In the last three decades, numerous interventions have been studied and implemented into our daily practice, such as pre-loading versus co-loading, phenylephrine versus ephedrine, and phenylephrine infusion versus intermittent boluses. In addition, the effectiveness of left uterine displacement (LUD) to improve blood flow and pressure remains unclear. Also, there are issues to be addressed on this regard, including:~Poor placental perfusion from inadequate LUD due to the potential impact of supine hypotensive syndrome (SHS) secondary to aortocaval compression especially after SAB;~Shivering during cesarean delivery (CD) resulting in inaccurate BP measurements, the incidence of shivering during CD is reported to be 21.9%. It is unclear the impact of shivering during CD on blood pressure (BP) measurements;~Patient discomfort during BP measurements, calf > arm > ankle~The Investigators are conducting a single center prospective self-control study aiming to validate the effectiveness of LUD after SAB with simultaneous measurements of BP on the arm and left ankle during surgery in patients undergoing cesarean delivery (CD). In addition, the Investigators will determine whether ankle BP correlates more accurately than arm SBP with the incidence of nausea/vomiting and category II or III fetal heart tracing and bradycardia after SAB and LUD under no shivering conditions and the impact of body mass index and antepartum estimation of newborn weight on SHS after the SAB.
This is a single center prospective self-control study to validate the effectiveness of left uterine displacement after subarachnoid block (SAB) with simultaneous measurements of blood pressure (BP) on the arm and left ankle during surgery in patients undergoing cesarean delivery (CD) at The Ohio State University Wexner Medical Center