Objectives: To determine factors associated with cardiopulmonary resuscitation (CPR) provision by CPR-trained bystanders and to determine factors associated with CPR performance by trained bystanders.
Methods: The authors performed a prospective, observational study (January 1997 to May 2003) of individuals who called 911 (bystanders) at the time of an out-of-hospital cardiac arrest. A structured telephone interview of adult cardiac-arrest bystanders was performed beginning two weeks after the incident. Elements gathered during interviews included bystander and patient demographics, identifying whether the bystander was CPR trained, when and by whom the CPR was performed, and describing the circumstances of the event. If CPR was not performed, we asked the bystanders why CPR was not performed. Logistic regression was used to calculate odds ratios and 95% confidence intervals (95% CI) for factors associated with CPR performance.
Results: Of 868 cardiac arrests, 684 (78.1%) bystander interviews were completed. Of all bystanders interviewed, 69.6% were family members of the victims, 36.8% of the bystanders had more than a high-school education, and 54.1% had been taught CPR at some time. In 21.2% of patients, the bystander immediately started CPR, and in 33.6% of cases, someone started CPR before the arrival of emergency medical services (EMS). Important overall predictors of CPR performance were the following: witnessed arrest (OR = 2.3; 95% CI = 1.4 to 3.8); bystander was CPR trained (OR = 6.6; 95% CI = 3.5 to 12.5); bystander had more than a high-school education (OR = 2.0; 95% CI = 1.2 to 3.1), or arrest occurred in a public location (OR = 3.1; 95% CI = 1.7 to 5.8). These variables were significant predictors of CPR performance among CPR-trained bystanders, as was CPR training within five years (OR = 4.5; 95% CI = 2.8 to 7.3). Common reasons that the CPR-trained bystanders cited for not performing CPR were the following: 37.5% stated that they panicked, 9.1% perceived that they would not be able to do CPR correctly, and 1.1% thought that they would hurt the patient. Surprisingly, only 1.1% objected to performing mouth-to-mouth resuscitation.
Conclusions: A minority of CPR-trained bystanders performed CPR. CPR provision was more common in CPR-trained bystanders with more than a high-school education and when CPR training had been within five years. Previously espoused reasons for not doing CPR (mouth-to-mouth, infectious-disease risk) were not the reasons that bystanders cited for not doing CPR. Further work is needed to maximize CPR provision after CPR training.