Preoperative femoral vessel variations in hypotension after spinal anesthesia for cesarean section

Abstract

Background Hypotension is a common side effect of spinal anesthesia during caesarean delivery. To assess the association between preoperative femoral vessel variations and postural hypotension after spinal anesthesia for cesarean section.Methods Participants who scheduled to undergo elective cesarean section with spinal anesthesia between November 2020 and June 2021 were included in this prospective study. Hypotension was systolic blood pressure decreased by at least 20% from baseline.Results Right femoral artery (RFA) peak flow velocity and the percent variance in the right femoral vein (RFV) in the left lateral decubitus position (LP) were significantly higher in the hypotension group than in the normal blood pressure group (P = 0.04 and P = 0.01). The percent variance in the RFV diameter in the LP (OR = 76.796, P = 0.016), preoperative basal heart rate (OR = 1.043, P = 0.028) were risk factors associated with hypotension during cesarean section, and weight gain during pregnancy (OR = 0.915, P = 0.047) was protective factor associated with hypotension during cesarean section. A cutoff value of 0.059% for the percent variance in the RFV had an AUC of 0.627 (95% CI: 0.508–0.757, P = 0.0045). Another cutoff value of 15.75 kg for weight change during pregnancy had an AUC of 0.617 (95% CI: 0.510–0.724, P = 0.038).Conclusions The percent variance in RFV diameter, preoperative basal heart rate and weight gain during pregnancy may be associated with postural hypotension after spinal anesthesia for cesarean section and should pay more attention in the clinical setting.Trial registration: Chinese Clinical Trial Registry (ChiCTR2000040029, 18/11/2020).