With the possible diversity of the course of the wound process, depending on the nature of the wound, the degree of development of the microflora, and the characteristics of the immune response, they can always be reduced to three classical types of healing:
· healing by primary intention;
· healing secondary intention
· healing under the scab.
1. Healing by primary intention (sanatio per priman intentionem) occurs in more short time with the formation of a thin, relatively durable scar. Surgical wounds heal by primary intention when the edges of the wound come into contact with each other (connected by seams). The amount of necrotic tissue in the wound is small, and inflammation is insignificant.
Occasional small superficial wounds with edge separation of up to one centimeter can also heal by primary intention without sutures. This occurs due to the convergence of the edges under the influence of edema of the surrounding tissues, and they are subsequently held in place by the resulting “primary fibrin adhesive.” Thus, when this method There is no healing cavity between the edges and walls of the wound, and the resulting tissue serves only to fix and strengthen the fused surfaces.
In order for the wound to heal by primary intention, the following conditions must be met:
· absence of infection in the wound;
· tight contact of the wound edges;
· absence of hematomas and foreign bodies in the wound;
· Absence of necrotic tissue in the wound;
· satisfactory general condition of the patient.
2. Healing by secondary intention (sanatio per secundam intentionem) – healing through suppuration, through the development of granulation tissue. In this case, when healing occurs after severe inflammatory process, as a result of which the wound is cleared of necrosis. For wound healing by secondary intention, conditions are necessary that are opposite to those that promote primary intention:
· significant microbial contamination of the wound;
· significant defect skin;
· the presence of necrotic tissue;
· unfavorable condition of the patient's body.
With secondary intention, there are two phases of healing, each of which has certain differences.
In the first period, inflammation is much more pronounced, and wound cleansing takes much longer. At the border of inflammation, a pronounced leukocyte shaft is formed. It helps to separate healthy tissues from infected ones. Demarcation and lysis gradually occur. As a result, at the end of the first phase, a wound cavity is formed and the second phase begins - the regeneration phase.
6. Rules for conducting emergency treatment in case of wounds.
Treatment of fresh wounds begins with the prevention of wound infection, i.e. with carrying out all measures to prevent the development of infection. Any accidental wound is primarily infected, because microorganisms in it multiply quickly and cause suppuration.
1. An accidental wound should be subjected to surgical treatment. Currently used to treat accidental wounds operative method treatment, i.e. primary surgical treatment of wounds. Any injury must be subjected to PSO wounds.
Through PST of wounds, one of the following 2 problems can be solved:
1) Transformation of a bacterially contaminated accidental or combat wound into an almost aseptic surgical wound (“sterilization of the wound with a knife”).
2) Transformation of a wound with a larger area of damage to surrounding tissues into a wound with a small area of damage, simpler in shape and less bacterially contaminated.
We differentiate the following types surgical treatment of wounds:
1)Toilet wound.
2) Complete excision of the wound within aseptic tissues, allowing, if successfully performed, healing of the wound under the sutures by primary intention.
3) Dissection of the wound with excision of non-viable tissue, which creates conditions for uncomplicated wound healing by secondary intention.
1. Toilet wound
is carried out for any injury, but as an independent measure it is carried out for minor superficial cut wounds, especially on the face, on the fingers, where other methods are usually not used. By toileting a wound we mean cleaning it with a gauze ball moistened with gasoline, or ether, alcohol, or alcohol ( or other antiseptic) the edges of the wound and its circumference from dirt, removing adhering foreign particles, lubricating the edges of the wound with iodonate and applying an aseptic dressing. It is necessary to take into account that when cleaning the wound circumference, movements should be made from the wound outward, and not vice versa, in order to avoid introducing a secondary infection into the wound. Complete excision of the wound with the application of a primary or initially delayed suture to the wound (i.e. an operation is performed - primary surgical treatment of the wound). Wound excision is based on the doctrine of primary infection of an accidental wound.
1 - Excision stage
and dissection of the edges and bottom of the wound within healthy tissue. It should be noted that we do not always dissect the wound, but almost always excise it. We dissect in cases where it is necessary to inspect the wound. If the wound is located in the area of large muscle masses, for example on the thigh, then all non-viable tissues are excised, especially the muscles within healthy tissues along with the bottom of the wound, up to 2 cm wide. This cannot always be done completely and strictly enough. This is sometimes hampered by the tortuous course of the wound or functionally important organs and tissues located along the wound channel. After excision, the wound is washed with antiseptic solutions, thorough hemostasis is carried out and should not be washed with antibiotics - allergization.
