suturing Flashcards
made of materials that are not
readily broken down by the
body’s enzymes or by
hydrolysis
non absorbable sutures
Absorbable Suture is broken
down by one of two methods
1. Enzymatic breakdown of
organic material
Plain or Chromatic
2. Hydrolysis
Vicryl
consists of processed collagen derived from
the submucosa of animal intestines
cat gut (absorbable)
broken down enzymatically after about 7
days
plain gut (absorbable)
collagen treated with chromium salts
to delay break down
typically loses its strength after 2-3
weeks is completely digested after about 3 months
chromic gut (absorbable)
(e.g., Vicryl and Monocryl). These materials
are broken down non-enzymatically by hydrolysis;
water penetrates the suture filaments and causes
breakdown of the polymer chain.
As a result, synthetic absorbable sutures tend to
evoke less tissue reaction than plain or chromic gut
polymers (absorbable)
retains 75% of its original tensile
strength at 2 weeks and retains 50% at 3
weeks
vicryl
retains 60-70% of its strength at 1
week and 30-40% at 2 weeks
monocryl
soft, pliable
monofilament material that retains about 50%
of its strength at 4 weeks after implantation
PDS II (p-dioxanone)
Synthetic non-absorbable materials
Nylon, Prolene, and Mersilene
There are naturally occurring non-absorbable materials
silk and cotton
single smooth strand
they glide through tissues with less
friction
may be associated with lower rates of
infection
one generally ties knots with 5 or 6
“throws”
monofilament
The bigger the suture material,
the bigger the needle
multiple fibers woven together
less likely to slip
3 throws with silk or Mersilene
multifilament
Taper to the point, and a cross-section anywhere along the shaft would reveal a round shaft
used for tissue that is easy to penetrate, such as bowel or blood
vessels.
Causes excess trauma to the skin because of difficulty in penetration and the need to grasp the skin edge very tightly with forceps.
taper needles
the bigger the number
the smaller the size of the suture
Most sutures come as a single piece, with
the suture material swaged onto the base of
the needle.
Taper or “smooth”
Cutting
similar to a
conventional cutting needle, except
that the cutting edge faces down
instead of up. This may decrease
the likelihood of sutures pulling
through tissue in some cases
revers cutting needle
Triangular in shape, and the apex
forms a cutting surface, which
facilitates penetration of tough
tissue, such as skin. make it much easier to penetrate tough tissue.
cutting needle
how should you grab the needle
The needle should be grasped in the
tip of the needle holder about 2/3 of
the way back from the point.
Grasping further back at the swaged
end tends to weaken the needle and
its attachment to the suture, and you
are likely to bend the needle.
The forceps should be held so one arm is an
extension of thumb and the other is an extension of
your index finger
The base of the forceps should rest on the dorsal
surface of the web space between the thumb and
index finger
The forceps allow you to create counter traction and
control the position of the skin edge to facilitate
passage of the needle perpendicularly through the
skin
The forceps should also be used to grasp the
needle when repositioning it in the needle holder
forceps
The ideal skin suture should form a
right angle (rectangle)
The most common method is to place the
thumb and ring finger slightly into the
instrument’s rings.
This allows you to pronate and supinate and to
open and close the jaws of the needle holder.
Avoid inserting your fingers far into the rings of
the instrument, since this will tie up your fingers
and impede your mobility.
Some surgeons do not put their fingers into the
rings at all and simply grasp the rings and body
of the needle holder in the palm of their hand.
needle holder
generally held with the
thumb slightly in one ring and the ring
finger in the other. The index finger
stabilizes the instrument by resting on
the shaft.
When cutting sutures, some
recommend sliding the tips of the
scissors down the strands to the point
where they will be cut, but it probably
makes more sense to simply move the
tips of the scissors directed to the point
where the cut will be made.
For external non-absorbable sutures it
is important to leave 4-5 mm “ears” to
facilitate suture removal
scissors
For most areas of the body, except the face the
sutures should be placed in the skin
3–4 mm from
the wound edge and 5–10 mm apart
knots
Square knot
Surgeon knot
- Start from the outside of the skin, go
through the epidermis into the
subcutaneous tissue from one side, then
enter the subcutaneous tissue on the
opposite side, and come out the epidermis
above. - To evert the edges, the needle tip
should enter at a 90° angle to the skin.
Then turn your wrist to get the needle
through the tissues. - You can use simple sutures for a
continuous or interrupted closure.
simple sutures
Sutures placed on the face should be
approximately
2–3 mm from the skin edge and 3–
5 mm apart
To ensure proper apposition of the
wound without excess tissue on one
side (also called a “dog ear”), the
clinician places the first stitch at the
midline of the wound
The next two stitches go on each side of
the first stitch, midway between the
center stitch and the wound corners.
