You should change the bandage daily, or anytime it becomes wet or soiled.  Each time you change the bandage, gently wash and dry the area, and reapply antibiotic ointment to the site. Continue to bandage the blister until the skin has healed completely. It is common for a blister to itch as it heals, especially if it is allowed to dry out, but it is important not to scratch it and risk further skin damage.  Keeping the area cool and wet is one way to decrease itching.  Soak a clean cloth in ice water, and apply it to the site, or soak the area in a tub of cool water.  Be sure to clean the area, reapply antibiotic cream and bandage it again afterwards. If the skin around the bandage becomes red, bumpy, or itchy, you may have an allergy to the adhesive in the bandage (or the bandage itself). Try a different brand, or try nonstick sterile gauze pads and medical tape. You can apply hydrocortisone 1% ointment to the irritated skin around the blister to help with itching, but don’t apply it to the blister itself. Once the skin underneath the blister has had a chance to heal and is no longer tender, you can safely trim away the skin flap over it using a pair of clean, sanitized scissors. Open blisters can become infected easily, so pay close attention to them as they heal.  If you notice any signs of infection, or if your blister isn't beginning to recover within a few days, seek medical attention.  Signs of infection include:  Increased pain around the blister. Swelling, redness, or warmth near the blister. Red streaks on your skin heading away from the blister; this is a sign of blood poisoning. Pus draining from the blister. A fever. Many blisters will heal naturally on their own, given a little time. However, there are some cases in which you should see your doctor for a blister as soon as possible. You should seek prompt medical attention if your blisters:  Are infected (see the previous step for signs of infection) Are causing a lot of pain Keep returning Occur in unusual places, such as the inside of the...

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Write a summary of the previous text in Vietnamese:
Thường xuyên thay đổi miếng dán trên vết phồng rộp. Xử lý cảm giác ngứa khi vết phồng rộp lành. Lấy miếng da bị bong ra sau khi vết thương không còn đau. Lưu ý dấu hiệu viêm nhiễm. Chăm sóc y tế cho vết phồng rộp.