2 – Wound stage
sutured tightly in layers. Sometimes PSO of a wound turns into a rather complex operation and you need to be prepared for this. A few words about the features of PSO of wounds localized on the face and hands. Wide surgical surgical treatment of wounds is not performed on the face and hands, because these areas have little tissue, and we are interested in cosmetic considerations after surgery. On the face and hands, it is enough to minimally refresh the edges of the wound, clean it and apply a primary suture. The peculiarities of the blood supply to these areas make it possible to do this. Indication for PSW of a wound: In principle, all fresh wounds should undergo PSW. But a lot depends on general condition patient, if the patient is very severe, in a state of shock, then PSO is delayed. But if the patient has profuse bleeding from the wound, then, despite the severity of his condition, PSO is performed.
Timing of post-surgical treatment of wounds.
The most optimal time for PCO is the first 6-12 hours after injury. The sooner the patient arrives and the sooner PSO of the wound is performed, the more favorable the outcome. This is early PST of wounds. Time factor. At present, they have somewhat moved away from the views of Friedrich, who limited the period of emergency treatment to 6 hours from the moment of injury. PCO, carried out after 12-14 hours, is usually a forced treatment due to the late admission of the patient. Thanks to the use of antibiotics, we can extend these periods, even up to several days. This is a late PST of wounds. In cases where PSC of a wound is performed late, or not all non-viable tissues are excised, then primary sutures can not be applied to such a wound, or such a wound cannot be sutured tightly, but the patient can be left under observation in the hospital for several days and if the condition further allows wounds, then sutured it tightly.
Therefore we distinguish:
1) Primary suture
, when a suture is applied immediately after a wound and PST of wounds.
2) Primary
o - delayed suture, when the suture is applied 3-5-6 days after the injury. The suture is applied to the pre-treated wound until granulation appears, if the wound is good, without clinical signs infections, in general good condition sick.
3) Secondary seams
, which are applied not to prevent infection, but to speed up the healing of an infected wound. Among the secondary seams we distinguish:
A) Early secondary suture
applied 8-15 days after injury. This suture is applied to a granulating wound with movable, non-fixed edges without scars. In this case, the granulations are not excised, and the edges of the wound are not immobilized.
b) Late secondary suture
20-30 days or later after injury. This suture is applied to a granulating wound with the development of scar tissue after excision of the scar edges, walls and bottom of the wound and mobilization of the wound edges.
PSO of wounds is not performed:
a) for penetrating wounds (for example, bullet wounds)
b) for small, superficial wounds
c) for wounds on the hand, fingers, face, skull, the wound is not excised, but a toilet is performed and stitches are applied
d) are not subject to PSO purulent wounds
e) complete excision is not feasible if the wound walls include anatomical formations, the integrity of which must be spared (large vessels, nerve trunks, etc.)
e) shock.
3. Wound dissection
. Where, due to anatomical difficulties, it is not possible to completely excise the edges and bottom of the wound, a wound dissection operation should be performed. Dissection with its modern technique is usually combined with excision of non-viable and clearly contaminated tissue. After dissection of the wound, it becomes possible to inspect it and mechanically clean it, ensuring free outflow of discharge, improving blood and lymph circulation; the wound becomes accessible to aeration and therapeutic effects antibacterial agents, both introduced into the wound cavity and especially circulating in the blood. In principle, dissection of the wound should ensure its successful healing by secondary intention.
7.Principles of local and general treatment clean and purulent wounds.
Despite many specific features different wounds, the main stages of their healing are fundamentally the same. It is possible to highlight general tasks issues facing the surgeon when treating any wound:
· fight against early complications;
· prevention and treatment of wound infections;
· achieving healing in the shortest possible time;
· full recovery functions damaged organs and fabrics.
Granulation tissue - a special type of connective tissue that is formed only during wound healing by secondary intention, promoting rapid closure of the wound defect. Normally, without damage, there is no granulation tissue in the body. Islands of granulation tissue appear in a wound that has not yet been completely cleaned, against the background of areas of necrosis, already on days 2-3. Granulations are delicate, bright pink, fine-grained, shiny formations that can grow quickly and bleed profusely with minor damage.
