1. Mechanical CPR Tom P. Aufderheide, MD, MS, FACEP, FACC, FAHA
Professor of Emergency Medicine
Medical College of Wisconsin

2. Presenter Disclosure Information
Financial Disclosure: Supported by grants from National Institutes of Health
Grants: NHLBI: ROC, Immediate, ResQTrial; NINDS: NETT; NIH Director’s Transformative Research Award
The contents of this presentation are solely the responsibility of the authors and do not necessarily represent the official views of the NIH, NHLBI, or NINDS.
Unlabeled/Unapproved Uses Disclosure: Have performed studies with ResQPOD®, ResQPUMP™ in patients with cardiac arrest
No financial interest whatsoever in Advanced Circulatory Systems, Inc., ResQPOD®, ResQPUMP®. any device or company
Volunteer: Take Heart America, President, Citizen CPR Foundation, Volunteer National AHA, Member, Institute of Medicine, co-author of IOM Report on Cardiac Arrest

3. Goals Mechanical CPR Load Distributing Band (AutoPulse)
Piston Driven CPR (LUCAS)
ACD+ITD CPR
2015 AHA Guidelines

4. Mechanical CPR

5. The Thumper Pneumatic piston, back board, and ventilation circuit
5 studies have shown slight hemodynamic benefit*
5 small studies have shown no survival benefit*
Rarely used outside of research laboratory *
McDonald JL. Ann Emerg Med 1982;11(6):292-5.
Ward KR, Menegazzi JJ, Zelenak RR, Sullivan RJ, McSwain NE. Ann Emerg Med 1993;22(4):
Krischer JP, Fine EG, Davis JH, Nagel EL. Chest 1987;92(2):
Chandra N, Weisfeldt ML, Tsitlik J, Vaghaiwalla F, Snyder LD, Hoffecker M, et al. Am J Cardiol 1981;48(6):
Chandra N, Rudikoff M, Weisfeldt ML. Lancet 1980;1(8161):175-8.
Krischer JP, Fine EG, Weisfeldt ML, Guerci AD, Nagel E, Chandra N. Crit Care Med 1989;17(12):

6. Vest CPR Halperin HR, N Engl J Med, 1993 Pneumatic System Valves ECG
Defibrillators
Vest
Halperin HR, N Engl J Med, 1993

7. The AutoPulse™
Automated, portable, battery-powered load distributing band
Capitalizes on hemodynamic benefits of circumferential vest CPR
Distributed compression allows for large increases in intrathoracic pressure without the trauma
Hemodynamic effect: increased intrathoracic pressure on the downstroke of CPR

8. AutoPulse Traps Air on Downstroke Increasing Intrathoracic Pressure
Release
Peak Compression
Airway Open
Airway Collapsed

9. Lund University cardiac arrest System (LUCAS™)
Compressed gas or battery-powered piston technique
Modified with addition of a suction cup
Active decompression to neutral, uncompressed position
Hemodynamic effect: complete chest recoil and increased venous return on upstroke of CPR

10. Variable Quality of CPR
Wide variations in practice even in the best EMS systems (ROC)
Variable compression depth and rate limit blood flow and worsens outcomes
Compression Depth
Compression Rate
Idris 2012
Stiell 2012
Probability of Survival to Hospital Discharge
Probability of Survival to Hospital Discharge
Depth (mm)
Average Rate Per Minute
Variations in CPR quality strongly linked to outcomes 10

11. Quality of CPR Delivered is Better with Mechanical CPR*
Parameter
Mechanical CPR
Manual CPR
P Value
Correct compressions
99%
59%
P<0.001
Depth
79%
Pressure point
100%
Complete release
97%
“Hands off” time
46 seconds
106 seconds
*Putzer G, et al. Am J Emerg Med 2013 Feb;31(2): (LUCAS Device)

12. Hemodynamics Improved with AutoPulse CPR*
*Halperin H et al. J Am Coll Cardiol. 2004;44(11): (AutoPulse)

13. Hemodynamics with AutoPulse CPR
Mechanical CPR
Significantly improved coronary perfusion pressure (p<0.0001)
Significantly improved myocardial and cerebral blood flow (p<0.05)
Obtained pre-arrest levels of myocardial and cerebral blood flow

14. Hemodynamics Significantly Improved with LUCAS CPR*
Parameter
LUCAS CPR
Manual CPR
P Value
Aortic Pressure (mmHg)
42±1
33±1
P>0.001
R Atrial Pressure (mmHg)
38±4
23±2
P<0.01
Coronary Perfusion Pressure
17±1
10±1
P<0.05
Cardiac Output (l/min)
58±4
32±5
ETCO2 (%)
2.8±0.1
2.0±0.2
Carotid Blood Flow (ml/min)
*Steen S, et al. Resuscitation 2002, 55 (3): 285–99.

