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History and
development:
In 1959, a variety
of cyanoacrylate adhesives were developed, some types of which are
now used for surgical purposes in Canada and Europe. These glues
polymerize on contact with basic substances such as water or blood
to form a strong bond. The first glue developed was methyl
cyanoacrylate, which was studied extensively for its potential
medical applications and was rejected due to its potential tissue
toxicity such as inflammation or local foreign body reactions.
Methyl alcohol has a short molecular chain which contributes to
these complications.
Further research
revealed that by changing the type of alcohol in the compound to
one with a longer molecular chain, the tissue toxicity was much
reduced. All the medical grade tissue adhesives currently
available for human use contain butyl-esters, which are costlier
to produce.
In 1964, the
Tennessee Eastman lab submitted its first application for new drug
approval to the FDA. The military learned of this new glue and
became extremely interested in its potential for use in field
hospitals. MASH units in Vietnam were overloaded. Many solders
were dying from chest and abdominal wounds, despite the best
efforts of medics. In 1966 a special surgical team was flown to
Vietnam, trained and equipped to use cyanoacrylate adhesive. A
quick spray over the wounds stopped bleeding and bought time until
conventional surgery could be performed. The possibilities were
immediately seized by the medical communities of Europe and the
Far East. Meanwhile the FDA changed standards and kept requesting
additional data until Eastman was reluctantly forced to withdraw
his application. (Jueneman, 1981)
Histoacryl Blue
(n-butyl cyanoacrylate) has been used extensively in Europe since
the 1970s for a variety of surgical applications including middle
ear surgery, bone and cartilage grafts, repair of cerebrospinal
fluid leaks, and skin closure. It has been available in Canada
through Davis & Geck Canada, with no adverse effects reported
to date. Further, laboratory studies have been done which
concluded that it has no carcinogenic potential. Tissue toxicity
has only been noted when the adhesive is introduced deep in highly
vascular areas (the perineum qualifies). While I always take
claims of harmlessness with a grain of salt, if used as directed,
these adhesives appear to be basically safe.
(Quinn &
Kissick, 1994) Current use: Although not labeled as such,
over-the-counter Super Glue products contain methyl alcohol,
because it is inexpensive to produce. Cyanoacrylates cure by a
chemical reaction called polymerization, which produces heat.
Methyl alcohol has a pronounced heating action when it contacts
tissue and may even produce burns if the glue contacts a large
enough area of tissue. Rapid curing may also lead to tissue
necrosis. Midwives have not noted such reactions because minimal
amounts are being used for perineal repair. Nevertheless, with a
greater toxic potential, over-the-counter products are
inappropriate for use in wound closure. (Quinn & Kissick,
1994)
Medical grade
products currently available contain either butyl, isobutyl or
octyl esters. They are bacteriostatic and painless to apply when
used as directed, produce minimal thermal reaction when applied to
dry skin and break down harmlessly in tissue. They are essentially
inert once dry. Butyl products are rigid when dry, but provide a
strong bond. Available octyl products are more flexible when dry,
but produce a weaker bond.
When used for
repair, ideally the wound to be closed is fresh, clean, fairly
shallow, with straight edges that lie together on their own. The
glue is applied to bridge over the closed edges; it should not be
used within the wound (on raw surfaces), where it will impair
epithelization. The only currently FDA approved adhesives suitable
for use as suture alternatives are veterinary products; n-butyl-
cyanoacrylate tissue adhesives Vetbond (3M) and Nexaband liquid
and octyl-based Nexaband S/C (intended for topical skin closure
when deep sutures have been placed). Histoacryl Blue (butyl based)
(Davis & Geck) and Tissu-Glu (isobutyl based) (Medi-West
Pharmaceuticals) are sold in Canada for human use. DMSO (dimethyl
sulfoxide) or acetone serve as removers. (Helmstetter, 1995; Quinn
& Kissick, 1994)
How to use
tissue adhesive:
Although not
specifically recommended for perineal repair, tissue adhesive has
been successfully used by some midwives. However, Hisotcryl Blue
was used in place of interrupted or subcuticular stitches in a
small study of the closure of the superficial layer in
mediolaterial clitorotomy (episiotomy). (Adoni & Anteby) In
this study, the yoni (vaginal) mucosa and subcutaneous layers were
closed with conventional suture techniques. It might be a good
alternative to offer when women refuse conventional sutures.
Tissue adhesive works best when the wound is moderately shallow.
Midwives report that extremely shallow wounds tend to pull apart
as healing occurs and usually require no closure of any kind. The
wound should also have no pockets to collect lochia and should not
require other sutures. However, as the study mentioned above
demonstrates, it can also be used instead of subcuticular sutures
after placing basting stitches.
Tissue glue is only
applied to outside surfaces to bridge over edges; do not apply it
directly to raw surfaces. The wound edges should be straight and
lie together naturally. Insert a tampon, then clean and dry the
skin thoroughly. Have your assistant stabilize the wound edges
from top to bottom (be sure the edges are matched correctly).
Insert your finger between the edges and pull it out to bring them
forward slightly. This is to ensure that the wound edges are not
rolled inward toward each other, but meet perfectly. It could also
be accomplished with a tissue forceps. Hold gauze against the area
immediately below the apex to catch and drips as you apply the
glue. Apply tiny dots of glue sparingly at intervals where the
wound edges meet. Or, apply a bead of tiny droplets to bridge the
edges. (Thick applications do not enhance bonding and tend to
crack and loosen prematurely.) Products dyed blue are easier to
see. (If using Histoacryl Blue, attach a 27 g. syringe needle to
the ampoule hub to help control application.
After use, the
needle should be discarded and replaced with a new needle that
does not have glue within its lumen.) Be careful to apply the glue
on where it is needed; glue removers should not the used in the
genital area. As long as no part of the tube tip or the attached
needle contacts the tissue or bodily fluids, the tube can be
reused.
Use a hair dryer or
fan the area dry, which takes about 30 seconds. Adhesive will
stiffen when dry. Women should observe the same precautions as
those who have refused sutures entirely. Bathing is not
contraindicated but prolonged soaking should be avoided. Expect
the adhesive to flake off in 3 to 7 days. Allergic reactions are
very rare, but may include inflammation and swelling.
References
(Various midwives
1993-95)
Adoni, A., &
Anteby, E., "The Use of Histoacryl for Episiotomy
Repair," Br. J. of Ob Gyn, Vol. 98, May 1991, pp. 476-8.
Heimstetter, G., personal communciation, Permabond Internat.
Bridgewater, NJ, 1995.
Jueneman, F,
"Stick it to um," Industrial Research & Dev. Aug.
1981, p. 19.
Quinn, J., &
Kissack, J., "Tissue Adhesives for Laceration Repair During
Sporting Events," Clinical J. of Sports Med., Vol. 4 No. 4,
1994, p. 245.
Sources of
tissue adhesives:
Animal Care
Products, 3M Health Care, 3M Center Building 225 1N 07, St. Paul,
MN 55144-1000, (612) 733-8477. 3M produces Vetbond Tissue
Adhesive.
Veterinary Products
Laboratory (800) 548- 2828 distributes Nexaband products which are
manufactured by Tri-Point in Raleigh, NC (919) 790-1041. These
products are restricted items sold and approved for veterinary use
only.
Davis & Geck-CANADA
(905) 470-3647 distributes Histoacryl Blue, which is manufactured
in Germany by B. Braun.
Medi-West
Pharmaceuticals markets Tissu-Glu.
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