(a) Plain catgut. Plain catgut holds tensile strength for about seven
days. Sheep's intestine is the source of plain suture. This suture is used in tissue
where rapid healing is expected to occur such as subcutaneous tissue and for tying
superficial blood vessels. Plain catgut suture is pale yellow in color. A disadvantage of
this type of suture is that it increases the formation of pus and has high tissue reactivity.
(b) Chromic catgut. Chromic suture has been treated with chromic
oxide so that it will resist digestion or absorption for longer periods of time. Chromic
suture has the same source as plain suture. Chromic suture is used in tissue where
rapid healing is not expected to take place, such as muscle fascia, peritoneum, and
body organs. The advantage of this type of suture is that it retains its tensile strength
for about two to three weeks. As with plain catgut, chromic suture increases the
formation of pus and has high tissue reactivity.
(c) Synthetic absorbable suture. Dexon and Vyeril are examples of
synthetic absorbable suture. Advantages include that it retains tensile strength for sixty
days or more. Also, there is low tissue reactivity and lower pus formation than with the
use of plain or chromic cat gut. A disadvantage is that this type of suture material does
not glide through tissue easily. Snags tend to occur, making knot tying more tedious.
(5) Skin tapes. Steri-Strips, clearon, and skin-strips are examples of skin
tapes. Skin tapes are often used in place of sutures to repair surface lacerations.
Advantages of skin tapes are the low incidence of infection and no suture marks. Also,
the patient need not return to have sutures removed. Disadvantages are that skin tapes
are not practical in body areas that may become wet or that have motion. Young
children have a tendency to pull off skin tapes. Also, at times wound edges invert after
a skin tape has been applied.
2-6.
BASIC LACERATION REPAIR
a. Categories of Wound Closure. Closure of wounds is divided into three
major categories: closure by primary intent, closure by secondary intent, and closure by
tertiary intent.
(1) Closure by primary intent. A wound that is repaired without delay after
the injury is the definition of wound closure by primary intent. Such closure prevents the
formation of granulation tissue and yields the fastest healing with the best cosmetic
result. Closure by primary intent is the treatment of choice for a wound that is not
infected or grossly contaminated. Closing the wound soon after the injury is important.
The longer the time between injury and wound closure, the more bacteria can multiply.
Most lacerations should be closed within eight hours from the time of injury. If the
patient is debilitated, has poor circulation, laceration caused by crushing injuries, or is
grossly contaminated, wound closure should be performed within four hours.
MD0574
2-10