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Laceration repairs in pediatric patients ideally should be quick and painless, be strong and resistant to infection, promote healing, and yield good cosmetic outcomes. Tissue adhesives offer these advantages and are a wise choice for children who present with minor, low-tension wounds, especially on the head and face.
Each year more than 7 million patients seek emergency department (ED) care for traumatic lacerations, and more than 2 million lacerations occur in patients aged younger than 18 years.1
Not only are pediatric patients disproportionately affected, but they pose a specific set of challenges to physicians charged with caring for their wounds. Younger patients may have increased anxiety about needles and painful procedures and are typically less likely than their older counterparts to remain still during evaluation and repair.
Regardless of the patient’s age, proper wound care is essential for reducing infections and promoting healing. Although copious “higher”-pressure irrigation is the best means to remove foreign matter and reduce bacterial load, good skin apposition and closure are also required to prevent further bacterial contamination and infection as well as produce the best cosmetic outcome.
In selecting a method of wound closure, today’s provider has an armamentarium of choices including sutures, staples, adhesive strips, and adhesive glues.
These methods not only differ in their intrinsic properties but also in their application, required skill, amount of pain caused, and duration of the procedure.
Because of the added challenges associated with treating the pediatric patient, the ideal method of closure in this population would be easy, quick, and painless and would not require a second visit for removal. Of course the closure must also produce sufficient tensile strength, have a low risk of infection, and result in a good cosmetic outcome.
As a method of laceration repair, skin adhesives offer many of these advantages, including minimal pain, intrinsic antibacterial activity, and good cosmetic results.
Despite these beneficial properties, skin adhesives are still limited from comprehensive use by their lesser tensile strength. However, they remain a good choice for pediatric patients, whose wounds are more likely to be short and linear and in areas of low tension, such as on the head or face.2
History of tissue adhesives
Most tissue adhesive glues used today are from a family of molecules known as cyanoacrylates. A German chemist synthesized the first cyanoacrylate in 1949.3
Initially, cyanoacrylates were marketed for commercial (nonpharmaceutical) purposes (eg, Krazy Glue). It was not until the 1970s that cyanoacrylates became available for clinical use in Canada, Europe, Israel, and the Far East.4
The US Food and Drug Administration (FDA) first approved 2-octyl cyanoacrylate (DermaBond) for use in 1998.5 Over the following years, other cyanoacrylates (Indermil and Histoacryl, both n-butyl-2 cyanoacrylates) garnered FDA approval for humans.6,7 Tissue adhesives are now widely used in both operative surgical closures as well as ED laceration repairs.
The family of cyanoacrylates is formed from the endothermic reaction of an alkyl cyanoacetate and formaldehyde to form an alkyl cyanoacrylate monomer. When the monomer comes into contact with water on the skin surface, it polymerizes into long chains, forming a film. Over time, the cyanoacrylate polymer degrades via hydrolysis back into an alkyl cyanoacetate and formaldehyde, both of which can be histotoxic.4
Like many organic compounds, the physical properties of the alkyl cyanoacrylate monomers and resulting polymers largely depend on the nature of their alkyl side chains. A short side chain (ie, methyl or ethyl) results in a very reactive monomer that quickly polymerizes into a film. Unfortunately, these bonds are subject to rapid hydrolysis and degrade quickly, releasing toxic products.8
A longer side chain (ie, butyl or octyl) produces a more stable monomer. Although these monomers may be slower to polymerize, polymerization results in a bond that degrades more slowly.8 When used as a skin adhesive, the longer chain cyanoacrylates typically undergo little in situ degradation and instead slough off with the outer layer of skin over time, minimizing the release of histotoxic byproducts.4
Early studies using cyanoacrylates for wound repair involved administering the adhesive directly into the wound.9 This technique produced good tensile strength during the initial days after administration. As time progressed, however, the presence of adhesive glue within the wound acted as a foreign body that prevented apposition of tissue and appropriate healing. A significant inflammatory reaction occurred, resulting in frequent wound dehiscence.
