Ice the trouble spot with an ice pack or a bag of frozen veggies for 20 minutes, every 4 to 6 hours.

每隔4到6个小时，用冰袋或者蔬菜冷冻袋冰敷伤口20分钟。

youdao

If there's no fridge, pack your lunch in a small insulated lunch bag with an ice pack.

如果没有冰箱的话，那就把你的午饭装在加了冰块的小保温袋里。

youdao

For current pain, you may find relief from over-the-counter pain medicines or using a cold pack (such as an ice pack or a bag of frozen vegetables wrapped in a thin towel) applied periodically to your chest.

CNN: How can I make my mammogram hurt less?