Rosalyn Jordan, RN, BSN, MSc, CWOCN, WCC

Are all blisters pressure ulcers and if they are, how should they be staged?

All blisters are not pressure ulcers. A pressure ulcer is defined as a “localized injury to the skin and/or underlying tissue as a result of pressure, or pressure in combination with shear.”

An initial resident assessment should include a pressure ulcer risk assessment and skin assessment. The risk assessment should provide information related to mobility, nutrition, moisture, sensory perception and general health status.

Because a blister is considered a wound, an assessment must be completed. This assessment will provide data regarding location of the wound, temperature of the skin, edema or swelling, and any change in the texture of the skin surrounding the wound or the blister. Location of a blister is extremely relevant when determining if the blister is related to pressure. Blisters associated with pressure usually are located over a bony prominence. Pressure from medical devices on the skin may cause blisters considered pressure ulcers.

If the blister is intact and filled with a clear, serum-like fluid, this should be considered a Stage II Pressure Ulcer. Likewise, if the blister has ruptured or is an open wound, this is a Stage II Pressure Ulcer. Both are considered partial thickness wounds.

A blister that is filled with a bloody fluid is defined as a “Suspected Deep Tissue Injury: Depth Unknown,” according to the NPUAP. These areas may progress rapidly and advance to full thickness pressure ulcers.

Because a physician must diagnose any wound, the nurse should refer all blisters to the care of a physician. 

The National Pressure Ulcer Advisory Panel Consensus Conference on Pressure Ulcer Staging is April 8-9, 2016, in Rosemont, IL.