The role of the entire granulation system is as follows:
· replacement of wound defect, is the main plastic material;
· wound protection from the penetration of microorganisms and the ingress of foreign bodies: achieved by containing a large number of leukocytes and microphages and the dense structure of the outer layer;
· sequestration and rejection of necrotic tissue, which is facilitated by the activity of leukocytes, microphages and the release of proteolytic enzymes by cellular elements;
At normal course regeneration processes, simultaneously with the development of granulations, epithelialization begins. As a result, the wound cavity contracts and the surface becomes epithelialized. The granulation tissue that fills the wound cavity is gradually transported into mature, coarse fibrous connective tissue - a scar is formed.
Healing under the scab.
Occurs with minor injuries such as superficial skin abrasions, damage to the epidermis, abrasions, burns, etc. Under the scab, rapid regeneration of the epidermis occurs, the scab is a “biological bandage” and the scab is rejected. The whole process usually takes 3-7 days. The scab should not be removed if there are no signs of inflammation.
If inflammation develops and purulent exudate accumulates under the scab, surgical treatment of the wound with removal of the scab is indicated.
Complications of wound healing.
Wound healing may be complicated various processes, the main ones being:
1. development of infection – nonspecific purulent, anaerobic infection, as well as the development of tetanus, rabies, diphtheria, etc.
2. bleeding. Both primary and secondary bleeding may occur.
3. Divergence edges of the wound (wound failure). Viewed as severe complication healing. Particularly dangerous for penetrating wounds abdominal cavity, as it can lead to leakage internal organs(intestine, stomach, omentum, etc.) – eventration. Occurs in the early postoperative period (from 7 to 10 days), when the strength of the forming node is low and tissue tension is observed ( intestinal obstruction, flatulence, increased intra-abdominal pressure). Dehiscence of all layers of the surgical wound requires urgent re-surgical intervention.
Scars and their complications .
The outcome of the healing of any wound is the formation of a scar. The nature and properties of the scar primarily depend on the healing method.
Differences between scars healing by primary and secondary intention.
After healing by primary tension, the scar is smooth, at the same level with the entire surface of the skin, linear, in consistency indistinguishable from the surrounding tissues, mobile.
When healing by secondary intention, the scar has an irregular shape, is dense, often pigmented, and inactive. Typically, such scars are retracted and located below the surface of the skin, as granulation tissue is replaced by scar tissue. connective tissue, having a higher density and smaller volume, which leads to retraction of the surface layers of the epithelium.
The human body is very fragile, and it is susceptible to almost any mechanical influence. It is easy to cause a wound or any other injury. The same can be said about animals. For example, you can cut yourself very simply - with one awkward movement of the hand, but the wound will take a long time to heal. In several stages. The topic is very detailed, so it is worth talking about it and paying special attention to the types of wound healing.
Definition
It's worth starting with terminology. The wound is mechanical damage integrity of the skin, mucous membranes, internal organs and deep-lying tissues. In medical terms, the clinical picture of this type of injury is determined by local and general symptoms. The first of these include pain, bleeding and gaping. TO common features includes infection, shock and acute anemia. Expressed in varying degrees- it all depends on the general condition of the person and the reactivity of the body.
So, the sharper the tool that cut the tissue, the more the wound will bleed. However, it is worth knowing about one nuance. Bleeding is not always external. Often it is internal. That is, blood pours into the cavities and tissues. Because of this, widespread hematomas are formed.
The pain, in turn, can be intense to varying degrees. Its strength depends on how many receptors and nerve trunks have been damaged. And also on the speed of injury. And how pronounced the pain is depends on the affected area. The face, hands, perineum and genitals are the most sensitive places on the human body.
Basically, this general information enough to get to the heart of the topic. Now we can talk about the types and classification of damage.
Classification
If we talk about the nature of tissue damage, we can distinguish gunshot, stab, cut, chopped, bruised, crushed, torn, bitten, poisoned, mixed wounds, as well as abrasions and scratches. Each of them has its own characteristics. And it depends on them what kind of wound healing will be. Types of wound healing also differ depending on the type of injury.
Gunshot wounds and stab wounds, for example, hardly bleed. It is also difficult to determine their direction and depth by eye. Special shape puncture wounds are those caused by a blow from a hairpin, a spear, the point of an umbrella, or a sharpened stick. Cut and chopped wounds are characterized by heavy bleeding and surface defects. Those bitten often produce pus afterwards. Although abrasions are painful, they heal the fastest.
