7.2 MASD/IAD, MARSI Prevention, and Skin Care Products
Key Takeaways
- Incontinence-associated dermatitis is moisture and irritant damage with irregular erythema in the perineum or folds; pressure injury is pressure or shear, usually over a bony prominence or under a device, and it can necrose and be staged.
- Use a gentle pH-balanced cleanser and pat dry; vigorous scrubbing strips the remaining epidermis and worsens incontinence-associated dermatitis.
- Barrier ointments (petrolatum, dimethicone, zinc oxide), no-sting polymer films, and liquid cyanoacrylate protect at-risk or denuded skin; containment (pouching or a fecal management system when indicated) beats barrier cream used alone on high-output liquid stool.
- Medical adhesive-related skin injury is prevented with silicone adhesives, a skin barrier under tape, application without tension, low-and-slow removal, and adhesive removers.
- Intertrigo is fold moisture plus friction; moisture-wicking textiles help, and satellite papules point to Candida that needs an antifungal, not only a barrier paste.
IAD versus pressure injury: get the etiology right before you pick a product
Moisture-associated skin damage (MASD) is inflammation and erosion from prolonged moisture and irritants. The CWCN exam repeatedly tests whether you can tell incontinence-associated dermatitis (IAD) from a pressure injury, because the plans diverge. IAD is chemical and moisture injury from urine, stool, or both. Pressure injury is ischemia from pressure, shear, or both, over a bony prominence or under a device. Independent OpenExamPrep practice items will give you a red buttocks picture and ask whether you stage it or you treat moisture.
IAD lives where effluent lives: perineum, buttocks, inner thighs, and groin, often in a “kissing” pattern on opposing surfaces. Edges are diffuse and irregular. Color is bright red on lighter skin and may be violaceous, darker, or just “not the person's usual tone” on richly pigmented skin. The person often reports burning or stinging. There is no necrotic eschar at the start. Do not stage IAD. Staging is a pressure-injury language. A pressure injury is typically over a heel, sacrum, trochanter, ischium, or under a device, with a more distinct border that often mirrors the bone or the device. It can have nonblanchable deep discoloration, undermining, or necrosis. Moisture and pressure can coexist on the same sacrum; treat both, but do not hide a pressure injury by calling it “just dermatitis,” and do not put a person on a turning-clock-only plan when the real driver is unmanaged liquid stool.
Other MASD cousins belong in the same mental drawer. Periwound maceration is white, soggy skin from wound exudate. Intertriginous dermatitis (intertrigo) is fold moisture plus skin-on-skin friction. Peristomal moisture injury is a related problem on ostomy skin and is taught in depth in ostomy content; the product logic (protect, contain, do not scrub) still applies.
Cleanse, then protect: products that match the skin you see
Healthy skin sits near pH 4.5 to 5.5. Alkaline bar soap, perineal washcloths used like sandpaper, and hydrogen peroxide “to clean the rash” all delay barrier recovery. Use a gentle pH-balanced no-rinse cleanser, no vigorous scrubbing, and pat dry. Liquid stool is more damaging than urine because fecal enzymes (proteases and lipases) digest skin. Formed stool is easier to contain than high-output liquid stool; the product plan must match output, not a unit's default cream.
Barrier choices:
- Petrolatum is occlusive and inexpensive. It can melt in folds and is a weak plan as the only defense against liquid stool.
- Dimethicone (a silicone) is more breathable, often easier to assess through, and a common choice for intact at-risk skin.
- Zinc oxide pastes are durable against liquid effluent. They are opaque, so you must remove them to inspect—use mineral oil or an emollient, not a scouring pad. Zinc left caked in a fold becomes a moisture trap.
- No-sting polymer / acrylate barrier films paint a thin film on intact or mildly injured skin and are a standard layer under adhesives.
- Liquid cyanoacrylate polymerizes on denuded, painful IAD and can last days. It is a skin protectant, not a pressure-injury dressing and not an excuse to skip containment.
