The four hour time frame for refrigerators is an expensive, ridiculous, overly conservative rule of thumb for folks that don't know any better - sort of like hospitals and how they treat diabetics to 'prevent' hypoglycemia.
It's far more reasonable to use a thermometer to actually measure the temp and only start to trash perishable stuff that has reached 40F for two hours or more. In my experience that is somewhere around 10-12 hours - in Florida in the summer during the daylight hours.
The freezer is good for at least 48 hours.
This coming from someone very distrustful of questionable food.
If insulin can last three years, or more, at 46F I'm pretty confident that it can withstand some 'brief' excursions at higher temps.
Plus, you can move some of the frozen stuff to the fridge to keep it cool. Keep an old milk jug full of frozen water in the freezer. It will extend the time quite a bit. When hunting, I use two such milk jugs in my 75 gallon cooler and it lasts about 48 hours.
The insulin can easily be moved into a cooler for long term power outages.