Cyanosis and cardiovascular depression in a neonate: complications of halothane anesthesia or phenylephrine eyedrops?

A 3-week-old patient underwent cataract extraction under halothane anesthesia. After induction of anesthesia and instillation of phenylephrine hydrochloride eyedrops, the patient experienced cyanosis and cardiovascular depression. Her condition improved over the next 10 minutes. The possible contributions of halothane and phenylephrine to this response are discussed.