A Multicenter Randomized Trial Comparing a Mechanical CPR Algorithm Using LUCAS vs. Manual CPR in OHCA Patients - LINC
The current trial sought to investigate whether automated defibrillation and chest compressions with the LUCAS device would be superior to manual cardiopulmonary resuscitation (CPR) in patients with unexpected out-of-hospital cardiac arrest (OHCA).
LUCAS-guided CPR would be superior compared with manual CPR for survival at 4 hours in patients with OHCA.
- Unexpected adult OHCA where an attempt of resuscitation is considered appropriate
Number of enrollees: 2,589
Duration of follow-up: 6 months
- Traumatic cardiac arrest, including hanging
- Age believed to be <18 years
- Known pregnancy
- Patient’s body size not fitting the LUCAS
- Defibrillated before LUCAS arrives at scene; crew witnessed VF/VT with ROSC
- Survival at 4 hours
- Survival up to 6 months with good neurological outcome (CPC 1-2)
CPR was performed in both arms, per advanced cardiac life support (ACLS) 2005 guidelines. Patients randomized to LUCAS CPR were treated initially with manual compressions with minimized interruptions until the device was unpacked and ready to use. The defibrillator started out in manual mode. Mechanical compressions were continued initially for 3 minutes without checking heart rhythm, irrespective of any manual compressions that were given by bystanders. The sequence was not interrupted for a shock that was delivered during compressions after 90 seconds of this first 3-minute cycle, with the remaining 90 seconds of continued compressions to follow. Thus, the first shock was given on the basis only of definite cardiac arrest without knowledge of whether it was or was not “shockable.”
Subsequently, heart rhythm was determined after each 3-minute cycle by interrupting mechanical compressions briefly and never for longer than 10 seconds. If the analyzed rhythm was shockable, a new 3-minute cycle of compressions was started, incorporating as before one shock delivered after 90 seconds of ongoing compressions. If the rhythm was not shockable, a 3-minute cycle of compressions without any shock was followed by a new rhythm analysis. Heart rhythm and circulation were checked after each 3-minute cycle.
Irrespective of initial rhythm, all patients with return of spontaneous circulation (ROSC) were treated with a hypothermia protocol.
A total of 2,589 patients were randomized, 1,300 to LUCAS-guided CPR and 1,289 to manual CPR. Baseline characteristics were fairly similar between the two arms.
The primary endpoint of survival at 4 hours was similar between the LUCAS-guided CPR and manual CPR arms (23.6% vs. 23.7%, p = 1.0). Secondary outcomes including survival to intensive care unit (ICU) discharge (7.5% vs. 6.4%), survival to hospital discharge with cerebral performance category (CPC) 1-2 (8.3% vs. 7.8%), and 6-month survival with CPC 1-2 (8.5% vs. 7.6%) were all similar between the two arms.
The results of the LINC trial indicate that survival with meaningful neurological recovery following OHCA (especially for non-ventricular tachycardia [VT]/ventricular fibrillation [VF]) remains abysmally low (8% at 6 months) (a CPC score of 1 or 2 indicates good neurological outcome; 4 indicates comatose or vegetative state). Studies demonstrate that manual chest compressions during CPR result in only 20-30% of normal blood flow and are difficult to perform for a long period of time. Following small pilot studies, there has been recent interest in mechanical chest compressions with the LUCAS device. The current trial indicates that 4-hour survival is, however, similar between the LUCAS device and manual CPR.
Presented by Dr. Sten Rubertsson at the European Society of Cardiology Congress, Amsterdam, Holland, September 1, 2013.
Keywords: Heart Massage, Coma, Persistent Vegetative State, Intensive Care Units, Defibrillators, Tachycardia, Ventricular, Follow-Up Studies, Out-of-Hospital Cardiac Arrest, Advanced Cardiac Life Support, Cardiopulmonary Resuscitation, Ventricular Fibrillation
< Back to Listings