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 solutions. These aid in the liquefaction of necrotic wound materials and the removal of thick exudates and dead tissues.
2. 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 of this nature until after the fourth day. This is called delayed primary closure and is performed under 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.
3. 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 (great care always being exercised to suture muscle fibers end-to-end and to correctly appose them) and the wound is closed in layers. This is extremely delicate surgery and the corpsman should exercise independent judgment on the advisability of attempting it, and then only if he or she 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 corpsman works. The corpsman should wear a cap and mask, scrub his or her 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:
1. Nonabsorbable sutures: Those that cannot be absorbed by the body cells and fluids in which they are embedded during the healing process. When used as buried sutures, they 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 of this type of sutures and facts associated with them are:
a. Silk: frequent tissue reaction or spitting of suture from the wound.
b. Cotton: loses tensile strength with each autoclaving.
c. Linen: better than silk or cotton but more expensive and not as readily available.
d. Synthetic material: there are many, such as nylon and dermalon. These 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, so most surgeons tie 3 to 4 square knots in each suture. Nylon is preferred over silk for face and lip areas because silk too often causes tissue reactions.
e. Rust-proof metal: usually stainless steel wire or tantalum. This has the least tissue reaction of all suture material and is by far the strongest. The primary problems are the need for wire cutters, and it is more difficult to use because it kinks.
2. Absorbable sutures: Those that are absorbed or digested by the body cells and tissue fluids in which they are embedded during and after the healing processes. It is this characteristic that enhances their use beneath the skin surfaces and on mucous membranes.