In general, the classification is very detailed; it would take a long time to list all the types. But one more nuance is worth noting. The fact is that wounds are divided into late and fresh. The first are those with which a person consulted a doctor a day after receiving an injury. These are more difficult to cure, since infection and other microorganisms have already penetrated inside. A wound is considered fresh within the next 24 hours after application. Its consequences are easier to prevent.
Specifics of tissue restoration
Healing is complex regenerative process, reflecting physiological as well as biological reaction for the injury received. It is important to know that tissues have different healing abilities. The higher their differentiation (i.e., the slower new cells are formed), the longer they will regenerate. It is well known that the cells of the central nervous system are the hardest to recover. But in tendons, bones, smooth muscles and epithelium, this process occurs quite quickly.
Talking about the types of wound healing, it must be said that they heal faster if the nerves are large blood vessels remained undamaged. The process will last a long time when foreign bodies and virulent microorganisms (infection) enter them. Wounds still heal poorly in people suffering from chronic inflammatory diseases, diabetes mellitus and heart and kidney failure.
Primary healing
We need to talk about it first. After all, types of wound healing begin with the primary. Next comes the secondary. The last type is healing under a scab.
It tightens when its edges are smooth, touch as closely as possible and are viable. Healing will occur successfully if there are no hemorrhages or cavities inside, and there are no foreign bodies. Therefore, it is important to wash the wound. This also helps neutralize infections.
This type of healing is observed after aseptic operations and full surgical treatment of the injury. This stage passes quickly - in about 5-8 days.
Secondary healing
It can be observed when one of the conditions for the primary one is missing. For example, if the edges of the fabric are not viable. Or they don’t fit closely together. Cachexia and a lack of necessary substances in the body can contribute to secondary healing. A accompanied this type tissue restoration by suppuration and the appearance of granulations. What it is? Such newly formed glomeruli of blood vessels are called granulation. In fact, this is familiar to every person since childhood, because each of us fell and tore our knees. Everyone remembers that the wounds were then covered with a crust. This is granulation tissue.
In general, types of wound healing and their characteristics are a very interesting topic. Not everyone knows that the tissue repair process occurs in three stages. First, the inflammatory phase of healing takes place (about 7 days), then the granulation phase (7-28 days). Final stage- this is epithelization. That is, the wound is covered with new, living skin.
What do you need to know?
During the process of tissue repair there are different types wound healing. Apart from the inflammatory phase, they all last quite a long time. Although this depends on the depth of the damage. But the longest stage is the formation of the epithelium. May last for about a year.
The most important phase is the notorious granulation. It is this that promotes normal healing of the wound. Granulation tissue protects other, deeper ones, preventing the penetration of infection. If it is damaged, bleeding will begin. And the healing process will begin again. Therefore, it is very important not to touch the injury and protect it from direct contact with clothing and, in general, with any other objects/things.
Interestingly, the types of wound healing in animals are no different from us. But the process is more difficult for them. Animals try to heal their wounds themselves - they constantly lick, which can cause harm. This is why cats are put on a bandage or cone after sterilization - they cannot reach the wound and lick it to an even worse state.
Healing under the scab and treatment
This is the last type of tissue repair. Healing under the scab occurs if the damage is minor. When a person has an abrasion, for example, or abrasion. It’s just that for some time after the formation of the injury, a dense crust appears (the same scab), and a new epidermis quickly forms under it. The scab then falls off on its own.
Naturally, all wounds need to be treated. And how this should be done, the doctor explains. Self-medication will not help, especially in the case of open wounds. Because in this situation it is necessary to act step by step. The first phase of treatment is treatment medical solutions that neutralize the infection. The second is preventing inflammation and swelling. For this purpose, tablets, sprays, ointments and gels may be prescribed. At the third stage, a person must, following medical recommendations, take care of granulation tissue, promoting its transformation into connective tissue.
Scars
The medical classification knows more than one type of scar. When a wound heals by primary intention, any scar can actually form. It doesn't all depend on how the fabrics are tightened. The type of scar is determined by the prerequisites for the appearance of the wound itself. Let's say surgery. The man transferred it, and the cut made with a scalpel was stitched up. This is primary healing, since the tissues are in close contact and there are no infections. But it will still be called a surgical scar.
Another situation. A man was cutting tomatoes with a sharp knife and accidentally hit his finger with the blade. A domestic accident, one might say. But the type of healing is still the same, primary. However, it will be called an accident scar.