Containment is a skin intervention. High-output liquid stool or a fistula may need pouching. An indwelling fecal management system is for selected people with liquid stool when the rectum can accept the device and bleeding, sphincter, and sphincter-tone cautions are respected; it is not a default for every incontinent person and not for formed stool. Absorbent briefs that stay wet against the skin recreate a moisture chamber. Change them on a schedule and after output, and do not treat “the cream” as a substitute for getting stool off the skin.
| Finding | Favors IAD | Favors pressure injury |
|---|---|---|
| Location | Perineum, folds, inner thighs, often bilateral | Over bone or under a device |
| Borders | Irregular, diffuse | More distinct, may mirror bone or device |
| Tissue | Erythema, erosion; no eschar at onset | May have necrosis, undermining, deep discoloration |
| Symptom | Burning, stinging | May be painless if insensate |
| Staging | Do not stage | Stage using pressure-injury definitions |
| First moves | Cleanse, contain, barrier or film | Offload, redistribute, treat moisture if also present |
A person with diarrhea has bright, irregular erythema across the buttocks and perineum, burning pain, and no necrotic tissue. Which interpretation is most accurate?
MARSI: the adhesive is the etiology
Medical adhesive-related skin injury (MARSI) is erythema, stripping, blistering, erosion, or dermatitis that persists after an adhesive is removed, caused by the adhesive—not by pressure and not by urine. Types you must separate at the bedside:
- Skin stripping: epidermis peels off with the tape or dressing.
- Tension injury / blister: tape was stretched on application or the tissue swelled under a fixed tape.
- Maceration under occlusive adhesive.
- Folliculitis or irritant / allergic contact dermatitis in the exact footprint of the product.
Fragile skin (age, steroids, edema, dehydration), repeated dressing changes, and aggressive acrylate tapes raise risk. Prevention is a sequence, not a brand name:
- Choose silicone adhesives when skin is fragile or the dressing will be changed often.
- Paint a no-sting barrier film under adhesives on intact skin so the glue bonds to the film more than to the stratum corneum.
- Apply without tension. Do not stretch tape “so it stays.”
- Remove low and slow, supporting the skin adjacent to the adhesive, in the direction of hair growth.
- Use an adhesive remover (silicone-based removers are gentler than harsh solvents) rather than ripping.
- Do not stack layers of tape, and do not use extra-strong cloth tape as a default on older arms.
If you need a dressing to stay on an edematous leg, the answer is a correctly sized product and a wrap that accounts for volume change—not more tensile force on the skin. Contact dermatitis from a topical is not MARSI, but it is a neighboring iatrogenic injury: the map of the rash matches the product, not a bony prominence.
Intertrigo and Candida
Intertrigo is inflammation in a skin fold from trapped moisture, heat, and skin-on-skin friction. Under breasts, pannus, groin, and natal cleft, the skin looks moist, red, and macerated. Separate the fold. Use moisture-wicking textiles designed for skin folds rather than gauze that mats into a wet rope. Avoid talc and cornstarch; powder cakes and cornstarch can feed yeast.
Candida is the common secondary infection. The exam clue is satellite papules or pustules around the main rash. Treat with an appropriate antifungal and keep the fold dry; zinc paste alone does not treat yeast. Bacterial intertrigo can coexist; worsening pain, odor, or spreading cellulitis is not “just yeast.” Do not label fold injury as a Stage 2 pressure injury unless pressure or shear is actually the driver—most inframammary and pannus injuries are MASD until proven otherwise.
Clinical scenario
A 78-year-old with tube-feeding diarrhea has denuded, bleeding perineal skin. Staff have been using a soapy washcloth “to get the barrier cream off,” then reapplying a thin petrolatum. The skin worsens. The plan that matches this chapter is: stop the scrub, cleanse with a pH-balanced no-rinse product, contain liquid stool (pouch or a fecal management system if the person is a candidate), and protect denuded skin with a durable zinc paste or a liquid cyanoacrylate rather than a melting petrolatum film. Tape a foam dressing over the buttocks only if you can apply and remove it without creating MARSI—silicone, barrier film, low and slow. If satellite papules appear in the groin fold, add an antifungal and a moisture-wicking textile. Do not stage the IAD, and do not treat it with a total contact cast.
Which technique best prevents medical adhesive-related skin injury when removing tape from older, edematous skin?
A moist inframammary fold has a central shiny red patch surrounded by satellite papules. What is the most appropriate next step?
High-output liquid stool is denuding the perineum despite a thin petrolatum layer. Which plan addresses the driver?