eMedicine Specialties > Plastic Surgery > Skin

Skin Resurfacing, Chemical Peels

Author: Gregory Caputy, MD, PhD, FICS, Chief Surgeon, Aesthetica Plastic and Laser Surgery Center, Inc
Contributor Information and Disclosures

Updated: Mar 28, 2008

Introduction

The application of chemicals to the skin is a well-described method to attempt to restore a more youthful appearance. Chemical peeling is the chemical removal of layers of skin to improve dermatologic defects. For information on other skin resurfacing techniques, see the Skin section of eMedicine’s Plastic Surgery journal.

History of the Procedure

Chemical peels currently are performed commonly by many different medical and paramedical personnel and laypersons. The lay peelers of the 1920s dominated the field and then essentially were attacked legally and placed at a legal disadvantage by the medical peelers, who often sent their wives in for peels to learn the secret arts. Chemical peeling did not become prominent in plastic surgery literature until 1960.

Sir Harold Gillies used pure carbolic acid in a painting and taping technique for correction of "slight laxity of the lid" for many years prior to 1960. Also prior to that time, dermatologists used phenol peels to remove superficial blemishes, and lay peelers gave peels a mixed notoriety. These lay peelers, largely in California and Florida, had developed effective peeling solutions and concoctions. In September of 1961, Litton presented 50 patients with 2-year follow-up periods on whom chemical peels had been performed using a minute amount of croton oil in a 50% solution of phenol with glycerin and water. He had paid Coopersmith, a lay peeler in Fort Lauderdale, for the formula in 1958 or 1959. He published his findings in 1962 but did not include a specific formula in the article.¹

Concurrently, Brown and the surgeons and dermatologists who followed him popularized and refined the technique. In November of 1961, Baker contributed a specific and easily measured formula, with one patient identified with a 3-month follow-up period.² Baker had approached a lay peeler in Miami, Miriam Maschek, and Coopersmith to discuss the formula. In 1962, Baker published the formula that essentially remained unchanged—to the exclusion of all others—for the next 35 years.³

In recent years, a large shift has occurred in the manner and depth to which peels are performed. Lasers largely have supplanted deep chemical peeling because of the control of depth they afford, their lesser effect on pigmentation, and their ease of use, with no chemical adverse effects. Superficial peels, in contrast, have increased in popularity. Various agents are used; for simple exfoliation, glycolic or lactic acids are now commonly found in almost all moisturizers and in many makeup bases.

Problem

Aging skin undergoes a number of changes. With time, it thins, falls, and creases along muscular and gravitational folds. Compared to the effects of simple aging on skin, sun damage leads to additional and different problems including thickening, solar elastosis, and resultant pigmentary irregularities. Carcinogenic effects lead to actinic keratoses, basal and squamous cell cancers, and, less directly, to melanomas. For more information, visit Medscape’s Skin Cancer Resource Center.  

Scarring from trauma or acne contributes to an irregular skin surface. True skin laxity in the form of brow ptosis, eyelid bags, jowls and loss of neckline, ear lobule elongation, nasal tip drop, upper lip thinning, and other manifestations are currently treated surgically with facial rejuvenation procedures (eg, face lift, brow lift, rhinoplasty, lip augmentation). Conversely, these procedures do not help skin textural damage. Fine lines, pigmentary irregularities over a broad area, and aging skin are treated with peeling using either chemical or mechanical means.

A discussion of mechanical peeling is warranted for thoroughness. Lasers largely are used for skin ablation, with the carbon dioxide ultrapulsed laser currently used most often. The erbium:YAG laser is used more for superficial resurfacing when little tightening and superficial depth of peel are required. Many surgeons still use dermabrasion. The lack of control and lack of ability to resurface evenly have resulted in the supplantation of this technique by those already discussed. Microdermabrasion is currently a popular technique because no downtime or discomfort is associated with the procedure. Medical devices tend to have stronger suction, and more abrasive crystals are used, while spa and lay devices tend to be gentler, with less overall effect but increased safety. In general, mechanical abrasion tends to improve scarring more than chemical peeling agents given similar depth of penetration.

Chemical peeling agents are extremely varied, particularly among lay peelers. A great deal of medical and lay "magic" and superstition exist regarding peels and peeling agents. For example, a widely held belief for more than 30 years stated that a stronger phenol concentration used in a deep phenol peel resulted in more superficial depth. This largely has been disproved recently. An excellent series of reviews of phenol peels by Hetter was published in 2000; the reader is referred to this series, cited in the Bibliography, for more information.^4,5,6

Frequency

Chemical peeling is performed extremely frequently. Considering that alpha-hydroxy acid (AHA) exfoliants are currently found in many cosmetic products, peeling is essentially performed with each application of makeup or skin care. Peeling to depth continues to be a popular and excellent means of achieving textural skin improvement. Hundreds of thousands and perhaps more than 1 million phenol peels have been performed in the United States during the last 40 years.

