Chemical peeling has a long history in the treatment of dermatological diseases, and in recent years, dermatology has gradually adopted the small relative molecular mass of fruit acids, namely glycolic acid, for the chemical peeling treatment of some dermatological diseases. In order to standardize the application of chemical peeling with glycolic acid and provide a safe and effective means for the treatment of dermatological diseases and medical aesthetics, the Dermatology and Aesthetics Group of the Chinese Society of Dermatology and Venereology organized experts to discuss and develop this consensus.
The chemical structure of fruit acid is α-hydroxy acid (AHA), which is a series of α-hydroxy carboxylic acid extracted from fruits and yogurt. Its relative molecular weight from small to large is ethanoic acid, lactic acid, malic acid, tartaric acid, citric acid. Due to the small relative molecular weight of fruit acids, water solubility and permeability are strong, especially the smallest relative molecular weight of glycolic acid skin permeability is the strongest, more suitable for chemical peeling agents. The fruit acid in this consensus refers to glycolic acid, which is a chemical peeling agent with little damage to the skin and has the effect of improving skin tone and rejuvenation.
I. Chemical peeling mechanism of fruit acids
At the same time, fruit acids can also activate the metabolism of keratin-forming cells, renew or rebuild the epidermis, and promote the elimination of melanin particles to reduce pigmentation.
2, the effect of fruit acid on the dermis: fruit acid can start the damage reconstruction mechanism, activating the dermal fibroblast synthesis and secretion function, so that the collagen fiber, elastic fiber density increased, the skin is tighter and more elastic. Fruit acid can also stimulate the synthesis of endoglucosamine and other intercellular matrix, promote the release of more hyaluronic acid from the dermis, enhance the water retention capacity of the skin and make the skin soft and moist.
Second, the depth of fruit acid peeling.
The higher the concentration of fruit acid and skin exfoliation, the deeper the effect, thus causing exfoliation from the stratum corneum to the papillary layer of the dermis, which works on the epidermis and dermis. The longer the dwell time of the same concentration of fruit acid, the stronger the effect of transdermal absorption. Therefore, in clinical operation, different concentrations of fruit acids and their action time can be selected according to the treatment purpose.
Indications and contraindications
1. Indications: Acne, enlarged pores, aging skin, chloasma and other pigmented skin diseases, superficial scarring, other skin diseases such as periorbital keratosis, ichthyosis, skin amyloidosis, etc.
2. Contraindications: sites and traumas to be operated on; allergic skin diseases such as contact dermatitis, eczema or skin sensitivity in the area of application; infectious diseases such as herpes simplex and impetigo; those who have received radiotherapy, cryotherapy and dermabrasion in the last 3 months; sunburn, insufficient photoprotection and uncooperative treatment; psychiatric patients or emotionally unstable people; patients with immunodeficiency diseases; pregnant and lactating women; allergic to fruit acids.
IV. Treatment methods
Fructic acid chemical peeling is commonly used in concentrations of 20%, 35%, 50% and 70%, generally starting from low concentration and gradually increasing the concentration. The concentration can also be adjusted according to the mechanism of action of different skin diseases and the reaction of the patient’s skin during treatment or maintained with a certain therapeutic concentration to achieve the best therapeutic effect. In order to control the depth of chemical peeling, it is necessary to use alkaline solution for neutralization to block the further transdermal absorption of fruit acids on the skin in time. The commonly used neutralizing solution is 10% sodium bicarbonate.
The starting concentration is 20% for the face and neck, and the starting residence time is 1-3 min; the starting concentration is 20% or 35% for the extremities and trunk, and the starting residence time is 3-5 min, increasing according to the efficacy and tolerance level. Continue to use the same concentration until the skin can safely tolerate this concentration up to 5-7 min, thicker skin parts or lesions can be extended to 10 min as appropriate before considering the choice of a higher concentration of fruit acids. If you receive treatment again more than 3 months after the acid treatment, you still need to start from 20% concentration, depending on the skin reaction after treatment and the purpose of treatment, the interval between two treatments is 2-4 weeks, and 4-6 times is a course of treatment. The specific operation steps are as follows.
