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.