Objective: Spinal anesthesia-induced hypotension (SAIH) is relatively common in pregnant women and has serious maternal and fetal side effects. In patients who are hypovolemic during spinal anesthesia, there may be a significant decrease in blood pressure caused by the decrease in preload. Subclavian vein sonography is a useful method for evaluating preoperative intravascular volume status. This study aimed to evaluate the efficacy of the pre-operative subclavian vein or infraclavicular axillary vein (SCV-AV) collapsibility index for predicting SAIH in cesarean-section (C-section).
Patients and methods: In this prospective observational study, 82 women undergoing elective C-sections were recruited. Sonographic evaluation of SCV-AV was assessed before spinal anesthesia. After spinal anesthesia, changes in blood pressure were noted. The main outcome was the association between the SCV-AV measurements (diameter and collapsibility index) and SAIH.
Results: Hypotension developed in 53 (64%) patients after spinal anesthesia. The collapsibility index of the SCV-AV during spontaneous breathing and deep inspirium was not a significant predictor of a decrease in mean blood pressure (MBP) after spinal anesthesia (p<0.979, p<0.380).
Conclusions: It was found that the SCV-AV collapsibility index is not a predictor of SAIH in pregnant women undergoing elective C-sections.