4-9 WOUND CLOSURE
LEARNING OBJECTIVE: Recognize the different types of suture material and
their uses; recall topical, local infiltration and nerve-block anesthetic
administration procedures; and identify the steps in wound suturing and suture
The care of the wound is largely controlled by the tactical situation,
facilities available, and the length of time before proper medical care may be
available. Normally, the advice to the medical technician regarding the suturing of wounds
is DO NOT ATTEMPT IT. However, if days are expected to elapse before the patient
can be seen by a surgeon, the medical technician should know how to use the various suture
procedures and materials, and how to select the most appropriate of both.
Before discussing the methods of coaptation (bringing together), some of the
contraindications to wound closing should be described.
- If there is reddening and edema of the wound margins, infection manifested
by the discharge of pus, and persistent fever or toxemia, DO NOT CLOSE THE WOUND.
If these signs are minimal, the wound should be allowed to “clean up.” The
process may be hastened by warm, moist dressings, and irrigations with sterile
saline. These aid in the liquefaction of necrotic wound materials and the
removal of thick exudates and dead tissues.
- If the wound is a puncture wound, a large gaping wound of the soft tissue,
or an animal bite, leave it unsutured. Even under the care of a surgeon, it is
the rule not to close wounds ofthis nature until after the fourth day. This is
called “delayed primary closure” and is performed upon the indication of a
healthy appearance of the wound. Healthy muscle tissue that is viable is evident
by its color, consistency, blood supply, and contractibility. Muscle that is
dead or dying is comparatively dark and mushy; it does not contract when pinched, nor does it bleed when cut. If this type of tissue is
evident, do not close the wound.
- If the wound is deep, consider the support of the surrounding tissue; if
there is not enough support to bring the deep fascia together, do not suture
because dead (hollow) spaces will be created. In this generally gaping type of
wound, muscles, tendons, and nerves are usually involved. Only a surgeon should
attempt to close this type of wound.
To a certain extent, firm pressure dressings and
immobilization can obliterate hollow spaces. If tendons and nerves
do not seem to be involved, absorbable sutures may be placed in the
muscle. Be careful to suture muscle fibers end-to-end and to
correctly appose them. Close the wound in layers. This is extremely
delicate surgery, and the medical technician should weigh carefully
the advisability of attempting it–and then only if he has observed
and assisted in numerous surgical operations.
- If the wound is small, clean, and free from foreign bodies and signs of
infection, steps should be taken to close it. All instruments should be checked,
cleaned, and thoroughly sterilized. Use a good light and position the patient on
the table so that access to the wound will be unhampered.
The area around the wound should be cleansed and then prepared with an
antiseptic. The wound area should be draped, whenever possible, to maintain a
sterile field in which the medical technician will work. The medical technician should wear a cap
and mask, scrub his hands and forearms, and wear sterile gloves.
In modern surgery, many kinds of ligature and suture materials are used. All
can be grouped into two classes: non-absorbable sutures and absorbable sutures.
NONABSORBABLE SUTURES.—These are sutures that cannot be absorbed by the body
cells and fluids in which they are embedded during the healing process. When
used as buried sutures, these sutures become surrounded or encapsulated in
fibrous tissue and remain as innocuous foreign bodies. When used as skin
sutures, they are removed after the skin has healed. The most commonly used
sutures of this type and the characteristics associated with each are listed
- Silkfrequently reacts with tissue and can be “spit” from the wound.
- Cotton—loses tensile strength with each autoclaving.
- Linen—is better than silk or cotton but is more expensive and not as
- Synthetic materials (e.g., nylon, dermalon) are excellent, particularly
for surface use. They cause very little tissue reaction. Their only problem
seems to be the tendency for the knots to come untied. (Because of this
tendency, most surgeons tie 3 to 4 square knots in each such suture.) Nylon is
preferred over silk for face and lip areas because silk too often causes tissue
- Rust-proof metal (usually stainless steel wire) has the least tissue
reaction of all suture materials and is by far the strongest. The primary
problems associated with it are that it is more difficult to use because it
kinks and that it must be cut with wire cutters.
ABSORBABLE SUTURES.—These are sutures that are absorbed or digested during
and after the healing processes by the body cells and tissue fluids in which
they are embedded. It is this characteristic that enhances their use beneath the
skin surfaces and on mucous membranes.
