Witnessed arrest, but not delayed bystander cardiopulmonary resuscitation improves prehospital cardiac arrest survivial
- R B Vukmir,
- and the Sodium Bicarbonate Study Group
- Correspondence to: Dr R B Vukmir University of Pittsburgh Medical Center-Northwest, One Spruce Street, Franklin, PA, USA;16323;
- Accepted 26 January 2004
Introduction: This study correlated the effect of witnessing a cardiac arrest and instituting bystander CPR (ByCPR), as a secondary end point in a study evaluating the effect of bicarbonate on survival.
Methods: This prospective, randomised, double blinded clinical intervention trial enrolled 874 prehospital cardiopulmonary arrest patients encountered in a prehospital urban, suburban, and rural regional emergency medical service (EMS) area. This group underwent conventional advanced cardiac life support intervention followed by empiric early administration of sodium bicarbonate (1 mEq/l), monitoring conventional resuscitation parameters. Survival was measured as presence of vital signs on emergency department (ED) arrival. Data were analysed using χ2 with Pearson correlation and odds ratio where appropriate.
Results: The overall survival rate was 13.9% (110 of 792) of prehospital cardiac arrest patients. The mean (SD) time until provision of bystander cardiopulmonary resuscitation (ByCPR) by laymen was 2.08 (2.77) minutes, and basic life support (BLS) by emergency medical technicians was 6.62 (5.73) minutes. There was improved survival noted with witnessed cardiac arrest—a 2.2-fold increase in survival, 18.9% (76 of 402) versus 8.6% (27 of 315) compared with unwitnessed arrests (p<0.001) with a decreased risk ratio of mortality of 0.4534 (95% CI, 0.0857 to 0.1891). The presence of ByCPR occurred in 32% (228 of 716) of patients, but interestingly did not correlate with survival. The survival rate was 18.2% (33 of 181) if ByCPR was performed within two minutes and 12.8% (6 of 47), if performed >two minutes (p = 0.3752).
Conclusions: Survival after prehospital cardiac arrest is more likely when witnessed, but not necessarily when ByCPR was performed by laymen.
- CPR, cardiopulmonary resuscitation
- CCU, coronary care unit
- EMS, emergency medical service
- ACLS, advanced cardiac life support
- EMT, emergency medical technician
- BLS, basic life support
Funding: the work was supported in part by Laerdal Acute Medicine Fund and the University of Pittsburgh Competitive Medical Research Fund.
Conflicts of interest: none declared.
Sodium Bicarbonate Study Group Primary investigator: Rade B Vukmir MD; Beaver: Paul Peindl MD, Charles Bowers EMT-P, Joseph Campbell EMT-P; Greensburg: John Reed MD, William Groft EMT-P; Indiana: Steve Bashor MD, James Dixon MD, BJ Pino EMT-P; McKees Rocks: Peter Stevenson MD, Anthony Sanvito EMT-P; Monessen: Frank Hertzog MD, Bill Hess EMT-P, Mark Sellew EMT-P, Mark Eglgi EMT-P; Monroeville: Dave Natale MD, Doug Nicole EMT-P; Pittsburgh: Laurence Katz MD, Michael Sullivan MD, Uwe Ebmeyer MD; Nicholas Bircher MD, Paul Paris MD, James Menegazzi PhD, Peter Safar MD; Sewickley: J Nagan MD, J Withee EMT-P.