Is it possible to create my own custom SQL 'trigger' with Powershell?

I'm familiar with MSSQL triggers already, however they aren't fine grained enough for what I want to do. In my scenario I want the trigger to fire after a row containing certain information lands in the table; not every time an UPDATE is performed.

I've used Powershell scripts to 'listen' for files dropping in a certain location, and then sending an email, I'm just wondering if this is at all possible with MS SQL server?