Surgical gut fulfills the requirements for the perfect suture
— ease of
manufacture, tensile strength, and variety available
— more often than any other
- Manufacture of catgut: Though it is referred to as “catgut,” surgical gut
is derived from the submucosal connective tissue of the first one-third (about 8
yards) of the small intestine of healthy government-inspected sheep. The
intestine of the sheep has certain characteristics that make it especially
adaptable for surgical use. Among these characteristics is its uniformly
fine-grained tissue structure and its great tensile strength and elasticity.
- Tensile strength of catgut: This suture material is available in sizes of
6-0 to0 and 1to 4, with 6-0 being the smallest diameter and 4 being the largest.
The tensile strength increases with the diameter of the suture.
- Varieties of catgut: Surgical gut varies from plain catgut (the raw gut
that has been gauzed, polished, sterilized, and packaged) to chromic catgut
(that has undergone various intensities of tanning with one of the salts of
chromic acid to delay tissue absorption time). Some examples of these variations
and their absorption times follow in table 4−3.
Table 4-3.—Absorption Times of Various Types of Surgical
|B: Mild chromic
|C: Medium chromic
|D: Extra chromic
Suture needles may be straight or curved, and they may have either a tapered
round point or a cutting edge point. They vary in length, curvature, and
diameter for various types of suturing. Specific characteristics of suture
needles are listed below.
- Size: Suture needles are sized by diameter and are available in many sizes.
- Taper point: Most often used in deep tissues, this type needle causes
minimal amounts of tissue damage.
- Cutting edge point: This type needle is preferred for suturing the skin
because of the needle's ability to penetrate the skin's toughness.
- Atraumatic (atraloc, wedged): These needles may either have a cutting edge
or a taper point. Additionally, the suture may be fixed on the end of the needle
by the manufacturer to cause the least tissue trauma.
Preparation of Casualty
Before suturing the wound(s) of any victim, the following steps should be
taken to prepare the casualty.
- Examine the casualty carefully to determine what materials are needed to
properly close the wound.
- Select and prepare sterile instruments, needles, and suture materials.
- Position the patient securely so that access to the wound and suture tray
is optimal. It is usually not necessary to restrain patients for suturing.
- Make sure a good light is available.
- Strictly observe aseptic wound preparation. Use mask, cap, and gloves.
Thorough cleaning and proper draping are essential.
- Select an anesthetic with care. Consider the patient’s tolerance to pain,
time of injury, medications the patient is taking or has been given, and the
possible distortion of the tissue when the anesthetic are infiltrated.
SELECTION OF ANESTHESIA.—The most common local anesthetic used is Xylocaine®,
which comes in various strengths (0.5%, 1%, 2%) and with or without epinephrine.
Injectables containing epinephrine must never be used on the fingers, toes,
ears, nose – any appendage with small vessels – because of the vasoconstricting
effect of the epinephrine. Epinephrine is also contraindicated in patients with
hypertension, diabetes, or heart disease.
The three methods of anesthestia administration are topical, local
infiltration, and nerve block. Topical anesthetics are generally reserved for
ophthalmic or plastic surgery, and nerve blocks are generally accomplished by an
anesthesiologist or anesthetist for the surgical patient. For a medical
topical anesthesia is limited to the instillation of eye drops for mild corneal
abrasions after all foreign bodies have been removed. DO NOT attempt to remove
embedded foreign bodies. Nerve blocks are limited to digital blocks wherein the
nerve trunks that enervate the fingers or toes are anesthetized. The most common
method of anesthesia used by a medical technician is the infiltration of the anesthetizing
agent around a wound or minor surgical site.
ADMINISTRATION OF ANESTHESIA.— Performing a digital block is a fairly simple
procedure, but it should not be attempted except under the supervision of a
physician or after a great deal of practice. The first step is cleansing
the injection site with an antiseptic solution. The anesthetizing agent is then
infiltrated into the lateral and medial aspects at the base of the digit with a
small bore needle (25- or 26-gauge), taking care not to inject into the veins or
arteries. Proper placement of the anesthesia should result in a loss of
sensitivity in a few minutes. This is tested by asking the patient if he can
distinguish a sharp sensation or pain when a sharp object is gently applied to the skin.
Administering local anesthesia is similar except you are anesthetizing nerves
immediately adjacent to where you will be working instead of nerve trunks. There
are two generally accepted methods of infiltrating the anesthesia. One is
through the skin surrounding the margin of the wound and the other is through
the wound into the surrounding tissue. In either case, sufficient quantities
must be infiltrated to effect anesthesia approximately 1/2 inch around the
wound, taking care not to inject into a vein or artery.
