Early use of mechanical CPR provides survival benefit in OHCA
Mechanical cardiopulmonary resuscitation (CPR) devices offer a survival benefit as compared to manual CPR only when applied early on-site in the management of out-of-hospital cardiac arrest (OHCA), according to a Singapore study.
Researchers conducted a prospective, randomized, multicentre study over 1 year with LUCAS 2 devices in 14 ambulances and manual CPR in 32 ambulances to manage OHCA. Return of spontaneous circulation (ROSC) was the primary outcome, while the secondary outcomes were survival at 24 hours, discharge from hospital and 30 days.
“[M]echanical CPR devices have a role to play for patients with OHCA, at least in ensuring consistent performance of good-quality chest compressions,” researchers said.
“Although the MECCA* study was unable to show a significant survival benefit with the LUCAS 2 device compared to manual CPR, the as-treated analysis suggested better survival outcomes if the device was applied early, rather than late or with standard manual CPR,” they added.
Of the 1,191 patients included in the analysis, 889 had manual CPR and 302 had LUCAS CPR. [Singapore Med J 2017;58:424-431]
The respective outcomes for manual and LUCAS CPR from an intention-to-treat perspective were as follows: ROSC, 29.2 and 31.1 percent (odds ratio [OR], 1.09; 95 percent CI, 0.82 to 1.45; p=0.537); 24-hour survival, 11.2 and 13.2 percent (OR, 1.20; 0.81 to 1.78; p=0.352); survival at discharge, 3.6 and 4.3 percent (OR, 1.20; 0.62 to 2.33; p=0.579); and 30-day survival, 3.0 and 4.0 percent (OR, 1.32; 0.66 to 2.64; p=0.430).
Based on as-treated analysis, the respective outcomes for manual, early LUCAS and late LUCAS CPR were as follows: ROSC, 28.0, 36.9 and 24.5 percent; 24-hour survival, 10.6, 15.5 and 8.2 percent; survival to discharge, 2.9, 5.8 and 2.0 percent; and 30-day survival, 2.4, 5.8 and 0.0 percent. After adjustment for other variables, the OR for survival with early LUCAS vs manual CPR was 1.47 (p=0.026).
“Mechanical CPR devices were introduced to specifically address the various interruptions in provision of good-quality manual CPR,” researchers said. “Operational challenges, such as ambulance crew not carrying it to the site because of the heavy weight of the device, mechanical faults, noncompliance to protocols by the crew and delays in the use of the device, may affect outcomes.”
As suggested by the as-treated analysis, mechanical CPR devices could potentially lead to better clinical outcomes if implemented early and efficiently for OHCA, according to researchers, adding that this can significantly improve outcomes and would be in line with the chain of survival for cardiac arrest. [Resuscitation 2008;79:133-8]
“Since the as-treated analysis suggests better survival outcomes with early use of the LUCAS 2 device than with standard manual CPR, future studies in this area of care would need to focus on the efficient use of the device, rather than on its uncontrolled, late or unguided application, to better determine the potential value of mechanical CPR in the management of OHCA,” researchers noted.
*Mechanical Cardiopulmonary Resuscitation Versus Standard Manual CPR in Out-of-Hospital Cardiac Arrest by Emergency Ambulance Crew