There are also keloid, normotrophic, atrophic and However, they are not related to the topic. It is enough just to know about these types of scars.
Causes of impaired wound healing
Finally, it’s worth saying a few words about why tissues sometimes recover so slowly. The first reason is the person himself. But violations appear even without his participation. You should consult a doctor if there is a change in pus, or if the severity of the wound increases. This is not normal and an infection is possible. By the way, to prevent it from appearing, it is important to constantly wash the wound.
You also need to know that the skin of an adult heals more slowly than that of teenagers, for example. Also, in order for the wound to heal faster, you need to support normal level moisture in tissues. Dry skin does not heal well.
But if the wound is serious and any abnormalities are observed, you need to consult a doctor and not self-medicate.
Healing by primary intention (primary healing) is observed when the edges and walls of the wound are close, touching. The healing processes proceed quickly, without the development of complications, with the formation of a thin linear scar and epithelization along the line of connection of the wound edges.
Healing by secondary intention (secondary healing) is observed when there is a large wound cavity, its edges do not touch, or it has developed purulent infection in the wound. Regeneration processes proceed slowly, with pronounced purulent inflammation, and after cleansing the wound and developing granulations, it heals with the formation of a scar.
Healing under a scab occurs with superficial wounds of the skin (abrasions, scratches, burns, abrasions), when the wound is covered with a scab (crust) of dried blood, lymph, interstitial fluid, and dead tissue. Under the scab, the process of filling the defect with granulations takes place, and regenerating epidermis creeps from the edges of the wound, the scab falls off, and the wound is epithelialized.
32. General principles treatment for fresh wounds. Primary, secondary and repeated surgical treatment of wounds, its rationale, technique. Sutures (primary, primary delayed, secondary). Principles of treatment for infected wounds. General and local treatment: physical, chemical, biological.
First aid on prehospital stage involves stopping bleeding, applying an aseptic dressing and, if necessary, transport immobilization.
The skin around the wound is cleaned of contamination, lubricated with 5% iodine tincture, loose large foreign bodies are removed and an aseptic bandage is applied.
Primary surgical treatment (PST) of wounds- main component surgical treatment with them. Its goal is to create conditions for rapid wound healing and prevent the development of wound infection.
There are early PST, carried out in the first 24 hours after injury, delayed - during the second day and late - after 48 hours.
The task when performing PCS of a wound is to remove non-viable tissues and the microflora found in them from the wound. PSO, depending on the type and nature of the wound, consists of either complete excision of the wound or its dissection with excision.
Complete excision is possible provided that no more than 24 hours have passed since the injury and if the wound has a simple configuration with a small area of damage. In this case, PST of the wound consists of excision of the edges, walls and bottom of the wound within healthy tissues, with the restoration of anatomical relationships.
Dissection with excision is performed for wounds of complex configuration with large area damage. In these cases, primary wound treatment consists of the following points;
1) wide dissection of the wound;
2) excision of deprived and contaminated soft tissues in the wound;
4) removal of loose foreign bodies and bone fragments devoid of periosteum;
5) wound drainage;
6) immobilization of the injured limb.
PST of wounds begins with treatment surgical field and delimiting it with sterile linen. If the wound is on the scalp of the body, then first shave the hair 4-5 cm in circumference, trying to shave from the wound * periphery. At small wounds Local anesthesia is usually used.
Treatment begins by grasping the skin in one corner of the wound with tweezers or Kocher clamps, lifting it slightly, and from there gradually excising the skin along the entire circumference of the wound. After excision of the crushed edges of the skin and subcutaneous tissue widen the wound with hooks, inspect its cavity and remove non-viable areas of the aponeurosis and muscles. Existing pockets in soft tissues open with additional incisions. During primary surgical treatment of a wound, it is necessary to periodically change scalpels, tweezers and scissors during the operation. PSO is performed in the following order: first, the damaged edges of the wound are excised, then its walls and, finally, the bottom of the wound. If there are small bone fragments in the wound, it is necessary to remove those that have lost contact with the periosteum. During PHO open fractures bones, the sharp ends of fragments protruding into the wound should be removed with bone forceps, which can cause secondary injury to soft tissues, blood vessels and nerves.
The final stage of PST of wounds, depending on the time from the moment of injury and the nature of the wound, may be suturing its edges or draining it. Sutures restore anatomical continuity of tissue, prevent secondary infection and create conditions for healing by primary intention.
