For all pressing matters, please contact [Contact Name] at [contact email] for assistance.
Seems like a big task, right? Well…wrong. You don’t need to stop by everyone in the office’s desks (if you’re even working in an office these days!) or send out an email to each and every client or lead. The easiest way to do this is by simply changing your voicemail greeting and adding an out-of-office email responder to your email client.

If instead you ask your co-workers to cc or bcc on replies then you will know which have been dealt with. (I think for internal mails it’s more reasonable to ask that if the original person contacts someone else, they cc you so you know who is dealing – and in smaller organisations where people know you personally you could also send a mail round the day before you leave to say you’re going to be out and to ask that any enquiries are directed to [name]in your absence, to try to avoid them coming into your inbox in the first place.
Because you can never predict when an emergency will come up, make sure you have someone who can resond to urgent requests. And that person would be your direct manager. But let them know ahead of time so they're not blindsided when they need to respond to something.