Summarize this article in one sentence.
Cold therapy (also called cryotherapy) can reduce your pain and inflammation, making you more comfortable and shortening your recovery time. However, people with certain conditions should not use cold therapy, so always discuss it with your doctor first. Some examples of contraindications of cold therapy include cold intolerance, cold urticaria, cryoglobulinemia, Raynaud disease, and a history of pyoderma gangrenosum. If you have any of these conditions, you should probably not use cold therapy. Your doctor will let you know how frequently you should use cold therapy, and for how long. Typically, post-operative patients use cold therapy during the first 48 hours after surgery, or sometimes for the whole first week, for about 20 minutes at a time. Cold therapy can also be useful after the immediate post-operative period, following physical therapy or exercise. Ask your doctor about this possibility as well. Cold therapy can come in the form of ice packs, gel packs, or motorized devices with wrap pads. Whichever you use, apply it outside your dressing, not directly to the skin.

Summary:
Talk to your doctor about the pros and cons of cold therapy. Follow your doctor’s instructions. Apply cold therapy outside your surgical dressing.