Along with the primary, there are secondary surgical wound treatment, which is undertaken for secondary indications due to complications and insufficient radicality primary processing for the treatment of wound infection.
The following types of seams are distinguished.
Primary suture - applied to the wound within 24 hours after injury. The primary seam is finished surgical interventions during aseptic operations, in some cases and after opening abscesses, phlegmons (purulent wounds), if provided in postoperative period good conditions for wound drainage (use of tubular drainages). If more than 24 hours have passed since the injury, then after PSO of the wound, no stitches are applied, the wound is drained (with tampons with a 10% sodium chloride solution, Levomi-kol ointment, etc., and after 4-7 days until granulation appears, provided that the wound has not become suppurated, primary delayed sutures are applied.Delayed sutures can be applied as provisional sutures - immediately after PSO - and tied after 3-5 days, if there are no signs of wound infection.
A secondary suture is applied to the granulating wound, provided that the danger of wound suppuration has passed. There is an early secondary suture, which is applied to granulating PCS.
A late secondary suture is applied more than 15 days from the date of surgery. Bringing the edges, walls and bottom of the wound closer together in such cases is not always possible; in addition, the growth of scar tissue along the edges of the wound prevents healing after their comparison. Therefore, before applying late secondary sutures, the edges of the wound are excised and mobilized and hypergranulations are removed.
Primary surgical treatment should not be performed if:
1) minor superficial wounds and abrasions;
2) small puncture wounds, including blind people, without damage to the nerves;
3) with multiple blind wounds, when the tissues contain a large number of small metal fragments (shot, grenade fragments);
4) through bullet wounds with smooth entry and exit holes in the absence of significant damage to tissues, blood vessels and nerves.
A distinction is made between wound healing by primary intention (sonatio per secundum intentionem) and secondary (sonatio per secundum intentionem).
If the edges of the wound are smooth, not bruised, and fit tightly to each other, healing proceeds quickly within 6 to 8 days. This type of wound healing is called primary intention and is characterized by fusion of the wound edges without macroscopically visible intermediate tissue. -> this is possible if there is no infection, hematoma, foci of necrosis, foreign bodies in the wound, with a small area of damage, viable tissue, complete and tight contact of the edges of the wound without tissue tension.
Wounds heal by primary intention after net transactions, aseptic, as well as random wounds after primary surgical treatment, when damaged tissue is excised within healthy areas and converted into aseptic wounds with suturing.
The healing process by primary intention is the most advanced type of regeneration, since it does not leave behind large scars, is clinically easier and ends in a shorter time. With this option of wound healing during the wound process also in mandatory all the main components are present - vascular reaction, inflammation, proliferation of blood vessels and connective tissue cells, their formation of collagen and elastic fibers, but they are expressed to a minimal extent.
Secondary tension differs from the primary one in that between the edges of the wound there is a cavity caused by a tissue defect. Clinically, healing takes a long time due to the need to fill the cavity with granulations.
Healing by secondary intention occurs when there is a stitched surgical wound, the presence foreign body or blood clots, necrotic - K1<х тканей, а также при отсутствии пластической способности тканей вследствие истощения, кахексии, авитаминоза, нарушения обмена, пперек- 111111 в Рапе или организме.
From a biological point of view, there is no fundamental difference between oi zapvls-n »i and primary intention. First, the surface of the wound is covered with a layer of blood cells mixed with a layer of fibrin, forming a fiO-Rinous film that protects the wound purely mechanically.
GL \IN \ MP. DIAGNOSTICS II TREATMENT OF INJURIES
With infection, damage and death of the tissues forming the bottom and edges of the wound, symptoms of inflammation develop, manifested by swelling, hyperemia, fever, pain, and the bottom of the wound becomes covered with serous-gnopus discharge.
The development of inflammatory phenomena depends on the degree of tissue reaction and the virulence of the infection. Usually after 48 hours, and often after a week, granulations appear in certain areas of the wound, the number of which gradually increases and fills the entire surface of the wound, crevices and pockets, and even protrude somewhat above the skin level.
Microscopically, during secondary intention, due to the gaping of the wound, the newly forming capillaries do not connect with the vessels of the opposite side, as happens during primary intention, but, bending, form capillary loops that serve as a framework for granules. The vascular network grows into the fibrinous layer, as with primary intention, and newly formed cells, fnbroblasts, gradually create fibrous connective tissue.
