The Lund University Cardiopulmonary Assist System 2, or LUCAS 2, is a mechanical device used to perform chest compressions on an adult patient experiencing cardiac arrest. Its development was prompted by the challenges paramedics face in delivering effective manual cardiopulmonary resuscitation (CPR), especially in difficult environments. The system delivers consistent, high-quality compressions automatically to help circulate blood. This automation provides a portable solution for first responders and hospital staff.
How the LUCAS 2 Device Functions
The LUCAS 2 device operates using mechanical and electronic components designed for stability. Its core structure includes a rigid backplate placed under the patient, providing a firm surface that prevents the “mattress effect” where compression force is absorbed by a soft surface. Two support legs attach to the backplate and arch over the patient’s chest, creating a stable platform for the compression mechanism, which houses a battery-operated piston with a suction cup.
To deploy the device, rescuers slide the backplate under the patient with minimal interruption to manual CPR. The upper part is then locked onto the backplate, and the suction cup is positioned over the center of the patient’s chest. Once activated, the piston delivers compressions and decompressions at a consistent rate and depth, adhering to CPR guidelines. The LUCAS 2 is programmed to deliver compressions at a rate of 102 per minute, and the suction cup allows for active decompression, helping the chest recoil to its normal position.
Scenarios for Deployment
The LUCAS 2 is used in various medical settings, both pre-hospital and in-hospital. In pre-hospital environments, paramedics and EMTs deploy the device in ambulances. Performing effective manual CPR in a moving vehicle is physically challenging and can be unsafe. The LUCAS 2 allows rescuers to be properly belted and seated while the patient receives uninterrupted, high-quality compressions during transport.
Within the hospital, the device is used in emergency departments, intensive care units, and cardiac catheterization labs. During prolonged resuscitation attempts, the LUCAS 2 can take over the physically demanding task of chest compressions to prevent rescuer fatigue. It is also valuable during complex procedures, such as percutaneous coronary intervention (PCI), where it provides circulatory support without interfering with medical imaging. Its use is a practical alternative when maintaining manual compressions is difficult due to personnel shortages or patient positioning.
Mechanical Versus Manual Chest Compressions
A primary advantage of the LUCAS 2 is its ability to deliver chest compressions with unwavering consistency, which is difficult to maintain with manual CPR. Human rescuers experience fatigue over time, leading to a decline in the rate and depth of compressions. The LUCAS 2 eliminates this human variable by providing automated compressions that adhere to programmed guidelines. This ensures every compression is delivered with the same force and frequency, which can lead to better coronary perfusion pressure.
A mechanical device also frees up the resuscitation team to focus on other tasks. While the LUCAS 2 manages chest compressions, providers can dedicate their attention to airway management, establishing intravenous access, administering medications, and diagnosing the cause of the cardiac arrest. This multitasking capability can streamline the resuscitation effort and improve the team’s overall efficiency.
Despite these benefits, transitioning from manual CPR to the LUCAS 2 requires a brief pause in compressions to position the device correctly. Teams must be well-trained to deploy the device efficiently to minimize this “hands-off” time. While some studies show mechanical CPR does not significantly improve the return of spontaneous circulation (ROSC) compared to high-quality manual CPR, its ability to sustain compressions during transport and complex procedures remains a distinct operational advantage.
Evolution to the LUCAS 3
The LUCAS 2 has been succeeded by the LUCAS 3, a newer model built on the same principles but with technological advancements. The LUCAS 3 introduces upgrades to improve performance and data integration. One significant enhancement is the battery technology; the LUCAS 3 battery charges in less than two hours while inside the device, compared to the four hours required by the LUCAS 2’s external charger.
Another difference is the inclusion of wireless connectivity in the LUCAS 3. This model is equipped with Bluetooth, allowing it to connect to the LIFENET System and transmit post-event data wirelessly. This feature enables easier data collection for quality improvement reviews and post-event analysis.
Design modifications were also made to enhance usability, with subtle refinements aimed at making deployment faster for rescue teams. Both the LUCAS 2 and LUCAS 3 batteries are interchangeable, with the only difference being their color for easy identification. These improvements reflect a continuous effort to refine the technology for better clinical efficiency.