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

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ClinicalTrials.gov Identifier: NCT00394706
Recruitment Status : Terminated (Terminated because preliminary data suggested no difference in the strategies.)
First Posted : November 1, 2006
Results First Posted : April 18, 2012
Last Update Posted : August 9, 2018
Sponsor:
Collaborators:
National Heart, Lung, and Blood Institute (NHLBI)
National Institute of Neurological Disorders and Stroke (NINDS)
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

Study Type Interventional
Study Design Allocation: Randomized;   Intervention Model: Factorial Assignment;   Masking: Triple (Participant, Care Provider, Investigator);   Primary Purpose: Treatment
Condition Heart Arrest
Interventions Device: Impedance Threshold Device (ITD)
Device: Sham ITD
Other: Analyze early
Other: Analyze later
Enrollment 11738
Recruitment Details 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  
Arm/Group Title 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
Hide Arm/Group Description 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: 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. 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: 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: 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: 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. 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. 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.
Period Title: Overall Study
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
Reason Not Completed
Withdrawal by Subject             2             0             1             0             0             2             1             0
Lost to Follow-up             2             2             8             1             2             5             2             0
Arm/Group Title 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
Hide Arm/Group Description 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: 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. 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: 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: 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: 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. 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. 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 of all reporting groups
Overall Number of Baseline Participants 1817 1861 1621 1631 1633 1379 929 851 11722
Hide Baseline Analysis Population Description
[Not Specified]
Age, Categorical   [1] 
Measure Type: Count of Participants
Unit of measure:  Participants
Number Analyzed 1817 participants 1861 participants 1621 participants 1631 participants 1633 participants 1379 participants 929 participants 851 participants 11722 participants
<=18 years
1
   0.1%
2
   0.1%
2
   0.1%
1
   0.1%
4
   0.2%
0
   0.0%
1
   0.1%
0
   0.0%
11
   0.1%
Between 18 and 65 years
734
  40.4%
809
  43.5%
687
  42.4%
693
  42.5%
675
  41.3%
590
  42.8%
381
  41.0%
370
  43.5%
4939
  42.1%
>=65 years
1082
  59.5%
1050
  56.4%
932
  57.5%
937
  57.4%
954
  58.4%
789
  57.2%
547
  58.9%
481
  56.5%
6772
  57.8%
[1]
Measure Description: Age is not available for 8 ITD, 8 Sham, 11 Analyze Early, and 18 Analyze Later subjects.
Age, Continuous   [1] 
Mean (Standard Deviation)
Unit of measure:  Years
Number Analyzed 1817 participants 1861 participants 1621 participants 1631 participants 1633 participants 1379 participants 929 participants 851 participants 11722 participants
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)
[1]
Measure Description: Age is not available for 8 ITD, 8 Sham, 11 Analyze Early, and 18 Analyze Later subjects.
Sex: Female, Male   [1] 
Measure Type: Count of Participants
Unit of measure:  Participants
Number Analyzed 1817 participants 1861 participants 1621 participants 1631 participants 1633 participants 1379 participants 929 participants 851 participants 11722 participants
Female
609
  33.5%
673
  36.2%
605
  37.3%
615
  37.7%
578
  35.4%
486
  35.2%
313
  33.7%
303
  35.6%
4182
  35.7%
Male
1208
  66.5%
1188
  63.8%
1016
  62.7%
1016
  62.3%
1055
  64.6%
893
  64.8%
616
  66.3%
548
  64.4%
7540
  64.3%
[1]
Measure Description: Gender missing for one ITD and one analyze earlier subject.
Region of Enrollment  
Measure Type: Number
Unit of measure:  Participants
Number Analyzed 1817 participants 1861 participants 1621 participants 1631 participants 1633 participants 1379 participants 929 participants 851 participants 11722 participants
United States 733 764 411 691 698 400 534 489 4720
Canada 1084 1097 1210 940 935 979 395 362 7002
1.Primary Outcome
Title Survival to Hospital Discharge With Satisfactory Function (Modified Rankin Scale [MRS] of Less Than or Equal to 3).
Hide 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
Show Outcome Measure DataHide Outcome Measure Data
Hide Analysis Population Description
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.
Arm/Group Title Analyze Early Analyze Later Active ITD Sham ITD
Hide Arm/Group Description:
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: 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.
Sham ITD used by EMS providers in the pre-hospital setting.
Overall Number of Participants Analyzed 5290 4643 4373 4345
Measure Type: Number
Unit of Measure: participants
310 273 254 260
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Analyze Early, Analyze Later
Comments 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.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value 0.59
Comments Two sided test with an a priori threshold of 0.05 for declaring statistical significance.
