mobile and landline phone groups.

RESULTS

Emergency calls are much more frequently placed beside the arrest victim in mobile phone group (52.7% vs. 17.2%). The positive predictive value and acceptance rate of DA-CPR in mobile phone group (84.7% and 80.6%, respectively) were significantly higher than those in landline group (79.2% and 70.9%). The proportion of good-quality bystander CPR in mobile phone group was significantly higher than that in landline group (53.5% vs. 45.0%). When analysed for all non-EMS-witnessed OHCAs, rates of 1-month survival and 1-year neurologically favourable survival in mobile phone group (7.8% and 3.5%, respectively) were higher than those in landline phone group (4.6% and 1.9%; p<0.05). Multiple logistic regression analysis, including other backgrounds, revealed that mobile phone calls were associated with increased 1-month survival in the subgroup of OHCAs receiving bystander CPR (adjusted odds ratio, 1.84; 95% CI, 1.15-2.92).

CONCLUSION

Emergency calls made using mobile phones are likely to augment the survival from OHCAs by improving DA-CPR.

Impact of an emergency medical dispatch system on survival from out-of-hospital cardiac arrest: a population-based study

Background

In countries where a single public emergency telephone number is not in operation, different emergency telephone numbers corresponding to multiple dispatch centres (police, fire, emergency medical service) may create confusion for the population about the most appropriate service to call. In particular, out-of-hospital cardiac arrest (OHCA) requires a prompt and effective response. We compare two different dispatch systems on OHCA patient survival at 30 days in a national system with multiple emergency telephone numbers.

Methods

We conducted an observational retrospective study of 6871 patients aged 18 years or older with presumed OHCA of cardiac origin between 2005 and 2013 in three counties of the Northern French Alps region. One county had a single dispatch centre combining medical and fire emergencies, and two had multiple dispatch centres. Propensity score matching analyses were performed to compare patient survival at 30 days.

Results

A total of 2257 emergency calls for OHCA were managed by a single dispatch centre and 4614 by a multiple dispatch centre. A single dispatch centre was associated with an increase in survival (adjusted odds ratio [OR] for all patients: 1.7; 95 % confidence interval [CI] = 1.3–2.2; p <0.001; adjusted OR for propensity-matched patients: 2.0; 95 % CI = 1.2–3.4; p = 0.012).

Conclusions

A single dispatch centre was associated with a markedly improved increase of survival among OHCA patients at 30 days in a system with several emergency telephone numbers.

Electronic supplementary material

The online version of this article (doi:10.1186/s13049-016-0247-y) contains supplementary material, which is available to authorized users.

Understanding and improving low bystander CPR rates: a systematic review of the literature

Objectives:

Cardiopulmonary resuscitation (CPR) is a crucial yet weak link in the chain of survival for out-of-hospital cardiac arrest. We sought to understand the determinants of bystander CPR and the factors associated with successful training.

Methods:

For this systematic review, we searched 11 electronic databases, 1 trial registry and 9 scientific websites. We performed hand searches and contacted 6 content experts. We reviewed without restriction all communications pertaining to who should learn CPR, what should be taught, when to repeat training, where to give CPR instructions and why people lack the motivation to learn and perform CPR. We used standardized forms to review papers for inclusion, quality and data extraction. We grouped publications by category and classified recommendations using a standardized classification system that was based on level of evidence.

Results:

We reviewed 2409 articles and selected 411 for complete evaluation. We included 252 of the 411 papers in this systematic review. Differences in their study design precluded a meta-analysis. We classified 22 recommendations; those with the highest scores were 1) 9-1-1 dispatch-assisted CPR instructions, 2) teaching CPR to family members of cardiac patients, 3) Braslow's self-training video, 4) maximizing time spent using manikins and 5) teaching the concepts of ambiguity and diffusion of responsibility. Recommendations not supported by evidence include mass training events, pulse taking prior to CPR by laymen and CPR using chest compressions alone.

Conclusion:

We evaluated and classified the potential impact of interventions that have been proposed to improve bystander CPR rates. Our results may help communities design interventions to improve their bystander CPR rates.

Survey of a Protocol to Increase Appropriate Implementation of Dispatcher-Assisted Cardiopulmonary Resuscitation for Out-of-Hospital Cardiac Arrest

Background—

Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) attempts to improve the management of out-of-hospital cardiac arrest by laypersons who are unable to recognize cardiac arrest and are unfamiliar with CPR. Therefore, we investigated the sensitivity and specificity of our new DA-CPR protocol for achieving implementation of bystander CPR in out-of-hospital cardiac arrest victims not already receiving bystander CPR.

