Deep Chemical Peeling
Gary D. Monheit, M.D.
Associate Professor
Department of Dermatology
University of Alabama at Birmingham
Birmingham, Alabama

Levels of resurfacing reflect depth of skin destruction, vaporization and/or inflammation as performed by chemicals, laser or dermabrasion. Classifying the degree of photoaging skin allows the physician to determine which of his patients require more extensive or deeper resurfacing with each of the modalities. The Glogau system grades photoaging from I to IV, based on intensity and severity of wrinkles. It will guide the physician to the depth of damage to be corrected. The depth of chemical peel penetration has been classified as superficial, medium depth and deep as to level of histologic destruction. Superficial is destructive of partial or complete epidermis; medium depth implies epidermal destruction with the papillary dermis while deep chemical peeling implies inflammation and/or destruction to the mid reticular dermis. Deep chemical peeling is usually reserved for photoaging skin of Glogau III or IV or those with extensive wrinkling and dermal change. (Table I) (Fig 1)

Evaluation of the degree and quantity of wrinkles will direct the physician to the proper level of destruction to correct the condition with minimal morbidity and maximal safety. Deep chemical peeling thus should be reserved for the more severe form of photoaging skin. This is characterized by deep facial rhytids, perioral rhagads, periocular wrinkles and crow’s feet, leathery skin texture with deep creasescreasy skin and loss of elasticity. (Table II) Correction of this same dermal degeneration of collagen and elastic tissue requires destruction of skin to through the mid reticular dermis.3 (Fig 2)

Deep chemical peeling leads to the production of new collagen and ground substance down to a level in proportion to the depth of the peel. Facial skin will rejuvenate itself when damaged to the upper and mid reticular dermis. Injury below that level, though, will produce parallel collagen only with a loss of pilosebaceous apparatus, pigmentation and fine rhytides. This results in the complications of deep peeling – loss of natural skin texture, hypopigmentation and even contractile scar tissue. (Fig 3) It is thus important for the physician to use chemicals with the utmost care as the line of therapeutic efficacy runs very close to over-treatment and complications.

Deep peeling entails the use of either Trichloracetic Acid in concentrations above 50% or phenol-containing preparation. Both chemicals produce protein denaturation of epidermis and dermis with surface characteristics of keratocoagulation. This reaction produces the visual biologic reaction of frosting or an intense whitening of the skin surface. With TCA, the rate of onset and intensity of frosting is dependent on the concentration and quantity applied. TCA above 50% has an erratic and unpredictable level of penetration creating a significant risk for scarring and other complications. The resultant frosting can progress too quickly for the physician to control its safe penetration reliably. For this reason, TCA is not recommended for deep chemical peeling. Thus, solutions containing phenol remain the agents of choice for deep chemical peeling.

The application of pure, undiluted 88% phenol to the skin causes rapid and complete coagulation of epidermal keratin protein and is thought to produce a partial blockade for further chemical penetration. Thus, pure phenol can only penetrate to a medium depth level and is rarely used in chemical peeling because its limited penetration produces an ineffectual peel. The mixtures of phenol thus remain the available chemical solutions for deep chemical peels. There are a number of extemporaneous formulations of phenol, water and other agents but the most reliable and longest used formula is the Baker-Gordon phenol peel.

The Baker-Gordon peel utilizes phenol in a formulation that allows deeper penetration of the chemical reaction into the dermis than full strength phenol. The solution consists of:
1. Septisol, (Vestal Laboratories, St. Louis, MO), a detergent, which solubilizes the other agents and breaks the lipid barrier
2. Croton Oil, a vesicant epidermolytic agent that enhances phenol absorption
3. Phenol, the active keratolytic agent, and
4. Water, which reduces the phenolic concentration to 50 or 55% (Table III)

The more dilute solution – 50% - has greater penetration and thus peel potency than the full strength 88% straight phenol preparation. As one dilutes even further with water, the degree of penetration and potency is reduced.

The Baker-Gordon formula is well documented in the scientific literature with animal models; histology, clinical studies and long term follow up as to its efficacy and predictable results. Regeneration of new collagen with resultant skin rejuvenation has been well documented with long-term follow up studies of greater than 20 years. For this reason, the formula has stood the test of time unchanged over these 40 years.

Recent investigations by Hetter into varying the concentrations of both phenol and croton oil have suggested that the efficacy of the reaction is dependent on more than phenol concentration alone. Altering the concentration of croton oil can produce a less penetrant peel and thus reduce the risk of hypopigmentation and “alabaster skin.” (Fig 4) These and other modifications of the present Baker-Gordon formula are currently under investigation.

Phenol is a potential systemic toxin with significant systemic absorption. It is a potential cardio toxin and undergoes hepatic and renal elimination. Serum levels of phenol can rise to dangerous levels with overuse or overzealous application. For this reason, all patients undergoing full-face phenol peeling should have a complete physical examination including EKG, complete blood count with liver and renal function determinations. Any patient who has a history of cardiac arrhythmia and who is taking a medication known to precipitate arrhythmias should not undergo a full face Baker-Gordon phenol peel.

All patients undergoing full face phenol peels should be monitored and given one liter of 0.9% NACI or lactated Ringer solution prior to this peel to initiate renal diuresis dieresis. An additional liter of fluid should be administered during the peel to further eliminate systemically absorbed phenol and lower the serum concentration.

A full face Baker-Gordon phenol peel is conducted in 1-½ hours with a 15-minute waiting period between each cosmetic unit. This will protect the patient from excessive phenol absorption and elevated serum levels. Continuous electrocardiography, pulse oxymmetry, and blood pressure monitoring are mandatory during the entire operative period. If any cardiac arrhythmia occurs, the procedure should be abruptly stopped, toxicity evaluated and the arrhythmia treated. Treatment should include O2 supplementation and anti-arrhythmias.

