Clinical and Experimental Circulation
Background and Goal of Study: To evaluate SvO2 as a predictor of the outcome of patients with postcardiotomy low cardiac output syndrome.
Materials and Methods: 71 patients with low cardiac output syndrome who underwent cardiac surgery under CPB, on maximal inotropic support and IABP, were analyzed in a retrospective study. The values of SvO2 at 2 hours after the arrival in ICU were introduced into a correlation and regression tree model by univariate analysis.
Results and Discussions: It was found a cutoff point value of SvO2 of 60.3% between survivors and non-survivors. Among the 39 patients with SvO2 > 60.3% the mortality was 10.25% (4 patients) and among the 32 patients with SvO2 < 60.3% the mortality was 96.87% (31 patients) (p < 0.01). Another cutoff point permit the separation of non-survivors in two subgroups: patients weaned and non-weaned of ventricular mechanical assistance. The first subgroup were the patients with SvO2 > 51.4% but lower than 60.3% who were weaned of IABP but died later due to MSOF. Among those 16 patients were weaned 62.5% (10 patients). The second subgroup were the patients with SvO2 < 51.4% who most of them died early due to acute heart failure. The weaning rate among those 16 patients was 25% (4 patients).
Conclusion(s): We can conclude that SvO2 can predict early after implantation the success or failure of IABP support in terms of survival or not (SvO2 > 60% predict survival >90%). Patients with SvO2 < 60% will die by MSOF even if they will be wean of IABP. In these cases we should think to another method to improve cardiac function and prevent MSOF (LVAD, transplantation, etc.).