This article prepared by American Plastics Surgery Educational Foundation, which is the education branch of the American Association of Plastic Surgeons, contains extensive information regarding common daily life injuries and wound healing.
After biochemical constituents of healing come together in the wound, fibroblasts start proliferating and settling. Main duty of fibroblasts is collagen synthesis. Strength of the wound area increases as collagen content is increased. Stitches should be removed between the 3rd and 14th days depending on the localization of the wound. In addition, collagen content and tensile strength of the wound improves in the following weeks; and collagen conversion in the wound continues permanently. This second phase of wound healing is called the “fibroblastic phase” or “collagen phase”.
Ascorbic acid plays an important role in collagen formation. In the absence of vitamin C, proline cannot be converted to hydroxyproline and therefore collagen synthesis stops. If we remember the sailors with scurvy in Herman Melville’s “Moby Dick”, we know now why their wounds didn’t heal for a long time. In ascorbic acid deficiency, collagen synthesis stops whereas collagen resorption continues with the same pace leading to a pause in wound healing.
The longest phase of wound healing is the last phase. This “maturation” or “remodeling” phase can last several years and it results with an improvement in the appearance of the wound. Progressive collagen replacement occurring in this period results in a scar that is soft and less visible. Maturation is important for step-by-step improving of the wound.
Wounds with skin loss
Also in acute traumatic injuries such as severe burns, deep abrasion and avulsion that result in skin loss, healing phases are the same. However, wound closing requires two additional mechanisms. These are epithelial migration and wound contraction.
Epithelialization: Right after biochemical and cellular substrates required for healing come together and as soon as bacterial contamination drops below 105 organisms/gram, epithelial proliferation starts and epithelial cells migrate to the surface of the wound. If the wound is a superficial burn or abrasion, epithelial cells start spreading rapidly from sweat glands and hair follicles and they cover the whole wound surface within 10-14 days. In case all layers of the skin are lost, epithelial cells can only migrate to the margins of the wound. Epithelialization is a very slow process and it is generally not possible for the wound to close sooner. Moreover, in this case epithelial migration is not accompanied by dermal layers and therefore it is more sensitive to trauma.
Histology of the migrating epithelium is generally of neoplastic appearance. In time, a malign ulceration, in other words a Marjolin ulcer as named after the French surgeon who first defined this phenomenon, may form on a chronic wound that does not close for years. Therefore, reconstructive surgeons learned not to lean only on epithelialization in case of severe and widespread wounds. Instead, they use grafts or flaps for wound closing.
Wound contraction: Open wounds tend to close in time due to internal forces. “Granulation” of the wound means that the surface of the wound is filled with the granulation tissue formed by capillary and fibroblast proliferation. In an open wound, forming of the granulation tissue corresponds to the fibroblastic phase of primary wound healing. After granulation, edges of the wound are pulled towards the center. However, this movement cannot be explained by epithelialization alone. The wound surface shrinking gradually is called wound contraction and this process cannot be completely explained yet. Today, it is believed that this contraction is achieved by myofibroblasts, which are highly specialized fibroblasts, through acting like smooth muscle cells.
Neither epithelial migration nor contraction can be pursued under high bacterial contamination (105 organisms/g). While partial thickness skin grafts can slow down the contraction, full thickness skin grafts can almost stop it. Also, some synthetic membranes such as Biobrane can inhibit wound contraction.
Large wound defects, on the other hand, should not be left to heal naturally since they can be treated best by surgical closure.
The target of wound healing is not wound sterilization!
In polls among doctors, questions are generally about the use of antiseptic solutions or antibiotics in preventing bacterial contamination or providing sterility.
The disadvantage of attaching too much importance on sterility is that, it may result in missing much more important factors in wound healing. However, if there is an infection, sterility is a must for skin surface.
In the absence of a traumatic injury, pathogenic and non-pathogenic bacteria exist in harmony on healthy skin. Quantitative tissue biopsy research shows that bacterial density on healthy skin is 103 organisms/g. A majority of bacteria on the skin live in epidermal indents such as sweat glands, hair follicles and other skin extensions. Therefore, skin constitutes a significant obstacle for infection.
Bacterial development on skin depends on several variables such as skin pH, dryness of outer skin layers, local secretions and such. Fatty acids produced in sebaceous glands are very effective in preventing streptococcus reproduction.
