[Variations on in-hospital mortality rates based on an administrative database aortocoronary bypass mortality rate]

The aim of this work is to assess outcomes of coronary artery bypass graft in Spain, studying in-hospital mortality rates, comparing results across hospitals where this procedure is performed, investigating the variables associated with mortality, and trying to determine whether the differences in each hospital could be explained by differences in quality or by differences in the selection of patients.

Observational study. Patients were registered in the UHDMDS from year 1994 with the codes of ICD 9 CM: 36.10 a 36.19. Crude mortality rates by hospital will be obtained, as well as mortality odds ratios for different variables, and standardized mortality ratio, obtaining the expected mortality for each hospital based on the age, sex, Charlson comorbidity index, and priority of the admission of the patients.

The overall mortality rate was 4.8%. Mortality was higher in some age groups (65-69, 70-74 and > 79 years), when Charlson comorbidity index was equal or higher than 2, and in cases of urgent admission. Differences between observed and standardized mortality rate in the five hospitals with more than 150 interventions were not statistically significant.