The maximum recommended amount of Xylocaine to be used is 50 cc for
a 1% solution or the equivalent.
General Principles of Wound Suturing
Wounds are closed either primarily or secondarily. A primary closure takes
place within a short time of when the wound occurs, and it requires minimal
cleaning andpreparation. A secondary closure, on the other hand, occurs when
there is a delay of the closure for up to several days after the wound's
occurrence. A secondary closure requires a more complex procedure. Wounds 6 to
14 hours old may be closed primarily if they are not grossly contaminated and
are meticulously cleaned. Wounds 14 to 24 hours old should not be closed
primarily. When reddening and edema of the wound margins, discharge of pus,
persistent fever, or toxemia are present, do not close the wound.
Do not use a primary closure for a large, gaping, soft-tissue wound. This
type of wound will require warm dressings and irrigations, along with aseptic
care for 3 to 7 days to clear up the wound. Then a secondary wound closure may
The steps to perform a delayed wound closure are outlined below.
- Debride the wound area and convert circular wounds to elliptical ones
before suturing. Circular wounds cannot be closed with satisfactory cosmetic
- Try to convert a jagged laceration to one with smooth edges before
suturing it. Make sure that not too much skin is trimmed off; that would make
the wound difficult to approximate.
- Use the correct technique for placing sutures. The needle holder is
applied at approximately one-quarter of the distance from the blunt end of the
needle. Suturing with a curved needle is done toward the person doing the suturing. Insert the needle into the skin at
a 90° angle, and sweep it through in an arclike motion, following the general
arc of the needle.
- Carefully avoid bruising the skin edges being sutured. Use Adson forceps
and very lightly grasp the skin edges. It is improper to use dressing forceps
while suturing. Since there are no teeth on the grasping edges of the dressing
forceps, the force required to hold the skin firmly may be enough to cause
- Do not put sutures in too tightly. Gentle approximation of the skin is
all that is necessary. Remember that postoperative edema will occur in and about
the wound, making sutures tighter. Figure 4-33 illustrates proper wound-closure
- If there is a significant chance that the sutured wound may become
infected (e.g., bites, delayed closure, gross contamination), place an iodoform
(anti-infective) in the wound. Or place a small rubber drain in the wound, and
remove the drain in 48 hours.
- When suturing, the best cosmetic effect is obtained by using numerous
interrupted simple sutures placed 1/8 inch apart. Where cosmetic result is not a
consideration, sutures may be slightly farther apart. Generally, the distance of
the needle bite from the wound edges should be equal to the distance between
- When subcutaneous sutures are needed, it is proper to use 4-0 chromic
- When deciding the type of material to use on skin, use the finest diameter
that will satisfactorily hold the tissues. Table 4-4 provides guidance as to
the best suture to use in selected circumstances.
Table 4-4.—Suture Guide
|Children under 3 years
|All other faces
|Feet, elbows, knees
||#34 or #36 wire, or 4-0
||6-0 or 5-0
- When cutting sutures, subcutaneous catgut should have a 1/16-inch tail.
Silk skin sutures should be cut as short as is practical for removal on the face
and lip. Elsewhere, skin sutures may have longer tails for convenience. A tail
over 1/4 inch is unnecessary, however, and tends to collect exudate.
- The following general rules can be used in deciding when to remove
- Face: As a general rule, 4 or 5 days. Better cosmetic results are obtained
by removing every other suture and any suture with redness around it on the third day and the remainder
on the fifth day.
Body and scalp: 7 days.
Soles, palms, back, or over joints: 10 days, unless excess tissue
reaction is apparent around the suture, in which case they should come
Any suture with pus or infection around it should be removed
immediately, since the suture's presence will make the infection worse.
When wire is used, it maybe left in safely for 10to 14 days.
Many kinds of accidents cause injuries to bones, joints, or muscles. In
giving first aid or emergency treatment to an injured person, you must always
look for signs of fractures (broken bones), dislocations, sprains, strains, and
An essential part of the emergency treatment for fractures consists of
immobilizing the injured part with splints so that the sharp ends of broken
bones will not move around and cause further damage to nerves, blood vessels, or
vital organs. Splints are also used to immobilize severely injured joints or
muscles and to prevent the enlargement of extensive wounds. You must have a
general understanding of the use of splints before going on to learn the
detailed first aid treatment for injuries to bones, joints, and muscles.