The frequency of aging skin and contributing factors such as smoking, pollution, rampant oxidants of skin molecules, and weather are self-explanatory and are discussed further in Etiology.

A note must be added regarding cutaneous malignancy. The skin is by far the organ most commonly affected by cancer; 1 in 5 people develops skin cancer. More than 1 million cases of skin cancer occurred in the United States in 1997. One half of cancers of the body are skin cancers. Although common skin cancers (ie, basal cell, squamous cell) tend to be localized and nonmetastatic, melanoma incidence doubled from 1973-1991. Of the 8,500 skin cancer deaths in the United States in 1991, melanoma accounted for 6 in 7 deaths.

Etiology

When not compounded by extraneous factors, skin aging basically is the process of atrophy. Loss of subcutaneous tissue is the most obvious and recognizable sign of aging; however, skin, skin appendages, and cutaneous blood supply also atrophy with age. Both the epidermis and dermis thin, and cutaneous strength and elasticity are lost. Dermal-epidermal adherence afforded by rete pegs is lost, and blistering or superficial epidermal loss commonly occurs with aged skin. Overall thinning and loss of integrity and wall strength of the cutaneous vasculature cause easy bruising.

Environmental damage to skin often is explained incorrectly in the literature because of confusion between the short-term and long-term changes that occur. Initially, as with most damage to the human body, the response is inflammatory. This tends to subside rather quickly in the skin, but continuous damage can result in prolonged inflammatory responses. Although postinflammatory hyperpigmentation is often considered a limited medical condition, most individuals express it to some extent, and prolonged exposure to damaging environmental factors results in tanning and prolonged hyperpigmentation. The increased volume of skin from inflammation tends to be transient and caused by increased water volume from increased proteoglycans and glycosaminoglycans.

The true long-term damage to skin from environmental stresses is a decrease in the water volume and increase in damaged cutaneous proteins. In particular, the elastic fibers tend to form tangled masses of nonelastic elastin remnants. This leads to increased volume of skin without functional elements. The solar elastosis or heliosis that is observed histologically is the end stage of this damage. In much the same manner that scarring or fibrosis is observed as the end stage of renal or hepatic disease, scarring and remnants of proteinaceous elements tend to be the end stage of cutaneous disease. Although contracture is present, the general trend in environmental damage of the skin is toward increased thickness, especially of the dermis. This thickening is with nonelastic and structurally weak skin. Sun damage, especially from UV-A wavelengths, causes ionization and oxidation of dermal elements and genetic information, resulting in premalignant and malignant skin lesions.

Many years of acne (both cystic and rosacea) increase the blood flow to skin and tend to hypertrophy the basic elements. Scar tissue also deposits and can contract, leading to uneven skin surfaces. True cysts and sinus tracts commonly result, and ice pick lesions usually are the visible manifestations of these processes.

Pathophysiology

The mechanism of action of peeling agents is relatively straightforward. Stronger agents such as phenol (with various additives such as croton oil and glycerin) and trichloroacetic acid (TCA) produce a chemical necrosis of the skin to variable depths, depending on numerous controlled and uncontrolled variables. The weaker agents (eg, AHAs) change the pH sufficiently to cause a superficial shock to the cells and, depending on many variables, cell injury or death. When used with a moisturizer, the acid acts simply to cause cellular and intercellular swelling and plumping, leading to transient increase in cell and matrix size and lessening of fine lines and rhytides. Sequential treatments lead to exfoliation and a smoother complexion. Continued irritation can lead to many of the same effects of tretinoin or retinoid treatment (ie, increased thickness of dermis, increased blood flow to skin).

The phenol peel deserves special consideration. The Baker formula published in 1962 is as follows: phenol USP 88% 3 cm³ 49%; distilled water 2 cm³ 44%; croton oil 3 drops 2.1% (correct percent if 1 gutta = 27 drops/cm³); and Septisol 8 drops 4.5%.³

The following beliefs remain commonly held about the formula:

1. Phenol was the only active ingredient.
2. Lower concentrations of phenol penetrate deeper than higher concentrations. This was believed to be due to the denaturation of superficial proteins with higher concentrations leading to nonpermeability of the remainder of the solution.
3. Lower concentrations are more dangerous.
4. Septisol (a detergent or surface tension–lowering agent) causes deeper penetration.
5. Croton oil is present only as an irritant.

