How do I know if the wound on my back is infected?

Contact your provider right away for blisters, a new open sore, foul odor, pus, redness and tenderness, warm or swollen skin near the sore, or fever. On the back, also watch for friction against the sheet and report any dark purple or maroon patch, even with unbroken skin.

The back is one of the bony areas where pressure sores form, along with the buttocks, elbows, hips, heels, ankles, shoulders and the back of the head. For a wound here, the signs to watch for are the ones for pressure sores.

Contact your provider right away if you develop blisters, an open sore, or any signs of infection, such as a foul odor from the sore, pus coming out of the sore, redness and tenderness around the sore, skin close to the sore that is warm or swollen, or fever.

What’s different about the back is friction, not just pressure. Avoid further injury or friction by lightly dusting your bedsheet with medicated talc powder to prevent further friction between your skin and the sheet. Only do this if your pressure sore is not an open wound. And avoid slipping or sliding as you move positions. Read the condition on that first tip carefully: it does not apply if the sore is open.

Position still matters too. If you are in bed, you should move or be moved about every 2 hours.

There is one look worth knowing about at this site, because it does not look like a wound at all. Some pressure sores develop in the tissue deep below the skin. This is called a deep tissue injury. The area may be dark purple or maroon. There may be a blood-filled blister under the skin. This type of skin injury can quickly become a stage III or IV pressure sore. A dark purple or maroon patch on the back, with the skin still intact, is worth reporting rather than waiting to see whether it opens.

What to watch for

Contact your provider right away if you develop blisters, an open sore, or any signs of infection, such as a foul odor from the sore, pus coming out of the sore, redness and tenderness around the sore, skin close to the sore that is warm or swollen, or fever. If your pressure sore changes or a new one forms, tell your provider.

Two things specific to this site are worth reporting without being asked. First, any dark purple or maroon area where the skin has not broken. That is the deep tissue injury described above, and it is not something to watch quietly. Second, how the person is moved. Sliding up the bed rather than being lifted is the friction to avoid, and it is easier to change than almost anything else here.

What we look at

  • Which infection signs are present, and when each appeared
  • Whether any dark purple or maroon area is present with intact skin
  • Friction and shear during transfers and repositioning
  • Repositioning interval achieved in bed
  • Whether talc is being used on an open wound, contrary to the instruction

Sources

  1. MedlinePlus — How to care for pressure sores: https://medlineplus.gov/ency/patientinstructions/000740.htm