Methods and Results—

Since 2007, we have applied a new DA-CPR protocol that uses supplementary key words. Fire departments prospectively collected baseline data on DA-CPR from January 2009 to December 2011. DA-CPR was attempted in 2747 patients; of these, 417 (15.2%) did not experience cardiac arrest. The sensitivity and specificity of the 2007 protocol versus estimated values of the previous standard protocol were 72.9% versus 50.3% and 99.6% versus 99.8%, respectively. We identified key words that may be useful for detecting out-of-hospital cardiac arrest. Multiple logistic regression analysis revealed that the occurrence of cardiac arrest after an emergency call (odds ratio, 16.85) and placing an emergency call away from the scene of the arrest (odds ratio, 11.04) were potentially associated with failure to provide DA-CPR. Furthermore, at-home cardiac arrest (odds ratio, 1.61) and family members as bystanders (odds ratio, 1.55) were associated with bystander noncompliance with DA-CPR. No complications were reported in the 417 patients who received DA-CPR but did not have cardiac arrest.

Conclusions—

Our 2007 protocol is safe and highly specific and may be more sensitive than the standard protocol. Understanding the factors associated with failure of bystanders to provide DA-CPR and implementing public education are necessary to increase the benefit of DA-CPR.

Quality of CPR performed by trained bystanders with optimized pre-arrival instructions

OBJECTIVE

Telephone-CPR (T-CPR) can increase initiation of bystander CPR. We wanted to study if quality oriented continuous T-CPR would improve CPR performance vs. standard T-CPR.

METHOD

Ninety-five trained rescuers aged 22-69 were randomized to standard T-CPR or experimental continuous T-CPR (comprises continuous instructions, questions and encouragement). They were instructed to perform 10 min of chest compressions-only on a manikin, which recorded CPR performance in a small, confined kitchen. Three video-cameras captured algorithm time data, CPR technique and communication. Demography and training experience were captured during debriefing.

RESULTS

Participants receiving continuous T-CPR delivered significantly more chest compressions (median 1000 vs. 870 compressions, p=0.014) and compressed more frequently to a compression rate between 90 and 120 min(-1) (median 87% vs. 60% of compressions, p<0.001), compared to those receiving standard T-CPR. This also resulted in less time without compressions after CPR had started (median 12s vs. 64 s, p<0.001), but longer time interval from initiating contact with dispatcher to first chest compression (median 144 s vs. 84 s, p<0.001). There was no difference in chest compression depth (mean 47 mm vs. 48 mm, p = 0.90) or in demography, education and previous CPR training between the groups.

CONCLUSION

In our simulated scenario with CPR trained lay rescuers, experimental continuous T-CPR gave better chest compression rate and less hands-off time during CPR, but resulted in delayed time to first chest compression compared to standard T-CPR instructions.

New pre-arrival instructions can avoid abdominal hand placement for chest compressions

OBJECTIVE

To investigate if modified pre-arrival instructions using patient's arm and nipple line as landmarks could avoid abdominal hand placements for chest compressions.

METHOD

Volunteers were randomized to one of two telephone instructions: "Kneel down beside the chest. Place one hand in the centre of the victim's chest and the other on top" (control) or "Lay the patient's arm which is closest to you, straight out from the body. Kneel down by the patient and place one knee on each side of the arm. Find the midpoint between the nipples and place your hands on top of each other" (intervention). Hand placement was conducted on an adult male and documented by laser measurements. Hand placement, quantified as the centre of the compressing hands in the mid-sagittal plane, was compared to the inter-nipple line (INL) for reference and classified as above or below. Fisher's exact test was used for comparison of proportions.

RESULTS

Thirty-six lay people, age range 16-60, were included. None in the intervention group placed their hands in the abdominal region, compared to 5/18 in the control group (p = 0.045). Using INL as a reference, the new instructions resulted in less caudal hand placement, and the difference in mean hand position was 47 mm [95% CI 21,73], p = 0.001.

CONCLUSION

New pre-arrival instructions where the patient's arm and nipple line were used as landmarks resulted in less caudal hand placements and none in the abdominal region.

