Quality of CPR: An important effect modifier in cardiac arrest clinical outcomes and intervention effectiveness trials.

Pubmed ID: 26073276

Journal: Resuscitation

Publication Date: Sept. 1, 2015

MeSH Terms: Humans, Clinical Trials as Topic, Cardiopulmonary Resuscitation, Emergency Medical Services, North America, Out-of-Hospital Cardiac Arrest

Grants: R01 HL126092

Authors: Yannopoulos D, Aufderheide TP, Abella BS, Duval S, Frascone RJ, Goodloe JM, Mahoney BD, Nadkarni VM, Halperin HR, O'Connor R, Idris AH, Becker LB, Pepe PE

Cite As: Yannopoulos D, Aufderheide TP, Abella BS, Duval S, Frascone RJ, Goodloe JM, Mahoney BD, Nadkarni VM, Halperin HR, O'Connor R, Idris AH, Becker LB, Pepe PE. Quality of CPR: An important effect modifier in cardiac arrest clinical outcomes and intervention effectiveness trials. Resuscitation 2015 Sep;94:106-13. Epub 2015 Jun 12.

Studies:

Resuscitation Outcomes Consortium (ROC) Prehospital Resuscitation Using an Impedance Valve and Early Versus Delayed Analysis (PRIMED)

Abstract

OBJECTIVES: To determine if the quality of CPR had a significant interaction with the primary study intervention in the NIH PRIMED trial. DESIGN: The public access database from the NIH PRIMED trial was accessed to determine if there was an interaction between quality of CPR performance, intervention, and outcome (survival to hospital discharge with modified Rankin Score (mRS) ≤ 3). SETTING: Multi-centered prehospital care systems across North America. PATIENTS: Of 8719 adult patients enrolled, CPR quality was electronically recorded for compression rate, depth, and fraction in 6199 (71.1%), 3750 (43.0%) and 6204 (71.2%) subjects, respectively. "Acceptable" quality CPR was defined prospectively as simultaneous provision of a compression rate of 100/min (± 20%), depth of 5 cm (± 20%) and fraction of > 50%. Significant interaction was considered as p < 0.05. INTERVENTION: Standard CPR with an activated versus sham (inactivated) ITD. MEASUREMENTS AND MAIN RESULTS: Overall, 848 and 827 patients, respectively, in the active and sham-ITD groups had "acceptable" CPR quality performed (n = 1675). There was a significant interaction between the active and sham-ITD and compression rate, depth and fraction as well as their combinations. The strongest interaction was seen with all three parameters combined (unadjusted and adjusted interaction p-value, < 0.001). For all presenting rhythms, when "acceptable" quality of CPR was performed, use of an active-ITD increased survival to hospital discharge with mRS ≤ 3 compared to sham (61/848 [7.2%] versus 34/827 [4.1%], respectively; p = 0.006). The opposite was true for patients that did not receive "acceptable" quality of CPR. In those patients, use of an active - ITD led to significantly worse survival to hospital discharge with mRS ≤ 3 compared to sham (34/1012 [3.4%] versus 62/1061 [5.8%], p = 0.007). CONCLUSIONS: There was a statistically significant interaction between the quality of CPR provided, intervention, and survival to hospital discharge with mRS ≤ 3 in the NIH PRIMED trial. Quality of CPR delivered can be an underestimated effect modifier in CPR clinical trials.