The granulations are covered with a fibrin network, separate the purulent, cell-rich effusion, the so-called “wound secretion”, and, along with ensuring wound healing, serve as a biological defense against infection and toxins.
Epithelialization of a granulating wound begins in the first days, however, during the period of filling the wound with granulations, it is insignificant, but by the time the defect is filled, the formation of epithelium spontaneously accelerates. If the granulation tissue is young, with well-developed vessels, then the epithelium is strong. In the case when granulations are covered with necrotic cells or coarse fibrous tissue has formed, the epithelium, growing, dies and epithelialization is delayed, long-term non-healing wounds and ulcerating scars are formed.
From the ends of the destroyed nerve branches of the skin and the edges of the wound, the regeneration of nerve fibers begins, which, growing, go to the epithelium and form receptors there. Regeneration is slow; only after two weeks can one notice the growth of fibers at the edges of the wound.
Despite the lack of differences in the biological essence of primary and secondary wound healing, it is still possible to identify a number of distinctive features between them.
g™™™ 0 ™" " R " healed """ Wounds by primary intention are not significant. and secondary intention demarchenocoZT eHHe 3aBe Pshae ™ sequestration of delimited non-"extrasusonic masses, their purulent melting and discharge from the wound
CHAPTER XIII. DIAGNOSIS AND TREATMENT OF INJURIES
out with pus. This suppuration is the main feature of secondary intention, which is otherwise called “healing by suppuration.”
During primary intention, the filling of the wound gap with young connective tissue and the formation of a scar from the latter occur largely in parallel, which is why it is impossible to clearly distinguish between the second and third periods of the wound process. At the same time, with secondary tension, the phasic nature of the wound process is more distinct.
During healing by primary intention, the process of filling the wound with newly formed tissue can be observed only under a microscope; during healing by secondary intention, granulation tissue is formed in large quantities and is clearly visible to the naked eye. For this reason, healing by secondary intention is also called “healing by granulation.”
With the “normal” course of primary intention, the formation of a young scar occurs by the 6-7th day. Subsequently, over the course of several weeks, the maturation and restructuring of the scar continues, its compaction due to an increase in the number of collagen fibers with the reduction of cells and blood vessels. At the same time, nerve endings grow into the scar. The finally formed scar usually has a linear shape, is narrow and has little gene replacement. Healing by secondary intention takes much longer with the formation of a rough and, in some cases, keloid scar.
For very superficial wounds that do not penetrate all layers of the skin (abrasions), healing occurs under a scab consisting of fibrin, leukocytes and red blood cells. In the absence of infection, healing of a wound with a small skin defect under a scab occurs within a few days. In this case, the epithelium quickly spreads over the entire surface of the wound, after which the scab disappears.
The wounds are healing by primary or secondary intention and under the scab.
Wound healing by primary intention.
This type of wound healing characterized by mild signs of inflammation and absence of suppuration. The edges and walls of the wound grow together without the formation of a large amount of scar tissue. The whole process wound healing primary intention lasts 6-8 days.
At the site of the healed wound, a small scar remains, which initially has a pink color and then becomes lighter.
Healing of a wound by primary intention is possible provided that its edges and walls are completely brought together while tissue viability is maintained and there is no dead tissue, foreign bodies, blood clots or signs of suppuration in the wound.
Granulation tissue secretes a wound secretion that mechanically cleanses the wound and has a bactericidal effect. With the help of granulation tissue, dead tissue is separated (demarcated) from living tissue and the wound cavity or tissue defect is filled.
Only intact granulation tissue has these protective properties. All accidental wounds, as a rule, contain various pathogenic and non-pathogenic microbes. However, the clinical manifestation of the vital activity of the latter is not the same, which depends on the pathogenicity of microbes, the condition of the wound, the immunobiological properties of the body and a number of other conditions.
Healing of wounds under the scab.
With this type of healing, superficial wounds, abrasions, scratches, bedsores, burns are covered with a dark brown crust - a scab consisting of coagulated blood and lymph along with wound exudate.
The scab well protects the wound from mechanical influences and contamination, keeps the edges of the wound in a state of relative immobility, and prevents drying out of the granulation.
Healing of wounds under a scab occurs according to the type of primary or secondary intention. In the first case, the entire wound healing process proceeds dryly, and the scab falls off on its own after epidermization is complete. If an infection develops with profuse suppuration, the scab peels off prematurely and the wounds heal by secondary intention.
Loading...