Central venous oxygen saturation (ScVO2) has been considered an important parameter for follow-up, prognostic estimate, and therapeutic target in the management of critically ill patients (pts).The objective this study is to assess the evolution of pts with an ScVO2 ≥ 70% in the postoperative (PO) period of cardiac surgery, and to correlate that finding with in-hospital mortality.
A classic cohort of 128 consecutive pts was selected from January 2004 to August 2004. Blood samples were collected through a central venous catheter properly positioned in the right atrium according to a previously validated method. The ScVO2 measurements were taken in the postoperative period as follows: immediately (SV0), after 6 hours (SV1), and after 24 hours (SV2). The pts were divided into 4 groups as follows: GI (60 pts), none of the 3 measurements was ≥ 70%; GII (33 pts), at least one of the 3 measurements was ≥ 70%; GIII (22 pts), 2 of the 3 measurements were ≥ 70%; and GIV (13 pts), all measurements were ≥ 70%. The chi-square test was used for statistical analysis. In-hospital mortality was defined as the occurrence of death during hospitalization.
In-hospital mortality in our sample was 8.6% and, in the groups, it was as follows: GI, 16.7%; GII, 3.0%; and GIII and GIV, 0%, as shown in the annexed table. After applying the chi-square test, the differences in mortality rate were significant (P = 0.023).
In the population studied, at least one ScVO2 ≥ 70% in the first 24 PO hours of cardiac surgery seems to have an impact on in-hospital mortality.
This study showed the importance of a ScVO2 to idendificate the patients with greather risk of death.
Pedro Miguel Nogueira, None.