Efficacy of metronome sound guidance via a phone speaker during dispatcher-assisted compression-only cardiopulmonary resuscitation by an untrained layperson: a randomised controlled simulation study using a manikin

AIM

Untrained laypersons should perform compression-only cardiopulmonary resuscitation (COCPR) under a dispatcher's guidance, but the quality of the chest compressions may be suboptimal. We hypothesised that providing metronome sounds via a phone speaker may improve the quality of chest compressions during dispatcher-assisted COCPR (DA-COCPR).

METHODS

Untrained laypersons were allocated to either the metronome sound-guided group (MG), who performed DA-COCPR with metronome sounds (110 ticks/min), or the control group (CG), who performed conventional DA-COCPR. The participants of each group performed DA-COCPR for 4 min using a manikin with Skill-Reporter, and the data regarding chest compression quality were collected.

RESULTS

The data from 33 cases of DA-COCPR in the MG and 34 cases in the CG were compared. The MG showed a faster compression rate than the CG (111.9 vs 96.7/min; p=0.018). A significantly higher proportion of subjects in the MG performed the DA-COCPR with an accurate chest compression rate (100-120/min) compared with the subjects in the CG (32/33 (97.0%) vs 5/34 (14.7%); p<0.0001). The mean compression depth was not different between the MG and the CG (45.9 vs 46.8 mm; p=0.692). However, a higher proportion of subjects in the MG performed shallow compressions (compression depth <38 mm) compared with subjects in the CG (median % was 69.2 vs 15.7; p=0.035).

CONCLUSIONS

Metronome sound guidance during DA-COCPR for the untrained bystanders improved the chest compression rates, but was associated more with shallow compressions than the conventional DA-COCPR in a manikin model.

Triage By Emergency Medical Dispatchers

Purpose:

This study is an evaluation of the ability of medically trained and controlled emergency medical dispatchers to use telephone triage techniques to direct the appropriate prehospital unit to an emergency scene.

Methods:

Emergency dispatchers, educated in a formal emergency medical dispatch program, were assigned one of four triage priorities to incoming 9-1-1 calls. The actual field management delivered for each patient was compared with the dispatcher's triage to determine the appropriateness of triage.

Results:

A total of 1,045 consecutive calls were reviewed with 74.4% sorted as needing advanced life support (ALS) units on scene; 65.3% (95% CI, 61.9 to 68.6%) of these calls required ALS intervention. A total of 3.4% of the runs sorted to the non-ALS response groups were identified to have required ALS intervention. Comparing the need for ALS intervention, a significant difference was found between the triage groups.

Conclusion:

Emergency medical dispatchers, using a formal system for telephone triage, are able to direct appropriate prehospital resources to the emergency scene.

Time to first compression using Medical Priority Dispatch System compression-first dispatcher-assisted cardiopulmonary resuscitation protocols

INTRODUCTION

Without bystander cardiopulmonary resuscitation (CPR), cardiac arrest survival decreases 7%-10% for every minute of delay until defibrillation. Dispatcher-assisted CPR (D-CPR) has been shown to increase the rates of bystander CPR and cardiac arrest survival. Other reports suggest that the most critical component of bystander CPR is chest compressions with minimal interruption. Beginning with version 11.2 of the Medical Priority Dispatch System (MPDS) protocols, instructions for mouth-to-mouth ventilation (MTMV) and pulse check were removed and a compression-first pathway was introduced to facilitate rapid delivery of compressions. Additionally, unconscious choking and third-trimester pregnancy decision-making criteria were added in versions 11.3 and 12.0, respectively. However, the effects of these changes on time to first compression (TTFC) have not been evaluated.

OBJECTIVE

We sought to quantify the TTFC of MPDS versions 11.2, 11.3, and 12.0 for all calls identified as cardiac arrest on call intake that did not require MTMV instruction.

METHODS

Audio recordings of all D-CPR events for October 2005 through May 2010 were analyzed for TTFC. Differences in TTFC across versions were compared using the Kruskal-Wallis test.

RESULTS

A total of 778 cases received D-CPR. Of these, 259 were excluded because they met criteria for MTMV (pediatric patients, allergic reaction, etc.), were missing data, or were not initially identified as cardiac arrest. Of the remaining 519 calls, the mean TTFC was 240 seconds, with no significant variation across the MPDS versions (p = 0.08).

