Fetal Heart Rate Changes Associated with General Anesthesia

Abstract

A 25-year-old woman developed right renal colic at 30 weeks' gestation requiring cystoscopy and basket extraction under general anesthesia. After a 48-hour period without narcotics and no premedication, anesthesia was induced with fentanyl 50 μg and thiopental 300 mg and maintained by mask with N2O 60%-O2 40%-halothane 0.5 to 1.0%. Total anesthesia time was 25 minutes. Maternal BP and HR remained stable throughout. Except during the time in lithotomy, the woman was kept in a left lateral posture.