be scared out of one's wits 狼狈周章；仓皇失措；慌了神儿；失魂落魄；被吓得魂飞魄散

【例句】
A cat suddenly screamed out, I was scared out of my wits.
一只猫突然大叫起来，把我吓得魂飞魄散。

I was scared out of my wits by a loud noise in the middle of the night.
半夜一声巨响，我被吓得魂飞魄散。