PCA
noun medical specialized uk/ˌpiː.siːˈeɪ/ us/ˌpiː.siːˈeɪ/
[ U ]自控式镇痛（patient controlled analgesia的缩写）
abbreviation for patient controlled analgesia: a process in which patients suffering pain can control when and how they receive a drug to reduce their pain
[ C ]大脑后动脉（Posterior cerebral artery的缩写）
abbreviation for posterior cerebral artery: a blood vessel that supplies blood to the back of the brain