Open wounds can be caused by trauma, chronic disease, debilitation, and many other complex and variable causes. It is crucial for surgeons of any specialty to systematically master the principles of open wound diagnosis and treatment.
1. Factors affecting wound healing
A careful history and detailed examination will help to accurately identify the cause of the wound and its subsequent treatment, and attention must be paid to nutritional and functional status, immune status, smoking, and history of radioactive exposure. Although the circumstances of a trauma may be intricate, certain common factors influence the treatment and healing process of the vast majority of traumas, such as age, local ischemia, and infection.
1.1 Age: The ability to heal decreases with age, especially when combined with local ischemia and infection, and may be related to decreased natural protective mechanisms and reduced healing and remodeling functions.
1.2. Local ischemia: Most wounds will exhibit altered local tissue hypoxia, and this will lead to a decrease in the bactericidal capacity of white blood cells, making the wounds more susceptible to infection. Treatment principles such as debridement, pain relief, warmth, and hyperbaric oxygen all aim to improve local oxygen supply to enhance wound healing.
1.3. Infection: In the past, all wounds were considered infected, but this does not mean that all wounds must be treated with antimicrobial drugs. Bacteria in wounds can release free radicals, toxins, proteases and other substances to weaken the ability of wounds to repair. An indicator that a wound is infected is a bacterial count >100,000/g, but its clinical guidance is limited. In contrast, wound grading (sterile, contaminated, infected) based on the level of microbial contamination can help in treatment.
2. Initial examination.
A thorough history and physical examination aids treatment, and for orthopedic trauma-related wounds, appropriate disposition of the wounds should be performed even at the time of ABC resuscitation. The contents to be evaluated include: cause of injury, location, scope, complexity (involved tissues and their degree of involvement), presence of foreign bodies, contamination, blood loss (arterial/venous), motor or sensory function involvement, tissue viability, etc. X-ray examination helps to detect bone damage or potential foreign bodies.
3. Initial disposition: proper and adequate anesthesia; irrigation; and debridement are important elements of the initial disposition.
3.1. Anesthesia: Whether it is local anesthesia, regional block anesthesia, or general anesthesia, it should ensure that the wound can be thoroughly and effectively irrigated, explored, cleared, and even closed. Most of the local anesthesia of the wound can be applied to amino compounds or esters, the former because of less side effects and easy to tolerate. 1-2% lidocaine is the most commonly used local anesthetic drugs, fast onset and long duration, without epinephrine dosage is not more than 3-5mg/kg, the dose of 7mg/kg or less when combined with lidocaine. The suggestion that the combination of epinephrine should be avoided when local anesthesia is performed in the distal limb is not supported by the literature. Attention should be paid to the appropriate additional anesthesia according to the specific situation of the wound, and general anesthesia should be activated if necessary.
3.2. Irrigation and debridement: After proper evaluation and anesthesia, irrigation and debridement are mandatory steps prior to closure of the wound by which contaminated tissue is removed to ensure eventual healing. There are a variety of irrigation modalities to choose from, as well as different types of fluids that can be used for irrigation. Since irrigation works more through physical mechanisms than through drugs, mixing antibiotics in the irrigation fluid should not be promoted.
There are also various methods of debridement, including surgical debridement with the aid of scissors, bone chisels, and scalpels. In addition, other methods available include enzymatic or mechanical power debridement, and recent studies have shown that plasma radiofrequency technology has also shown great superiority, but of course these methods require the use of specialized drugs or equipment.
4. Closure of wounds.
4.1. Simple wounds: Such wounds can be closed with the help of sutures; in addition, a variety of tools such as tape, glue, and stapler can be used as appropriate. Selective use of these tools at specific anatomic sites or for specific wounds can help to heal the wounds better. However, the orthopedic literature also suggests that skin staplers may be associated with a higher incidence of infection compared to sutures, and an ongoing randomized controlled study will provide stronger evidence for surgeons.
4.2, Complex wounds: closure of complex wounds is relatively difficult and may require second-stage or delayed closure; for such wounds, vacuum-assisted devices or dressings may be applied.
4.2.1, Negative-pressure Wound Therapy (NPWT): Negative-pressure wound therapy reduces peri-incisional edema and improves local oxygen supply to promote wound healing, in addition to removing harmful proteases and collagenases, which helps chronic wounds heal. In general, NPWT is not suitable for pressure- and ischemia-sensitive tissues. Previous studies have demonstrated its effectiveness for diabetes-related wounds, fistulas, and thoracoabdominal wounds.
4.2.2, Hydrogel: It can be applied to partially dry wounds, diabetes-related wounds, pressure sores, burns, and also to infected cases. It can maintain a certain level of humidity and thus be comfortable for the patient, but it is not suitable for wounds with more exudation.
4.2.3, Gel: These substances are characterized by their ability to create a relatively closed environment for better healing of wounds, and are therefore not suitable for infected wounds, nor for areas with abundant blood flow.
4.2.4, Foam dressing: It can be used for wounds in blood-rich areas, but generally not for dry and clean wounds.
4.2.5.Algae Gel Dressing: Extracted from natural substances such as seaweed, it is very suitable for highly exuding wounds and can absorb 20 times its own weight of liquid. Processed into specific shapes such as cords, the dressing can be used for deep wounds such as cavities, but also because of its high water absorption, it is generally not used for dry wounds.
4.2.6. Antimicrobial excipients: there are many kinds, among which the dressing with silver ions attached is probably the most effective.
5.Adjunctive treatment
5.1. Antibiotics: The principle to always keep in mind is that most properly treated wounds do not require adjuvant antimicrobial therapy. If infection is present within the wound, clues can often be detected by clinical signs.
5.2. Nutritional support: Nutritional status is crucial for immune function, wound healing, and tissue reconstruction. Therefore, correcting the nutritional status is a very important part of the process of wound treatment, and it is wise to suspend non-emergency surgery in the case of suboptimal nutritional status.
5.2.1. Protein: Various plant and animal proteins play an important role in the healing of wounds.
5.2.2, vitamin A: cofactor for collagen synthesis, can promote wound healing, green leafy vegetables, liver, egg yolk, dairy products, cereals can provide rich sources, especially for radiation damage.
5.2.3, vitamin C: another important cofactor for collagen synthesis, can be derived from citrus fruits, potatoes, tomatoes, broccoli, peppers.
5.2.4, vitamin E: contributes to immune function and the maintenance of overall health, and is important for radiation-related poor wound healing, derived from vegetable oils, whole grains, eggs, green leafy vegetables, and plant seeds.
5.2.5, Zinc: A key factor in epithelial cell formation, also improves the firmness of wound tissue, can originate from meat, fish, dairy, beans, whole grains.