Current technique stresses the importance of avoiding application of the glue directly into the wound. Instead, the wound edges should be manually approximated first and the adhesive then applied as a film over the top. This method allows the adhesive to act as an outer bridge, holding the layers of skin together as wound healing
Since the first cyanoacrylates were used clinically, there have been several randomized, controlled trials in the pediatric population comparing the cosmetic outcome of wounds closed with Histoacryl to wounds closed with sutures. For example, as early as 1993, Quinn and colleagues enrolled 81 children and adolescents (aged 0-18 years) with facial lacerations that were less than 4 cm in length and less than 0.5 cm in width, not requiring deep layer closure.10
Later similar studies continued to evaluate skin adhesive as a method of pediatric laceration repair.11-13 There were no significant differences in cosmetic outcome between Histoacryl and sutures when scars were compared at 2 to 3 months and again at 12 months. In addition, secondary endpoint analyses showed skin adhesives to be significantly faster in application than standard suture wound closure and significantly less painful than sutures, despite the use of an anesthetic (injected lidocaine or topical tetracaine-epinephrine-cocaine) when necessary. There were no significant differences in rates of infection or dehiscence.
In a study of DermaBond versus sutures, Quinn and associates enrolled 130 adults with face, torso, or extremity lacerations, regardless of the laceration’s length or need for deep sutures.14 Again, there was no significant difference in cosmetic outcome at 3 months. As with Histoacryl, application of DermaBond was faster and less painful than the standard suture alternative.
Subsequently, Osmond and colleagues reported an interadhesive comparison between Histoacryl and DermaBond in 94 children and adolescents with simple facial lacerations.15 Despite differences in butyl versus octyl side chain and method of application, there were no significant differences between groups for time of repair, ease of procedure, pain score, infection rate, dehiscence rate, or cosmetic outcome at 3 months.
Finally, Zempsky and associates compared DermaBond to reinforced Steri Strip skin closures in 97 children and adolescents with short, low-tension facial lacerations and found no significant differences in procedural pain or cosmetic outcome at 2 months.16 However, there was a trend (P=.06) toward fewer short-term complications, specifically infection and dehiscence, in the Steri Strip group.
Despite the many advantages of skin adhesives, they remain restricted in use because of their limited tensile strength. The aforementioned studies, which claim equal rates of wound dehiscence, must be interpreted with caution, because entry criterion generally precluded inclusion of large, high-tension wounds.
Using guinea pigs to compare Histoacryl to percutaneous sutures, Noordzij and associates found a drastic difference in wound strength between groups immediately after repair: sutures proved 12 times stronger than adhesive.17 However, after 7 days of healing and after suture removal, there was no significant difference in breaking strength.
Also in a guinea pig model, Bresnahan and colleagues compared wound strength in 4 groups: Nexaband liquid (n-butylcyanoacrylate) alone, Nexaband liquid with a single subcutaneous suture, percutaneous sutures alone, or percutaneous sutures with a subcutaneous suture.18
Ninety-six hours after closure, wounds repaired with adhesive glue alone had significantly lower tensile strength than those closed with any of the other 3 methods. Although the addition of a subcutaneous suture increased the tensile strength of the adhesive, the insertion of stitches begins to eliminate the many benefits of using
Shapiro and associates used fresh porcine skin to compare, in vitro, the tensile strength just after placement of 4 common wound closure methods: DermaBond, surgical staples, Steri Strips, or interrupted, subcuticular 4-0 sutures.19 Staples proved significantly stronger than sutures or DermaBond, and sutures or DermaBond proved significantly stronger than Steri Strips. However, the increased strength of the sutures versus DermaBond did not reach significance in this study.
It has been suggested that DermaBond (which also contains plasticizers) is stronger and more pliable in vivo than Histoacryl.20 However, a published report of a direct tensile strength comparison in an animal model could not be located. Furthermore, Osmond and colleagues’ interadhesive comparison of Histoacryl and DermaBond in pediatric patients showed no differences in dehiscence rates.15
Although copious irrigation remains paramount for preventing wound infection, there are also data to suggest that at least some of the cyanoacrylate products exhibit intrinsic bacteriostatic activity (beyond their sealant effect), which may help keep infection rates low.
