From the Guidelines
The automated compression machine that paramedics use during a cardiac arrest (code) is called a mechanical CPR device, with one of the most common brands being the LUCAS (Lund University Cardiac Arrest System) device. These devices deliver consistent, high-quality chest compressions at the appropriate depth and rate without the fatigue that affects human rescuers. The LUCAS uses a piston mechanism with a suction cup that attaches to the patient's chest [ 1 ]. According to the 2015 American Heart Association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care, manual chest compressions remain the standard of care for the treatment of cardiac arrest, but mechanical piston devices like LUCAS may be considered in specific settings where the delivery of high-quality manual compressions may be challenging or dangerous for the provider [ 1 ].
Some of the key benefits of mechanical CPR devices include:
- Freeing up paramedics to perform other critical interventions during resuscitation
- Ensuring compression quality doesn't deteriorate over time
- Allowing for continuous compressions during patient transport when manual CPR would be difficult or dangerous
- Maintaining the crucial blood flow to vital organs during cardiac arrest, potentially improving the chances of successful resuscitation
It's worth noting that while mechanical CPR devices have potential benefits, the evidence does not demonstrate a significant benefit with the use of mechanical piston devices for chest compressions versus manual chest compressions in patients with cardiac arrest [ 1 ]. However, in real-life clinical practice, the decision to use a mechanical CPR device should be made on a case-by-case basis, taking into account the specific circumstances and the potential benefits and limitations of these devices.
From the Research
Automated Compression Machines
- The automated compression machines used by paramedics in a code are called mechanical chest compression devices, with examples including the AutoPulse and the LUCAS 2, 3, 4, 5.
- These devices are designed to provide high-quality chest compressions during cardiopulmonary resuscitation (CPR) and can be used in situations where manual compressions are not possible or effective 6, 4.
- The AutoPulse and LUCAS devices have different mechanisms of action, with the AutoPulse working by increasing intrathoracic pressures and the LUCAS device working by compression of the sternum 2.
- The choice of device may depend on the patient's chest configuration, with the AutoPulse potentially being more effective in patients with increased anterior-posterior chest diameter and decreased chest compliance, and the LUCAS device being more effective in patients with narrower anterior-posterior diameters and a more compliant chest 2.
Effectiveness of Mechanical Chest Compression Devices
- Studies have shown that mechanical chest compression devices are not associated with improved rates of return of spontaneous circulation (ROSC) or survival with good neurologic function compared to manual chest compressions 3, 4.
- However, mechanical compression devices may be beneficial in select circumstances, such as when there are few rescuers available, during prolonged arrest or transport, or in situations where consistent, high-quality manual chest compressions are not possible 6, 4, 5.
- The use of mechanical chest compression devices can allow for continued percutaneous coronary intervention (PCI) or pericardiocentesis despite ongoing cardiac or circulatory arrest with artificially sustained circulation 5.