The median ( range ) number of physician interventions needed to maintain maternal hemodynamics within the target range ( @ -LSB- @-@ -RSB- vs @ -LSB- @-@ -RSB- , difference in median : @ , @ % confidence interval of difference : @-@ ) and incidence of hypotension ( @/@ -LSB- @ % -RSB- vs @/@ -LSB- @ % -RSB- ) were lower in group P compared with group S ( P < @ ) .