RESUMEN
We present a case of a probably unnecessary Caesarean section due to misinterpretation of the cardiotocography (CTG) trace during general anaesthesia. A 27-yr-old patient in her 30th week of an uneventful, normal first pregnancy presented with a deep venous thrombosis in the pelvic region. She was to undergo an emergency thrombectomy under general anaesthesia. During the operation, the CTG showed a lack of beat-to-beat heart rate variation (silent pattern CTG) with normal fetal heart rate. This silent CTG pattern was probably a result of the effect of general anaesthesia on the fetus. The CTG pattern was interpreted as indicating fetal distress, and an emergency Caesarean section was performed after the thrombectomy. The infant was apnoeic and had to be resuscitated and admitted to the neonatal intensive care unit. The pH at delivery was 7.23 and the baby was extubated 2 days later. Mother and child recovered without short-term sequelae. In the absence of alternative explanations, reduced fetal beat-to-beat variability with a normal baseline heart rate during general anaesthesia is probably normal.
