Introduction:

Monitoring during anesthesia is mandatory.

Objective:

To determine the central venous oxygen saturation during anesthesia.

Material and methods:

A prospective study of 25 patients with severe preeclampsia undergoing cesarean section under spinal anesthesia. Central venous oxygen saturation and mean arterial pressure were determined: basal, at minute 12 of the administration of the spinal dose, and at the end of anesthesia. Student’s t-test, Spearman’s correlation coefficient, p < 0.05 significant.

Results:

Baseline central venous oxygen saturation, 77.6 ± 7.0%; at minute 12, 77.9 ± 5.3%; and at the end of anesthesia, 76.1 ± 7.2%. Central venous oxygen saturation < 70% occurred in 8% cases (baseline) and 20% (final). The baseline of mean arterial pressure was 114.1 ± 13.9 mmHg; at minute 12, 95.5 ± 15.4 mmHg and at the end of anesthesia 96.1 ± 11.1 mmHg (p < 0.05). There was no correlation between mean arterial blood pressure and central venous oxygen saturation. There was a significant association between hemoglobin and central oxygen saturation.

Conclusion:

The central venous oxygen saturation during spinal anesthesia did not present significant differences. The identification of severe preeclamptic patients with central venous oxygen saturation < 70% should alert clinicians about the compromise of maternal tissue oxygenation. The non-correlation between central venous oxygen saturation and mean arterial blood pressure suggests the two parameters should be measured and interpreted independently.