Objective: To determine the prevalence of fetal acidemia associated with regional anesthesia for elective cesarean delivery in healthy paturients with uncomplicated singleton term pregnancies.
Methods: This was an epidemiologic study using the data base of the Swiss obstetric study group (Arbeitsgemeinschaft Schweizerischer Frauenkliniken). After the exclusion of cases with extraneous factors that may have affected the health of the neonate, we analyzed the umbilical artery pH, Apgar score, and other neonatal outcome measures after cesarean delivery with reference to the anesthetic technique.
Results: From 1985 to 1994, 327,763 deliveries, including 40,858 (12.47%) by cesarean, were registered in the data base. Of these, 5806 patients fulfilled the study criteria. The study population included 1002 spinal, 2155 epidural, and 2649 cases of general anesthesia. The frequency of fetal acidemia (pH less than 7.10) was significantly increased in the spinal-anesthesia group (odds ratio [OR] 4.67; 95% confidence interval [CI] 2.73, 8.01) and in the epidural group (OR 2.39; 95% CI 1.42, 4.04) compared with the general-anesthesia group.
Conclusion: The rate of fetal acidemia is significantly increased after regional anesthesia. This risk must be judged in light of the risks inherent with general anesthesia.