Choosing the Correct Peel for the Appropriate Patient

Introduction

Chemical peels are a method of resurfacing the skin to address a variety of skin conditions. The benefits of understanding the peel–tissue interaction gives the physician the ability to selectively resurface various parts of the skin, thus allowing for control and artistry in the resurfacing process. By inducing a controlled wound to the skin, chemical peels can resurface part or all of the epidermis (very superficial and superficial peels), the papillary dermis (medium-depth peels), even down to the level of the upper or mid-reticular dermis (deep peels). By forcing turnover of skin cells, peels can improve photodamage, rhytides, pigmentation abnormalities, and scarring.

Chemical peels are divided into four categories depending upon the depth of the wound created by the peel (see Chapter 4, Chapter 5, Chapter 6, Chapter 7, Chapter 8 ). Very superficial peels only penetrate through the stratum corneum and the uppermost portions of the epidermis. Superficial chemical peels penetrate the epidermis but not more than the basal layer of the epidermis. Medium-depth peels penetrate the entire epidermis plus the papillary dermis. Deep chemical peels create a wound to the level of the upper and mid-reticular dermis.

Each category of peels addresses a different aspect of photodamage and pigmentary abnormality. Healing time and complications vary among the different categories of peels as well, with some peels being more appropriate for certain skin types. Therefore, to maximize the benefits of a peel for a patient and to minimize adverse effects, it is important to choose which, if any, peel is appropriate for each patient.

Evaluation of the Patient

When evaluating a patient for a peel, an extensive history should be taken. The patient should be questioned regarding a history and frequency of herpes simplex virus (HSV) infection, human immunodeficiency virus (HIV) status (more so, viral load), keloid formation, previous x-ray therapy of the skin, nicotine use, oral isotretinoin use, and a history of a previous facelift or browlift.

Patients with a history of frequent HSV infections (more than 1 every 6 months) should be treated prophylactically to prevent an outbreak of herpes during the healing process. This is most important during medium-depth and deep peels. All patients having a medium-depth to deep peel should receive HSV prophylaxis with the dose adjusted so that it is higher in patients prone to more than one HSV breakthrough every 6 to 12 months. Typically patients having a medium-depth or deep peel are started on 500 mg valacyclovir twice a day for 7 to 14 days starting the day before the procedure. If they are at risk for HSV, the dose is increased to 1000 mg twice a day. If an HSV or varicella zoster virus (VZV) breakthrough is suspected during the healing process, the dose is increased to 1000 mg three times a day for 14 days.

Patients with detectable viral loads of HIV are poor candidates for a medium-depth or deep peel, because their immunocompromised state delays wound healing and increases the risk of wound infection and subsequent scarring. Transplant patients and patients on immunosuppressive medications for autoimmune diseases are similarly at risk for infection and poor wound healing.

The biggest controversy is the concern over timing of skin resurfacing in patients who have just completed isotretinoin treatment. The previous recommendation of waiting 6 to 12 months after isotretinoin use to have a chemical peel may have been overexaggerated. Isotretinoin does impair wound healing, but there is growing evidence that resurfacing patients with peels and lasers may be safe as early as 3 months after the medication is completed.

Although peels can be performed simultaneously with surgical procedures, the timing of skin resurfacing changes for patients who have had recent surgery in the same area. The safe window for resurfacing is either the same day as surgery or 6 to 12 months after a facelift or browlift procedure. The extensive undermining during facelifts and browlifts compromise the skin’s lymphatic drainage, so it is best to wait 6 to 12 months to reduce the risk for prolonged postoperative edema.

Superficial x-ray therapy of the face (used many decades ago to treat acne) destroys the pilosebaceous units, which, in turn, leads to delayed reepithelialization, and nicotine use decreases the blood supply to the skin and delays wound healing. Both of these underlying factors can result in an increased risk of scarring.

The physician should also perform a physical examination and pay particular attention to the patient’s skin type and degree of photodamage. Skin type can be classified using the Obagi Skin Classification System ( Table 2.1 ). This skin classification system can be used to objectively assess the patient’s skin and is an important tool for choosing the appropriate peel. This classification system incorporates more information than the traditional Fitzpatrick skin type or Glogau scales did. The five assessments are skin color, oiliness, thickness, laxity, and fragility ( Figs. 2.1–2.5 ).