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Wound Closure Technique
Professor Magdy Amin RIAD
Professor of Otolaryngology. Ain shames University
Senior Lecturer in OtolaryngologyUniversity of Dundee
Three phases of wound healing
• Three phases of wound healing have been identified and studied on the cellular and molecular level.
• These 3 distinct phases, ie, inflammation, tissue formation, and tissue remodeling, depend on an elaborate cascade of growth factors and cellular components interacting in a directed manner to achieve wound closure
The inflammatory phase
• The initial injury leads to the recruitment of inflammatory cells into the wound, once a clot forms in response to disrupted blood vessels.
• This scenario entails a complex interaction between local tissue mediators and cells that migrate into the wound.
The inflammatory phase
• The inflammatory phase occurs in the first few days as inflammatory cells migrate into the wound.
• Migration of epithelial cells has been shown to occur within the first 12-24 hours, but further new tissue formation occurs over the next 10-14 days
Epithelialization and neovascularization
• Epithelialization and neovascularization result from the increase in cellular activity.
• Stromal elements in the form of extracellular matrix materials are secreted and organized.
Epithelialization and neovascularization
• This new tissue, called granulation tissue, depends on specific growth factors for further organization to occur in the completion of the healing process.
• This physiologic process occurs over several weeks to months in a healthy individual.
Tissue remodeling
• Finally, tissue remodeling, in which wound contraction and tensile strength is achieved, occurs in the next 6-12 months.
• Systemic illness and local factors can affect wound healing.
• Traditionally, at least 2 types of wound healing have been described, ie, primary intention and secondary intention.
Primary intention
• In the primary intention method, surgical wound closure facilitates the biological event of healing by joining the wound edges.
• Surgical wound closure directly apposes the tissue layers, which serves to minimize new tissue formation within the wound.
• However, remodeling of the wound does occur, and tensile strength is achieved between the newly apposed edges.
Primary intention
• Closure can serve both functional and aesthetic purposes.
• These purposes include elimination of dead space by approximating the subcutaneous tissues, minimization of scar formation by careful epidermal alignment, and avoidance of a depressed scar by precise eversion of skin edges.
Primary intention
• If dead space is limited with opposed wound edges, then new tissue has limited room for growth.
• Correspondingly, atraumatic handling of tissues combined with avoidance of tight closures and undue tension contribute to a better result.
Secondary intention
• The secondary intention method (spontaneous healing)
• It can be used in lieu of complicated reconstruction for certain surgical defects.
• This method also depends on the 3 stages of wound healing to achieve the ultimate result.
Absorbable sutures
• Absorbable sutures are applicable to a wound that heals quickly and needs minimal temporary support.
• Their purpose is to alleviate tension on wound edges.
• The newer synthetic absorbable sutures retain their strength until the absorption process starts.
• Nonabsorbable sutures offer longer mechanical support.
Monofilaments
• Monofilaments have less drag through the tissues but are susceptible to instrumentation damage.
• Infection is avoided with the monofilament, unlike the braided multifilament, which potentially can sustain bacterial inocula.
• Gut is considered a monofilament
Natural materials
• Natural materials include gut, silk, and even cotton.
• Gut is absorbable, but cotton and silk are not.
• Gut is considered a monofilament, whereas silk and cotton are braided multifilaments.
synthetic materials
• The absorbable sutures include:
• monofilamentous Monocryl (poliglecaprone), Maxon (polyglycolide-trimethylene carbonate), and PDS (polydioxanone).
• Braided absorbable sutures include Vicryl (polyglactin) and Dexon (polyglycolic acid).
synthetic materials
• Nonabsorbable sutures comprise nylon, Prolene (polypropylene), Novafil (polybutester), PTFE (polytetrafluoroethylene), steel, and polyester.
• Nylon and steel sutures can be monofilaments or multifilaments.
• Prolene, Novafil, and PTFE are monofilaments. • Polyester suture is braided.
Absorbable suture tensile strength
• Absorbable suture materials lose their tensile strength before complete absorption.
• Gut can last 4-5 days in terms of tensile strength. In the chromic form (ie, treated in chromic acid salts), gut can last up to 3 weeks.
Absorbable suture tensile strength
• Vicryl and Dexon maintain tensile strength for 7-14 days, although complete absorption takes several months.
• Maxon and PDS are considered long-term absorbable sutures, lasting several weeks and likewise requiring several months for complete absorption
Non absorbable sutures tensile strengths
• Nonabsorbable sutures have varying tensile strengths and may be subject to some degree of degradation.
• Silk has the lowest strength and nylon has the highest, although Prolene is comparable.
Non absorbable sutures tensile strengths
• Both nylon and Prolene require extra throws to secure knots in place.
• Polyester has a high degree of tensile strength, and Novafil is appreciated for its elastic properties
surgical adhesives
• Use of surgical adhesives can simplify skin closure in that certain problems inherent to suture use can be avoided.
• Problems (eg, reactivity, premature reabsorption) can occur with sutures and lead to an undesirable result, both cosmetically and functionally.
surgical adhesives
• One substance, cyanoacrylate, has been used for 25 years and easily forms a strong flexible bond.
• It can induce a substantial inflammatory reaction if implanted subcutaneously.
• If used superficially on the epidermal surface, little problem with inflammation occurs
Octyl-2-cyanoacrylate (Dermabond)
• The only cyanoacrylate tissue adhesive approved by the U.S. Food and Drug Administration (FDA) for superficial skin closure.
• should not be implanted subcutaneously.
Octyl-2-cyanoacrylate (Dermabond)
• Subcutaneous sutures are used to take the tension off the skin edges prior to applying the octyl-2-cyanoacrylate.
