Hi jhk56,
You could have a look at cople of solutions various ManageEngine partners have built that might help you.
The MEPlugins is a plattform that improves various features of ServiceDesk Plus but also integrate ServiceDesk with number of other system, https://www.meplugins.com/collections/mepsdp/products/multi-notifications
If you have number of users who work only from time to time within ServiceDesk Plus and are using Outlook as their e-mail client you might want to look into https://www.vlink.is/Products/V-Technician but with this great product your users would never need to work from within ServiceDesk Plus, all work can be done from Outlook.
Hope this can help.
Regards,
/Thorir