Author: Dr. Nagesh Mandapaka*, Dr. Sheng Zhang#
*MBBS, MS - General Surgery at IRIS Multispeciality Hospital, Kolkata, #PhD – Chemistry VP - R&D (Adhezion Biomedical)download Article
Traditionally, most incision was closed by sutures but in recent times topical skin adhesive are being used frequently. Surgiseal, a topical skin adhesive offers many characteristics of a ideal wound closure device that is easy to use, rapid wound healer, painless, result in excellent cosmesis, not require device removal, and is cost-effective. Surgiseal (2-octylcyanoacrylate) provides the optimal balance between strength and flexibility with patented OctylFlex Technology. Surgiseal can replace suture that are 5-O or smaller in diameter for incision or laceration repair and is designed to save time during wound repair.The formulation leads to the scarless surgery with desired cosmetic results.
Keywords: Skin Adhesive, Surgiseal, scarless, painless, rapid wound healer, 2-Octylcyamoacrylate
Every year there are over 7 million traumatic lacerations  and between 26 to 90 million surgical incisions which requires closure by surgeons, emergency physicians, and primary care practitioners  Conventionally, these wounds and incisions were closed with sutures, staples, or surgical tapes, but in recent times tissue adhesives are being used frequently. Ideally, a wound closure device should be easy to use, rapid wound healer, painless, result in excellent cosmesis, not require device removal, and be cost-effective. Although none of the presently available closure devices meet all of these needs, but the topical cyanoacrylate tissue adhesives offer many of the characteristics of this ideal wound closure device .
Cyanoacrylates was first manufactured in 1949. The first adhesives were found to have an extreme inflammatory effects on tissues. N-butyl-2-cyanoacrylate, which was developed in the 1970s, became the first adhesive to have negligible tissue toxicity and good bonding strength, as well as acceptable wound cosmesis .
Surgiseal (2-octylcyanoacrylate), the latest in cyanoacrylate technology, has comparatively less toxicity and almost four times the strength of N-butyl-2-cyanoacrylate . It provides the optimal balance between strength and flexibility. Surgiseal can replace suture that are 5-O or smaller in diameter for incision or laceration repair and is designed to save time during wound repair.
Generally, the strength and other physical properties of the cyanoacrylate adhesives are directly linked to the length and complexity of their alkyl side chain. Short, straight-chain derivatives (ethyl or butyl cyanoacrylate) form tight and stronger bonds compared with complex or long-chain derivatives (propoxypropyl cyanoacrylate and octylcyanoacrylate) .
Octyl cyanoacrylate (OCA) when applied topically degrade slowly, forming few toxic degradation products before the polymers slough off. In theory, the longer the chain (e.g., octyl), the slower the polymer degrades and thus the less probability of cytotoxicity or histotoxicity as the chain length increases.
The heat released during the polymerization of OCA is less as compared to that of BCA because of OCA’s slower rate of polymerization. While a polymer film of OCA is stronger and more flexible, OCA’s setting time is longer than BCA’s in general .
SurgiSeal was developed with the goal to improve and enhance 2-OCA’s characteristics as a tissue adhesive. Even though the active ingredient of both SurgiSeal and the leading competitor is 2-OCA, SurgiSeal integrates many innovations in formulation, manufacturing process and applicator design which makes the product stand out in terms of benefits and convenience.
SurgiSeal consists of more than 98% 2-OCA with a trace amount of polymerization accelerator. The 2-OCA is stabilized with a free radical inhibitor and an anionic inhibitor. For visual detection, a trace quantity of the colorant is also included. SurgiSeal is packaged in a user-friendly and single use plastic applicator containing 0.35mL of adhesive. SurgiSeal is sterilized inside the final packaging by a certified sterilization method. The plastic applicator seal is connected to a piece of sponge, allowing the adhesive to be easily dispensed onto the sponge once the sponge connection is folded. A uniform sealing film is formed by applying the adhesive-saturated sponge tip on the wound.
In addition to the chemical, physical and mechanical properties, another practical aspect of cyanoacrylate adhesive is ease of use, which is often related to the applicator design of the adhesive .
SurgiSeal has been evaluated for key adhesive properties, such as tensile strength, overlap shear strength, peel adhesive strength and impact strength. The leading competitor also has been evaluated for the same. All the tests were conducted according to the standard methods of ASTM (American Society for Testing and Materials).
SurgiSeal demonstrated strong adhesive strength in all testing. SurgiSeal is significantly stronger in the test of T-Peel loading and is comparable in the tests of Tensile loading, Lap shear tensile loading and Wound closure strength.
Flexibility was also tested using the mandrel bend technique according to ASTM D4338-97. Both SurgiSeal and the leading competitor passed the test and showed no signs of cracks, blistering, blushing, fractures or flaking.
To assess the efficacy of SurgiSeal for the application of incision wound closure, in vivo biomechanical evaluation was performed using the rat linear incision wound model. The average ultimate pressures applied at the wound site for SurgiSeal and the leading competitor were the same, indicating that SurgiSeal possesses bonding strength comparable to the leading competitor’s.