• Subcutaneous suture placement will aid in everting the skin edges and minimize the chances of deposition of cyanoacrylate into the subcutaneous tissues.
Fibrin-based tissue adhesives
• Fibrin-based tissue adhesives can be created from autologous sources or pooled blood.
• They are typically used for hemostasis and can seal tissues.
• While they do not have adequate tensile strength to close skin, fibrin tissue adhesives can be used to fixate skin grafts or seal cerebrospinal fluid leaks.
Fibrin-based tissue adhesives
• Commercial preparations such as Tisseel (Baxter) and Hemaseel (Haemacure) are FDA-approved fibrin tissue adhesives made from pooled blood sources.
• These fibrin tissue adhesives are relatively strong and can be used to fixate tissues.
Fibrin-based tissue adhesives
• Autologous forms of fibrin tissue adhesives can be made from patient's plasma.
• The concentration of fibrinogen in the autologous preparations is less than the pooled forms; therefore, these forms have a lower tensile strength
Staples
• Staples provide a fast method for wound closure and have been associated with decreased wound infection rates.
• Staples are composed of stainless steel, which has been shown to be less reactive than traditional suturing material.
Staples
• The act of stapling requires minimal skin penetration, and, thus, fewer microorganisms are carried into the lower skin layers.
• Staples are more expensive than traditional sutures and also require great care in placement, especially in ensuring the eversion of wound edges.
• However, with proper placement, resultant scar formation is cosmetically equivalent to that of other techniques
Steri-Strips
• Used to ensure proper wound apposition and to provide additional suture reinforcement.
• These tapes can be used either with sutures or alone.
• Often, skin adhesives (eg, Mastisol, tincture of Benzoin) aid in tape adherence.
Basics of facial wound closure
• Good approximation of wound edges is paramount to proper wound closure technique.
• This may entail the placement of deep sutures subcutaneously or in the deepest layer of disrupted tissue; however, in some situations, a single-layer closure is adequate.
• When placing deep sutures, absorbables (eg, gut, Dexon, Vicryl, Monocryl) typically are used.
Basics of facial wound closure
• The knot is buried. • A clear permanent suture, either Prolene or nylon,
can be buried deeply in areas of tension. • All deep sutures serve to eliminate the dead space
and relieve tension from the wound surface. • Deep sutures also ensure proper alignment of the
wound edges and contribute to their final eversion
• Before placement of the sutures, wound closure may require sharp undermining of the tissues to minimize tension on the wound.
• Accomplish this maneuver by scalpel or scissors in the subdermal plane.
• Additionally, achieve hemostasis prior to wound closure to avoid future complications such as hematoma.
• Employ atraumatic skin-handling technique with instruments such as skin hooks and small forceps.
• Typically, a cutting needle is the needle of choice.
• Various curvatures are available depending on tissue depth.
• For wound closure in the head and neck region, small 5-0 or 6-0 sutures of nonabsorbable Prolene, nylon, or absorbable catgut are appropriate.
• Take great care to avoid tension during closure. • Likewise, avoid strangulation with the suture at the superficial skin
level. • Take the greatest care to ensure that wound edges not only are aligned
but also are everted. • Eversion of all skin edges avoids unnecessary depression of the
resultant scar. • With simple sutures, place knots away from the opposed edges of the
wound. • Normally, remove nonabsorbable suture after 4-5 days. In certain
situations, nonabsorbables can be removed at 10-12 days
Simple suture or everting interrupted suture
• Insert the needle at a 90° angle to the skin within 1-2 mm of the wound edge and in the superficial layer.
• The needle should exit through the opposite side equidistant to the wound edge and directly opposite the initial insertion.
• Oppose equal amounts of tissue on each side. • A surgeon's knot helps place the nonabsorbable suture. • Strive to evert the edges and avoid tension on the skin,
while approximating the wound edges. • Place all knots on the same side.
Simple running suture
• This suture method entails similar technique to the simple suture without a knotted completion after each throw.
• Precision penetration and tissue opposition is required. • The speed of this technique is its hallmark; however, it is associated
with excess tension and strangulation at the suture line if too tight, which leads to compromised blood flow to the skin edges.
• Another variant is the simple locked running suture, which has the same advantages and similar risks.
• The locked variant allows for greater accuracy in skin alignment. Both styles are easy to remove.
• Additionally, the running sutures are more watertight.
Mattress suture
• Vertical mattress sutures can aid in everting the skin edges.• Employ this technique also for attachments to a fascial layer. • The needle penetrates at 90° to the skin surface near the wound edge
and can be placed in deeper layers, either through the dermal or subdermal layers.
• Exit the needle through the opposite wound edge at the same level, and then turn it to repenetrate that same edge but at a greater distance from the wound edge.
• The final exit is through the opposing skin edge, again at a greater distance from the wound edge than the original needle entrance site.
• Place the knot at the surface. • A knot placed under tension risks a stitch mark.
The horizontal mattress
• The horizontal mattress can be used to oppose skin of different thickness.
• With this stitch, the entrance and exit sites for the needle are at the same distance from the wound edge.
Half-buried mattress sutures
• Half-buried mattress sutures are useful at corners.
• On one side, an intradermal component exists, in which the surface is not penetrated.
• Place the knot at the skin surface on the opposing edge of the wound.
Subcuticular suture
• Sutures can be placed intradermally in either a simple or running fashion.
• Place the needle horizontally in the dermis, 1-2 mm from the wound edge.
• Do not pass the needle through the skin surface. The knot is buried in the simple suture, and the technique allows for minimization of tension on the wound edge.
• In a continuous subcuticular stitch, the suture ends can be taped to the skin surface without knotting.