CONCLUSIONS

Following the removal of instructions for pulse check and MTMV, as well as other minor changes in the MPDS protocols, we found the overall TTFC to be 240 seconds with little variation across the three versions evaluated. This represents an improvement in TTFC compared with reports of an earlier version of MPDS that included pulse checks and MTMV instructions (315 seconds). However, the MPDS TTFC does not compare favorably with reports of older, non-MPDS protocols that included pulse checks and MTMV. Efforts should continue to focus on improving this key, and modifiable, determinant of cardiac arrest survival.

Video analysis of dispatcher-rescuer teamwork-Effects on CPR technique and performance

OBJECTIVE

We wanted to study the effect of continuous dispatcher communication on CPR technique and performance during 10min of simulated cardiac arrest.

METHOD

We reviewed video recordings and manikin data from 30 CPR trained lay people who where left alone in a simulated cardiac arrest situation with a manikin in a home-like environment (in a small, confined kitchen with the disturbing noise of a radio). CPR was performed for 10min with continuous telephone instructions via speaker function from a dispatcher. The dispatcher was blinded for CPR performance and video. Dispatcher communication, compression technique and ventilation technique was scored as accomplished or failed in the 1st and 10th minute.

RESULTS

29/30 rescuers were able to hear instructions, answer questions from the dispatcher and perform CPR in parallel. Rescuer position beside manikin was initially correct for 13/30, improving to 21/30 (p=0.008). Compression technique was adequate for the whole episode, with an insignificant trend for improvement; 29 to 30/30 using straight arms, 28 to 30/30 in a vertical position over chest and 24 to 27/30 counting loudly. 17/29 placed their hands between the nipples initially, improving to 24/29 (p=0.065). Mean compression rate improved from 84 to 101min(-1) (p<0.001), and compression depth maintained adequate (43 to 42mm). Initially, 17/29 used chin-lift manoeuvre, 14/30 used head-tilt and 19/29 used nose pinch to manage open airways, compared to 18, 20 and 22/29 (ns) in the 10th minute, respectively. Successful delivery of ventilation improved from 13/30 to 23/30 (p=0.006).

CONCLUSION

Bystander and dispatcher can communicate successfully during ongoing CPR using a telephone with speaker function. CPR technique and quality improved or did not change over 10min with continuous dispatcher assistance. These results suggest a potential for improved bystander CPR using rescuer-dispatcher teamwork.

Are trained individuals more likely to perform bystander CPR? An observational study

BACKGROUND

This study aimed to evaluate the association of cardiopulmonary resuscitation (CPR) training with bystander resuscitation performance and patient outcomes after out-of-hospital cardiac arrest (OHCA).

METHODS

This was a prospective, population-based cohort study of all persons aged 18 years or older with OHCA of presumed intrinsic origin and their rescuers from January through December 2008 in Takatsuki, Osaka prefecture, Japan. Data on resuscitation of OHCA patients were obtained by emergency medical service (EMS) personnel in charge based on the Utstein style. Rescuers' characteristics including experience of CPR training were obtained by EMS personnel interview on the scene. The primary outcome was the attempt of bystander CPR.

RESULTS

Data were collected for 120 cases out of 170 OHCAs of intrinsic origin. Among the available cases, 60 (50.0%) had previous CPR training (trained rescuer group). The proportion of bystander CPR was significantly higher in the trained rescuer group than in the untrained rescuer group (75.0% and 43.3%; p = 0.001). Bystanders who had previous experience of CPR training were 3.40 times (95% confidence interval 1.31-8.85) more likely to perform CPR compared with those without previous CPR training. The number of patients with neurologically favorable one-month survival was too small to evaluate statistical difference between the groups (2 [3.3%] in the trained rescuer group versus 1 [1.7%] in the untrained rescuer group; p = 0.500).

CONCLUSIONS

People who had experienced CPR training had a greater tendency to perform bystander CPR than people without experience of CPR training. Further studies are needed to prove the effectiveness of CPR training on survival.

Dispatcher-assisted telephone cardiopulmonary resuscitation using a French-language compression-only protocol in volunteers with or without prior life support training: A randomized trial

OBJECTIVES

Due to the recent interest in hands-only protocols for dispatcher-assisted cardiopulmonary resuscitation (CPR) and the lack of any validated algorithms in French, our primary objective was to evaluate a new French-language protocol in terms of its efficacy to help previously untrained volunteers in performing basic life support efforts of appropriate quality, and secondarily to investigate its potential utility in subjects with previous training.

