Effectiveness of Dispatch-Assisted Cardiopulmonary Resuscitation (CPR) Instructions

Effectiveness of Dispatch-Assisted Cardiopulmonary Resuscitation (CPR) Instructions: An Evaluation of 9-1-1 Calls.

The overall goal of this study is to better understand the factors leading to successful dispatch-assisted CPR instructions and to ultimately save the lives of more cardiac arrest patients. Specific objectives are to: 1) Determine the ability of 9-1-1 dispatchers to make the diagnosis of cardiac arrest over the phone; 2) Quantify the frequency and impact of perceived agonal breathing on cardiac arrest diagnosis; 3) Measure the frequency with which dispatch-assisted CPR instructions can be successfully completed in out-of-hospital cardiac arrest cases; and 4) Measure the impact of dispatch-assisted CPR instructions on bystander CPR and survival rates for out-of-hospital cardiac arrest.

Study Overview

• Status: Completed
• Conditions: Cardiac Arrest
• Intervention / Treatment: Behavioral: Dispatch-assisted CPR Instructions

Detailed Description

Background: Cardiac arrest is the leading cause of mortality in Canada, and the overall survival rate for out-of-hospital cardiac arrest rarely exceeds 5%. Survivors have a quality of life similar to the general population. While bystander CPR can increase survival for cardiac arrest victims up to four times, bystander CPR rates remain low in Canada (15%). Many Canadian urban communities offer 9-1-1 dispatch-assisted CPR instructions to callers reporting a victim in cardiac arrest. Some evidence suggests that agonal breathing can be misinterpreted as a sign of life by Dispatch Officers, resulting in the inappropriate withholding of dispatch-assisted CPR instructions. Dispatch-assisted CPR instructions are recommended by the International Guidelines on Emergency Cardiovascular Care, but their ability to improve cardiac arrest survival remains unclear according to a systematic review of the literature.

Objectives: The overall goal of this study is to better understand the factors leading to successful dispatch-assisted CPR instructions and to ultimately save more lives of cardiac arrest patients. Specific objectives are to: 1) Determine the ability of 9-1-1 dispatchers to make the diagnosis of cardiac arrest over the phone; 2) Quantify the frequency and impact of perceived agonal breathing on cardiac arrest diagnosis; 3) Measure the frequency with which dispatch-assisted CPR instructions can be successfully completed in out-of-hospital cardiac arrest cases; and 4) Measure the impact of dispatch-assisted CPR instructions on bystander CPR and survival rates for out-of-hospital cardiac arrest.

Methods: We will conduct a before-after, prospective cohort study that evaluates 9-1-1 call reporting for out-of-hospital cardiac arrest victims. The study will take place in 19 urban communities in Ontario providing dispatch-assisted CPR instructions since April 1st 2004. The study population will include all 9-1-1 callers reporting out-of-hospital cardiac arrests for which resuscitation was attempted in patients 16-years or older. The dispatch center protocol consists of establishing the nature of the emergency before initiating the appropriate level of response; this includes asking standardized questions to determine if cardiac arrest is present. The Dispatch Officer then offers CPR instructions over the telephone while emergency response vehicles are on their way to the location. Standardized data collection tools will be used to extract information from: 9-1-1 call recordings, paramedic patient care reports, base hospital records, fire medical records, and hospital medical records. All participating centers already combine information from various sources in a cardiac arrest registry. The following information will be collected: confirmation of cardiac arrest status by the Dispatch Officer, presence of apparent agonal breathing, CPR instructions offered to the 9-1-1 callers, factors influencing the ability of 9-1-1 callers to perform CPR including their proximity to the victim's location and their emotional receptiveness to instructions, the time interval between the call to 9-1-1 and the initiation of CPR by the bystander. Measurements will include the accuracy of cardiac arrest diagnosis, the frequency of perceived agonal breathing during cardiac arrest, 9-1-1 caller's ability to receive instructions and initiate CPR, bystander CPR rates, and survival to hospital discharge. Data analysis for Objective #1 will include sensitivity, specificity and receiver operating characteristic curve; Objectives #2 and #3 will be analyzed using descriptive statistics; and for Objective #4 univariate, stepwise logistic regression, and time series analysis will be performed to control for trends over time and variables otherwise associated with bystander CPR and survival rates in 6000 arrest victims.

• Study Type: Observational
• Enrollment (Actual): 2260

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Ottawa, Ontario, Canada, K1Y 4E9
      • Ottawa Hospital Research Institute

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients with out-of-hospital cardiac arrest

Description

Inclusion Criteria:

All patients with out-of-hospital cardiac arrest (absence of a detectable pulse, unresponsiveness, and apnea) that are:

• Of presumed cardiac origin;
• Occurring in our study communities; and
• For which resuscitation is attempted by a bystander and/or the emergency responders; or for which dispatch-assisted CPR instructions are being provided.

Exclusion Criteria:

The following patients will be excluded:

• Patients younger than 16 years;
• Patients who are "obviously dead" as defined by the Ambulance Act of Ontario (decomposition, rigor mortis, decapitation, or other);
• Trauma victims, including hanging and burns; or
• Patients with cardiac arrests clearly of other non-cardiac origin including drug overdose, carbon monoxide poisoning, drowning, exsanguination, electrocution, asphyxia, hypoxia related to respiratory disease, cerebrovascular accident and documented terminal illness.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Potential cardiac arrest calls; All 9-1-1 calls for unconscious patients will be included over the timeframe January 2008 and October 2009 in the participating communities to determine cardiac arrest diagnostic accuracy by 9-1-1 call takers

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Sensitivity	Number of true cardiac arrest cases correctly identified	At time of 9-1-1 call

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Specificity	Number of cases not in cardiac arrest identified correctly (true negative)	At time of 9-1-1 call

Collaborators and Investigators

• Sponsor: Ottawa Hospital Research Institute
• Collaborators: Canadian Institutes of Health Research (CIHR)
• Investigators: Principal Investigator: Christian Vaillancourt, MD, OHRI

Publications and helpful links

General Publications

• Vaillancourt C, Charette M, Kasaboski A, Hoad M, Larocque V, Crete D, Logan S, Lamoureux P, McBride J, Cheskes S, Wells GA, Stiell IG. Cardiac arrest diagnostic accuracy of 9-1-1 dispatchers: a prospective multi-center study. Resuscitation. 2015 May;90:116-20. doi: 10.1016/j.resuscitation.2015.02.027. Epub 2015 Mar 9.
• Vaillancourt C, Charette ML, Stiell IG, Wells GA. An evaluation of 9-1-1 calls to assess the effectiveness of dispatch-assisted cardiopulmonary resuscitation (CPR) instructions: design and methodology. BMC Emerg Med. 2008 Nov 5;8:12. doi: 10.1186/1471-227X-8-12.

Study record dates

Study Major Dates

• Study Start: July 1, 2007
• Primary Completion (Actual): June 1, 2010
• Study Completion (Actual): December 1, 2010

Study Registration Dates

• First Submitted: April 21, 2008
• First Submitted That Met QC Criteria: April 22, 2008
• First Posted (Estimated): April 23, 2008

Study Record Updates

• Last Update Posted (Actual): September 19, 2024
• Last Update Submitted That Met QC Criteria: April 26, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Keywords: CPR; cardiac arrest; resuscitation; bystander CPR; dispatch-assisted CPR
• Additional Relevant MeSH Terms: Heart Diseases; Cardiovascular Diseases; Heart Arrest
• Other Study ID Numbers: 2007233-01H