Implications of Continuous Noninvasive Finger Cuff Arterial Pressure Device Use during Cesarean Delivery for Goal-Directed Fluid Therapy Preload Optimization: A Randomized Controlled Trial

Abstract

Background. Although fixed-volume conventional fluid preloading protocol fails to attenuate postspinal hypotension during cesarean delivery, the effect of goal-directed fluid therapy (GDFT) remains less explored. Continuous noninvasive finger cuff arterial pressure monitoring using devices such as the ClearSight System can provide the noninvasive stroke volume value, enabling clinicians to perform GDFT before spinal anesthesia; however, the efficacy of GDFT requires further elucidation. Method. In total, 71 consecutive full-term pregnant women were randomly divided into a control group ( $n=34$ ) and a GDFT group ( $n=37$ ). Before spinal anesthesia, the control group received a fixed dose (1000 mL) of crystalloid fluid, but the GDFT group received repeated 3 mL/kg body weight of crystalloid fluid challenges within 3 minutes with a 1-minute interval between each fluid challenge based on the stroke volume incremental changes obtained using the ClearSight System (targeting a stroke volume increase of ≥5% after a fluid challenge). The primary outcome was the incidence of postspinal hypotension. The secondary outcomes were total fluid volume, vasopressor dosage, hemodynamic parameter changes, maternal adverse effects, and neonatal profiles. Result. Women in the GDFT group received more fluid than did those in the control group ( $1132\pm 108$ vs. $1247\pm 202$  mL; $p=0.0044$ ), but the incidence of postspinal hypotension (79.4% vs. 73.0%,; $p=0.5864$ ) and norepinephrine dose ( $12.5\pm 10.6$ vs. $15.1\pm 12.8$  mcg, respectively; $p=0.3512$ ) was comparable between the two groups. Fewer women in the GDFT group experienced nausea (61.76% vs. 35.14%; $p=0.0332$ ). Neonatal outcomes (Apgar score and umbilical blood analysis) were comparable and typical in both groups. Conclusion. ClearSight-guided GDFT did not ameliorate postspinal hypotension but may reduce nausea. This trial is registered with NCT03013140.