15. Outcome

16. Largest Mechanical CPR Meta-Analysis*
Human subjects
12 studies with 6,538 patients
Odds Ratio of Piston Driven-CPR (PD-CPR) and Load Distributing Band-CPR (LDB-CPR) vs manual-CPR (M-CPR) for ROSC
Controlled (randomized, historical, or case- control) 
Out-of-hospital
*Westfall M et al. Crit Care Med Jul;41(7):

17. Piston Driven-CPR (PD-CPR) vs Manual CPR (4 studies)
*Westfall M et al. Crit Care Med Jul;41(7):

18. Distributing Band-CPR (LDB-CPR) vs Manual-CPR
*Westfall M et al. Crit Care Med Jul;41(7):

19. Before/After Study Richmond, Virginia*
Compared LDB-CPR to manual CPR after EMS system switched
499 patients = manual CPR; 210 patients = LDB- CPR
LDB-CPR vs. Manual CPR
ROSC: 34.5% vs 20.2%, p<0.05
Survival to hospital D/C: 9.7% vs 2.9%, p<0.05
Conclusion: LDB-CPR associated with significantly improved survival
Weakness: historical control
Strength: all cardiac arrests included
*Ong ME, et al. JAMA 2006;295(22):

20. Prospective, Randomized Controlled Trials – AutoPulse
ASPIRE
Block randomization
AutoPulse vs. manual CPR
Primary endpoint: survival to 4 hours
Secondary endpoint: survival to HD
DSMB terminated study
1° endpoint:(N = 1071; 30% vs 29%; P = .74)
2° endpoint (5.8% vs. 9.9%, p=0.06)
Interpretation problematic: most LDB-CPR deaths in 1 site after CPR protocol changed

21. Prospective, Randomized Controlled Trials – AutoPulse
CIRC Trial
Randomized, unblinded, controlled group sequential trial
Quality of CPR and study design high quality
AutoPulse (N=2099) vs. manual CPR (N=2132)
1° endpoint: survival to hospital discharge
Outcome (AutoPulse vs. Manual CPR)
ROSC: 28.6% vs. 32.3%
24-hour survival: 21.8% vs. 25.0%
Survival to hospital. discharge: 9.4% vs. 11.0%
Adjusted odds ratio: 1.06 (95% CI ), meeting criteria for equivalence
Conclusion: Compared to manual CPR, AutoPulse resulted in statistically equivalent survival to hospital discharge.

22. Prospective, Randomized Controlled Trials – LUCAS
LINC Trial
Purpose: mechanical CPR with defibrillation during ongoing compressions (n = 1300) vs. manual CPR (n = 1289)
1° endpoint: 4-hour survival
2° endpoint: 6-month survival with CPC 1 or 2
Outcome (LUCAS vs. manual)
4-hour survival: 23.6% vs. 23.7%, p = .99
6-month survival with CPC 1 or 2: 8.5% vs 7.6% (risk difference, 0.86%; 95% CI, -1.2% to 3.0%)
Conclusions
No significant difference in 4-hour survival
Vast majority of survivors in both groups had good neurological outcomes by 6 months
Mechanical CPR did not result in improved effectiveness

23. Chest Compression Pause for Shock: Decreased Survival with Pause >10 Seconds
*Cheskes S, et al. Circulation 2011;124:58-66

24. Importance of Pre-shock and Peri-Shock Pause*
Survival: pre-shock pause <10s (OR: 1.52, 95% CI: 1.09, 2.11)
Survival: peri-shock pause <20s (OR: 1.82, 95% CI: 1.17, 2.85)
Shock can be delivered with NO pre- or peri- shock pause with mechanical CPR!
Potential to increase VF survival 50-80% with mechanical CPR

25. Patient transport in EMS
Mechanical CPR is the only way to provide high- quality CPR during transport and in closed spaces*
Safety*
Ambulance personnel must provide CPR without being restrained by seatbelts or other protection
Ambulance personnel are at least 4 times more likely to have a fatal or incapacitating injury
*Putzer G, et al. Am J Emerg Med 2013 Feb;31(2):384-9.
*Becker L, et al. Accid Anal Prev 2003;35(6):941-8.
*Slattery DE, et al. Prehosp Emerg Care 2009;13(3):

26. Patient transport in EMS
Can provide life-sustaining circulation in carefully selected patients refractory to successful resuscitation transported to the catheterization laboratory to reopen blocked arteries*
Mechanical CPR used for cardiac arrest in the cath lab*
*Dumas F, Cariou A, Manzo-Silberman S, et al. Immediate percutaneous coronary intervention is associated with better survival after out-of-hospital cardiac arrest: insights from the PROCAT (Parisian Region Out of hospital Cardiac ArresT) registry. Circ Cardiovasc Interv. 2010;3(3):
*Garot P, Lefevre T, Eltchaninoff H, et al. Six-month outcome of emergency percutaneous coronary intervention in resuscitated patients after cardiac arrest complicating ST-elevation myocardial infarction. Circulation. 2007;115(11):  
*Larsen AI, Hjornevik A, Bonarjee V, Barvik S, Melberg T, Nilsen DW. Coronary blood flow and perfusion pressure during coronary angiography in patients with ongoing mechanical chest compression: a report of 6 cases. Resuscitation. 2010;81(4):
*Grogaard HK, Wik L, Eriksen M, Brekke M, Sunde K. Continuous mechanical chest compressions during cardiac arrest to facilitate restoration of coronary circulation with percutaneous coronary intervention. J Am Coll Cardiol. 2007;50(11):
*Bonnemeier C, Olivecrona G, Simonis G, et al. Automated continuous chest compression for in-hospital cardiopulmonary resuscitation of patients with pulseless electrical activity: a report of five cases. Int J Cardiol. 2009;136(2):E39-E50.

