Worried that cold packs to fat grafts have affected their viability

We encourage our patients to apply cool packs (55-60 degrees) to help with the discomfort and swelling from fat grafting. Lower temperatures nearer to the freezing point may in fact harm these delicate grafts (that is the concept of Coolsculpt to eliminate fat with cryolipolysis). It is my opinion that you should stop the ice until you are able to speak with your surgeon

I think it's highly unlikely that you would have damaged the graft.
In order for the temperature to get low enough to actually damage the tissues you would've been in a significant amount of discomfort.
Tissues kept it low temperatures have an extremely slow metabolism and can be kept alive for many many more days then at the body temperature.
There's not a lot of scientific research showing that cooling the tissues after fat transfer as a positive or negative results.
 Personally I believe immobilization and avoiding pressure on the treated areas is the most important after how the fat is harvested and injected.
Best,
Mats hagstrom, MD