METHODS

Untrained volunteers were recruited among adults in a public movie centre and previously trained volunteers among undergraduate nursing students. Participants were randomly assigned to 'phone CPR' versus 'no phone CPR' by drawing sets of envelopes. Primary outcome measures were the results of the Cardiff evaluation test; the secondary measures were global scoring of a complete 5min period of CPR, in a manikin model of cardiac arrest.

RESULTS

Out of 146 volunteers assessed for eligibility, 36 previously untrained candidates declined participation. 110 participants, distributed into four groups, completed the study: the previously untrained non-guided group (group A, n=30), the previously untrained guided group (group B, n=30), the previously trained non-guided group (group C, n=25) and the previously trained guided group (group D, n=25). Results of the Cardiff test and global evaluation of CPR performance revealed a significant improvement in group B as compared with group A, approaching the level of the group C. Previously trained guided bystanders had the best CPR scores, notably because of an improvement in the quality of airway management.

CONCLUSION

When used by dispatchers, this new French-language algorithm offers the opportunity to help previously untrained bystanders initiate CPR. The same protocol may serve to guide volunteers with prior basic life support training to reach their best CPR performance.

A Simulation Trial of Traditional Dispatcher-Assisted CPR Versus Compressions—Only Dispatcher-Assisted CPR

OBJECTIVES

Growing evidence indicates that it may not be essential to deliver ventilations in the first few minutes of CPR. We compared time to delivery of first compression in traditional CPR with ventilations and compressions to compression-only CPR performed by untrained laypersons assisted by a mock 911 dispatcher.

METHODS

This randomized-controlled simulation study included a convenience sample of English-speaking emergency department visitors during a 6-month period. Exclusion criteria were prior CPR training or physical incapacity. A cardiac arrest scenario was presented to subjects who were then provided with one of two sets of telephone CPR instructions by a mock 911 dispatcher. One group received traditional CPR instructions (TCPR) and the second group received compression only CPR instructions (COCPR). Subjects performed CPR on a Laerdal Resusci-Anne CPR manikin and recording strips were analyzed for frequency and quality measures. Pre-and post-test questionnaires assessed subject fatigue and telephone instruction understanding. The primary outcome was the time interval from 911 call to initiation of chest compressions. Analysis included Student t-test, Chi-square, and Wilcoxon Rank Sum.

RESULTS

Of 377 potential subjects, 54 consented to randomization. The data from 50 subjects were analyzed. Compared to group TCPR, group COCPR initiated chest compressions faster (72 vs 117 sec, p < 0.0001), completed four cycles of CPR faster (168 vs. 250 sec, p < 0.0001), and paused for a smaller percentage of the resuscitation (13% vs. 36%, p < 0.0001). Only 9% of ventilation opportunities in the TCPR group yielded ventilations of the correct volume. There were no differences between groups in perceived understanding of CPR instruction or fatigue.

CONCLUSIONS

We have identified the potential timesavings that may occur during compressions-only CPR. Bystander resuscitation may be more efficient when ventilations are excluded from the CPR sequence.

Interactive video instruction improves the quality of dispatcher-assisted chest compression-only cardiopulmonary resuscitation in simulated cardiac arrests

OBJECTIVE

Bystander cardiopulmonary resuscitation (CPR) significantly improves survival of cardiac arrest victims. Dispatch assistance increases bystander CPR, but the quality of dispatcher-assisted CPR remains unsatisfactory. This study was conducted to assess the effect of adding interactive video communication to dispatch instruction on the quality of bystander chest compressions in simulated cardiac arrests.

DESIGN

A randomized controlled study with a scenario developed to simulate cardiac arrest in a public place.

SETTING

The victim was simulated by a mannequin and the cell phone for dispatch assistance was a video cell phone with both voice and video modes. Chest compression-only CPR instruction was used in the dispatch protocol.

SUBJECTS

Ninety-six adults without CPR training within 5 years were recruited.

INTERVENTIONS

The subjects were randomized to receive dispatch assistance on chest compression with either voice instruction alone (voice group, n = 53) or interactive voice and video demonstration and feedback (video group, n = 43) via a video cell phone.

MEASUREMENTS AND MAIN RESULTS

Performance of chest compression-only CPR throughout the scenario was videotaped. The quality of CPR was evaluated by reviewing the videos and mannequin reports. Chest compressions among the video group were faster (median rate 95.5 vs. 63.0 min-1, p < 0.01), deeper (median depth 36.0 vs. 25.0 mm, p < 0.01), and of more appropriate depth (20.0% vs. 0%, p < 0.01). The video group had more "hands-off" time (5.0 vs. 0 second, p < 0.01), longer time to first chest compression (145.0 vs. 116.0 seconds, p < 0.01) and total instruction time (150.0 vs. 121.0 seconds, p < 0.01).

