Pressure Injuries and skin microclimate

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A pressure injury is a localised injury to skin and/or underlying tissue usually over a bony prominence, as a result of pressure, or pressure in combination with shear.¹ Pressure injuries are believed to result from an interaction of compromised blood flow and deformation of soft tissue. Both pressure and shearing forces contribute to tissue deformation, with friction an important component of shear. An individual’s Tissue Tolerance is influenced by numerous intrinsic (physiologic) and extrinsic factors. Tissue tolerance is a critical component in determining whether a resident develops a pressure injury.^2,3

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Skin microclimate is the term used to describe the interaction between skin temperature and moisture at the skin surface.² When skin is wet, the stratum corneum becomes softer, more permeable and skin pH moves away from its normal acidic range into an alkaline state. Normal acidic pH is necessary for skin barrier function and repair! Wet skin is more likely to sustain mechanical damage from friction. This happens because the attachments between skin cells are weakened and frictional forces are increased in the presence of moisture. As a result, cells are more easily separated from each other. Heat is created and epidermal cells are rubbed away, triggering inflammation and repair.
Key risk factors include: immobility, limited activity and diminished sensory perception.⁴ Additional important risk factors include: presence of moisture, friction and presence of a medical device.
Pressure injuries that occur over bony prominences will correspond with the patient’s dominant position. Patients that spend the majority of their time in bed are most likely to exhibit ulcers over the sacro-coccygeal area, heels, and malleoli. Extremely thin patients and those with skeletal abnormalities are at special risk.^5,6 As you perform your head to toe assessment, observe and document skin condition over prominent bony prominences e.g. hypertrophic (prominent) joints, the scapulae (shoulder blades), posterior iliac spines (bones on either side of spine) or prominent vertebrae (spine) in the patient with kyphosis.
An alcohol-free barrier film can be applied to intact skin over buttocks and the sacrococcygeal area as well as other bony prominences to help prevent skin damage from friction and moisture.^7,8 3M™ Cavilon™ No Sting Barrier Film can be used for this purpose. Avoid use of barrier creams and ointments (e.g zinc oxide ) that can increase drag and friction on the skin.
Ask for Cavilon™ No Sting Barrier Film. Cavilon™ No Sting Barrier Film is like no other barrier film. The product’s unique 3M formulation contains a blend of not one but two polymers, including a Terpolymer and a Homopolymer (plasticiser). The Terpolymer is derived from three distinct monomers, that provides a protective coating on the skin, creating a highly effective barrier. The Homopolymer enhances the films ability to flex with the skin and helps to maintain a continuous, protective coating. Other barrier films contain only one polymer and some utilse alcohol as a solvent. For more information on Cavilon™ No Sting Barrier Film, visit our website: www.Cavilon.com.au.
References
1. Stechmiller JK, et al. Guidelines for the prevention of pressure ulcers. Wound Repair and Regeneration. 2008; 16: 151- 168.
2. International review. Pressure ulcer prevention: pressure, shear, friction and microclimate in context. A consensus document. London. Wounds International. 2010
3. Ayello EA, Baranoski S, Lyder CH, Cuddigan JE, Harris WS, Pressure Ulcers in Baranoski S. and Ayello EA. Wound Care Essentials. 3rd ed. Philadelphia, PA: Lippincott, Williams and Wilkins; 2012: 324-359.
4. Prevention Plus: Home of the Braden Scale. http://www.bradenscale.com/ http://www.bradenscale.com/images/ bradenscale.pdf Accessed 1/13/13.
5. Mimura M, Ohura T, Takahashi M, Kajiwara R, Ohuru N. Mechanism leading to the development of pressure ulcers based on shear force and pressures during a bed operation: influence of body types, body positions and knee positions. Wound Rep Regen. 2009; 17: 789-796.
6. Scott EM, et al. Measurement of interface pressures in the evaluation of operating theatre mattresses. J of Wound Care. 1999; 8: 437-441.
7. Ratcliff CR, Tomaselli N. Guideline for Prevention and Management of Pressure Ulcers. Wound Ostomy and Continence Nurses Society. 2010.
8. Registered Nurses Association of Ontario (RNAO). Risk assessment & prevention of pressure ulcers. Toronto (ON): Registered Nurses Association of Ontario (RNAO); 2005.
Article is sponsored by 3M.