Method Mixed Models Analysis
Comments [Not Specified]
Method of Estimation Estimation Parameter Risk Difference (RD)
Estimated Value -0.2
Confidence Interval (2-Sided) 95%
-1.1 to 0.7
Estimation Comments Estimate of the rate of MRS <= 3 in Analyze Later arm minus rate in Analyze early arm.
Show Statistical Analysis 2 Hide Statistical Analysis 2
Statistical Analysis Overview Comparison Group Selection Active ITD, Sham ITD
Comments Comparison of the rates of MRS <=3 in Active ITD and Sham treatment arms, adjusted for sequential monitoring.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value 0.71
Comments 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)
Method t-test, 2 sided
Comments [Not Specified]
Method of Estimation Estimation Parameter Risk Difference (RD)
Estimated Value -0.1
Confidence Interval (2-Sided) 95%
-1.1 to 0.8
Estimation Comments Estimate of the rate of MRS <= 3 in the active ITD arm minus the rate in the Sham ITD arm.
2.Secondary Outcome
Title Survival to Hospital Discharge
Hide Description [Not Specified]
Time Frame Survival to hospital discharge or death before discharge
Show Outcome Measure DataHide Outcome Measure Data
Hide Analysis Population Description
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.
Arm/Group Title Analyze Early Analyze Later Active ITD Sham ITD
Hide Arm/Group Description:
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: 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.
Sham ITD used by EMS providers in the pre-hospital setting.
Overall Number of Participants Analyzed 5290 4643 4373 4345
Measure Type: Number
Unit of Measure: participants
427 372 357 355
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Analyze Early, Analyze Later
Comments Comparison of the rates of survival to hospital discharge in Analyze Early vs. Analyze Later arms using a generalized estimating equations model with an identity link, grouping on cluster.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value 0.92
Comments Two sided test with an a priori threshold of 0.05 for declaring statistical significance.
Method GEE
Comments [Not Specified]
Method of Estimation Estimation Parameter Risk Difference (RD)
Estimated Value -0.1
Confidence Interval (2-Sided) 95%
-1.2 to 1.1
Estimation Comments Estimate of the rate of survival to hospital discharge in Analyze Later arm minus rate in Analyze early arm.
Show Statistical Analysis 2 Hide Statistical Analysis 2
Statistical Analysis Overview Comparison Group Selection Active ITD, Sham ITD
Comments Comparison of the rates of survival to hospital discharge in Active ITD and Sham treatment arms.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value 0.99
Comments [Not Specified]
Method t-test, 2 sided
Comments [Not Specified]
Method of Estimation Estimation Parameter Risk Difference (RD)
Estimated Value 0.0
Confidence Interval (2-Sided) 95%
-1.2 to 1.1
Estimation Comments Estimate of the rate of survival to hospital discharge in the active ITD arm minus rate in the Sham ITD arm.
3.Secondary Outcome
Title Modified Rankin Score at 6 Months After Hospital Discharge
Hide Description The modified Rankin Score (mRS) measures the ability of patients to function independently. The scale goes from 0 (no symptoms) to 6 (death).
Time Frame 6 months post hospital discharge
Show Outcome Measure DataHide Outcome Measure Data
Hide Analysis Population Description
ITT population, survived to hospital discharge, consented to participate in the post-discharge substudy, and with at least one post-discharge assessment.
Arm/Group Title Analyze Early Analyze Later Active ITD Sham ITD
Hide Arm/Group Description:
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: 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.
Sham ITD used by EMS providers in the pre-hospital setting.
Overall Number of Participants Analyzed 308 274 218 223
Mean (Standard Deviation)
Unit of Measure: units on a scale
1.7  (1.8) 1.8  (1.8) 1.8  (1.9) 1.6  (1.7)
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Analyze Early, Analyze Later
Comments Linear regression was used to assess associations between post-discharge measures and treatment group comparisons with adjustment for baseline characteristics. Site was adjusted for to accommodate clustering of patients within sites. All regression analyses used robust standard errors to accommodate non-constant variances.
Type of Statistical Test Superiority
Comments [Not Specified]
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value 0.07
Confidence Interval (2-Sided) 95%
-0.20 to 0.34
Estimation Comments Mean MRS for Analyze Later minus mean MRS for Analyze Early (i.e. positive values favor Analyze Later).