Additional bisecting stitches are placed
until the wound is properly aligned
placement
place the sutures again and again without
tying each individual suture
If the wound is very clean and it is easy to bring the edges together, a
continuous closure is adequate and quicker to perform
Continuous closure is the technique of choice to help stop bleeding from
the skin edges, which is important, for example, in a scalp laceration
continuous suture
individually placed
Technique of choice if you are worried about the cleanliness of the wound
If the wound looks like it is becoming infected, a few sutures can be
removed easily without disrupting the entire closure
Interrupted sutures can be used in all areas but may take longer to place
than a continuous suture
interrupted sutures
(A) The closure is started with the standard
technique of a percutaneous simple interrupted
suture, but the suture is not cut after the initial
knot is tied.
(B and C) The needle is then used to make
repeated bites, starting at the original knot by
making each new bite through the skin at an
angle of 45 degrees to the wound orientation.
(D) The cross stays on the surface of the skin
will be at an angle of 90 degrees to the wound.
(E and F) The final bite is made at an angle of
90 degrees to the wound orientation to bring the
suture out next to the previous bite. The final
bite is left in a loose loop, which acts as a free
end for tying the knot.
running
good choice when the
skin edges are difficult to evert.
Sometimes you may want to close a wound
with a few scattered mattress sutures and
place simple sutures between them.
More technically challenging to place
mattress sutures, but it is often worth the
effort because good dermis-to-dermis contact
is achieved
mattress sutures
useful for bringing together underlying tissues such as
blood vessels, muscle, fascia, or extensor tendons. It is not commonly
used for skin closure.
Usually a tapered needle and absorbable sutures are used.
figure of 8 sutures
vertical
in a line, far far, near, near
horizontal
box
- Start on the side opposite from you. Go through the full thickness of
tissues on that side, then finish the first half of the stitch by going from
bottom to top on the opposite side. Advance just a little farther (1.0–1.5 cm)
along the tissue. The needle should now be back on top of the tissue. - Now enter the first side (going from top to bottom) just across from the
suture on the other side. Go through the full thickness of the tissue and
come out on the undersurface of the tissue. - Now enter the undersurface of the other side even with the first suture
and come out on top
figure of 8 sutures
This technique is useful for wide, gaping wounds and when it is difficult to
evert the skin edges. When buried intradermal sutures are placed properly,
they make skin closure much easier. The purpose of this stitch is to line up
the dermis and thus enhance healing. The knot needs to be as deep into the
tissues as possible (hence the term buried) so that it does not come up
through the epidermis and cause irritation and pain.
1. Use a cutting needle and absorbable material.
2. Start just under the dermal layer and come out below the epidermis. You
are going from deep to more superficial tissues. The vertical mattress
suture.
3. Now the technique becomes a bit challenging. You need to enter the skin
on the opposite side at a depth similar to where you exited the skin on the
first side, just below the epidermis. To do so, you should position the needle
with the tip pointing down and pronate your wrist to get the correct angle. It
will help to use the forceps (in the other hand) to hold up the skin. The
needle should come out of the tissues below the dermis. Try to get as little
fat in the stitch as possible; it does not contribute to the suture.
4. Tie the suture
buried intradermal sutures
- Place your needle holder in the center between the skin edges parallel
to the wound. One end of the suture should be on each side of the
wound without crossing in the middle. - Wrap the suture that is attached to the needle once or twice around the
needle holder in a clockwise direction. - Grab the short end of the suture with the needle holder.
- Pull it through the loops, and have the knot lie flat. The short end of the
stitch should now be on the opposite side. - Let go of the short end.
- Bring the needle holder back to the center, parallel to the wound
edges. - Repeat steps 4–6 at least one or two times more.
- Cut the suture ends about 1 cm from the knot.
instrument tie
The main advantage of staples over sutures is
that they can be placed
quickly. Speed may be an important advantage when you need to close a
bleeding wound quickly (e.g., on the scalp) to decrease blood loss. Staples
tend to leave more noticeable marks in the skin compared with sutures.
They should not be used on the face
- The edges must be everted.
Assistant must help by using forceps to hold the skin edges so that the dermis on each side
touches. - Place the center of the stapler (usually an arrow on the stapler marks
the center) at the point where the skin edges come together. - Gently touch the stapler to the skin; you do not have to push it into the
skin. Then grasp the handle to compress it; the compression releases the
staple. Suturing: The 4. Release the handle, and move the stapler a few
millimeters back to separate the staple from the stapling device. - The staples should be placed about 1 cm apart.
stapling
