PREDICTING SURVIVAL FROM IN-HOSPITAL CPR - METAANALYSIS AND VALIDATION OF A PREDICTION MODEL

Objective: To better clarify patient factors that predict survival fro m in-hospital cardiopulmonary resuscitation (CPR), using two methods: 1) meta-analysis and 2) validation of a prediction model, the pre-arre st morbidity (PAM) index. Design: Meta-analysis of previously publishe d studies by standard techniques. Retrospective chart review of valida tion sample. Setting: University-affiliated teaching hospital. Patient s/participants: Meta-analytic sample of 21 previous studies from 1965- 1989. The validation sample consisted of all patients surviving resusc itation from the authors' hospital during the period September 1986 to January 1991. A matched sample of patients who did not survive from t he same time period was used as the comparison group. Interventions: N one. Measurements and main results: The strongest negative predictors of survival, by meta-analysis, were renal failure (r = 0.088, p < 0.00 02), cancer (r = 0.08, p < 0.0002), and age more than 60 years (r = 0. 063, p < 0.006). Sepsis (r = 0.046, p < 0.02), recent cerebrovascular accident (CVA) (r = 0.038, p < 0.04), and congestive heart failure (CH F) class III/IV (r = 0.036, p < 0.05) were weaker negative predictors. Presence of acute myocardial infarction (AMI) was a significant posit ive predictor of survival (r = 0.15, p < 0.0001). The PAM score was hi ghly predictive of survival in a logistic regression model (p < 0.0003 , R2 = 9.6%). No patient who survived to discharge had a PAM score hig her than 8. Conclusion: Meta-analysis reveals that the most significan t negative predictors of survival from CPR are renal failure, cancer, and age more than 60 years, while AMI is a significant positive predic tor. The PAM index is a useful method of stratifying probability of su rvival from CPR, especially for those patients with high PAM scores, w ho have essentially no chance of survival.