Abstract 203: Potential Dependence on Type of Bystander Basic Life Support Response and Outcomes in Out-of-Hospital Cardiac Arrests Managed Without Any Involvement of Physicians

Abstract

Objectives: The present study was conducted to test our hypothesis that relation of bystander to cardiac arrest victim may affect the BLAs response and outcomes in bystander-witnessed OHCAs. Methods: We obtained the Japanese nation-wide database for 547,218 OHCAs that occurred from Jan. 2005 to Dec. 2009, and extracted a dataset for 139,265 bystander-witnessed OHCAs without any involvement of physicians, that has all information for analysis. We first compared the BLS response of the four bystander groups (family members, friends and colleagues, passers-by and others). Then, we compared the outcomes of bystander-witnessed OHCAs having bystander CPR among the four groups. Results: The intervals between collapse and emergency call and between call and arrival at patient were shortest in OHCAs witnessed by pass-by. The telephone-CPR was most frequently attempted (45.8%, 41,442/90,426) but failed (39.4%, 16,315/41,442) in OHCAs witnessed by family. Consequently, the rate of bystander CPR was lowest (36.5%, 33,008/90,426), CPR was most frequently initiated following the telephone-CPR (76.1%, 25,127/33,008), and type of CPR was most frequently “chest-compression-only” (67.9%, 22,406/33,008) in OHCAs witnessed by family members. Multiple logistic regression analysis revealed that family as a type of bystander was an independent factor associated with lack of bystander CPR (Odds ratio=1.54 against passers-by, 2.09 against friends and colleagues, and 5.15 against others) . In all subcategories, the incidences of shockable initial rhythms and outcomes were lowest in the OHCAs witnessed by family members. Multiple logistic regression disclosed that that family member as a bystander group is one of the independent factor associated with 1-M unfavorable neurological outcomes in all subcategories of bystander-witnessed OHCAs. Conclusions: Family members do not quickly respond to OHCAs and unwilling to perform CPR on their own initiative. OHCAs witnessed by family and having bystander CPR have low incidences of shockable initial rhythm and 1-M favourable neurolofical survival. The first responder system that enable a good BLS performer to quickly reach the scene may be necessary in OHCAs witnessed by family.