Clinicians now know that phenol actually peels deeper in higher concentrations. Septisol causes deeper penetration of phenol and a deeper peel. Croton oil (especially the toxic fraction solubilized in phenol) causes a deeper peel.

Other factors that affect the depth of peel include the presence of skin surface oils and dirt; skin water content; temperature of the room, skin, and solution; humidity of the air; length of time the solution is left in contact with the skin; occlusion or nonocclusion; batch of croton oil; thickness of epidermis and dermis; and presence of hyperkeratotic lesions. It is evident why laser resurfacing largely has supplanted phenol peels as a predictable means of deeply removing layers of skin.

Several superficial peels are not equal in result to one deeper peel. Determine the depth of the peel by the severity of the condition being treated; also consider the length of time that a patient will allow for recovery. A deeper peel by any method results in a relatively longer period of redness and inflammation.

Presentation

Aging faces are common to all and recognized as such. Distinguish between textural skin damage treatable by resurfacing or skin rejuvenation (see Images 1-15) and actual ptosis or falling of major structures treatable by surgical interventions (Images 3-10).

Indications

The indications for a chemical peel, since it is largely a cosmetic procedure, depend on the patient's tolerances and wishes for correcting skin textural problems. Many individuals do not wish to improve skin texture despite severe problems, and others desire marked improvement in relatively minor problem areas. Treatments vary with the severity of the condition and the wishes of the patient. Temper these wishes with information on what is possible and what is desirable for the patient in terms of treatment. Approach each patient truthfully, discussing possibilities, risks, benefits, and alternatives.

The ideal candidate has minimal sag or severe skin excess but many fine lines and rhytides. Patients with fair complexions are better suited to peels primarily because of possible postinflammatory hyperpigmentation in other skin colors. These long-term concerns can largely be circumvented with proper pretreatment and posttreatment using bleaching agents. The hypopigmentation commonly observed after deep chemical and laser peels generally occurs in whites and can be avoided with a more superficial peel or by peeling adjacent areas lightly to blend the areas. If a deep peel is necessary, discussing the likely probability of hypopigmentation with the patient is best to ensure that when it occurs it is an acceptable result.

A noted decrease in the incidence of superficial skin cancers and actinic keratoses occurs after resurfacing procedures. Consider a deep full facial resurfacing procedure for individuals with multiple lesions and a splotchy complexion after treatment with liquid nitrogen or dry ice. An alternative treatment is 5-fluorouracil, but it is tolerated poorly by many patients because of the length of time for treatment and healing. This is particularly true on the face. True skin cancers and invasive skin cancers are treated surgically; perform a biopsy on concerning lesions prior to resurfacing.

Relevant Anatomy

See Surgical Therapy.

Contraindications

Contraindications to chemical peeling include documented hypersensitivity to the peeling agent, any of the peel components, or any sedatives used. The procedure also is contraindicated in the presence of facial cancers, with an absolute contraindication in a patient with a facial melanoma or a skin condition such as pemphigus.

Chemical and laser peels are not treatments for all skin cancers. Find and remove these prior to treatment. (For more information on the treatment of skin cancer, visit Medscape’s Skin Cancer Resource Center.) Conversely, carcinoma in situ and actinic keratoses are well treated with deep chemical and laser peels.

Some have stated that chemical peels and laser peels are not useful in individuals who are not white; however, once postinflammatory hyperpigmentation is controlled, few reasons exist not to perform such procedures (see Images 1-10).

Deep phenol peels over extensive areas with large amounts of phenol absorption can lead to fatal cardiac arrhythmias. Monitoring is necessary during panfacial procedures, with attention to small areas (usually one fourth) of the face at a time. Therefore, consider cardiac arrhythmic potential a contraindication to the procedure.

• Search for CME/CE on This Topic »

• Skin Resurfacing - Chemical Peels (Otolaryngology and Facial Plastic Surgery)
• Skin Resurfacing (Otolaryngology and Facial Plastic Surgery)
• Skin Resurfacing, Dermabrasion (Plastic Surgery)
• Facial Analysis for Skin Resurfacing (Otolaryngology and Facial Plastic Surgery)

• Fractional Ablative CO2 Lasers Offer Periorbital Tightening With Brow Lift

• The Asian Dermatologic Patient: Review of Common Pigmentary Disorders and Cutaneous Diseases
• Ancillary Services in Primary Care
• Dermatologic Conditions in Men of African Ancestry