Unfortunately, an injury changes this balance significantly. Even a minimal trauma such as shaving the night before elective surgery may increase bacteria level 10 fold or more. Burns damage the keratin layer that prevents bacterial invasion. A laceration exposes deep tissue layers. Crushing impacts cause more cell damage. Problems increase when the treatment is delayed. Number of bacteria increases when the wound is contaminated with soil.
Some of commonly used cleaning solutions make the healing environment even worse. For example, solutions containing alcohol or hydrogen are also fatal for healthy cells; solutions containing strong detergents are nothing more than a physiological soap. Solutions containing high amounts of pigments, on the other hand, color the wound and prevent distinguishing between dead and living tissue.
It is a common ritual to shave the wound before performing a medical intervention. However, exaggerating this process results in patients coming to the emergency service with a small laceration on hairy skin and leaving with hairless patches. Essentially hair is dirtier than skin but it is neither sterile nor unusually contaminated. However, hair is a protein and it acts like a foreign object when it enters the wound. Therefore, hair surrounding the wound shouldn’t necessarily be shaved if proper attention is paid to keeping hair out of the wound.
How would a satisfactory wound preparation be? First of all, the wound should be washed with pressure using a syringe containing 50 cc. normal saline. This way, you act like a macrophage and remove clots, necrotic tissue, foreign objects and some of bacteria from the wound. This critical step reduces the risk of infection and increases the possibility of healing without complications by diluting existing bacteria and removing dead tissue from the healing area. Do not hesitate to apply a local anesthetic before performing this procedure; you wouldn’t spread the infection and you may even do a pretty good job resting nerve endings.
Do not put any material that can further damage the cells into the wound. Stay away from all solutions containing alcohol, povidone iodine and detergents. If you don’t know anything, you can apply a simple and balanced saline solution both as a preparation and irrigating agent.
After cleaning the wound, now you can act like a myofibroblast and bring the edges of the wound closer.
It is beneficial to emphasize the measurement of infection in wounds. Biopsy culture enables quantifying the bacterial density. Studies show that the risk of infection would be high if the wound is stitched although quantitative cultures give values more than 105 organisms/g. In case of values lower than this, infection is rarely seen unless tense closure, insufficient debridement and such technical mistakes were made. Streptococcus is an exception; it is dangerous no matter the quantity.
If you encounter badly contaminated wounds very often as a result of your job, you can choose delaying closure and ask the microbiology lab – if there is one – to support you with biopsy culturing technology. Secondary closure can be best achieved after the inflammatory phase of wound healing reduces bacterial density to a safe level.
Priorities in wound care
In acute soft tissue injuries, the most suitable care contains the following steps respectively:
Inspection: When the patient arrives, have a quick look at the wound. You will have to assess whether the bleeding is under control and if the dimensions of the wound are beyond your resources at that moment. Don’t forget to look outside the most visible wound and check for signs of other severe wounds. You may choose to share responsibility with another consulting physician for a complex wound.
Otherwise, you may be temporarily disqualified for similar and much more difficult problems. Suitable solutions in such a condition are: asking for help and acting later or if the wound is not severe, asking the patient and his/her family to wait. In the latter, you need to convince the patient and his/her family that delaying the treatment for one or two hours will not lead to a bad outcome. Make sure the patient is waiting at a comfortable place in the meantime. Before you start treatment, determine the properties of the wound and take anamnesis including patient’s medical history, allergies, previous treatments and vaccinations.
Anesthesia: A local anesthetic should be applied before any intervention of the wound. Even though dirt is visible inside the wound; first infiltrate the surface and then apply irrigation and debridement. It is not true that the injection will cause contamination to spread. Injecting directly into the wound instead of adjacent tissue will not increase the risk of infection and will also be less painful. Sufficient irrigation and debridement can only be achieved if the wound is well anesthetized. Your chance of success decreases if you are preparing the wound before applying an anesthetic.
Antiseptic solution: Many doctors are worried as to which preparation solution to use. However, this is the least important factor among others that affect the success of wound treatment.
Never use agents that damage living tissue. Preparation solutions containing alcohol, povidone iodine, peroxide or stronger detergents do more harm than good. They kill bacteria but they also kill fibroblast and epithelial cells. Solutions containing high amounts of pigments, on the other hand, change the appearance of the wound and make it harder to distinguish between dead and living tissue.
