When a person contracts a wound, wound secretion formation begins. Wound secretion is also called wound fluid and is a watery secretion that can, but does not have to, come out of a wound. The size, condition and degree of cleanliness, or contamination with pathogens, plays a role. If contamination is present, there is always a risk of ongoing, prolonged wound healing, secondary infection, and sepsis.
What is wound secretion?
Wound secretion is also known as wound fluid and is a watery secretion that can, but does not have to, leak from a wound. Wound secretions form due to a variety of processes. As a result of the skin defect, the body begins to produce more lymph fluid. The composition can vary greatly, often containing proteins and occasionally blood. If an infection is present, the secretion contains appropriate microorganisms and the body’s own defense cells. The secretions of viruses and bacteria form pus. Wound secretions are classified into several types. Secretions to the outside, which are inflammatory, are called exudates. They contain a high concentration of proteins and can be viscous or thin. The color varies from clear to yellowish, to a reddish hue. It depends on the components, for example, whether many white or red blood cells are contained. Macromolecules, such as blood cells or proteins, pass through the vessel wall into the surrounding tissue or to the tissue surface. Exudates are further subdivided according to their components into purulent, bloody, fibrinous or serous exudates. Wound exudates that are not secreted externally but inside the body, where they form a cavity, are called seroma. This often occurs in the area of wounds on the surface of the skin, for example, after surgery. There is swelling, which is usually not painful and not discolored. Nevertheless, wound healing is impaired because the pressure on the tissue reduces blood flow. As it progresses, bacteria can form and inflammation can result.
Function and task
The formation of wound secretions is an important function in the healing process. Germs and foreign bodies are flushed out of the wound, which can otherwise cause complications. Cells and hormones of the immune system are involved in this process to kill invading bacteria or viruses and stimulate the healing process. The blood components exuding from the tissue initiate wound closure. The exudative phase in wound healing is also referred to as “tissue perfusion”. It is the prerequisite for dead tissue to be flushed out and cell growth to be stimulated. For cell division, the body requires a moist, warm environment; the wound surfaces must not dry out. Superficial wounds are closed by coagulated wound fluid, scabs are formed. On wounds that constantly secrete a lot of fluid, no crust can form and they heal very badly. Too much secretion is a breeding ground for bacteria. Wound dressings with different properties and different methods should support healing. For example, if too much secretion is formed, absorbent dressings or gauzes are used. Non-infected, cleaned, dry wounds are kept moist.
Diseases and ailments
If wound secretions cannot drain, complications often occur. If a wound secretes purulent secretions into the interior of the body, forming an encapsulated cavity, it is called an abscess. Abscesses are often caused by bacterial infections, but there are also abscesses in which there are no bacteria. These are called sterile abscesses. Abscesses may be continuous or in chambers. They may spread further and assume considerable dimensions. As they progress, the tissue may become encapsulated, the fluid may calcify, or fistula tracts may form through which secretions can drain. Abscesses can occur in the skin, but also in almost all organs. Abscesses are usually opened surgically so that the wound fluid can drain to the outside. If wound secretion flows into an existing body cavity, for example into a joint space, this is referred to as an effusion. If a collection of pus is encapsulated, this is called an empyema. This can occur, for example, either in an organ, such as the gallbladder, or in body cavities, such as the maxillary sinuses.Imaging techniques such as ultrasound or X-ray are helpful for diagnosis. Empyema is usually treated by surgical evacuation and, if necessary, with antibiotics and drainage. As a further complication, so-called phlegmons can form. In this case, the purulent wound fluid spreads in the connective tissue, in and around muscles, fasciae and tendons. Symptomatically, phlegmon is manifested by a considerable impairment of the general condition, fever above 39° and a painful, reddish, hyperthermic swelling. The infection spreads and thus destroys body tissue. As it progresses, it can lead to purulent melting of the tissue, which in turn leads to tissue death. If a phlegmon is not treated or is treated inadequately, there is a risk of blood poisoning, which can become life-threatening. Abscesses can form, which can affect muscles, tendons and the abdominal cavity. Phlegmon is primarily treated with medication. High-dose administration of antibiotics, possibly also local antiseptics and immobilization are the first priority. Furthermore, the affected area can be surgically opened and cleared out. If the wound fluid contains a high proportion of red blood cells, or if blood leaks from injured vessels into the surrounding tissue, this is referred to as a hematoma. Hematomas are usually caused by external violence, such as blows, impacts or falls. They can also occur after surgery. A hematoma can swell severely and hurt, but they usually heal on their own.
