The aim of the article was to investigate the effect of ondansetron preloading with crystalloid infusion after spinal anesthesia during cesarean delivery.
A total of 66 parturient women scheduled for elective caesarean sections were randomly assigned to two groups. Five minutes before spinal anesthesia, Group O patients were injected with 4 mg of ondansetron, while Group S patients were injected with 5 mL physiological saline. Maternal blood pressure and heart rate were measured at 2 minute intervals for 30 minutes. After delivery, umbilical cord blood samples were analyzed.
Maternal hypotension and nausea were significantly lower in ondansetron-treated patients versus placebo (p = 0.011 vs. 0.004). Umbilical venous pH was significantly higher in ondansetron-treated patients (p = 0.006), while partial pressure of carbon dioxide (Pco 2) was significantly lower (p = 0.002). Decreases in maternal systolic and mean arterial blood pressures were significantly lower in ondansetron-treated patients (p = 0.008 vs. 0.025), with less requirement for phenylephrine administration compared with controls (p = 0.029).
Ondansetron preloading combined with crystalloid infusion significantly reduced hypotension and nausea, while improving acid-base status, as well as reducing vasoconstrictor use.