Resuscitation Outcomes Consortium (ROC) Prehospital Resuscitation Using an Impedance Valve

This study has been terminated.
(Terminated because preliminary data suggested no difference in the strategies.)
Sponsor:
Collaborators:
Canadian Institutes of Health Research (CIHR)
Defence Research and Development Canada
Heart and Stroke Foundation of Canada
American Heart Association
Information provided by (Responsible Party):
Susanne May, University of Washington
ClinicalTrials.gov Identifier:
NCT00394706
First received: October 30, 2006
Last updated: April 26, 2012
Last verified: April 2012
Results First Received: March 23, 2012  
Study Type: Interventional
Study Design: Allocation: Randomized;   Endpoint Classification: Efficacy Study;   Intervention Model: Factorial Assignment;   Masking: Double Blind (Subject, Caregiver, Investigator);   Primary Purpose: Treatment
Condition: Heart Arrest
Interventions: Device: Impedance Threshold Device (ITD)
Device: Sham ITD
Other: Analyze early
Other: Analyze later

  Participant Flow
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Recruitment Details
Key information relevant to the recruitment process for the overall study, such as dates of the recruitment period and locations
Clinical sites enrolled patients during a run-in period with the first patient enrolled on June 7, 2007. The run-in period ranged from from 2 to 6 months across the sites. The last patient was enrolled in the evaluable phase on November 6, 2009. All patients were enrolled in the pre-hospital EMS setting.

Pre-Assignment Details
Significant events and approaches for the overall study following participant enrollment, but prior to group assignment
No text entered.

Reporting Groups
  Description
Analyze Early + ITD Analyze early: upon EMS (emergency medical services) arrival at the scene of a non-traumatic cardiac arrest, the EMS providers assess the cardiac rhythm as soon as possible. Approximately thirty seconds of CPR (cardiopulmonary resuscitation) may be done prior to an assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Use of ITD (Impedance Threshold Device) by EMS providers in the prehospital setting.
Analyze Early + Sham Analyze early: upon EMS arrival at the scene of a non-traumatic cardiac arrest, the EMS providers assess the cardiac rhythm as soon as possible. Approximately thirty seconds of CPR may be done prior to an assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Use of a sham ITD by EMS providers in the pre-hospital setting.
Analyze Early, Not in ITD vs Sham Analyze early. Upon EMS arrival at the scene of a non-traumatic cardiac arrest, the EMS providers assess the cardiac rhythm as soon as possible. Approximately thirty seconds of CPR may be done prior to an assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Neither an ITD nor sham device used.
Analyze Later + ITD Analyze later: upon the EMS arrival at the scene of a non-traumatic cardiac arrest, three minutes of CPR is done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Use of Impedance Threshold Device by EMS providers in the pre-hospital setting.
Analyze Later + Sham Analyze later: upon the EMS arrival at the scene of a non-traumatic cardiac arrest, three minutes of CPR is done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Use of a sham ITD by EMS providers in the pre-hospital setting.
Analyze Later, Not in ITD vs. Sham Analyze later: upon the EMS arrival at the scene of a non-traumatic cardiac arrest, three minutes of CPR is done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Neither an ITD nor sham device used.
Not in AEvAL, ITD Device Upon the EMS arrival at the scene of a non-traumatic cardiac arrest, local policy determines the length of CPR done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Impedance Threshold Device used by EMS providers in the pre-hospital setting.
Not in AEvAL, Sham Upon the EMS arrival at the scene of a non-traumatic cardiac arrest, local policy determines the length of CPR done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Sham ITD used by EMS providers in the pre-hospital setting.

Participant Flow:   Overall Study
    Analyze Early + ITD     Analyze Early + Sham     Analyze Early, Not in ITD vs Sham     Analyze Later + ITD     Analyze Later + Sham     Analyze Later, Not in ITD vs. Sham     Not in AEvAL, ITD Device     Not in AEvAL, Sham  
STARTED     1819     1862     1624     1633     1636     1384     929     851  
COMPLETED     1815     1860     1615     1632     1634     1377     926     851  
NOT COMPLETED     4     2     9     1     2     7     3     0  
Withdrawal by Subject                 2                 0                 1                 0                 0                 2                 1                 0  
Lost to Follow-up                 2                 2                 8                 1                 2                 5                 2                 0  



  Baseline Characteristics
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Population Description
Explanation of how the number of participants for analysis was determined. Includes whether analysis was per protocol, intention to treat, or another method. Also provides relevant details such as imputation technique, as appropriate.
No text entered.