27. Practical Benefits
Allows rescuers to focus on performing other interventions
Standardizes the quality of chest compressions
No fatigue
High quality CPR in a limited space
Cost Effectiveness
Reduced personnel
Saves resources
Reduced injury

28. The ResQTrial

29. ACD-CPR + ITD (Intervention)29 29
CPR Methods Compared
S-CPR (Control)
ACD-CPR + ITD (Intervention)

30. Survival to Hospital Discharge with Favorable Neurologic Outcome (%)30 30
Results: Primary Endpoint *
Survival to Hospital Discharge with Favorable Neurologic Outcome (%)
*52% improvement
P = 0.019
OR 1.58
CI (1.07, 2.36)

31. One-Year Survival 48 (5.9%) 74 (8.8%) 0.030
Results: One-year Survival
Control
(N = 813)
Intervention
(N = 840)
P-value
One-Year Survival
48 (5.9%)
74 (8.8%)
0.030
Emotional:
Beck Depression Inventory (BDI)
(Score range: 0 – 63)
5.2 ± 6.3
5.5 ± 5.9
0.862
Functional:
Disability Rating Score (DRS)
(Score range: 0 – 29)
1.4 ± 3.1
2.2 ± 5.7
0.358
Cognitive:
Cognitive Abilities Screening Instrument (CASI)
Score range: (0 – 100)
92.9 ± 12.0
94.5 ± 4.5
0.473

32. Conclusions
There were no differences in any clinically significant safety endpoints.
Compared with S-CPR, ACD-CPR + ITD resulted in a 52% improvement in survival to hospital discharge with favorable neurologic function.
This benefit was sustained to 1 year (49% higher 1-year survival with favorable neurological function)
Aside from very early defibrillation, there has never been a cardiac arrest intervention that significantly improves survival with favorable neurological function

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FDA Approval
The Food and Drug Administration approved ResQCPR (ACD + ITD CPR) for general use in the United States on March 6, 2015

34. 2015 AHA Recommendations: Piston Devices
The evidence does not demonstrate a benefit with the use of mechanical piston devices for chest compressions versus manual chest compressions in patients with cardiac arrest. Manual chest compressions remain the standard of care for the treatment of cardiac arrest, but mechanical piston devices may be a reasonable alternative for use by properly trained personnel. (Class IIb, LOE B-R)
The use of mechanical piston devices may be considered in specific settings where the delivery of high-quality manual compressions may be challenging or dangerous for the provider (eg, limited rescuers available, prolonged CPR, during hypothermic cardiac arrest, in a moving ambulance, in the angiography suite, during preparation for extracorporeal CPR [ECPR]), provided that rescuers strictly limit interruptions in CPR during deployment and removal of the devices. (Class IIb, LOE C-EO)

35. 2015 AHA Recommendations: Load Distributing Band
The evidence does not demonstrate a benefit with the use of LDB- CPR for chest compressions versus manual chest compressions in patients with cardiac arrest. Manual chest compressions remain the standard of care for the treatment of cardiac arrest, but LDB-CPR may be a reasonable alternative for use by properly trained personnel. (Class IIb, LOE B-R)
The use of LDB-CPR may be considered in specific settings where the delivery of high-quality manual compressions may be challenging or dangerous for the provider (eg, limited rescuers available, prolonged CPR, during hypothermic cardiac arrest, in a moving ambulance, in the angiography suite, during preparation for ECPR), provided that rescuers strictly limit interruptions in CPR during deployment and removal of the devices. (Class IIb, LOE C- EO)

36. 2015 AHA Recommendations: ACD + ITD CPR
The combination may be a reasonable alternative in settings with available equipment and properly trained personnel. (Class IIb, LOE C-LD)

37. Summary Compared to manual CPR, mechanical CPR provides:
Significantly better quality of CPR
Significantly better hemodynamics
Significantly improved chance of ROSC
No pre- or peri-shock pause
High quality CPR during transport
Safety for EMS personnel during transport
Opportunity to transport selected patients to the cath lab

38. Summary Compared to manual CPR, mechanical CPR provides:
Effective CPR for cardiac arrest in the cath lab
Allows rescuers to perform other interventions
Standardizes the quality of chest compressions
No fatigue or reduced quality of CPR with time
High quality CPR in a limited space
Expense versus safety and potentially reduced personnel
No RCT has yet shown mechanical CPR improves outcome from cardiac arrest compared with manual CPR

39. Mechanical CPR Conclusions
Mechanical CPR is safe and appears to provide similar or equivalent effectiveness to manual CPR
Decision to use or not use mechanical CPR based on practical considerations, understanding it does not improve outcome from cardiac arrest

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Thank You!!