Irrigation and debridement: All wounds except for very small and superficial ones benefit from irrigation. This is the main step for preparing a wound for closing. This physiological irrigation solution dilutes the existing bacterial concentration. It also removes dirt particles and most importantly enables identifying partially disconnected fat particles and other dead tissue. These constitute food for microorganisms unless they are subjected to debridement. In order to provide the most suitable irrigation force, use a 50 cc. injector and 25-gauge needle.
Decision – Closing or not: In cases where injury occurred a long time ago or there is a severely contaminated crushing injury; it is best to delay closure for three to five days. In this period, inflammatory phase of healing reaches peak level.
One of the most important surgical lessons learned from the wars in the past is that leaving a wound, that has been treated under conditions worse than ideal, temporarily open is much more beneficial. Stitching right away poses a higher risk of infection. Maybe, the only exception to this general rule is facial injuries. Stitching a laceration on the face without delay when effective irrigation and debridement is ensured does not pose a threat since blood flow in the face and neck area is good.
Tetanus prophylaxis: Even small and insignificant wounds can cause tetanus. Therefore, it is very important to question previous tetanus prophylaxis. It is important to know the difference between a previous tetanus vaccination and complete prophylaxis requiring three injections. If there are any doubts, apply passive immunization to your patient by using a human antibody preparation.
Antibiotics: Never assume that your patient listens to everything you say. A patient wounded accidentally would rather be thinking about the causes of the accident instead of paying attention to your instructions. Be willing to repeat your words. Speak in an explanatory and simple manner. Most importantly, write important post-treatment instructions on a paper. Patients may use it later.
Instructions for patients: Asla hastanızın söylediğiniz herşeyi dinlediğini düşünmeyin. Kazayla yaralanmış bir hasta genellikle talimatlarınıza dikkat edecek yerde kazaya yol açan nedenleri düşünüyor olacaktır. Söylediklerinizi tekrarlamaya istekli olun. Açıklayıcı ve basit bir dille konuşun. Fakat hepsinden önemlisi, tedavi sonrası önemli talimatları bir kağıda yazın. Bu daha sonra hasta tarafından kullanılabilir.
Medication for acute injuries :
Unfortunately there is a common false belief that narcotics, sedatives and almost all such drugs are unsafe for the victims of traumatic injuries. This principle definitely applies to patients with multiple system injuries. However, it is not true for patients with local injuries. Don’t rule out pharmacological support for these patients. Look for intracranial trauma symptoms; if none, make sure your patient benefits from painkillers and sedatives.
If the patient has acute injury, administer all medication intravenously. Intramuscular injections are less effective and more painful for the patient. An intravenous catheter enables adding other medicine when required. This book does not include the whole pharmacological approach. It is said that simple medicines would probably be sufficient. For many patients barbiturates are ideal sedatives. Of course, you need to ask about your patients’ allergies and previous drug intolerances before administering them anything. Moreover, wait for a while for the sedative to take effect before applying local anesthesia. Local anesthetic would be more effective in a patient who has reached enough sedation.
A sedative like Nembutal is just a sedative and not an analgesic. If the patient has pain or if you expect so, a medicine to control the pain, preferably a narcotic should be prescribed. Both Morphine and Demerol are fit for the job. Use the medicine you know best. However, if the patient has developed nausea or any adverse effects against one of those, prescribe the other one.
Patients may also benefit from a short acting relaxant such as Diazepam, best administered right before the local anesthetic, in addition to a sedative or analgesic.
A good dressing should meet one or more of the functions given below.
Protection: Dressing protects the wound from additional trauma, temperature changes that stimulate pain and others’ curious eyes. A simple bandage is protective against undesired problems caused by an exposed stitched wound and against staining of clothes. Moreover, wound dressing also provides a suitable medium for optimal wound healing. When circulation is impaired, an unhealed wound cannot provide its own moisture and the resulting dryness causes an increase in tissue loss. On the other hand, wound surface may produce so much exudative leak that it leads to an unnecessary metabolic loss. Although some doctors believe that wound dressing protects the wound from bacterial contamination, a stitched wound doesn’t actually get contaminated easily after several hours post-treatment. The wound is able to protect itself after the inflammatory phase of wound healing begins, unless there is a circulation problem.
