Download ACD CPR - Rackcdn.com

The Devil is in the Details
R. J. Frascone, MD, FACEP
1
Medical Director EMS
Regions Hospital EMS, St. Paul, MN
Professor of Emergency Med
University of Minnesota
These trials were studying two
different things, in two very
different ways


The RESQ Trial studied the combination
of ACD/ITD CPR vs S-CPR
ROC PRIMED studied ITD CPR vs S-CPR
But,
The RESQ Trial looked at only ACD/ITD vs
S-CPR
 ROC PRIMED looked at two different
things: Early vs late defibrillation and ITD
CPR vs S-CPR and they did it with a
multifactoral approach
 Both trials were complex, but PRIMED was
extraordinarily complex

First A Review
(sorry)
Standard CPR
Cardiac Pump Theory:
Heart squeezed between
sternum and spine.
Thoracic Pump Theory:
Chest acts as bellows.
Compression causes
positive intrathoracic pressure:
 Blood leaves the heart from
higher pressure state (inside
the heart) to the lower
pressure state (systemic
circulation)
Compression Phase
7
Vacuum develops in the
chest, drawing air back
into the lungs and blood
back into the heart
(preload).
Chest Wall
Recoil Phase
↑ PRELOAD leads to
↑ CARDIAC OUTPUT
8
10
Inefficiency #1
 Filling
of the heart (preload) is dependent
upon the chest wall’s ability to recoil
during decompression phase.
 Chest wall recoil may be compromised by:
A stiff chest
 Broken ribs
 Just doing it wrong

11
Inefficiency #2
 Air
rushes in through an open airway and
wipes out the vacuum we’re relying on to
fill the heart.
 Heart stops filling as soon as vacuum is
equalized.
13
ACD CPR
Metronome
Force Gauge
Suction Cup
Handle
15
 Actively


compressing the chest,
increasing IP pressure and
thereby forcing blood out of
chest, just like s-CPR.
Same position as standard CPR
40 – 50 cm (1 ½ - 2”)
 Soft chest: 65 lbs
 Average chest: 90 lbs
 Stiff chest: 110 lbs
16

But, unlike S-CPR it actively
decompresses the chest,
decreasing IP pressure, thereby
drawing blood into the chest.
Typically 15-20 lbs
17
ACD-CPR Optimizes Chest Wall Recoil
S-CPR
18
ACD-CPR
Does it Work?
Standard vs. ACD CPR:
Human Study
Survival
Plaisance, P, Lurie, KG, et al. NEJM. 1999 Aug;341(8):569-575.
Standard or ACD CPR during ACLS only
45
40
1.5
35
1.5
1.4
1.9
25
standard CPR
20
ACD CPR
15
(n=377)
(n=373)
2.0
10
3.2*
5
2.5*
Iy
r
7d
ay
s
24
hr
Di
sc
ha
rg
e*
*
IC
U
ad
mi
ss
io
n
1h
r
0
RO
SC
survivors (%)
30
Odds ratios shown above bars
* Statistically significant difference
** Discharge without neurologic impairment
Standard vs. ACD CPR:
Human Study
Survival
Plaisance, P, Lurie, KG, et al. NEJM. 1999 Aug;341(8):569-575.
Standard or ACD CPR during BLS and ACLS
55
50
45
35
30
standard CPR
25
ACD CPR
20
(n=99)
(n=120)
15
10
5
Iy
r
Di
sc
ha
rg
e*
hr
24
ad
m
iss
io
n
N-
IC
U
1
hr
0
RO
SC
survivors (%)
40
* Discharge without neurologic impairment
ACD CPR
The Problem is:
 Air
rushes in through an open airway and
wipes out the vacuum we’re relying on to
fill the heart.
 Heart stops filling as soon as vacuum is
equalized.
The Solution