1.Pre-operative preparation.
① Doctor-patient communication: inform the patient of the purpose of treatment, time, course of treatment, possible efficacy, adverse reactions, etc. Remind patients that they should not use perm, scrub, or other treatments that damage the skin barrier for 1 week before surgery, and pay attention to sun protection. Clarify the patient’s skin type, presence of pigmentation, skin allergy, viral infection, history of photosensitivity, medication use, etc.; understand the patient’s current cosmetic use, history of traumatic cosmetic treatment, etc. Discuss with the patient to develop a reasonable treatment goal and plan. (i) Patients are required to sign an informed consent form before the operation and routinely take pictures of the patient’s face in front and side position.
②Preparation supplies: 1-2 ml of fruit acid solution (20%, 35%, 50%, 70% as needed), syringe extraction; neutralization solution (10% sodium bicarbonate). Auxiliary supplies: cold water, sterilized cotton pad, petroleum jelly, cotton swab, small bowl and brush, timer, makeup remover/cleanser, mask, cream/lotion, sunscreen, etc.
2. Procedure: The following steps are performed on the face as an example.
Step 1 cleansing and protection: The patient lies flat with hair wrapped in a towel/surgical cap, cleans the face and pat dry the water. To avoid irritation or excessive acid stay, protect the inner and outer canthus of the eyes, corners of the mouth, nostrils and other cavity parts with 3-4 layers of wet cotton swabs dipped in Vaseline ointment or non-irritating cream.
The second step is to apply the fruit acid: the patient closes the eyes and the operator starts from the forehead hairline in the full face (except the eyelids and broken areas) to apply it quickly and evenly once, the application process does not exceed 30s and is monitored with a timer. One additional application can be made in the lesion area. Observe the skin reaction: during the stay of fruit acids, slight redness, itching, pain and burning of the skin are normal reactions. If there is obvious flushing, pain or even blistering, etc., it is a sign of acid overdose and should be neutralized immediately.
The third step is to neutralize the fruit acid: after applying the fruit acid, you can do the whole face neutralization at the right time according to the skin reaction and tolerance. If the application of fruit acid liquid <1
min, the patient shows rapid local redness and stinging sensation, while other parts can be tolerated, do local neutralization; if the patient has obvious stinging sensation on the whole face, do whole face neutralization immediately. When neutralizing, spray 10% sodium bicarbonate solution evenly on the face to neutralize the residual acid on the skin surface until white foam is no longer produced. If the patient complains of local irritation, spray the neutralizing solution again on the area that still has irritation. The neutralization time should not exceed 5 min.
Step 4 Calming and soothing: Remove the wet cotton pad covering the eyes and wipe off any residual petroleum jelly or cream. Spray machine to do cold spray, or use mask or cold water gauze/towel on the whole face for roughly 10-20min to reduce skin heat, reduce discomfort such as redness and irritation. After surgery, apply moisturizing and sunscreen medical skin care products to the whole face.
3. Postoperative care: cold compresses should be applied immediately after surgery, and hyaluronic acid and collagen masks should be used, and soothing moisturizing medical skincare products and sunscreen should be applied to relieve the discomfort of redness, swelling and burning.
V. Adverse reactions and prevention
During the treatment process, temporary erythema, swelling, tingling, burning and other discomfort may occur in the treatment area. Local redness and pain may occur 1-2d after surgery; crusting or flaking may occur in 3-7d, let it fall off naturally, cold compress after surgery can relieve the symptoms, avoid exposure to overheated environment within 7d, such as: hot water scalding, hot spring, sauna, avoid using with other keratin exfoliators at the same time. In seasons or areas with strong light exposure, strict sun protection and standardized use of sunscreens should be applied.
Rare adverse reactions: skin pigmentation abnormalities, burns, vesicles, temporary acne exacerbation, capillary dilation and milia. Rare adverse reactions: contact urticaria, scarring, contact dermatitis or infection. Pre-operative and intra-operative procedures should be strictly followed, and once the above adverse reactions occur, symptomatic treatment should be taken promptly according to the situation.