Classification of medical dressings

Basic introduction
Medical dressings are wound dressings, medical materials used to cover sores, wounds or other injuries.
With the in-depth study of the pathophysiology of wound healing, people have a deeper understanding of the wound healing process, which has led to the continuous improvement and development of medical wound dressings. Compared with the early days, new wound care dressings have undergone revolutionary changes, and a variety of medical dressings with different properties are available for clinical nursing staff to choose from.
Features
Natural gauze
(cotton pad) This is the earliest and most widely used type of dressing.
Advantages:
1. Powerful and fast absorption of wound exudate
2. Relatively simple production and processing process
Disadvantages:
1. Too high permeability, easy to dehydrate the wound
2. Adhesion to the wound, causing secondary mechanical damage when changing
3. Microorganisms in the external environment can easily pass through, and the chance of cross infection is high
4. High dosage, frequent replacement, time-consuming, and painful for patients
Due to the reduction of natural resources, the cost of gauze is also gradually increasing. Therefore, in order to avoid excessive use of natural resources, the application of polymer materials (synthetic fibers) to process into medical dressings has emerged, which is synthetic fiber dressings.
Synthetic fiber dressings
This type of dressing has the same advantages as gauze, such as economy and good absorption performance, etc. Moreover, some products are self-adhesive, making them very convenient to use. However, this type of product also has the same disadvantages as gauze, such as high permeability and no barrier to particulate pollutants in the external environment.
Polymer film dressing: This is a relatively advanced dressing that allows oxygen, water vapor and other gases to pass freely, while particulate foreign matter in the environment, such as dust and microorganisms, cannot pass through.
Advantages:
1. Block environmental microorganisms from invading the wound surface to prevent cross infection
2. It has moisturizing properties, keeps the wound surface moist, and will not stick to the wound surface, so as not to cause secondary mechanical damage when changing
3. It is self-adhesive, easy to use, and transparent, which is convenient for observing the wound surface
Disadvantages:
1. Poor ability to absorb exudate
2. Relatively high cost
3. The skin around the wound surface has a high chance of maceration, so this type of dressing is mainly used for wounds with little exudation after surgery, or as an auxiliary dressing for other dressings.
Foamed polymer dressing
This is a type of dressing made by foaming polymer materials (PU), and the surface is often covered with a layer of polymer semipermeable membrane, and some are also self-adhesive. Main
Advantages:
1. Rapid and powerful absorption of exudate
2. Low permeability, keeping the wound moist and avoiding secondary mechanical damage when changing dressings
3. The barrier performance of the semipermeable membrane on the surface can prevent the invasion of environmental particulate foreign matter such as dust and microorganisms, and prevent cross infection
4. Easy to use, good compliance, suitable for all parts of the body
5. Heat insulation and buffering of external impact
Disadvantages:
1. Due to the strong absorption performance, it may affect the self-debridement process for low-exudation wounds
2. Relatively high cost
3. Due to opacity, it is not convenient to observe the wound
Hydrocolloid dressings
The main component is a hydrocolloid with very strong hydrophilic ability -------- sodium carboxymethyl cellulose particles (CMC), which together with low-allergic medical viscose, elastomers, plasticizers, etc. constitute the main body of the dressing, and its surface is a semipermeable polymer membrane structure. After this dressing comes into contact with wound exudate, it can absorb the exudate and form a gel to prevent the dressing from sticking to the wound. At the same time, the semi-permeable membrane structure on the surface allows oxygen and water vapor to exchange, but also has a barrier property against external granular foreign matter such as dust and bacteria. Advantages:
1. It can absorb wound exudate and some toxic substances
2. It keeps the wound moist and retains the bioactive substances released by the wound itself. In addition to providing an optimal microenvironment for wound healing, it can also accelerate the wound healing process
3. It has a debridement effect
4. It forms a gel to protect exposed nerve endings and relieve pain. At the same time, it will not cause secondary mechanical damage when changing the dressing
5. It is self-adhesive and easy to use
6. It has good compliance, the user feels comfortable, and the appearance is hidden
7. It blocks the invasion of external granular foreign bodies such as dust and bacteria, and the number of dressing changes is small, thereby reducing the labor intensity of nursing staff
It can save costs by accelerating wound healing
Disadvantages:
1. The absorption capacity is not very strong, so for highly exudative wounds, other auxiliary dressings are often needed to enhance the absorption performance
2. The product cost is relatively high
3. Some patients may be allergic to the ingredients
It can be said that this is a relatively ideal dressing. Decades of clinical application experience abroad have shown that hydrocolloid dressings are particularly effective for chronic wounds.
Alginate dressing
Alginate dressing is one of the most advanced medical dressings. The main component of alginate dressing is alginate, which is a natural polysaccharide carbohydrate extracted from seaweed and a natural cellulose.
Alginate medical dressing is a functional wound dressing with high absorption performance composed of alginate. After the medical film comes into contact with wound exudate, it can form a soft gel, providing an ideal moist environment for wound healing, promoting wound healing and relieving wound pain.
Mechanism of action:
1. Safe and non-toxic: Alginate medical film is a natural polysaccharide carbohydrate extracted from seaweed. It is a natural polymer material that has no toxicity to the human body and can be used safely.
2. High hygroscopicity: Alginate medical film can absorb liquid equivalent to 11 times its own weight.
3. Hemostasis: Alginate medical film releases Ca2+ when in contact with wound exudate, which can promote the formation of prothrombin activator and accelerate the blood coagulation process.
4. Gelatinization: absorb wound exudate, exchange Na+/Ca2+ ions with the exudate, and form a layer of stable mesh gel on the wound surface. Create a microenvironment for the wound that is conducive to tissue growth (slightly acidic, anaerobic or hypoxic, moderately moist).
5. Promote wound healing: The slightly acidic, anaerobic or hypoxic, moderately moist wound environment promotes the release of growth factors, stimulates cell proliferation, improves the regeneration ability and cell movement of epidermal cells, and promotes wound healing.
6. Antibacterial properties:
①. Good sealing, which isolates the wound from external bacteria;
②. Harmful bacteria are fixed inside the fiber, effectively inhibiting the reproduction of harmful bacteria and reducing the chance of contact between bacteria and the wound;
③. The moist and slightly acidic environment is conducive to the role of neutrophils, enhancing local bactericidal ability and reducing the incidence of infection.
7. Reduce local pain: The hydrogel formed on the surface effectively protects nerve endings and avoids external stimulation; it is not easy to adhere to the wound, easy to remove, and reduces wound pain.
8. Reduce scar formation: Since there is no irritation or damage to the wound surface, there is less scar formation.
Advantages:
1. Strong and rapid ability to absorb exudate
2. Forming gel, which can keep the wound surface moist and non-sticky, protect exposed nerve endings, and relieve pain
3. Promote wound healing;
4. Biodegradable, good environmental performance;
5. Reduce scar formation;
Disadvantages:
1. Most products are not self-adhesive and require auxiliary dressings to fix
2. Relatively high cost