Acute maternal confusion and neonatal seizure postpartum

A 32 year old nulliparous woman underwent induction of labour with dinoprostone at 41+2 weeks’ gestation. Her membranes were artificially ruptured after 24 hours and she requested an epidural before augmentation of labour. A litre of Hartmann’s solution was administered simultaneously with the epidural to correct any epidural-induced hypotension. A synthetic oxytocin (syntocinon) infusion (10 units/50 mL in sodium chloride 0.9%) was started at 2 cm cervical dilatation. She remained on intravenous fluid throughout her labour, receiving a further litre of fluid six hours later. At 8 cm cervical dilatation, a persistent fetal bradycardia warranted an emergency caesarean section. Estimated blood loss was 830 mL and she received 2 L of fluid intra-operatively.

She gave birth to a 3975 g baby girl with Apgar scores of 9 at one minute and 10 at five minutes. The mother received 10 units of oxytocin to achieve adequate uterine tone. A continuous infusion of 40 units of syntocinon in a litre of Hartmann’s solution was also administered over four hours as per hospital protocol.

At 4 hours of age, the baby had a tonic-clonic seizure lasting 40 seconds and the mother became acutely confused. The mother was clinically euvolaemic and computed tomography of the head was normal. Blood results are shown in table 1.

It later transpired the mother had drunk more than 4 L of fluid during labour, in addition to the 4 L given intravenously.