Question 14

The images (Image A and Image B) below depict a mechanical / automated chest compression device.

automated chest compression devices

With respect to the use of these devices in cardiopulmonary resuscitation:

a) What are the potential advantages of these devices over standard practice? (40% marks)

b)  What are the potential disadvantages associated with their use? (30% marks)

c)  Summarise the role of these devices in clinical practice. (30% marks)

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College Answer


  • Consistent quality CPR
  • Decreases number of personnel required to run the arrest (remote locations)
  • Reduced interruptions to chest compressions
  • Defibrillation can be administered during compressions
  • Improves ability to perform procedures such as ECMO insertion, percutaneous coronary intervention.
  • Improves ability to transport patient to definitive care while performing effective CPR.


  • Increased “hands-off” time due to delay in application of the device
  • Visceral injuries- lung, liver, spleen, gastric
  • Rib and sternal fractures
  • Bleeding-mediastinal, epicardial, pericardial, aortic (rate of injuries with mechanical CPR are probably higher than those seen with manual CPR)


  • Randomised controlled trials (CIRC , LINC, ParaMeDiC) have shown no improvement in outcome when
comparing these devices to manual compressions
  • May have a role in transporting patients, during procedures or in settings where there are limited personnel
  • May contribute to good outcomes when used as part of an aggressive interventional bundle, including early 
reperfusion and ECMO in well-resourced settings (CHEER trial)


The following answer pertains mainly to the Zoll Autopulse  and the LUCAS Device.

Advantages of mechanical CPR:

  • CPR is of uniform (presumably, high) quality.
  • CPR is not interrupted for defibrillation.
  • Angiography or ECMO cannulation may take place with CPR in progress.
  • The device is more portable than a group of rescuers.

Disadvantages of mechanical CPR:

  • The device takes time to set up. This is time "off the chest".
  • An incorrectly aligned device might actually perform poorer compressions than a rescuer, because a rescuer corrects their own position.
  • There may be more injuries: in the CIRC trial for example the rate of rib fractures was almost doubled (from 31 to 69 of ~ 2100 patients), and the risk of pneumothrax increased by a third (those guys were using the Zoll)
  • Other theoretical injury patterns include liver, lung,  spleen and stomach lacerations, as well as mediastinal or aortic trauma. It is assumed that this will not be seen with normal human CPR because the humans perform weaker CPR on average , i.e. the machine is too effective.

Evidence to support or refute these statements:

  • Smekal et al (2011).
  • CIRC (Wik et al, 2014)
  • LINC (Rubertsson et al, 2014)
  • PARAMEDIC (Perkins et al, 2015)
  • CHEER (Stub et al, 2015)
  • Gates et al (2015) - a meta-analysis of all of the above: did not find any benefit in in-hospital mortality, rates of ROSC or neurological recovery. Moreover there did not seem to be any difference between the two devices.

Role of mechanical CPR devices in clinical practice:

  • Use where CPR will be prolonged, and consistent quality will be required
    • Cardiac arrest due to hypothermia
    • Cardiac arrest following thrombolysis for PE or MI
  • Use where rescuers are few, or unskilled:
    • Pre-hospital setting
    • Rural and regional setting
  • Use where space is limited
    • Aeromedical retrieval
    • Ambulance transport
    • Interventional radiology suite
  • Use as a part of a larger ECPR bundle a'la CHEER


Stub, Dion, et al. "Refractory cardiac arrest treated with mechanical CPR, hypothermia, ECMO and early reperfusion (the CHEER trial)." Resuscitation 86 (2015): 88-94.

Rubertsson, Sten, et al. "Mechanical chest compressions and simultaneous defibrillation vs conventional cardiopulmonary resuscitation in out-of-hospital cardiac arrest: the LINC randomized trial." Jama 311.1 (2014): 53-61.

Perkins, Gavin D., et al. "Mechanical versus manual chest compression for out-of-hospital cardiac arrest (PARAMEDIC): a pragmatic, cluster randomised controlled trial." The Lancet 385.9972 (2015): 947-955.

Wik, Lars, et al. "Manual vs. integrated automatic load-distributing band CPR with equal survival after out of hospital cardiac arrest. The randomized CIRC trial." Resuscitation 85.6 (2014): 741-748.

Steen, Stig, et al. "The critical importance of minimal delay between chest compressions and subsequent defibrillation: a haemodynamic explanation." Resuscitation 58.3 (2003): 249-258.

Gallagher, E. John, Gary Lombardi, and Paul Gennis. "Effectiveness of bystander cardiopulmonary resuscitation and survival following out-of-hospital cardiac arrest." Jama 274.24 (1995): 1922-1925.

Yu, Ting, et al. "Adverse outcomes of interrupted precordial compression during automated defibrillation." Circulation 106.3 (2002): 368-372.

Ochoa, F. Javier, et al. "The effect of rescuer fatigue on the quality of chest compressions." Resuscitation 37.3 (1998): 149-152.

Hallstrom, Al, et al. "Manual chest compression vs use of an automated chest compression device during resuscitation following out-of-hospital cardiac arrest: a randomized trial." Jama 295.22 (2006): 2620-2628.

Pantazopoulos, C., et al. "1036. Comparison of the hemodynamic parameters of two external chest compression devices (LUCAS versus AUROPULSE) in a swine model of ventricular fibrillation." Intensive Care Medicine Experimental 2.Suppl 1 (2014): P83.

Gates, Simon, et al. "Mechanical chest compression for out of hospital cardiac arrest: Systematic review and meta-analysis." Resuscitation 94 (2015): 91-97.


Smekal, David, et al. "A pilot study of mechanical chest compressions with the LUCAS™ device in cardiopulmonary resuscitation." Resuscitation 82.6 (2011): 702-706.