[Case of acute dystonia during epidural droperidol infusion to prevent postoperative nausea and vomiting]

We report a case of bilateral ocular deviation due to droperidol-induced acute dystonia that was initially undiagnosed. A 22-year-old, 72 kg, parturient at 42 weeks' gestation underwent emergency cesarean section for pregnancy-induced hypertension under combined spinal-epidural analgesia. The epidural catheter was inserted through the T11-12 interspace, followed by intrathecal hyperbaric bupivacaine with adjunctive fentanyl. The patient complained of nausea shortly after delivery, which subsided with intravenous droperidol 1.25 mg and metoclopramide 10 mg. After surgery, epidural infusion with a mixture of ropivacaine, fentanyl, and droperidol was started. Around 25 hours postoperatively, both of the patient's eyes rotated upwards, although she was fully conscious. Brain CT/MRI did not show any abnormalities. An ophthalmologist and a neurosurgeon were consulted but there was no definitive diagnosis. On subsequent consultation with anesthesiologists, it was assumed that the symptom was related to external ophthalmoplegia secondary to spinal anesthesia. Thereafter, a "wait and see" approach was adopted. After 8 hours, she gradually developed torticollis and increased muscle tone of the lower extremities, which facilitated a diagnosis based on extrapyramidal signs. Epidural infusion was discontinued without further treatment. Her symptoms completely disappeared within 5 hours. The estimated cumulative dose of intravenous and epidural droperidol was 4.6 mg over 34 hours.