Show Statistical Analysis 2 Hide Statistical Analysis 2
Statistical Analysis Overview Comparison Group Selection Active ITD, Sham ITD
Comments Linear regression was used to assess associations between post-discharge measures and treatment group comparisons with adjustment for baseline characteristics. Site was adjusted for to accommodate clustering of patients within sites. All regression analyses used robust standard errors to accommodate non-constant variances.
Type of Statistical Test Superiority
Comments [Not Specified]
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value 0.14
Confidence Interval (2-Sided) 95%
-0.17 to 0.44
Estimation Comments Mean MRS for Active ITD minus mean MRS for Sham ITD (i.e. positive values favor the active device).
4.Secondary Outcome
Title Adult Lifestyle and Function Version of Mini-Mental Status Exam at 6 Months
Hide Description The adult lifestyle and function interview (ALFI) version of the mini-mental status exam (MMSE) measures neurological status. The ALFI-MMSE has 23 items. It is scored from 0 to 22, with lower scores interpreted as being worse.
Time Frame 6 months post hospital discharge
Show Outcome Measure DataHide Outcome Measure Data
Hide Analysis Population Description
ITT population, survived to hospital discharge, consented to participate in the post-discharge substudy, and with at least one post-discharge assessment.
Arm/Group Title Analyze Early Analyze Later Active ITD Sham ITD
Hide Arm/Group Description:
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: 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.
Sham ITD used by EMS providers in the pre-hospital setting.
Overall Number of Participants Analyzed 318 265 214 226
Mean (Standard Deviation)
Unit of Measure: units on a scale
18.3  (6.0) 18.5  (5.5) 18.0  (6.3) 18.7  (5.5)
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Analyze Early, Analyze Later
Comments Linear regression was used to assess associations between post-discharge measures and treatment group comparisons with adjustment for baseline characteristics. Site was adjusted for to accommodate clustering of patients within sites. All regression analyses used robust standard errors to accommodate non-constant variances.
Type of Statistical Test Superiority
Comments [Not Specified]
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value 0.06
Confidence Interval (2-Sided) 95%
-0.71 to 0.83
Estimation Comments Mean ALFI-MMSE for Analyze Later minus mean ALFI-MMSE for Analyze Early (i.e. positive values favor Analyze Later).
Show Statistical Analysis 2 Hide Statistical Analysis 2
Statistical Analysis Overview Comparison Group Selection Active ITD, Sham ITD
Comments Linear regression was used to assess associations between post-discharge measures and treatment group comparisons with adjustment for baseline characteristics. Site was adjusted for to accommodate clustering of patients within sites. All regression analyses used robust standard errors to accommodate non-constant variances.
Type of Statistical Test Superiority
Comments [Not Specified]
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -0.66
Confidence Interval (2-Sided) 95%
-1.61 to 0.28
Estimation Comments Mean ALFI-MMSE for Active ITD minus mean ALFI-MMSE for Sham ITD (i.e. positive values favor the active device).
5.Secondary Outcome
Title Health Utilities Index III Score and Geriatric Depression Scale Score 6 Months
Hide Description The Health Utilities Index Mark 3 system was used to evaluate generic health related quality of life (HRQL). The interview-administered version of HUI3 requires completion of a maximum of 39 questions. The HUI3 consists of eight attributes of general health (vision, hearing, speech, mobility, dexterity, emotion, cognition, and pain) with five or six levels per attribute. For each respondent, health status is described as a vector that combines the levels of each attribute. This information is then converted into a utility score of HRQL on a scale from perfect health (1.0) to death (0).
Time Frame 6 months post hospital discharge
Show Outcome Measure DataHide Outcome Measure Data
Hide Analysis Population Description
ITT population, survived to hospital discharge, consented to participate in the post-discharge substudy, and with at least one post-discharge assessment.
Arm/Group Title Analyze Early Analyze Later Active ITD Sham ITD
Hide Arm/Group Description:
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: 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.
Sham ITD used by EMS providers in the pre-hospital setting.
Overall Number of Participants Analyzed 273 240 191 189
Mean (Standard Deviation)
Unit of Measure: units on a scale
0.74  (0.34) 0.73  (0.35) 0.71  (0.36) 0.75  (0.33)
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Analyze Early, Analyze Later
Comments Linear regression was used to assess associations between post-discharge measures and treatment group comparisons with adjustment for baseline characteristics. Site was adjusted for to accommodate clustering of patients within sites. All regression analyses used robust standard errors to accommodate non-constant variances.
