Clinical Trial: SmartCPR Trial: An Analysis of a Waveform-Based Automated External Defibrillation (AED) Algorithm on Survival From Out-of-Hospital Ventricular Fibrillation

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: An International, Randomized, Controlled Prehospital Trial of a Waveform-Based Automated External Defibrillation Algorithm for the Management of Ventricular Fibrillation

Brief Summary: This study is designed to examine the impact of an available technology within an automated external defibrillator (AEDs) to improve survival following out-of-hospital cardiac arrest for patients presenting in ventricular fibrillation.

Detailed Summary:

The delivery of an electrical shock, termed defibrillation, has long been recognized as one of the critical "links" in the "Chain of Survival" following out-of-hospital cardiac arrest. This is particularly the case for patients who present in ventricular fibrillation (VF), a state of constant and yet uncoordinate firing of the lower portions of the heart (the ventricles), and the ability to treat these patients with defibrillation prior to their arrival in the hospital has remained one of the reasons why this group represents the patients who are most likely to survive an out-of-hospital cardiac arrest.

Though this technology has been successfully utilized in the prehospital setting for more than forty years, the long-held belief that "immediate defibrillation" was the optimal treatment for all patients has now come into question.

Following research done in locations such as Seattle, WA and Oslo, Norway, there came a recognition that some patients (particularly those who have been in cardiac arrest for 4-5 minutes prior to EMS arrival) may actually benefit from a period of CPR prior to defibrillation ("delayed defibrillation"). This has to do with the changes that take place within the heart and even at the level of the cells within the heart following the onset of VF. After several minutes of VF, the cells within the heart have been deprived and depleted of oxygen and other energy-containing molecules, and there has been a build-up of other substances such as acids and potassium. By providing CPR prior to defibrillation, it is thought that the patient's heart may be provided with enough oxygen and other energy-containing molecules, making it more likely that the heart will respond favorably to defibrillation.

Yet this is not necessar
Sponsor: New York City Fire Department

Current Primary Outcome: Survival to Hospital Discharge [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Survival to hospital admission [ Time Frame: within hours from the time of arrest ]
  • Return of spontaneous circulation (ROSC) in prehospital setting [ Time Frame: Variable (depends on EMS contact time) ]
  • Neurological status among survivors [ Time Frame: Variable (measured at hospital discharge) ]
  • Survival (defined as ROSC, survival to hospital admission, and survival to hospital discharge) as compared to a "delayed defibrillation" cohort in NYC [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Impact of CPR interval on VF waveform characteristics [ Time Frame: Immediately after CPR interval ]
  • Utility of AED algorithm and VF characteristics among EMS-witnessed arrests [ Time Frame: Variable (some immediate data, some depends upon interval needed for hospital admission and discharge) ]
  • Utility of this AED technology and VF characteristics among pediatric patients [ Time Frame: Variable (some immediate data, some depends upon interval needed for hospital admission and discharge) ]
  • Impact of bystander CPR on VF waveform characteristics [ Time Frame: Immediate (taken from data during arrest) ]
  • Comparison of EMS response times to VF waveform characteristics [ Time Frame: Immediate (data obtained during EMS response and arrest period) ]
  • Frequency of unmanageable airways in out-of-hospital cardiac arrest patients [ Time Frame: Immediate (measured at the time of arrest) ]
  • Impact of patient race upon the provision of bystander CPR, VF waveform characteristics, and survival [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Relationship between presenting and interval waveform capnography readings and survival [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Frequency of organ donation among out-of-hospital cardiac arrest patients transported to the hospital who do not survive to hospital discharge [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Waveform characteristics among patients presenting in secondary VF (initial presenting rhythm asystole or pulseless electrical activity) [ Time Frame: Immediate (derived from data collected during the arrest) ]
  • Description of and outcomes of patients for whom intraosseous access is utilized during the cardiac arrest [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Utstein comparison of two cities (London and New York) [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Impact of bystander CPR on survival as a function of response time [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Association between ambient small particle (PM2.5) pollution and cardiac arrest indicence in New York City [ Time Frame: To be determined by modelling ]


Original Secondary Outcome:

  • Survival to hospital admission [ Time Frame: within hours from the time of arrest ]
  • Return of spontaneous circulation (ROSC) in prehospital setting [ Time Frame: Variable (depends on EMS contact time) ]
  • Neurological status among survivors [ Time Frame: Variable (measured at hospital discharge) ]
  • Survival (defined as ROSC, survival to hospital admission, and survival to hospital discharge) as compared to a "delayed defibrillation" cohort in NYC [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Impact of CPR interval on VF waveform characteristics [ Time Frame: Immediately after CPR interval ]
  • Utility of AED algorithm and VF characteristics among EMS-witnessed arrests [ Time Frame: Variable (some immediate data, some depends upon interval needed for hospital admission and discharge) ]
  • Utility of this AED technology and VF characteristics among pediatric patients [ Time Frame: Variable (some immediate data, some depends upon interval needed for hospital admission and discharge) ]
  • Impact of bystander CPR on VF waveform characteristics [ Time Frame: Immediate (taken from data during arrest) ]
  • Comparison of EMS response times to VF waveform characteristics [ Time Frame: Immediate (data obtained during EMS response and arrest period) ]
  • Frequency of unmanageable airways in out-of-hospital cardiac arrest patients [ Time Frame: Immediate (measured at the time of arrest) ]
  • Impact of patient race upon the provision of bystander CPR, VF waveform characteristics, and survival [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Relationship between presenting and interval waveform capnography readings and survival [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Frequency of organ donation among out-of-hospital cardiac arrest patients transported to the hospital who do not survive to hospital discharge [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Waveform characteristics among patients presenting in secondary VF (initial presenting rhythm asystole or pulseless electrical activity) [ Time Frame: Immediate (derived from data collected during the arrest) ]
  • Description of and outcomes of patients for whom intraosseous access is utilized during the cardiac arrest [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Utstein comparison of two cities (London and New York) [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]
  • Impact of bystander CPR on survival as a function of response time [ Time Frame: Variable (depends upon interval needed for hospital admission and discharge) ]


Information By: New York City Fire Department

Dates:
Date Received: September 25, 2007
Date Started: May 2006
Date Completion:
Last Updated: October 18, 2009
Last Verified: October 2009