The day of the procedure, the patient may shave and cleanse, have a light breakfast, but may not apply cosmetics. The skin is marked while the patient is seated to outline the borders of the facial peel. Although deep resurfacing procedures can be accomplished entirely with nerve blocks and anxiolytic sedatives, some patients require deeper conscious sedation during the procedure. The peel solution should be mixed fresh daily for each patient. The formula should be followed carefully and ingredients verified by a second assistant. The accuracy of the formulation is an important determining factor in the efficacy and safety of the peel. The solution is an emulsion and must be stirred prior to application. (Fig 5)

Prior to the application of the peeling solution, the surgeon must vigorously cleanse or debride the skin surface to remove residual oils, debris and excess stratum corneum. The face is initially scrubbed with 4 x 4 gauze pads containing 0.25% Ingrasan (Septisol, Vistal Laboratories, St. Louis, Missouri), then rinsed with water and dried. Acetone is then applied as a defatting and degreasing agent with moist gauze pads. A thorough cleansing and degreasing will ensure equal penetration of peel solution over the face and thus an even peel.

The peel solution is applied with cotton tip applicators, one cosmetic unit at a time. The emulsion is gently stirred and the cotton tip is dipped with a conservative amount of peeling agent. It is applied evenly over the cosmetic unit. (Fig 6) Frosting is immediate and only unfrosted areas are retreated. (Fig 7) The frosting fades rapidly to a gray brawny color and texture. The peel solution is applied over the jawline and worked into the hairline and eyebrows to give an even transition. Using the wood portion of the cotton tip, peel solution is worked into deeper rhytids and perioral rhagades. Aesthetic units are sequentially treated from forehead to cheeks, chin, nose, lips and finally the periorbital skin. Care is taken to protect the globe from peel solution. If there is accidental peel solution spillage, it should be flushed out with mineral oil rather than saline. (Fig 8)

The Peel
After the peel application, a mild emollient can be applied or the tapping procedure is immediately begun. Occlusion of the peeling solution with tape is thought to increase its penetration and extend the injury pattern. This is particularly useful for the deeply lined “weather-beaten” faces but should be done only by the most experienced physicians. The deeper penetration of taping may be responsible for the hypopigmentation and alabaster appearance proceeded in some patients. White waterproof tape (3-M Corporation) is layered by overlapping strips over the entire face. The taped mask is removed in 24 hours. The underlying necrotic tissue is liquefied making tape removal easier, but some patients require anesthesia for this second procedure.

The unoccluded technique as promoted by McCollough, relies on a greater amount of peel solution applied to obtain a similar level of tissue rejuvenation. Careful post-operative cleansing and debridement is necessary to remove the necrotic tissue in the untapped peel. (Fig 9) The incidence of hypopigmentation and “plastic skin appearance” is less with this modification.

The patient experiences an immediate burning sensation as the peel solution is applied but subsides within 20-30 minutes. It returns as a deep burning sensation over the next 6-8 hours. It is for this reason the patient receives pain medication post-operatively and would benefit from local marcaine nerve blocks. Systemic steroids (40 mg. Triamcinolone acetamide IM) are routinely given to reduce inflammation and antiviral agents are taken for 2 weeks.

The peel will take 10-14 days for reepithelialization and post-operative care is labor intensive. The patient is to soak the denuded facial skin with ¼% acetic acid compresses (1 tsp white vinegar with 1 pt warm water) to debride and cleanse 4 times a day. The acetic acid solution is antibacterial, especially against gram-negative organisms, and is aseptic as its mild acidity debrides necrotic tissue. Occlusive ointments are applied after the soaks to prevent scabbing and crusting and for patient’s comfort. (Fig 10)

Frequent post-operative visits are necessary to recognize healing problems early on and thus prevent complications. Difficulties such as post-operative bacterial or viral infection can be recognized and treated appropriately. If left untreated, it will progress to delayed wound healing with a potential for scarring.

As one may consider, patient selection is of critical importance for the deep peel. (Fig 11) The patient undergoing this procedure must be fully informed and willing to accept the inherent risk of complications, the degree of morbidity, as well as a realistic understanding of results. Excessively loose skin of the face and eyelids will not improve with peeling and will only respond to surgery. Similarly, deep grooves, cheek and tear trough “hollows” cannot be fixed by peeling but respond to filling agents. The adjunct of Botox pre-operatively will help improve the dynamic wrinkles of the forehead, glabella and crow’s feet. The Baker’s phenol peel will produce excellent results on advanced photoaging skin with rhytides and rhagades in the perioral and periorbital area. (Fig 12) Long lasting results have been documented by histology over 15 years. Comparable, if not better results than CO2 laser resurfacing in the perioral area have been demonstrated. (Fig 13)

Many patients require deep peeling only in specific cosmetic units such as the perioral and periorbital area. A combination procedure will reduce the operative morbidity by using Baker’s phenol on the perioral and periorbital skin and a medium depth peel – such as the Monheit version Jessner’s 35% TCA – on the isolated cosmetic units so that there will not be pseudo-hypopigmentation in those areas. (Fig 14) This combination will reduce the need for general anesthesia as well as the post-operative morbidity.

In the age of laser resurfacing, the deep chemical peel still offers some unique advantages in the severely photoaged skin. The results appear more complete and longer lasting. It is, thus, to the cosmetic surgeon’s advantage to have this procedure in his armamentarium for those specific patients who need this degree of resurfacing.