Type of Statistical Test Superiority
Comments [Not Specified]
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value 0.00
Confidence Interval (2-Sided) 95%
-0.06 to 0.05
Estimation Comments Mean HUI for Analyze Later minus mean HUI for Analyze Early (i.e. positive values favor Analyze Later).
Show Statistical Analysis 2 Hide Statistical Analysis 2
Statistical Analysis Overview Comparison Group Selection Active ITD, Sham ITD
Comments Linear regression was used to assess associations between post-discharge measures and treatment group comparisons with adjustment for baseline characteristics. Site was adjusted for to accommodate clustering of patients within sites. All regression analyses used robust standard errors to accommodate non-constant variances.
Type of Statistical Test Superiority
Comments [Not Specified]
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -0.02
Confidence Interval (2-Sided) 95%
-0.08 to 0.05
Estimation Comments Mean HUI for Active ITD minus mean HUI for Sham ITD (i.e. positive values favor the active device).
Time Frame [Not Specified]
Adverse Event Reporting Description [Not Specified]
 
Arm/Group Title 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
Hide Arm/Group Description 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: 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. 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: 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: 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: 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. 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. 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.
All-Cause Mortality
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
Affected / at Risk (%) Affected / at Risk (%) Affected / at Risk (%) Affected / at Risk (%) Affected / at Risk (%) Affected / at Risk (%) Affected / at Risk (%) Affected / at Risk (%)
Total   --/--      --/--      --/--      --/--      --/--      --/--      --/--      --/--    
Show Serious Adverse Events Hide Serious Adverse Events
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
Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events
Total   154/2310 (6.67%)      193/2321 (8.32%)      122/2051 (5.95%)      166/2156 (7.70%)      174/2191 (7.94%)      121/1839 (6.58%)      181/1336 (13.55%)      152/1278 (11.89%)    
Hepatobiliary disorders                 
Liver lacerations * [1]  0/2310 (0.00%)  0 0/2321 (0.00%)  0 0/2051 (0.00%)  0 0/2156 (0.00%)  0 0/2191 (0.00%)  0 0/1839 (0.00%)  0 0/1336 (0.00%)  0 1/1278 (0.08%)  1
Respiratory, thoracic and mediastinal disorders                 
Airway bleeding  [2]  62/2310 (2.68%)  64 79/2321 (3.40%)  79 28/2051 (1.37%)  28 67/2156 (3.11%)  67 67/2191 (3.06%)  69 26/1839 (1.41%)  28 60/1336 (4.49%)  61 51/1278 (3.99%)  51
Pulmonary edema   98/2310 (4.24%)  99 120/2321 (5.17%)  121 98/2051 (4.78%)  98 104/2156 (4.82%)  104 118/2191 (5.39%)  118 99/1839 (5.38%)  101 134/1336 (10.03%)  135 108/1278 (8.45%)  109
Skin and subcutaneous tissue disorders                 
Defibrillator burns to chest *  0/2310 (0.00%)  0 0/2321 (0.00%)  0 1/2051 (0.05%)  1 0/2156 (0.00%)  0 0/2191 (0.00%)  0 0/1839 (0.00%)  0 0/1336 (0.00%)  0 0/1278 (0.00%)  0
Indicates events were collected by systematic assessment
*
Indicates events were collected by non-systematic assessment
[1]
Liver lacerations secondary to CPR with bleeding and hypotension.
[2]
Finding of frank blood or bloody fluids in the airway secretions, the oro- or naso-pharynx region, or the advanced airway by EMS or ED/hospital personnel.
Show Other (Not Including Serious) Adverse Events Hide Other (Not Including Serious) Adverse Events
Frequency Threshold for Reporting Other Adverse Events 5%
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
Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events Affected / at Risk (%) # Events
Total   0/2310 (0.00%)      0/2321 (0.00%)      0/2051 (0.00%)      0/2156 (0.00%)      0/2191 (0.00%)      0/1839 (0.00%)      0/1336 (0.00%)      0/1278 (0.00%)    
Certain Agreements
All Principal Investigators ARE employed by the organization sponsoring the study.
Results Point of Contact
Name/Title: Siobhan Brown, PhD-Biostatistician
Organization: University of Washington
Phone: 206-685-1302
EMail: spes@uw.edu
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Susanne May, University of Washington
ClinicalTrials.gov Identifier: NCT00394706     History of Changes
Other Study ID Numbers: 29919
HL077863
First Submitted: October 30, 2006
First Posted: November 1, 2006
Results First Submitted: March 23, 2012
Results First Posted: April 18, 2012
Last Update Posted: August 9, 2018