I try to avoid video newscasts in general, as there's a high probability of encountering imagery that I won't be able to get out of my head. A couple of times a day I check the headlines of a couple of news websites, and read a handful of articles on issues that interest me.
There's very little chance of completely missing out on an important news story, because if it's that important a lot of people will be talking about it. Unless there's something that you yourself have to do immediately (for example, finding shelter because dangerous weather is coming), even the top headlines can wait.