An evaluation of 9-1-1 calls to assess the effectiveness of dispatch-assisted cardiopulmonary resuscitation (CPR) instructions: design and methodology.
Cardiac arrest is the leading cause of mortality in Canada, and the overall survival rate for out-of-hospital cardiac arrest rarely exceeds 5%. Bystander cardiopulmonary resuscitation (CPR) has been shown to increase survival for cardiac arrest victims. However, bystander CPR rates remain low in Canada, rarely exceeding 15%, despite various attempts to improve them. Dispatch-assisted CPR instructions have the potential to improve rates of bystander CPR and many Canadian urban communities now offer instructions to callers reporting a victim in cardiac arrest. Dispatch-assisted CPR instructions are recommended by the International Guidelines on Emergency Cardiovascular Care, but their ability to improve cardiac arrest survival remains unclear.
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. The study will utilize a before-after, prospective cohort design to specifically: 1) Determine the ability of 9-1-1 dispatchers to correctly diagnose cardiac arrest; 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; and 4) Measure the impact of dispatch-assisted CPR instructions on bystander CPR and survival rates.The study will be conducted in 19 urban communities in Ontario, Canada. All 9-1-1 calls occurring in the study communities reporting out-of-hospital cardiac arrest in victims 16 years of age or older for which resuscitation was attempted will be eligible. Information will be obtained from 9-1-1 call recordings, paramedic patient care reports, base hospital records, fire medical records and hospital medical records. Victim, caller and system characteristics will be measured in the study communities before the introduction of dispatch-assisted CPR instructions (before group), during the introduction (run-in phase), and following the introduction (after group).
The study will obtain information essential to the development of clinical trials that will test a variety of educational approaches and delivery methods for telephone cardiopulmonary resuscitation instructions. This will be the first study in the world to clearly quantify the impact of dispatch-assisted CPR instructions on survival to hospital discharge for out-of-hospital cardiac arrest victims.
ClinicalTrials.gov NCT00664443.
Notes
Cites: J Fam Pract. 1983 Mar;16(3):561-66827234
Cites: J Med Educ. 1983 Jul;58(7):568-756864745
Cites: Ann Emerg Med. 1983 Aug;12(8):482-46881644
Cites: Ann Emerg Med. 1984 Feb;13(2):118-216691613
Cites: Ann Emerg Med. 1984 Sep;13(9 Pt 1):701-46465651
Regionalized trauma systems have been shown repeatedly to improve the outcome of seriously injured patients. However, we do not have data regarding which components of these systems have the most impact on outcome and to what degree. The objective of this study was to understand the association between various components that make up a trauma system and outcome.
Surveys were administered to trauma directors at 59 hospitals in the province of Quebec, Canada. Data from the surveys were then linked with specific outcome variables obtained from a regionalized trauma database. Specific outcomes were assigned to trauma system- and in-hospital-based components after controlling for injury severity.
Over 4.8 years, 72,073 patients met inclusion criteria. Components found to affect survival after risk adjustment were prehospital notification (OR, 0.61; 95% CI, 0.39-0.94) and the presence of a performance improvement program in that hospital (OR, 0.44; 95% CI, 0.20-0.94). Increased patient volume was associated with a reduction in risk-adjusted mortality (OR, 0.98; 95% CI, 0.97-0.99). Tertiary trauma centers were also associated with a reduction in risk-adjusted mortality compared with both secondary and primary centers (OR, 0.68; 95% CI, 0.48-0.99).
Improvements in outcome in a regionalized trauma system are secondary to a combination of elements, as well as to the interplay of these elements on each other. Prehospital notification protocols and performance improvement programs appear to be most associated with decreased risk-adjusted odds of death.
The chance of surviving out-of-hospital cardiac arrest (OHCA) depends on early and correct recognition of cardiac arrest by the emergency medical dispatcher during the emergency call. When cardiac arrest is identified, telephone guided cardiopulmonary resuscitation (CPR) and referral to an automated external defibrillator should be initiated. Previous studies have investigated barriers to recognition of OHCA, and found the caller's description of sign of life, the type of caller, caller's emotional state, an inadequate dialogue during the emergency call, and patient's agonal breathing as influential factors. Though many of these factors are included in the algorithms used by medical dispatchers, many OHCA still remain not recognised. Qualitative studies investigating the communication between the caller and dispatcher are very scarce. There is a lack of knowledge about what influences the dispatchers' recognition of OHCA, focusing on the communication during the emergency call. The purpose of this study is to identify factors affecting medical dispatchers' recognition of OHCA during emergency calls in a qualitative analysis of calls.
An investigator triangulated inductive thematic analysis of recordings of out-of-hospital cardiac arrest emergency calls from December 2012. Participants were the callers (bystanders) and the emergency medical dispatchers. Data were analysed using a hermeneutic approach.
Based on the concept of data saturation, 13 recordings of not recognised cardiac arrest and 8 recordings of recognised cardiac arrests were analysed. Three main themes, six subthemes and an embedded theme emerged from the analysis: caller's physical distance (caller near patient, caller not near patient), caller's emotional distance (keeping calm, losing control), caller is a healthcare professional (responsibility is handed over to the caller, caller assumes responsibility), and the embedded theme: caller assesses the patient.
The physical and emotional proximity of the caller (bystander) as well as the caller's professional background affect the dispatcher's chances of correct recognition and handling of cardiac arrest. The dispatcher should acknowledge the triple roles of conducting patient assessment, instructing the caller, and reassuring the emotionally affected caller.