Reporting Groups
  Description
Analyze Early + ITD Analyze early: upon EMS (emergency medical services) arrival at the scene of a non-traumatic cardiac arrest, the EMS providers assess the cardiac rhythm as soon as possible. Approximately thirty seconds of CPR (cardiopulmonary resuscitation) may be done prior to an assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Use of ITD (Impedance Threshold Device) by EMS providers in the prehospital setting.
Analyze Early + Sham Analyze early: upon EMS arrival at the scene of a non-traumatic cardiac arrest, the EMS providers assess the cardiac rhythm as soon as possible. Approximately thirty seconds of CPR may be done prior to an assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Use of a sham ITD by EMS providers in the pre-hospital setting.
Analyze Early, Not in ITD vs Sham Analyze early. Upon EMS arrival at the scene of a non-traumatic cardiac arrest, the EMS providers assess the cardiac rhythm as soon as possible. Approximately thirty seconds of CPR may be done prior to an assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Neither an ITD nor sham device used.
Analyze Later + ITD Analyze later: upon the EMS arrival at the scene of a non-traumatic cardiac arrest, three minutes of CPR is done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Use of Impedance Threshold Device by EMS providers in the pre-hospital setting.
Analyze Later + Sham Analyze later: upon the EMS arrival at the scene of a non-traumatic cardiac arrest, three minutes of CPR is done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Use of a sham ITD by EMS providers in the pre-hospital setting.
Analyze Later, Not in ITD vs. Sham Analyze later: upon the EMS arrival at the scene of a non-traumatic cardiac arrest, three minutes of CPR is done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Neither an ITD nor sham device used.
Not in AEvAL, ITD Device Upon the EMS arrival at the scene of a non-traumatic cardiac arrest, local policy determines the length of CPR done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Impedance Threshold Device used by EMS providers in the pre-hospital setting.
Not in AEvAL, Sham Upon the EMS arrival at the scene of a non-traumatic cardiac arrest, local policy determines the length of CPR done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required. Sham ITD used by EMS providers in the pre-hospital setting.
Total Total of all reporting groups

Baseline Measures
    Analyze Early + ITD     Analyze Early + Sham     Analyze Early, Not in ITD vs Sham     Analyze Later + ITD     Analyze Later + Sham     Analyze Later, Not in ITD vs. Sham     Not in AEvAL, ITD Device     Not in AEvAL, Sham     Total  
Number of Participants  
[units: participants]
  1817     1861     1621     1631     1633     1379     929     851     11722  
Age [1]
[units: participants]
                 
<=18 years     1     2     2     1     4     0     1     0     11  
Between 18 and 65 years     734     809     687     693     675     590     381     370     4939  
>=65 years     1082     1050     932     937     954     789     547     481     6772  
Age [1]
[units: years]
Mean ± Standard Deviation
  67.3  ± 16.3     66.6  ± 16.4     66.3  ± 17.0     67.2  ± 16.6     67.1  ± 16.4     66.3  ± 16.7     67.7  ± 16.3     66.7  ± 16.7     66.9  ± 16.6  
Gender [2]
[units: participants]
                 
Female     609     673     605     615     578     486     313     303     4182  
Male     1208     1188     1016     1016     1055     893     616     548     7540  
Region of Enrollment  
[units: participants]
                 
United States     733     764     411     691     698     400     534     489     4720  
Canada     1084     1097     1210     940     935     979     395     362     7002  
[1] Age is not available for 8 ITD, 8 Sham, 11 Analyze Early, and 18 Analyze Later subjects.
[2] Gender missing for one ITD and one analyze earlier subject.



  Outcome Measures
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1.  Primary:   Survival to Hospital Discharge With Satisfactory Function (Modified Rankin Scale [MRS] of Less Than or Equal to 3).   [ Time Frame: Hospital discharge or death prior to discharge ]
  Hide Outcome Measure 1

Measure Type Primary
Measure Title Survival to Hospital Discharge With Satisfactory Function (Modified Rankin Scale [MRS] of Less Than or Equal to 3).
Measure Description The modified Rankin Score (mRS) measures the ability of patients to function independently. The scale goes from 0 (no symptoms) to 6 (death). Subjects with a mRS scores of three or less (i.e. better) at the time of hospital discharge were considered to have a positive outcome, resulting in a binary measure.
Time Frame Hospital discharge or death prior to discharge  
Safety Issue Yes  

Population Description
Explanation of how the number of participants for analysis was determined. Includes whether analysis was per protocol, intention to treat, or another method. Also provides relevant details such as imputation technique, as appropriate.
Analyses of both interventions excluded subjects who suffered arrest secondary to drowning, strangulation, or electrocution; or for whom the primary outcome was unknown. Additionally, the ITD vs. Sham analysis excluded subjects who did not have the device applied, had study exclusions, or who had a response time of more than 15 minutes.

Reporting Groups
  Description
Analyze Early Analyze early: upon EMS (emergency medical services) arrival at the scene of a non-traumatic cardiac arrest, the EMS providers assess the cardiac rhythm as soon as possible. Approximately thirty seconds of CPR may be done prior to an assessment of the cardiac rhythm to determine whether a defibrillatory shock is required.
Analyze Later Analyze later: upon the EMS arrival at the scene of a non-traumatic cardiac arrest, three minutes of CPR is done prior to the assessment of the cardiac rhythm to determine whether a defibrillatory shock is required.
Active ITD Use of Impedance Threshold Device by EMS providers in the pre-hospital setting.
Sham ITD Sham ITD used by EMS providers in the pre-hospital setting.