CONCLUSION

The addition of interactive video communication to dispatcher-assisted chest compression-only CPR initially delayed the commencement of chest compressions, but subsequently improved the depth and rate of compressions. The benefit was achieved mainly through real-time feedback.

Handling of drug-related emergencies: an evaluation of emergency medical dispatch

AIMS

Documenting the quality of emergency dispatch centres handling of emergency calls regarding intoxicated unconscious patients.

METHODS

Interview with eight emergency dispatch centre directors and a nationwide survey among 313 dispatchers in Norway were performed. In addition, a customized scoring system was used to evaluate dispatcher log recordings of real cases. The recordings were compared with information from corresponding ambulance records.

RESULTS

Ninety-nine percent of the dispatchers stated that they used the Norwegian protocol for medical emergencies and 89% of them found it useful. The interviews, the survey, and the recordings, however, documented frequent deviation from the protocol. This instructs ambulance dispatch for any unconscious patient, but 21% stated that they would not dispatch any resource for an unconscious patient without further survey in alcohol-related cases. This was significantly more often (P<0.05) than for the narcotic, combination and prescription - drug-related cases with 4, 10 and 7%, respectively. The recordings revealed deviation from the protocol with dispatchers only determining the patients' level of consciousness and respiratory status in 64 and 70% of the cases, respectively. For 16% of the cases, the dispatcher did not ask the caller about consciousness at all, even though these patients later were found with reduced consciousness.

CONCLUSION

On the basis of the interviews and the survey, cases were handled according to guidelines. The log recordings, however, disclosed deviation from the protocol. Alcohol intoxication was associated with higher rate of deviation from the protocol compared with other intoxications.

Ventricular fibrillation in King County, Washington: a 30-year perspective

AIM

We determined the effect of four major program changes over a 30-year period on survival from witnessed cardiac arrest (CA) with ventricular fibrillation (VF) as the rhythm causing collapse.

METHODS

We conducted an investigation of emergency medical services (EMS)-treated CA occurring between 1978 and 2007. Data were obtained from a registry maintained by the King County Emergency Medical Services Division. Using Utstein style definitions, we measured changes in patient survival in light of four programs that were implemented during the span of the study: defibrillation by emergency medical technicians (EMTs), dispatcher-assisted cardiopulmonary resuscitation (CPR), public access defibrillation, and a CPR-defibrillation protocol that replaced delivery of three sequential shocks with administration of one shock followed by 2 min of CPR.

RESULTS

Overall survival from witnessed VF during the study period was 34%. While demographic characteristics of patients in CA remained constant, we observed greater rates of survival in the years following the program changes, 1983-2006, compared to survival in the period before the changes, 1977-1982. The greatest increase in survival occurred following the CPR-defibrillation protocol change in 2005.

CONCLUSION

Despite adverse temporal trends, the four program changes appear to have contributed to increasing survival rates from out-of-hospital cardiac arrests in King County.

Evaluation of emergency medical dispatch in out-of-hospital cardiac arrest in Taipei

INTRODUCTION

Emergency medical dispatchers are the entry points to the emergency medical services (EMS). The overall performances of the dispatchers are imperative determinants of the emergency medical services dispatching system. There is little data on the cultural and language impacts on emergency medical dispatch.

OBJECTIVE

This study examined the emotional content and cooperation score (ECCS) among Mandarin Chinese speaking callers for cardiac arrests, and evaluated the performances of emergency medical services dispatching system in Taipei.

METHODS

This retrospective, observational study examined dispatching audio recordings obtained from the Taipei City Fire Department Dispatching Center between January 2004 to April 2004. The tapes of call relating to adult (age >or=18 years), non-traumatic cases with a presumed or field diagnosis of out-of-hospital cardiac arrest (OHCA) underwent systemic review. The caller's ECCS and the dispatcher's performances, including interview skills, provision of telephone-assisted cardiopulmonary resuscitation (T-CPR), and dispatcher's ability to identify OHCA were examined. Interrater reliability for determining ECCS and interview skills were assessed using kappa statistic.