Absorption: The dressing may absorb the exudative leak on the surface of the wound. This decreases the possibility of bacterial proliferation and subsequent wound infection. A moist dressing acts like a suppository and draws water from the wound. Therefore, it prevents exudate from staying in the wound and forming a scab. Keep in mind that neither the wound surface nor the skin is sterile. Bacteria existence on both of these surfaces is inevitable. If we allow bacterial proliferation, indeed there will be a price to pay. Delaying of the wound healing and resulting in a significant scarring due to infection is an undesired outcome.
Pressure: A good dressing should apply reasonable pressure to prevent edema in the wound. However, excessive pressure that might lead to ischemia should be avoided.
Immobilization: A good dressing should also provide immobilization in the healing area. A continuously moving wound cannot heal as fast and good as an immobile wound. Effective immobilization is a must for neovascularization of skin grafts.
Properties of an ideal wound dressing
Dressing should always be in accordance with patient’s living conditions. Choice of dressing may be different in a hospitalized patient compared to another patient that was examined in the emergency room and will get back to work soon. An uncomfortable and dysfunctional dressing would worsen the patient’s adaptation. Therefore, dressings should be clean, neat and smooth on the outer layer.
The first layer of the dressing should not adhere to the wound surface. For this purpose, prefer liquid-permeable gauze dressing that is slightly lubricated. Pores of the gauze dressing are wide enough to permit liquid passage. Telfa, Saran and other impermeable materials are not suitable since they cause maceration.
The second layer should be able to absorb liquids leaking from the wound. While folded gauze dressings or pads are sufficient for small wounds, bigger wounds need more absorbing and several fluff gauzes. Cotton is a conventional constituent of gauze dressings. Moreover, synthetic materials that are highly absorbing were also produced. Covering the extremity with soft gauze dressings after fluff gauzes will increase absorption capacity and stabilize the first layer of the dressing. However, these soft materials become loose easily and they may not provide enough pressure and dressing stability. Controlled pressure with initially non-elastic dressings is the best way. Elastic bandage is not useful in such dressings. Because increased pressure may cause ischemia. If this layer of the dressing is supported by sticky tapes, the strength of the dressing increases. The target is to provide pressure, not strangulation or ischemia. Applying gauze dressing in a fluffy manner and supporting it with sticky tapes significantly helps the immobilization of the extremity. An additional splint is necessary for more immobilization. However, one should be careful while using splints. If you don’t use enough cotton, you can cause pressure and ischemia. Wound dressing should be performed deftly and have a good appearance.
Open wound care
Dressings of scratches, burns or open wounds should also have protection, absorption, pressure and immobilization functions just like in closed wounds. In addition, dressing of such wounds needs some adjustments. Damages with partial thickness such as superficial burns and scratches should be cleaned of all foreign objects and covered with a protective but not sticky layer such as Bactigras. While this layer is being lifted, the new proliferative epithelium should not be damaged. The second layer should be absorbent. While changing the dressing, upper layer is replaced without removing the first layer. The first layer detaches by itself when the wound is healed.
Wet / moist dressing
Wet-moist dressing and maybe one of the new hydrocolloid dressings is always preferred over dry dressing. Any dressing is slightly wetted while opening because dry dressing causes pain during removal. Another advantage of wet-moist or hydrocolloid dressing is that they provide a moist environment that enables epithelium migration and granulation tissue formation.
Wound care in burns
As understood from the title, we will discuss exactly what first degree burns mean in this section. Surgeons can underestimate first-degree burns. As surgeons, we can say, “first degree burns are someone else’s problem, not ours” or “first degree burns do not require a specialist or burn center”. However, this may not be true at all times.
First degree burns;
They cover generally less than 5% of the body surface.
They are partial thickness injuries
These burns do not involve face, hands, feet or genitals.
In this section, we only consider the treatment of first-degree burns. Basic principles defined herein can also be applied in larger burns; however it is recommended that you refer patients with a major burn to a specialist or a burn center.
Type of the wound
First-degree burns are like partial thickness scratches. They are superficial and they don’t go through all the skin layers. However, keep in mind that a partial thickness burn might cover all layers the next day and the depth may have been determined wrong in the beginning. Therefore, stay alert for more severe damages.
