Moisture-Associated Skin Damage (MASD): Skin breakdown caused by prolonged exposure to moisture (urine, feces, perspiration, or wound exudate). Presents as superficial damage with diffuse, irregular borders and is often erythematous, macerated, or denuded. Frequently misclassified as pressure injury, though management strategies for the 2 differ substantially.  

Pressure Injury: Tissue damage resulting from sustained pressure, often combined with shear, typically localized over bony prominences or beneath medical devices. Unlike MASD, severity can extend from intact skin to full-thickness tissue loss.  

Incontinence-Associated Dermatitis (IAD): A subtype of MASD resulting from prolonged exposure to urine and/or feces, most commonly affecting the perineal and buttock regions. Enhanced urea conversion to ammonia during dual incontinence raises skin pH and accelerates barrier breakdown.  

Medical Adhesive-Related Skin Injury (MARSI): Skin injury caused by adhesive products removing superficial layers of the epidermis during dressing changes, resulting in erythema, skin stripping, pain, and delayed healing. Risk increases with frequent dressing changes and fragile or aging skin.  

Maceration: Softening and breakdown of the stratum corneum caused by prolonged hyperhydration, commonly from wound exudate or other moisture sources. Macerated skin has a higher coefficient of friction, making it more vulnerable to mechanical injury.  

Stratum Corneum: The outermost layer of the skin, composed of protective lipids that maintain barrier function. Excess moisture causes hyperhydration and maceration of this layer, while harsh cleansers or alkaline products can strip its protective lipids.  

Transepidermal Water Loss (TEWL): The rate at which water passively evaporates through the skin barrier to the environment. Moisturizers help reduce TEWL, supporting hydration, elasticity, and barrier resilience, which is particularly important in older adults and patients with fragile skin.  

Humectants: A class of moisturizing ingredients (eg, glycerin, hyaluronic acid, urea) that draw water into the stratum corneum from the environment and deeper skin layers.  

Emollients: A class of moisturizing ingredients (eg, ceramides, fatty acids, dimethicone) that fill gaps between skin cells, smoothing texture and reinforcing the skin’s lipid barrier.  

Occlusives: A class of moisturizing ingredients (eg, petrolatum, mineral oil, lanolin) that form a surface layer to slow water loss, especially useful on very dry or fragile skin.  

Cleanse–Moisturize–Protect Framework: A structured, repeatable approach to skin care built around 3 sequential steps: cleansing to remove irritants and debris without stripping natural lipids, moisturizing to replenish hydration and support barrier lipids, and protecting to shield vulnerable skin from moisture, friction, and irritants.