Measured Values
    Analyze Early     Analyze Later     Active ITD     Sham ITD  
Number of Participants Analyzed  
[units: participants]
  5290     4643     4373     4345  
Survival to Hospital Discharge With Satisfactory Function (Modified Rankin Scale [MRS] of Less Than or Equal to 3).  
[units: participants]
  310     273     254     260  


Statistical Analysis 1 for Survival to Hospital Discharge With Satisfactory Function (Modified Rankin Scale [MRS] of Less Than or Equal to 3).
Groups [1] Analyze Early vs. Analyze Later
Method [2] Mixed Models Analysis
P Value [3] 0.59
Risk Difference (RD) [4] -0.2
95% Confidence Interval ( -1.1 to 0.7 )
[1] Additional details about the analysis, such as null hypothesis and power calculation:
  Comparison of the rates of MRS <=3 in Analyze Early vs. Analyze Later arms using a linear mixed effect model with an identity link and random effects to account for the cluster randomization.
[2] Other relevant method information, such as adjustments or degrees of freedom:
  No text entered.
[3] Additional information, such as whether or not the p-value is adjusted for multiple comparisons and the a priori threshold for statistical significance:
  Two sided test with an a priori threshold of 0.05 for declaring statistical significance.
[4] Other relevant estimation information:
  Estimate of the rate of MRS <= 3 in Analyze Later arm minus rate in Analyze early arm.

Statistical Analysis 2 for Survival to Hospital Discharge With Satisfactory Function (Modified Rankin Scale [MRS] of Less Than or Equal to 3).
Groups [1] Active ITD vs. Sham ITD
Method [2] t-test, 2 sided
P Value [3] 0.71
Risk Difference (RD) [4] -0.1
95% Confidence Interval ( -1.1 to 0.8 )
[1] Additional details about the analysis, such as null hypothesis and power calculation:
  Comparison of the rates of MRS <=3 in Active ITD and Sham treatment arms, adjusted for sequential monitoring.
[2] Other relevant method information, such as adjustments or degrees of freedom:
  No text entered.
[3] Additional information, such as whether or not the p-value is adjusted for multiple comparisons and the a priori threshold for statistical significance:
  To adjust for group sequential monitoring, the point estimate was bias-adjusted (Whitehead 1986) and confidence intervals and P values calculated from the maximum likelihood based ordering of the outcome(Emerson and Fleming, 1990)
[4] Other relevant estimation information:
  Estimate of the rate of MRS <= 3 in the active ITD arm minus the rate in the Sham ITD arm.



2.  Secondary:   Survival to Hospital Discharge   [ Time Frame: Survival to hospital discharge or death before discharge ]

3.  Secondary:   Modified Rankin Score at 6 Months After Hospital Discharge   [ Time Frame: 6 months post hospital discharge ]
Results not yet posted.   Anticipated Posting Date:   No text entered.   Safety Issue:   Yes

4.  Secondary:   Adult Lifestyle and Function Version of Mini-Mental Status Exam at 6 Months   [ Time Frame: 6 months post hospital discharge ]
Results not yet posted.   Anticipated Posting Date:   No text entered.   Safety Issue:   Yes

5.  Secondary:   Health Utilities Index III Score and Geriatric Depression Scale Score 6 Months   [ Time Frame: 6 months post hospital discharge ]
Results not yet posted.   Anticipated Posting Date:   No text entered.   Safety Issue:   Yes


  Serious Adverse Events


  Other Adverse Events


  More Information
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Certain Agreements:  
All Principal Investigators ARE employed by the organization sponsoring the study.


Limitations and Caveats
Limitations of the study, such as early termination leading to small numbers of participants analyzed and technical problems with measurement leading to unreliable or uninterpretable data
No text entered.  


Results Point of Contact:  
Name/Title: Siobhan Brown, PhD-Biostatistician
Organization: University of Washington
phone: 206-685-1302
e-mail: spes@uw.edu


Publications:
Aufderheide TP, Nichol G, Rea TD, Brown SP, Leroux BG, Pepe PE, Kudenchuk PJ, Christenson J, Daya MR, Dorian P, Callaway CW, Idris AH, Andrusiek D, Stephens SW, Hostler D, Davis DP, Dunford JV, Pirrallo RG, Stiell IG, Clement CM, Craig A, Van Ottingham L, Schmidt TA, Wang HE, Weisfeldt ML, Ornato JP, Sopko G, ROC Investigators. A trial of an impedance threshold device in out-of-hospital cardiac arrest. New England Journal of Medicine 2011; 365:798-806

Publications automatically indexed to this study:

Responsible Party: Susanne May, University of Washington
ClinicalTrials.gov Identifier: NCT00394706     History of Changes
Other Study ID Numbers: 29919-A, HL077863
Study First Received: October 30, 2006
Results First Received: March 23, 2012
Last Updated: April 26, 2012
Health Authority: United States: Food and Drug Administration
United States: Institutional Review Board