WOUND CAREBy

Jocelyn M. Lledo, MDPlastic Surgery Fellow-in-Training

BRIEF HISTORY OF DRESSINGS

• Homespun remedies – ritualistic teachings, observations

• “Three healing gestures” - (circa) 2200 BC on an ancient clay tablet – (1) washing the wound,– (2) making plasters (mixtures of herbs, ointments,

and oils that were applied to wounds to aid in the healing process), and

– (3) bandaging the wound

• Lister (1867) - first antiseptic dressings– soaked lint and gauze in carbolic acid (phenol)

before applying them to wounds• Tulle gras - one of the earliest nonadherent

dressings; popular in World War I; gauze impregnated with paraffin

• Owens (1944) - fine mesh gauze as minimally adherent intermediary underlying more absorptive materials

• References to early wound care in: – Bible, ‘‘. . .went to him, and bound his wounds,

pouring oil and wine’’ (Luke, 10:34); – Ancient Assyrian writings, ‘‘. . . the surface of the

sick part with butter you shall anoint. . .’’; and– Ancient Greek texts, ‘‘With bandage firm, Ulysses’

knee they bound’’ (Homer, The Odyssey)

DESIRABLE DRESSING CHARACTERISTICS

• Protect wound from bacteria and foreign material• Absorb exudate from wound• Prevent heat and fluid loss from wound• Provide compression to minimize edema and

obliterate dead space• Be nonadherent to limit wound disruption• Create a warm, moist occluded environment to

maximize epithelialization and minimize pain• Be esthetically attractive

• Scab formation– Alternative to dressing– Nature’s dressing– Crusts of dried serum with trapped erythrocytes,

platelets, and other blood-borne cells

• Advantages:– Barrier against foreign

material – Reduction of pain– Holding wound edges in

approximation– Facilitation of wound

contraction– Minimizing loss of fluid

and proteins

• Disadvantages:– Can fix bacteria on

wound surface infection

– Slow epithelialization

ACUTE WOUND CARE

• Patient information– Tetanus immunization status– Bleeding at the time of injury– Medical Illnesses– Smoking history

• Examining the wound– Need for debridement– Cleansing the wound: irrigate

• Evaluate for any underlying injury– Vascular, nerve, tendon injury– Fracture or joint dislocation

• Further treatment

CONCEPT OF OCCLUSION

• Before: wounds kept dry, as advocated by Pasteur to keep them ‘‘germ-free’’

• Winter: effects of occlusion on the rate of epithelialization (1962)– Porcine model surgically created wounds left to

heal either open to air or occluded under a transparent film

– Rate of epithelialization under the occlusive dressing twofold that of wounds left undressed

• Occlusive dressings: – Limit transmission of fluids, water vapor, and gasses from the

wound bed to the external environment– Maintain a mildly acidic pH and a relatively low O2 tension on

the wound surface– Prevents desiccation, which leads to cell death– Facilitates epidermal migration, angiogenesis, and connective

tissue synthesis– Supports autolysis of necrotic material by providing the solute

for enzymatic debridement– Limit pain associated with partial thickness wounds to a much

greater degree than nonocclusive dressings

• Low O2 tension– Angiogenesis, an important factor in wound

healing– Optimal conditions for fibroblast proliferation and

granulation tissue formation • Cytokines– Granulation tissue formation and epithelialization – More likely to be preserved in an occluded wound

environment

SPECIAL WOUND REQUIREMENTS

• Infected or heavily contaminated wounds – Occlusive dressing bacterial proliferation, infection

exacerbation– Dressing that diminishes bacterial count

• Heavily exudative wounds– Priority: degree of absorption of excessive exudate

that no occlusive dressing can provide– Large amounts of exudate skin maceration around

wound, dilute intrinsic factors such as cytokines retarded healing

• Dressing regimens that contribute to wound debridement– Wounds with nonviable tissue– Wounds with foreign bodies or debris

• Wounds involving toxins (brown recluse spider bites or infiltrated chemotherapeutic agents)– Debridement to limit ongoing damage by the toxic

agent– Surgical debridement generally required

DRESSING OPTIONS

• NONADHERENT FABRICS

• ABSORPTIVE DRESSINGS – Foams– Gauze

• OCCLUSIVE DRESSINGS– Nonbiologic dressings – Biologic dressings

• CREAMS, OINTMENTS, AND SOLUTIONS– Antibacterial agents,

acetic acid, Dakin’s solution, iodine-containing antibacterials, silver-based dressings, wound debridement

• MECHANICAL DEVICES

NONADHERENT DRESSINGS

• Derivatives of fine mesh Owens gauze and tulle gras

• Consist of fine mesh gauze with a supplement provided to augment – its occlusive properties– its nonadherent properties– its healing-facilitating capabilities– its antibacterial characteristics

