I am often asked whether to use heat or ice after an injury. Some controversy exists, and you should always follow the advice of your doctor. Often these recommendations are based on what feels best. Also, ice can sometimes reduce the time it takes for you to recover from an injury, or even just a tough workout.
The general rule is to apply cold in the first 12 to 24 hours. During this time period, inflammation is peaking, and ice will help reduce this swelling. On the other hand, heat will increase blood flow and potentially increase the swelling. However, after the first day, heat will encourage healing with better blood flow.
On the more extreme side of things, some athletes will immerse a limb, or even their lower body, into an ice bath. Marathoners are notorious for such practices. Whether a result of a sprained ankle or a superhuman workout, take caution when immersing body parts into extreme cold. Limit the time to five minutes and never immerse your chest. If you have heart or other serious medical conditions, avoid this practice altogether.
In terms of post-op recovery, the same principles apply. Cold is best shortly after the procedure. Naturally, if heat feels better, by all means, apply heat. Of course, always ask for your doctor’s advice.