Is there a way to set up Communication SLAs (time between updates to clients)?

Is there a way to set up Communication SLAs (time between updates to clients)?

I know there is a way to set up Resolution SLAs (time to resolve the request), but I also want to track if our staff is providing clients with updates while the case remains unresolved (open).  How can this be done? 

For instance, we would like to ensure that our clients receive an update from our staff every 2 hours for a Priority 1 case, every 2 days for a Priority 2 case, etc.