Initial treatment of burn injuries
First of all; clean the surface of the wound gently as in all other wounds. Leave small, not ruptured and not infected bullae intact so as to protect the wound surface. If bullae have ruptured perform debridement on the epithelial layer to prevent contamination. Then cover the wound with greasy gauze dressing and cover once more with absorbent material. Change the dressing every 24-48 hours. Topical antibacterial agents such as Povidone, Mafenide or Silver Sulfadiazine are not essentially required. These have limited benefits in patients with large burns and risk of sepsis. Topical antibacterial agents inhibit wound healing. If wound care were started immediately, systemic antibacterial agents would also not be necessary for small superficial burns.
Monitoring through the bullae
Don’t discharge and send your patient, who has first-degree burns, home without giving recommendations. You will need to perform following exams frequently. A partial thickness burn might be misdiagnosed and the damage may grow. If your diagnosis is correct, first-degree burns will heal within 10-12 days. If the wound extends towards dermis, healing will be delayed and sometimes hypertrophic scarring may form. Deep dermal burns heal better with skin grafts. If you think healing was not successful, consult a plastic surgeon.
Bite wounds constitute 1% of patients who come to the emergency service and there are approximately 2 million bite wounds in USA each year. Cat wounds with 5-15% follow dog wounds that constitute 80-90 % of all bite wounds. Human bites constitute less than 5%. Even though most of the bites cause small injuries, they may result in high morbidity.
Most of the time; the person that has been bit knows the dog and usually irritates it. This is more common in children. Young dogs and female dogs are more likely to bite. Although most of the bites are seen on extremities, especially little children have bite wounds on their head and neck. Deadly dog bites usually come from big dogs and frequently lead to death due to bleeding from big neck veins. 2-20% of dog bites become infected. This ratio is one of the lowest ones among mammalian bites. Bites on hands have increased risk of infection, tenosynovitis and septic arthritis. Microorganisms in oral cavity of dogs include Pasteurella Multocida, Staph. aureus, Staph. intermedius, Alpha-hemolytic streptococcus, Eikenella corrodens and Capnocytophaga canimorsus.
The risk of infection in cat bites and scratches is higher than that of dog bites. The reason is that cat teeth can easily penetrate into joints and periosteum, as they are tiny and sharp. A cat’s mouth flora is similar to a dog’s, wherein Pasteurella is the most produced microorganism in cat bites (50-70%).
Many human bites occur during fights and they generally require medical attention. A bite wound due to punching is a classic example. The patient punches someone on the mouth and teeth of the other person enters metacarpophalangeal joint letting microorganisms into the joint.
Human bites can cause serious infections. Human mouth cavity is highly contaminated and Streptococcus viridans, Staph. aureus, Eikenella, Haemophilus influenza and oral anaerobic bacteria may lead to infection.
Important points in anamnesis are; whether the treatment is delayed, tetanus vaccination status and possibility for rabies contagion. Patients with immune deficiency require more intense treatment since they carry high risk of severe infection. It is important to pay attention to the degree of smashing and fracture during physical exam; because these wounds are much more prone to infection. If the injury involves tendons and nerves, the patient should be referred to another facility for a possible surgical intervention. Joint penetration is another indication for referral. If bone or joint damage is considered, a direct X-ray should be taken. Foreign objects seen on X-ray can be teeth parts and these have to be removed. All bite wounds should be washed and cleaned thoroughly first and dead tissue debrided. Many dog bites can be closed safely if it has been more than 8 hours since the bite occurred. Cat and human bites should be left open since they carry a higher risk of infection. Bites in the form of holes should not be closed as well. Human bites on the face and on cosmetically important areas can be closed after a thorough debridement. Closing technique is the same as in other lacerations. Wounds should be monitored closely for infection after they are closed.
Prophylactic antibiotic use should be discussed. It is not a must for not infected fresh dog bites. Prophylactic antibiotic treatment is generally applied in cat and human bites. The most preferred medicine in all these wounds is Amoxicillin/Clavulanic acid. Doxycycline (contraindicated in children and pregnant women) and ciprofloxacin are preferred in patients with penicillin allergy. In a settled infection, empiric treatment can be started with these drugs and the treatment pursued according to the results of a culture.