Whew!! So glad he's doing ok. I agree with Rene in respect to them "doing" without fretting over it.  The sling is a great way to compensate.  If you've never done it,  you'd be shocked at how much easier it makes things.  If you have a Voyager,  I think the extra head and elbow room may make it easier for your gentle giant. 

Couple of things to keep in mind.  Many times larger animals take a little more time to ambulate well.  Recovery can also take more time.  Keeping him calm and resting him for  the next couple of weeks will be so important.  

Sleep,  quick potty breaks,  food,  and hydration will be your goal for now.  No running,  jumping,  walks,  or couches.  

Medication... please give it at regular intervals.  It may need tweaking as anesthesia wears off over the next 4-5 days.  The pain meds can throw off his appetite.  Make sure you have things he likes.  Hamburger,  roasted chicken,  cheese,  scrambled eggs,  whatever he loves.  Worry about regular food after,  ok? He may do just fine but better to be prepared.

If you can get some puppy pads to place over his bed it can help in cause he has an accident.  Easier to replace a pad than  to have to wash a whole  xxl dog bed

Lots of docs start at a lower level of pain meds.  Sometimes it works,  sometimes they need to increase some. Keep in contact with your doc and keep them in the loop. 

I know,  I just threw a bunch of stuff to you,  but I'm hoping to prepare you as best as I can for whatever may come  your way. 

Get rest,  make your home ready for recovery.  This can be a bit of a rollercoaster ride but don't forget we're here.  Stay tuned and don't forget to breathe

Hugs 

Jackie and Huck❤