Enter the Impedence Threshold Device
(ITD)
Chest Compression
Patient Ventilation
Patient can freely exhale.
Patient can be freely
ventilated.
25
Chest Decompression
Influx of air is prevented, enhancing
the vacuum in the chest.
Spontaneous Breathing
Air will enter if patient creates
at least -10 cmH2O pressure
with respiratory effort.
26
Greater vacuum (negative pressure) in
the chest during chest wall recoil phase
27
ACD CPR w/ Sham ITD
ACD CPR w/ Facemask + ITD
ACD CPR w/ ET + ITD Ventilation
Plaisance et al. Crit Care Med 2005;33(5):990-994
28
mmHg
Improved Blood Pressure
P<0.05 for differences between
S-CPR & S-CPR + ITD,
and ACD-CPR & ACD-CPR + ITD
29
Pirrallo et al. Resuscitation 2005;(66):13-20 and Plaisance et al. Circulation 2000;(101):989-994.
Many other trials both in animals
and human that prove the
effectiveness of the ITD alone or in
combination with ACD
Putting it all
together
ACD/ITD CPR
in humans
Human Study
ACD CPR +/- Valve:
Plaisance, P, Lurie, KG, Payen, D. Circ. 2000;101:989-994
End-Tidal CO2
22
With Valve
Without Valve
20
22
n=8
16
n=11
14
n=7
n=10
End-Tidal CO2
n=10
18
End-Tidal CO2
24
n=9
20
18
16
14
12
10
8
6
4
12
0
n=10
n=11
Time (min)
n=10
10
n=10
8
n=11
n=8
n=10
6
4
0
5
10
15
5 10 15 20 25
20
25
30
Duration of CPR (minutes)
ACD CPR +/- Valve:
Human Study
Diastolic Arterial Pressure
60
Plaisance, P, Lurie, KG, Payen, D. Circ. 2000;101:989-994
n=9
Diastolic Arterial Pressure (mm Hg)
n=11
n=8
n=7
50
With Valve
Without Valve
40
n=10
n=10
n=10
60
50
40
30
15
20
Time (min)
30
20
15
70
10
n=10
n=8
10
Diastolic Arterial Pressure (mm Hg)
n=10
20
25
30
Duration of CPR (minutes)
25
ACD CPR +/- Valve:
Human Study
Coronary Perfusion Pressure
Coronary Perfusion Pressure (mmHg)
50
n=10
45
n=9
n=11
n=8
40
n=7
With Valve
35
Without Valve
Coronary Perfusion Pressure (mmHg)
Plaisance, P, Lurie, KG, Payen, D. Circ. 2000;101:989-994
60
50
40
30
20
10
10
15
20
Time (min)
30
n=10
n=10
n=10
n=10
25
n=8
20
15
10
15
20
25
30
Duration of CPR (minutes)
25
Paris Survival Study:
ACD CPR  ITD



Prehospital study
200 patients/arm (ACD vs. ACD/ITV)
ROSC:



ICU admission



38.5% - ACD
48% - ACD/ITV
28.5% - ACD
39.5 – ACD/ITV
24 Hour Survival


22% - ACD
32% - ACD/ITV
The ResQ Trial
Tom P. Aufderheide, MD; Ralph J. Frascone, MD; Marvin A. Wayne, MD; Brian
D. Mahoney, MD; Robert A. Swor, DO; Robert M. Domeier, MD; Michael L.
Olinger, MD; Richard G. Holcomb, PhD; David E. Tupper, PhD; Demetris
Yannopoulos, MD; Keith G. Lurie, MD
37


S-CPR
(Control)
ITD + ACD-CPR
(Intervention)
39
Survival to hospital discharge with favorable
neurologic function (measured with a
modified Rankin Scale [mRS] ≤ 3), is higher
in patients receiving an ITD + ACD-CPR
compared to patients receiving Standard
CPR (S-CPR).
40
Prospective, randomized, controlled clinical trial with
data analyzed on intent to treat basis
 Seven US sites (population base: 2.3 million):




46 EMS agencies
4950 EMS providers
25 IRBs
Patients assigned, based upon weekly block
randomization, to control or intervention group
 Study period: February 2005 – July 2010
 All study personnel blinded to aggregate data

41
Results
Survival to Hospital Discharge
with Favorable Neurologic Outcome
*
*53% improvement
P = 0.019
OR 1.58
CI (1.07, 2.36)
43
Age at Time of Arrest (years)
44
Survival to Hospital Discharge
with Favorable Neurologic Outcome
Survival to Hospital Discharge
with Favorable Neurologic Outcome
P=1.00 for differences
based on gender
Odds ratio for effect of
intervention based on
gender: 1.60
95% CI (1.10, 2.33)
45
Survival to Hospital Discharge
with Favorable Neurologic Outcome
Cumulative
Enrollment
2006
2007
2008
2009
Control
5
172
387
713
Intervention
6
168
395
703
11
340
782
1416
Total
Control
(N = 813)
One-Year Survival
Emotional:
Beck Depression Inventory (BDI)
Intervention
(N = 840)
P-value
48 (5.9%) 74 (8.8%) 0.030
5.2 ± 6.3
5.5 ± 5.9
0.862
1.4 ± 3.1
2.2 ± 5.7
0.358
92.9 ± 12.0
94.5 ± 4.5
0.473
(Score range: 0 – 63)
Functional:
Disability Rating Score (DRS)
(Score range: 0 – 29)
Cognitive:
Cognitive Abilities Screening
Instrument (CASI)
Score range: (0 – 100)
47


Compared to standard CPR, ITD + ACD-CPR
resulted in significantly increased survival to
hospital discharge with favorable neurological
function (53%).
One year after OOHCA, survival rates with similar
neurologic function were also significantly higher
in the intervention group (49%).
48
Aufderheide et al. A trial of an impedance
threshold device in out-of-hospital cardiac
arrest. NEJM 2011365;798-806.
49
Purpose

To determine if use of an active (versus
sham) ITD during standard CPR (no ACD
used) would improve rates of hospital
discharge with functional neurological
survival in adult (modified Rankin Scale
[mRS] score ≤3), non-traumatic, out of
hospital cardiac arrests
Description/Methods