RESULTS

A total of 199 audio recordings were reviewed. A mean ECCS of 1.42+/-0.64 (95% CI: 1.33-1.51) demonstrated that most callers were emotionally stable and cooperative when calling for help, even when facing cardiac arrest patients. There was a good association between ECCS and the sex of the callers (male 1.32 versus female 1.49; p<0.05). In 82% of interviews, the interview skills of the dispatchers was high (4 or 5 points); while in one fifth the interview skills were suboptimal. About one third of the cases were provided with T-CPR by the dispatchers. The sensitivity and positive predictive value (PPV) for predicting OHCA by dispatchers were 96.9% and 97.9%, respectively. A kappa value of 0.65 and 0.68 were obtained for the interrater reliability of ECCS and interview skills.

CONCLUSION

Most callers were found to be emotional stable and cooperative with dispatcher's interrogations when calling for cardiac arrest victims in this Mandarin speaking population. The dispatchers have shown satisfactory interview skills in approaching emergency calls and a good ability to identify OHCA. There is a low rate of T-CPR offered to the callers in the investigation. Efforts should be made to address the deficiencies in order to maximise the function of the EMS.

A prospective manikin-based observational study of telephone-directed cardiopulmonary resuscitation

INTRODUCTION

Bystander cardiopulmonary resuscitation (CPR) significantly improves the outcome from sudden cardiac arrest (SCA) and is therefore encouraged by offering telephone instructions to the bystander. The effectiveness of this technique was examined in a manikin-based study.

METHODS

Subjects performed CPR on an instrumented adult manikin by following Advanced Medical Priority Dispatch System v11.1 (AMPDS) instructions given by telephone from a different room.

RESULTS

Fifty-one volunteers (26 males, median age 56, range 27-76 years) with no previous experience of CPR were recruited. No volunteers followed the entire instructions correctly. Forty percent were unable to open the airway, only 18% achieved a median inspiration time of 2 s or greater and only 30% delivered tidal volumes within the range 700-1000 ml. Chest compressions were performed at a median rate of 52 min-1 with only 4% of subjects achieving a rate of 100 min-1. Depth of compression was also inadequate in 88% of subjects and hand positioning was incorrect in a third of subjects. The median duty cycle was 46% and there were significant delays between the commencement of the AMPDS protocol and the delivery of the first breath (123 s) and first chest compression (163 s).

DISCUSSION

Few bystanders perform CPR satisfactorily and further work is necessary to improve the effectiveness of telephone CPR instructions.

Evaluation of telephone CPR advice for adult cardiac arrest patients

INTRODUCTION

Telephone cardiopulmonary resuscitation (CPR) advice aims to increase the quality and quantity of bystander CPR, one of the few interventions shown to improve outcome in cardiac arrest. We evaluated a current telephone protocol (based on 2000 ILCOR guidelines) to assess the effectiveness of verbal CPR instructions.

METHODS

Emergency calls were identified from AMPDS codes for cardiac arrest and checked against the ambulance patient record form to confirm the diagnosis. Calls over a seven month period were analysed retrospectively, and the time taken to perform interventions calculated.

RESULTS

176 calls were analysed; of those 145 (82.4%) were confirmed cases of cardiac arrest. CPR was already underway in 11 cases (7.5%), 101 callers (69.7%) agreed to attempt CPR with telephone instructions. The median time to open the airway was 128s (62-482s), to perform the first ventilation was 247s (80-633s), and to perform the first chest compression was 315s (153-750s). Of those attempting CPR, 21 (20.8%) stopped because they were unable to move the patient onto a hard surface, and 28 (27.7%) required multiple attempts to perform effective ventilations. In the telephone CPR group 42/101 (40.6%) did not receive any chest compressions before the arrival of the ambulance crew.

CONCLUSIONS

Although current telephone-CPR instructions significantly improve the numbers of patients in whom bystander CPR is attempted, significant delays and poor quality CPR are likely to limit any benefits.

Effect of protocol compliance to cardiac arrest identification by emergency medical dispatchers

OBJECTIVES

The objective of the study was to assess the effect of protocol compliance to the accuracy of cardiac arrest (CA) identification by the dispatchers.

METHODS

The study was conducted prospectively over a 1-year period in 1996. The calls categorized as non-traumatic CAs by the dispatcher and calls where the patient was in non-traumatic CA when ambulance crew arrived were included in the study. The data was collected from emergency call tape recordings and ambulance run sheets. The compliance to the protocol was defined as gathering information to two questions: (1) Is the patient awake or can she/he be awakened? and (2) Is she/he breathing normally?

