Table 1 Characteristics of common polymeric dressings
From: Evaluating polymeric biomaterials to improve next generation wound dressing design
Dressing Class | Polymer Component(s) | Natural or Synthetic | Bacteria/Infection Controla,b, c | Permeabilityd | Exudative/Moisture Control | Wound Types | Limitationse | Commercial Products |
|---|---|---|---|---|---|---|---|---|
Loose-Weave Gauze (Dry/Wet) | Cellulose-derived | Natural | • Dry: Outside-In - External barrier protection dependent on thickness and fiber weave • Wet: Inside-Out - Bacterial removal dependent on external absorptive gradient | Non-Occlusive; Fiber weave and thickness can alter permeability | • Absorptive; aids in removal of exudate. Wetness, coating, and fiber weave alter absorption. • Wet-to-Dry: A technique where premoistened gauze creates an Inside-Out moisture gradient (frequent dressing changes). | • Moderate-to-Highly exudative wounds. Wound protection as a secondary dressing in many wound types. | • Dry: Reinjury of tissues upon removal if enmeshing occurs. Requires dressing change when exudate absorption "strikes through" to outer surface. • Wet-to-Dry: Requires dressing change every few hours to maintain moisture gradient or is prone to bacterial overgrowth. | Surgical Gauze and Kerlix® |
Fine-Mesh Gauze (Coated/ Uncoated) | Cellulose-derived | Natural | Inside-Out - Dependent on secondary dressing for external absorptive gradient. | Semi-permeable; Tight fiber weave (traditional 44/36; warp/weft) reduces permeability. | • Uncoated: Absorptive, although single ply is thin without much capacity, requiring secondary dressing which must then be changed. • Coated: Maintains moisture when coated with hydrophobic ointments, preventing drying and reducing scabbing. | • Wounds that are shallow and superficial. • Often used for promoting re-epithelialization, of which coated fine-mesh gauze is often ideal. | • Uncoated: Requires secondary dressing. Can become incorporated in scab. • Coated: Still requires secondary dressing but maintains moisture and reduces scab. Decreased absorptive properties. | Scarlet Red®, Xeroform®, Vaseline Gauze |
Films | Polyurethane, Silicon, Nylon, Polyester, or Polyethylene | Synthetic | Outside-In - External barrier protection | Semi-Permeable or Occlusive | Non-absorptive; traps moisture within wounds. Permits moisture vapor transpiration. | • Dry-to-Minimally exudative wounds. • Secondary external dressing to hold other dressings. | • Moisture trapping can result in tissue maceration and bacterial overgrowth. • Minimal mechanical protection. • Pain upon removal due to adhesion. | Tegaderm®, Covaclear®, Opsite®, Darmatac® |
Foams | Polyurethane, Silicone, and Polyvinyl Alcohol | Synthetic | Variable - Dependent on pore size and hydrophobicity | Variable (typically Permeable-to-Semi-Permeable) | Variable absorptivity; dependent on hydrophobic moisture gradient. PVA will dry to rigidity if exposed to air. | • Can be used on most wound types, though typically utilized with Moderate-to-Highly exudative wounds. • Composite dressing are common for foams. | • Can trap bacteria within the foam dressing. • Can dry out some wounds. • More rigid foam dressings can induce tissue injury at a micron level. Reinjury of tissue upon removal due to enmeshing. • Requires wound monitoring and dressing changes every 1-7 days. | Allevyn®, Granufoam®, Optifoam®, Aquacel®, Bioatain®, Polymem®, Hydrofera Blue® |
Alginates | Mannuronic and Guluronic Acid | Natural | Inside-Out - Dependent on inherent antimicrobial properties | Permeable or Semi-Permeable | Highly Absorbent; aids in removal of exudate and moisture from wounds. | • Moderate-to-Highly exudative wounds. • Can be used to promote re-epithelialization. | • Can cause excessive drying of wounds. • Often require secondary dressing to hold in place. | Kaltostat®, Algisite®, Sorbsan®, Seasorb® |
Hydrocolloids | Silicone or Polyurethane backing. Carboxymethylcellulose (CMC), pectin, or gelatin colloid layer | Natural or Synthetic | Outside-In - External barrier protection | Semi-Permeable or Occlusive | Moderate Absorption; can remove wound exudate while also donating moisture to wounds via colloidal gel. | • Dry-to-Minimally exudative wounds. | • Colloidal gel can breakdown in wounds via hydrolytic and enzymatic activity. • Requires monitoring of wound and dressing changes every 5-10 days. | Replicare®, Duoderm®, Exuderm®, Comfeel® |
Hydrogels | Variable (Cellulose, Alginate, Polyethylene Glycol, Polymethacrylate) | Natural or Synthetic | Minimal - Dependent on secondary dressings and added antimicrobials | Permeable or Semi-Permeable | Minimal absorption; though provide moisture to wounds. | • Dry-to-Moderately exudative wounds. • Complex and deeper wounds. | • Can over saturate wounds and cause maceration. • Prone to hydrolytic and enzymatic degradation in exudative wounds. • Typically must be paired with additional dressings due to minimal mechanical or adhesive properties. | Amerigel®, Aquaflo®, Aquaform®, Intrasite®, Nu-gel® |