Antisepsis and Wound Care
One of the outstanding advances that medical science has made in the past hundred years is the establishment of antiseptic principles in the practice of surgery. Milestone discoveries were the germ theory by Pasteur and Koch, the emphasis on hand washing by Semmelweis, and the principles of antisepsis by Lister.
To understand the relationship between infective agents and disease has allowed the art and science of surgery to develop many new techniques, as well as life-saving procedures. Fundamentally, the principles of antisepsis deal not only with the presence or absence of germs, but also with the resistance of the person (host) to their invasion.
The acid mantle of the skin and our body’s resident normal flora constitute an important barrier to the growth of disease-producing germs. Enzymatic protection by lysozyme in the nasal secretions, tears, saliva, and other mucous membranes affords a defense of marvelous significance and complexity.
From simple wound care to most complicated surgery, every individual should know how to avoid contamination by harmful germs. During the 19th century in Austria, Doctor Semmelweis began to encourage hand washing, requiring this of his residents after each post-mortem examination and before contact with maternity patients.
The death rate from infection dropped precipitously. Although this brilliant physician was persecuted by his own profession for these “strange” doctrines, decades later he was acclaimed a medical trailblazer. Without doubt, the washing of hands is as important to safe surgery, as the use of water internally is to fighting fever.
It is especially important to know how to wash the hands and prepare them to handle diseased or injured tissues. Usually before surgery, a soft disinfected bristle brush is used to scrub the hands starting first around each finger, the ends and sides of the fingernails, the palm and backside of the hand, the wrist, and then the forearm.
To prepare for a delicate operation, ten minutes of this type of scrubbing is required, typically with an antibacterial soap. Sterile rubber or latex gloves should then be worn. Disinfectants such as organic iodine (Betadine), hexachlorophene (Phisohex), or other antibacterial soaps are used to prepare the patient’s skin for the incision.
Where this is not available, soap and water are employed, however the scrubbing must be prolonged. It is well to remember, moreover, that the mere washing of the hands with any substance does not guarantee a totally germ-free skin. Sweating is especially common under rubber or latex gloves, with the natural bacteria present in hair follicles and around the nails.
Thus the bacterial count is only transiently suppressed, while our real line of defense is our body’ s resistance. Several routines and techniques of skin preparation will be described in the accompanying table. In the treatment of skin wounds, copious irrigation with water is essential, With some force, the stream of water is directed at the contaminated areas.
The wound is thereby cleansed, allowing germs, foreign debris, and blood clots to be washed away, making the area clean for closure or suturing. Preparation of the skin with appropriate antiseptics is also helpful. Proper nutrition to the injured area includes abundant oxygen and vitamin C to aid wound healing.
Elimination of refined sugar assists in fighting infection. These measures, together with the avoidance of tobacco and other harmful substances that impair oxygen supply, will enable healing to occur rapidly.
Wound Care
There are three basic methods by which a wound heals itself. Primary Intention is the usual type of healing when an incision or laceration is closed immediately to allow close adherence of the opposing skin edges and subcutaneous layers. This permits healing from side to side with the least amount of scarring and pain.
The rate of healing of our skin depends on its blood supply and the presence or absence of pressure, tension, and infection. The facial skin, with its rich blood supply, can heal in 3-5 days, while a thickened area of skin with less nutritive potential, such as the back or feet, may require two weeks or more.
If sutures are placed, it is important to know how long healing will require to avoid too early removal and wound separation. Secondary healing of a wound occurs when the laceration is too large to be closed or is infected and must be left open. A general principle of laceration treatment is this.
A wound that has been open more than 8-12 hours is never sutured, since infection may already have developed. In such case, granulation occurs with the formation of a specialized tissue across the wound, and later coverage with new skin. Some deformity and scarring usually occurs.
Nevertheless, with the exception of very large ulcers, the skin healing is usually complete. Understandably, this takes longer. Proper care of the wound to prevent or treat infection will serve to hasten the healing process. The third method involves the initial formation of granulation tissue, then a secondary closure of the wound with sutures.
This accelerates the healing in large open lesions and is usually used when a surgical wound, for some reason, separates and must be closed again. Even more scarring takes place as a rule, but the healing is usually complete. Some essential factors in wound healing are the presence of adequate protein, vitamins, oxygen, and the prevention of infection.
It is generally recognized that the normal rate of healing in a perfectly healthy patient is the optimum rate that can be obtained. Wounds do not heal as well in anemic patients. With a normal complement of white blood cells the healing of a sterile wound is not impaired. However, when infection is present delayed healing does occur.
Swelling (edema), whether local or general, appears to interfere with the healing process. Older individuals take longer to heal than the young. Endocrine factors, such as the possible deficiency of thyroid or growth hormone, or adrenal dysfunction, may retard or interfere with the healing process.
Local factors are important. According to Van’t Hoff’s law, reactions occur more rapidly when the temperature is increased. Conversely, hypothermia will delay wound healing in most areas, although cold is sometimes used for pain control. The areas of the skin which have the best blood supply, such as the face and neck, normally heal the fastest.
Fat persons tend to heal more slowly, and their wounds tend to separate more often than in people of normal weight. Skin sutures are usually left in longer. Cleanly incised wounds will heal more rapidly than irregular jagged lacerations. The presence of a blood clot or hematoma may interfere with proper wound healing by preventing close contact of the walls of the wound, and thus there forms a pocket, called “dead space.”
Infected fluids, pus, and foreign bodies will all retard the healing of these wounds. It is critical to cleanse the wound of all foreign debris, irrigating it thoroughly before any suturing is attempted. Suture material is also important in the care of wounds. Although stainless steel is the least reactive, it is difficult to handle and remove.
The absorption of foreign material, such as gut, silk, cotton, and nylon will occur slowly, in the order that they are here mentioned. Newer sutures of nylon, Dacron, and Teflon last longer and cause less reaction, but are not suitable everywhere. A suture use manual may be consulted to aid in selecting appropriate materials. The suture manufacturer’s suggestion of needle size, type, and techniques should also be consulted.