Ondansetron preloading with crystalloid infusion reduces maternal hypotension during cesarean delivery.

OBJECTIVE

The aim of the article was to investigate the effect of ondansetron preloading with crystalloid infusion after spinal anesthesia during cesarean delivery.

STUDY

DESIGN

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.

RESULTS

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).

CONCLUSION

Ondansetron preloading combined with crystalloid infusion significantly reduced hypotension and nausea, while improving acid-base status, as well as reducing vasoconstrictor use.