For example, using an in vitro agar-plating technique, Chen and associates demonstrated that both Histoacryl and a methoxypropyl cyanoacrylate created zones of growth inhibition against Staphylococcus aureus, Streptococcus pneumoniae, and Mycobacterium chelonae.21 However, these adhesives had no such inhibitory effect on Escherichia coli or Pseudomonas aeruginosa.
Noordzij and colleagues inoculated guinea pig incisions with S aureus before closure and found decreased bacterial counts in wounds closed with Histoacryl compared with sutures on day 4.17
In a 2-part experimental design( in vivo in guinea pigs and in vitro in soy broth), Howell and associates investigated cyanoacrylate liquid and obtained similar antibacterial results against S aureus.22
How to use
Only certain lacerations are appropriate for skin adhesive repair. The cyanoacrylates are best used on short, linear, low-tension wounds that can be manually approximated easily. Lacerations in areas of high tension, such as over joints or on the hands or feet, should be avoided. Similarly, moist areas, such as the mucous membranes, perineum, and axillae, prevent adequate adhesion. Crush injuries and stellate lesions can be difficult to approximate.
After initial evaluation of the wound, a topical anesthetic formulation such as lidocaine, epinephrine, and tetracaine solution should be applied as soon as possible. In most studies, topical anesthetics have proven to be at least as effective for pain control as lidocaine infiltration.23 Topical anesthetics have the added benefit of needleless, nearly pain-free application, which is especially good for children. Administering the anesthetic early in the patient’s care relieves pain sooner and provides analgesia before irrigation.
General wound care is unchanged. Copious high-pressure irrigation is key to removing foreign matter and preventing infection. Using a syringe with a splashguard helps optimize this procedure. Traumatic lacerations should be irrigated with approximately 100 cc per 1 cm length of laceration or an even larger volume when significant contamination is likely. The patient’s tetanus immunization status should be addressed.
Skin adhesive application
After hemostasis, irrigation, and patting dry, the wound edges are manually apposed. The adhesive should be applied to the outer surface of the skin, forming a bridge-like film across the defect. Care must be taken to avoid administering the adhesive directly into the wound, which actually prevents skin edge contact and healing.
DermaBond is applied via a porous applicator tip (supplied by the manufacturer) across the skin edges, which are held in place for another 30 seconds to allow for drying. This process is repeated with 2 to 3 additional layers, holding for 30 seconds between each; Histoacryl is applied as drops of glue across the skin edges and held in place for 30 seconds.
A common complication of skin adhesive application is leakage of glue into nearby, unintended areas. With use of adhesive for facial lacerations, leakage into the eye is of particular concern. To help prevent inadvertent lid margin and ocular involvement, position the patient so that any seeping of product will occur away from the eye. A ridge of petroleum jelly can also be applied between the laceration and eyelid to act as a barrier.
In the event glue does affect the eye, avoid using water to wipe the glue away because the polymerization of glue may be accelerated by water. Copious application of antibacterial ophthalmic ointment (ie, erythromycin ophthalmic ointment) may help break down the adhesive. An ophthalmologist should be consulted as necessary.
There is no need for antibacterial ointment because the adhesive has antibacterial properties and because the emollient ointment can cause premature loosening of the glue and wound dehiscence. Generally, there is no need for a dressing. If cotton gauze is requested, it is imperative that the polymerization reaction has completed and that the glue is completely dry. There is a case report of contact between cyanoacrylate household glue and cotton pajamas causing a severe exothermic reaction and full thickness burn injury.24
Patients should be instructed to keep their wounds clean and dry for the first 24 hours, after which they can shower, taking care not to overly soak the wound. Obviously, picking at the adhesive should be avoided to reduce the risk of dehiscence.
Important to remember
We want to thank Karen Quaal, PhD; Paul Sue, MD; Brittany Finocchio; Wayne Reisig, MLS; and Anne Wondisford for their help in the preparation of this manuscript.