10 sites in US and Canada
Prospective, randomized, blinded
Subjects: adults with arrest from presumed cardiac
etiology
2 x 2 multivariate study design
 Analyze Early (30 secs CPR) vs Analyze Later (3 min
CPR)
 Stiell et al. NEJM 2011
 Sham vs Active ITD
 Aufderheide et al. NEJM 2011
Impact of immediate CPR feedback utilizing QCPR device
@ three sites
 Hostler et al. BJM 2011
Results
Results



Overall results in sham vs active ITD were similar (≈6%)
November 2, 2009, NIH announced study terminated
early (at the 2/3 enrollment point) as it was not going to
be possible to detect any overall significant difference
between either of the study groups (AnE vs AnL, or sham
vs active ITD) even if study continued to 14,000 patients
(stopped because of futility)
No safety concerns with ITD
Conclusion
Compared with standard CPR, use of
the ITD did not significantly improve
functional survival from out-ofhospital cardiac arrest.
 When implemented under similar
conditions, routine use of the ITD is
not supported.

What are the Problems with
ROC?
The Devil is in the Details
Protocols
 Three
different BLS protocols
 ALS protocols per site medical director
Various ROC Study Protocols
BLS CPR Method
ITD
Study1
30:2 compression to
ventilation ratio
Sham vs
Active ITD
Continuous chest
compressions with
asynchronous
ventilations @ 10/min
1Aufderheide
57
et al. NEJM 2011
AE vs AL
Study2
30 secs vs 180 secs
of CPR before analyze
and shock
Did not
participate
2Stiell
et al. NEJM 2011
QCPR
Study3
Sites
Participating
Did not
participate
 Milwaukee, WI
 Dallas, TX
 San Diego, CA
 Portland, OR
 Birmingham,
AL
 Ottawa, CA
 Toronto, CA
Feedback ON
vs Feedback
OFF
 Pittsburgh, PA
 Thunder Bay,
ON
Did not
participate
 Vancouver, CA
Feedback ON
vs Feedback
OFF
 Seattle (King
County), WA
3Hostler
et al. BMJ 2011
Study Protocol
Respond to scene and determine pulselessness.
Perform 1 – 4 simultaneously:
1.Review enrollment criteria for AE vs AL study
a)
If eligible and in V-Fib, perform either 30 secs or 3 min of CPR prior to
analyzing and shocking if indicated.
b)
If eligible and in asystole or PEA, or not eligible, perform conventional
resuscitation
2.Review enrollment criteria for QCPR study
a)
If eligible, place QCPR device; then, based upon cluster
randomization, audible and visual feedback either will or will not be
given to rescuers.
b)
If not eligible, do not place QCPR device and perform conventional
resuscitation.
3.Review enrollment criteria for ITD study
a)
If eligible, select ITD in serialized order and place on patient.
b)
If not eligible, perform conventional resuscitation.
4.Perform other conventional activities of resuscitation (e.g. airway
management, IV/IO, administer medications, defibrillate)
ROC ITD Placement Intervals
First/BLS
Response
ALS
Response
Dispatch to first unit arrival
5.8
9.0
Arrival of rig carrying ITD to
application
4.0
4.0
Time from 911 call to dispatch of
EMS (estimated)
1.0
1.0
10.8 minutes
14.0 minutes
Time Intervals (minutes)
Estimated mean ITD
placement interval
59
Device Placement Intervals
ROC PRIMED Study
First/BLS
Response
5.8
ALS
Response
9.0
Arrival of rig carrying ITD to application
4.0
4.0
911 call to dispatch of EMS (estimated)
1.0
1.0
Estimated mean ITD placement interval
10.8 min
14.0 min
Median Time Intervals (minutes)
Dispatch to first unit arrival
ResQTrial Study
Mean Time Intervals (minutes)
911 call to EMS CPR start time
Time it took EMS to place devices once CPR begun
911 call to device placement
60
EMS Response
6.7
0.4 (24 secs)
7.1 min
Problems


Complicated Analyze Early vs Analyze Later & QCPR
protocols, multivariate design caused multiple problems:
 ITD placement was very delayed (up to 14 minutes)
 Almost 40% of cases did not have ITD placed within the
planned time interval (under 5 minutes)
 All the patients who survived in under approximately 4
minutes were not eligible for the ITD
 Essentially all cases of early use were on asystolic
patients
Treatment protocols were inconsistent
ResQTrial: Impact of Time to Device
Placement on Survival
Survival to Hospital Discharge
with Favorable Neurological Outcome (%)
Average Time of Device
Placement in ResQTrial
(7.1 min)
Time from 911 Call to Randomized CPR Method (min)
62
ROC PRIMED
All the patients who survived in
under approximately 4 minutes
were not eligible for the ITD.
The Bottom Line
Two Very Different Studies
 ResQ

Trial studied
ACD/ITD Combination
 ROC
PRIMED studied

ITD Alone
In Addition…



Early survivors were excluded from getting the
ITD (under 4 minutes)
ITD was used early on probable, non-survivors
(asystole)
ITD way to late for the device to be successful
66