Setting time is also positively correlated to polymerization rate. In general, as per earlier discussion, OCA has a slower polymerization rate as compared to BCA and thus has a longer setting time. To achieve a shorter setting time, a trace amount of an accelerator is added in the formulation of SurgiSeal . The setting time of SurgiSeal is slightly shorter than that of the leading competitor.
Applicator dispensing width is defined as the dispensed adhesive width of an individual stroke of an applicator, and the surface coverage area is measured by the applicator dispensing width and length. Both SurgiSeal and the leading competitor were tested on pig skin. The average dispensing width of SurgiSeal was 17.6mm, compared to the 7.7mm average dispensing width of the leading competitor. The average surface coverages of SurgiSeal and the leading competitor were 27.9 and 11.5 inch2, respectively. The tests demonstrate that SurgiSeal can provide much larger and wider coverage per applicator compared to the leading competitor .
Adhesives with a high Moisture Vapor Transmission Rate (MVTR) improve wound care . For these tests, MVTR was determined using a Mocon Permatran-W101 Water Vapor Permeability Instrument in accordance with ASTM D-6701. SurgiSeal and the leading competitor were applied and cured on a 2” square collagen film. MVTRs for SurgiSeal and the leading competitor were 2180 and 918 g/m2/day, respectively. SurgiSeal film is more vapor permeable than the leading competitor’s film, which should contribute to better and rapid wound healing.
The leading competitor’s product is stored in a glass vial that is crushed prior to application. The vial is then squeezed to apply the adhesive smoothly while avoiding dripping of the adhesive. A SurgiSeal applicator can be opened by simply folding the sponge connection thus it is more convenient to use .
According to the Instruction for Use, the leading competitor requires at least three layers of application . SurgiSeal requires at least two layers of applications on a wound incision. The second layer can be applied after the first layer dries, usually after 30 seconds.
SurgiSeal has a shorter setting time, a wider dispensing width and a larger coverage area, giving it faster wound sealing than the leading competitor .
Figure 1: unique product features of SurgiSeal
Cyanoacrylate tissue adhesives have been studied extensively compared with sutures and other wound closure agents for topical wound closure and have consistently been shown to produce cosmetic results while improving the speed of closure and being overall less painful .
SurgiSeal being a topical skin adhesive has a wide application on various types of surface wounds. It can be effectively used for repairing laceration wound and superficial incision closures.
Lacerations are the wounds seen as a cut on the skin with a blunt, linear or irregular edges. These can be minor or can run upto deep dermal layers. The tension lines across the wound site makes the edges to spread and difficult to heal. Therefore, for proper healing the edges need to come into the close proximity leading to successful wound closure.
SurgiSeal being tissue adhesive in nature helps in keeps the wound edges in place relieving the tension across the wound site. This leads to faster healing, reducing extent of unpleasant scar formation and getting the desired cosmetic outcome. However, the deep dermal wounds require buried suturing to reduce tensile shear forces which may cause premature sloughing. Moreover, the SurgiSeal has smooth covering over the wound with wide area coverage forming the waterproof sealing and providing the antimicrobial barrier .
Proper wound preparation involves evaluating the patient and the wound for factors that may have an impact on wound healing and the eventual cosmetic outcome. The appropriate use of anesthetics, irrigation, and debridement as well as the method of wound repair can be determined from this evaluation .
For the superficial incision closures and repairing laceration wound, apply SurgiSeal as follows:
Figure 2: Method of application for SurgiSeal
Complications and poor outcomes with the use of tissue adhesive can be avoided by selecting the proper wounds for closure with adhesives, using dermal sutures where appropriate, and following the proper application techniques. Beside these there are following points to be noted during application :
Octyl-cyanoacrylate topical skin adhesive has high tensile strength, it holds the wound edges together and provide microbial protection until the wound heals naturally. The adhesive remains in place for 5-10 days before naturally sloughing off the skin. Keep wounds clean because they are prone to infection for the first 24 to 48 hours after repair .
While the wound is healing, aftercare of the wound should be taken properly, as follows:
Skin and tissue around the wound are sensitive any additional injury in this region leads to more damage. Earlier techniques of wound closure, like suturing and stapling, provides the wound closure but additionally leads the puncturing of the healthy tissues around the wound and also may lead to relocation of microbes on the surface to enter inside the skin. Furthermore, the puncturing of tissues may lead to additional marks and unwanted scar formation. Altogether, these techniques are painful and needs precise expertise to carry out the procedure.
SurgiSeal a topical skin adhesive holds the wound edges together and helps in natural healing of the wound. It also forms the waterproof layer and microbial barrier keeping the infections at check. Its application is painless, easy to learn and can effortlessly be incorporated into physicians practice. The high tensile strength of octyl-cyanoacrylate provides flexibility and freedom to move around. The formula leads to the minimum scar formation and the desired cosmetic results.