Update on volume therapy in obstetrics

Area of Science:

• Anesthesiology
• Obstetrics
• Critical Care Medicine

Background:

• Symptomatic hypotension is a common complication of spinal anesthesia during cesarean delivery.
• Severe hypotension can adversely affect maternal and fetal outcomes.
• Current strategies involve adjusting fluid preloads and vasopressor use.

Purpose of the Study:

• To evaluate the efficacy of a mixed hydroxyethyl starch (HES) and Ringer's lactate (RL) preload compared to a pure RL preload in preventing hypotension during spinal anesthesia for cesarean delivery.
• To assess the impact of the fluid preload strategy on maternal and neonatal outcomes.

Main Methods:

• A multicenter, randomized, double-blinded trial (CAESAR trial) was conducted.
• Participants received either a mixed 500 ml 6% HES 130/0.4 + 500 ml RL preload or a 1 L RL preload.
• Hypotension was monitored, and maternal and neonatal outcomes were assessed.

Main Results:

• The mixed HES + RL preload significantly reduced the incidence of hypotension compared to the 1 L RL preload.
• No adverse effects on coagulation or neonatal outcomes were observed with the mixed preload.
• This strategy demonstrated improved management of spinal-induced hypotension in cesarean delivery.

Conclusions:

• A mixed HES and RL fluid preload is an effective strategy for reducing hypotension during spinal anesthesia for cesarean delivery.
• This approach offers a safe and effective alternative to traditional RL preloading, improving maternal and fetal well-being.
• The findings support a shift towards optimized fluid management in obstetric anesthesia.