wound closure technique professor magdy amin riad professor of otolaryngology. ain shames university...

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.