Background and Goal of Study: Theoretically technique which was purposed to augment cardiac output (CO) in a term pregnancy who receive subarachnoid blockade (SB) for cesarean section (CS) is the left uterine displacement maneuver (LUD). However, benefit of the LUD to intraoperative hemodynamic profiles had never been clarified. Goal of this study is to compare differences in hemodynamic profiles of term pregnancies who underwent cesarean section with- vs. without LUD maneuver.

Materials and Methods: We studied hemodynamic profiles in sixty term-pregnancies who underwent elective CS under SB using non-invasive CO monitor (NexfinTM). All 60 patients were randomized into two groups, which were LUD group (received 15-30 degree of LUD after SB, n=30) and non-LUD group (no LUD after SB, n=30). Patient’s hemodynamic variables including systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), CO, systemic vascular resistance (SVR), and left ventricular contractility index (dP/dT) were measured continuously since pre-SB till the end of surgery. Primary outcome was incidence of maternal systolic hypotension within 5-min following SB, secondary outcome were differences in intraoperative hemodynamic variables between two groups of patients. Incidence of maternal systolic hypotension analyzed using a Chi-square test, and differences in hemodynamic profiles between two patient groups analyzed using Mann-Whitney U test.

Results and Discussion: While there was no difference in baseline characteristics between two groups of patients, the patients in LUD groups had significantly lower incidence of maternal systolic hypotension (16.7%) than patients in non-LUD group (53.3%) (p=0.003) (Fig.1). In pre-fetal delivery phase, patients in LUD groups had significantly higher CO (7.2 vs. 6.3 L/m, p=0.016) (Fig.2), higher dP/dT (806 vs. 583 mmHg/sec, p=0.02), and lower SVR (818 vs. 909 dynes.s.cm-5, p=0.04) than patients in non-LUD groups. In post-fetal delivery phase, the patients received LUD had significantly lower MAP (74 vs. 83 mmHg, p=0.03) and lower SVR (670 vs. 729 dynes.s.cm-5, p=0.03), while there was no difference in CO and HR between two groups.

Conclusions: In term pregnancy patients who received SB for elective CS, performing LUD was associated with lower incidence of maternal systolic hypotension. Potential benefits to cardiovascular system of LUD was confined in pre-delivery phase.

08 / Analysis of hemodynamic profiles in term pregnancies receiving subarachnoid blockade for cesarean section: A randomized comparison trial between left uterine displacement vs. without left uterine displacement maneuver.