Is the Perfusion Index Useful in Early Detection of High Spinal Subarachnoid Block during Cesarean Section?

To investigate the usefulness of the perfusion index (PI) in the early detection of high spinal subarachnoid block (SAB) for cesarean section (CS).

SAB was applied in patients of CS. The patients was subdivided into two groups, according to the highest level of block: the Ce group (cervical spine level) and the Th group (thoracic spine level). The PI values in the finger and toe, and vital signs were measured at pre- and post-SAB in both groups together with SAB level.

The PI valuses in the finger and toe were elevated post-SAB in both groups; it showed no significant difference between them. However, in the Ce group, anesthesia immediately reached the upper thoracic nerves, and blood pressure showed a significant decrease post-SAB.

Post-SAB finger PI value measuerments may not be useful for early detection of high SAB. Alternatively, the anesthesiologist should pay attention to immediate post-SAB changes in clinical signs such as a decrease in blood pressure as well as a rapid elevation of block level.