RESULTS

The number of calls included in the study was 776 and the dispatchers identified 83% of the CAs. The protocol was adhered in 52.4% of calls, more often in witnessed than unwitnessed cases (72.3% versus 45.0%, P<0.001). In correctly identified CAs, the protocol compliance was 49.4%. The compliance was higher in cases of unidentified CAs (60.3%, P=0.0326) and in cases of wrongly identified as CAs (false positives, 61.9%, P=0.0276).

CONCLUSIONS

A high identification rate of CAs seems to be achievable despite poor protocol compliance by dispatchers.

Prehospital and emergency department care to preserve neurologic function during and following cardiopulmonary resuscitation

Considerable progress has been made in providing high-quality prehospital and emergency cardiac care for OHCA victims. The use of early CPR, early defibrillation, early ACLS, and state-of-the-art postresuscitation care offers the best promise for improved community survival and neurologic outcome statistics in the future. The NIH-sponsored Resuscitation Outcomes Consortium represents the largest governmentally sponsored effort of its kind that that will test the value of promising pharmacologic and device interventions on improving survival and neurologic outcome in OHCA patients.

Factors impeding dispatcher-assisted telephone cardiopulmonary resuscitation

STUDY OBJECTIVE

Dispatcher-assisted telephone cardiopulmonary resuscitation (CPR) instruction can increase the proportion of sudden cardiac arrest victims who receive bystander CPR and has been associated with improved survival. Most sudden cardiac arrest victims, however, do not receive bystander CPR. The study objective was to examine factors that may impede implementation of telephone CPR.

METHODS

We reviewed dispatcher audio recordings and emergency medical services reports for 404 cases of sudden cardiac arrest that occurred from July 1, 2000, to June 30, 2002, in the study county to assess the phase (1, instructions not offered; 2, instructions offered but declined; or 3, instructions offered and accepted but CPR not implemented) and specific factors within each phase that potentially impede telephone CPR.

RESULTS

Twenty-five percent (99/404) of victims received bystander CPR without dispatch assistance, 34% (139/404) received telephone CPR, and 41% (166/404) did not receive bystander CPR. Each phase of telephone CPR process impeded the implementation of CPR: (1) instructions not offered in 48% (80/166); (2) instructions offered but declined in 31% (52/166); and (3) instructions offered and accepted but CPR not implemented in 21% (34/166). During the first phase, telephone CPR was potentially impeded most frequently because the victim was reported to have signs of life (51/80, 64%); during the second and third phases, telephone CPR was most often impeded because of bystander physical limitation (32/86, 37%). Emotional distress, disease transmission, disagreeable victim characteristics, or medicolegal concerns uncommonly impeded telephone CPR (10/86, 12%).

CONCLUSION

Factors potentially impeding telephone CPR can be identified. Although many are logistically challenging, some may be addressable and hence provide opportunities to strengthen the chain of survival.

To blow or not to blow: a randomised controlled trial of compression-only and standard telephone CPR instructions in simulated cardiac arrest

This randomised controlled trial used a manikin model of cardiac arrest to compare skill performance in untrained lay persons randomised to receive either compression-only telephone CPR (Compression-only tel., n=29) or standard telephone CPR instructions (Standard tel., n=30). Performance was evaluated during standardised 10 min cardiac arrest simulations using a video recording and data from a laptop computer connected to the training manikin. A number of subjects in both groups did not open the airway. More than 75% in the Standard tel. group failed to deliver two effective initial rescue breaths, and only 17% provided an adequate inflation volume for subsequent breaths, delivering a median of only five inflations during the entire scenario. Most subjects in both groups gave chest compressions that were too shallow and at an inappropriately rapid rate. Hand position was also poor, but was worse in the group given simplified instructions. There was a significant delay to first compression in both groups, although this interval was shortened by over a minute when ventilations were eliminated from the telephone instruction algorithm (245 vs. 184 s, P<0.001). Over two-and-a-half times as many chest compressions were delivered during an average ambulance response time with compression-only telephone directions compared with standard CPR (461 vs. 186, P<0.001). These variables may be critical in predicting survival from out-of-hospital cardiac arrest. Further research is necessary to establish if modifications to scripted telephone instructions can remedy the identified performance deficiencies. Eliminating instructions for rescue breaths from scripted telephone directions will have little impact on the ventilation of most patients. Research is required to determine if the consequent reduction in the delay to starting chest compressions and the significant increase in the number of compressions delivered can increase survival from out-of-hospital cardiac arrest.