• Hydrophobic: – Scarlet Red – Vaseline gauze– Xeroform – Telfa

• Hydrophilic:– Xeroflo – Mepitel – Adaptic – N-terface – Fine mesh gauze

ABSORPTIVE DRESSINGS

• Wide mesh gauze• Foams– Lyofoam – Allevyn– Curafoam– Flexzan – Biopatch – Vigifoam – Mepilex

OCCLUSIVE DRESSINGS

• Benefits: – Insulation– Moisture retention– Mechanical protection– Barrier function against bacteria

• Nonbiologic– Films– Hydrocolloids– Alginates– Hydrogels

• Biologic– Allograft– Xenograft– Amnion– Skin substitutes (Integra,

Dermagraft, Apligraf, Alloderm)

FILMS

• Clear polyurethane membranes with acrylic adhesive on one side for adherence

• Advantages:– Waterproof but allow the transmission of oxygen,

carbon dioxide, and water vapor– Generally transparent wounds visualized easily– Extremely thin do not interfere with patient

function

• Disadvantages: – Nonabsorptive fluid collection leaks out,

disrupting antibacterial seal, messy– Intact skin surrounding area being dressed needed

for dressing adherence– Wound contraction may be slowed – Removal of film can disrupt new epithelium

• Tegaderm, Mefilm, Carrafilm, Bioclusive, Transeal, Blisterfilm, Op-Site

HYDROCOLLOIDS

• Family of dressings containing a hydrocolloid matrix composed of such materials as gelatin, pectin, and carboxymethylcellulose

• Contact with wound exudate matrix absorbs water, swells, and liquefies moist gel

• Ability to absorb wound exudate – Products vary in absorption capacity

• May or may not leave a residue in the wound

• Generally opaque• Advantages:– Limited moisture and gas transmission – Impermeability to bacteria

• Slightly bulkier than films– May provide more protection for the wound– May interfere with function to a greater degree

• Available as adhesive wafers or as pastes or powders

• Duoderm, NuDerm, Comfeel, Hydrocol, Cutinova, Tegasorb

ALGINATES

• Composed of soft, nonwoven fibers of a celluloselike polysaccharide derived from the calcium salt of alginic acid (seaweed)

• Primary use in exudative wounds• Contact with wound exudate insoluble

calcium alginate partially converted to a soluble sodium salt hydrophilic gel as by-product occlusive environment that facilitates healing

• Packaged in a variety of forms, including ropes for packing cavities, ribbons for narrow wounds or sinuses, and pads

• Algiderm, Algosteril, Kaltostat, Curasorb, Carasorb, Melgisorb, SeaSorb, Kalginate, Aquacel, Sorbsan

HYDROGELS

• Consist of a starch polymer, such as polyethylene oxide, or a carboxymethylcellulose polymer and up to 80% water

• Function as rehydrating agents for dry wounds • Because of their high water content, they do

not absorb large amounts of wound exudate

• Available as gels, sheets, or impregnated gauze

• Vigilon, Nu-gel, Tegagel, FlexiGel, Curagel, Flexderm

BIOLOGIC OCCLUSIVE DRESSINGS

• Homograft - graft transplanted between genetically unique humans

• Xenograft - graft transplanted between species– Pigskin - most commonly used xenograft

• Homografts and xenografts - temporary dressings (both are rejected if left on a wound for an extended period)

• Amnion - derived from human placentas; use has diminished with increased concern regarding biologic materials

• Alloderm and Integra– Include components that are incorporated into

healing skin – Considered skin substitutes

• Biobrane - a biosynthetic dressing constructed of a silicone film with a nylon fabric embedded into the film– Nylon fabric is constructed of a trifilament thread

to which collagen is chemically bound

CREAMS, OINTMENTS, SOLUTIONS

• Broad category – zinc oxide paste– preparations containing growth factors – enzymatic debriding agents– free radical scavengers (allopurinol, dimethyl

sulfoxide)– agents to decrease platelet aggregation (iloprost)– agents that bind growth factors (sucralfate)

• Many designed to have antibacterial properties

ANTIBACTERIAL AGENTS

• Commonly used to treat infected wounds• Acetic acid– Dilute acetic acid (vinegar) – Ancient therapy still used today– Effective against gram-negative organisms, such as

Pseudomonas– Slow down wound epithelialization and to limit

polymorphonuclear neutrophil function

• Dakin’s solution– Hypochlorite solution, dilute bleach– Initially described by Labarraque in 1820– Popularized by Dakin in 1915– Broad antibacterial spectrum, although toxic to

fibroblasts– Slower to epithelialize and neovascularize than

wounds treated with less toxic solutions

• Iodine-containing antibacterials– Include 5% and 10% povidone-iodine ointment

and cadexomer iodine gel (Iodosorb and Iodoflex)– Broad antibacterial and antifungal spectrum– Betadine: most toxic of all agents tested on

fibroblasts– Impaired wound healing, reduced wound strength,

or promoted infection

• Silver nitrate– Used in the Middle Ages for cautery and, in high

concentrations (3% to 8%), for hypertrophic granulation tissue

– Broad antibacterial spectrum– Can slow epithelialization– Hyponatremia and hypochloremia sec. to

hypotonicity– Stains bedclothes and all it touches black– Methemoglobinemia

• Mafenide (Sulfamylon)– Broad antibacterial spectrum– Ability to penetrate eschar– Disadvantages: occasional pain on application,

inhibition of epithelialization, and inhibition of carbonic anhydrase, which can lead to metabolic acidosis

– Disadvantages minimized while maintaining antibacterial efficacy by using a 5% solution placed on dressings three to four times a day

• Silver sulfadiazine (Flammazine)– Broad spectrum of antibacterial, antifungal, and

antiviral activity– Limitations: transient neutropenia, occasional

topical sensitivity – Accelerate epithelialization of partial-thickness

wounds– Increase in neovascularization – Most commonly used antibacterial agent in burn

wound management

• Acticoat– Silver-impregnated dressing– Occlusive and promotes a moist healing

environment – Broad spectrum of antibacterial activity that

persists for 3 days, eliminating the need for frequent dressing changes

– More effective antibacterial than silver nitrate in a comparative study of burn wounds

• Mupirocin– Derived from Pseudomonas fluorescens– Inhibits protein synthesis within bacteria– Primarily active against aerobic gram-positive

cocci, including streptococcal species, S. aureus, Staphyloccocus epidermidis, and methicillin-resistant S. Aureus

– Does not impair epithelialization or wound contraction

• M.E.B.O.– Moist Exposed Burn Ointment– Composed of beeswax and sesame oil as the main

active ingredients– Used in burn regenerative therapy

WOUND DEBRIDEMENT

• Sharp debridement - time-honored approach to removing devitalized and necrotic tissue from wounds

• Clearly demarcated areas of living versus dead tissue - required to avoid damaging healthy tissue and to minimize patient discomfort

• Biologic debridement, wet-to-dry technique, nonmechanical debridement

• Biologic debridement with sterile maggots (fly larvae) – Centuries-old technique enjoying a resurgence in

popularity– Sterile maggots fiercely consume necrotic tissue

and reject viable tissue – Secrete peptide antimicrobials (defensins),

providing an antimicrobial benefit

• Wet-to-dry debridement technique– Surgical standard where wound is cleansed and

packed with saline-moistened gauze– As the wound and gauze dry, fibrinous exudate

generated hardens and adheres to the gauze– Non-discriminating: any adherent material

removed can slow the progress of the healing wound and cause pain

• Nonmechanical debridement – Can be provided by absorptive and enzymatic

agents– Dextranomer polysaccharide: anhydrous, highly

porous beads that trap bacteria and debris at the dextranomer layer of the wound-dressing interface

– Dressing changes effectively diminish the bacterial counts in wounds

• Enzymatic debridement– Naturally occurring compounds that degrade

complex molecules– Enzymes induce chemical reactions without being

changed or consumed themselves– Sutilain: an enzyme derived from the bacterium

Bacillus subtilis; digests soft necrotic tissue composed primarily of denatured collagen

– Collagenase (Santyl): from Clostridium histolyticum; digests denatured collagen and native collagen

– Papain: a vegetable pepsin prepared from the juice of the fruit and leaves of carica papaya; effective against collagen in the presence of a cofactor containing a sulfhydryl group (e.g. urea)

– Fibrinolysin: degrades fibrinous tissue– Deoxyribonuclease: degrades DNA and nuclear

proteins

MECHANICAL DEVICES

• Augment functions normally provided by dressings in wound management

• VAC device – most widespread utility– Enhance local blood flow, diminish edema, limit

bacterial proliferation, accelerate granulation tissue formation in wounds

– Facilitate complete wound closure or to prepare the wound for a reconstructive procedure

• Uses a reticulated foam dressing that is cut to conform to an individual wound

• Foam covered by an occlusive drape under which a vacuum tube is placed and connected to a pump, which provides 50 to 125 mm of negative pressure to the occluded wound environment

CHOOSING A DRESSING• Ovington: six basic questions to help guide the

choice of wound dressing:– What does the wound need?– What does the product do?– How well does it do it?– What does the patient need?– What is available?– What is practical?

• Important: – Continually assess wounds with each dressing

change – Adjust the wound care regimen as necessary to

accommodate the evolving condition

• Incisional wound– Three layer dressing– Ointment– Occlusive dressing

• Partial thickness wounds (e.g., abrasions, donor sites)– No dressing (scab)– Impregnated gauze– Creams/ointments– Occlusive dressings

• Full thickness wounds e.g. pressure sores– Alginates or hydrogels- rarely applicable– Creams/gels (e.g., Silvadene, Flammazine)– Wet-to-dry dressing changes– VAC device

THANK YOU