05 May 2009

Dermatologic Surgery



Dermatologic Surgery
Presentation lecture by:Kristy P. Gilbert, D.O.

Introduction
* Derm surgery increasing in complexity
* Aesthetic and Laser procedures
* Plastic surgery – blepharoplasty, facelifts, liposuction
* Mohs micrographic surgery
* Increasing emphasis on patient safety, documentation, and accreditation.

Basics: Pre-Op Evaluation
* Drug Allergies
* Meds: Coumadin, Plavix, ASA.
* Pacemaker? Defibrillator?
* MVP, Endocarditis, Prosthetics?
* Informed Consent, photographic consent, risks v. benefits and options must all be discussed & signed
* OTC and Herbals…..

Past medical history

* Factors that will affect wound healing
* Prophylactic antibiotics
* Risks for scarring
* Risks for bleeding

Factors that will affect wound healing
* Advanced age
* Nutritional status
* Diabetes
* Immunosuppressive drugs
* Smoking
* Critically ill patients, HIV
* Atherosclerosis, PVD

Prophylactic Antibiotics
* Contaminated or “dirty” wounds benefit, not clean wounds
* Indications
* ear, nose mouth, hand foot, axilla, genitalia (“dirty” areas)
- Artificial Heart Valve
- Artificial Joint Replacement < 6 months
- Past history Endocarditis, Rheumatic Fever
* Mitral Valve Prolapse WITH holosystolic murmur
* Immunocompromised

Antibiotic Prophylaxis:
Risks for scarring
* Location: upper chest, back, shoulders, extremities
* Personal hx scarring: i.e. keloids, hypertrophic scars
* Medications: isotretinoin in past 12 mo. Or Vitamin A or E use

ASA/NSAID containing drugs

* There are about 160 of them
* Most are OTC
* Patients don’t think of these as drugs because they are not prescriptions.

ASA/NSAID containing drugs

* Aspirin
* Irreversibly acetylates platelet COX reducing PG and thromboxane A2 synthesis therefore platelets inhibited for their lifetime (7-10days)
* For this reason, must be D/Ced 7-10 d pre-op
* NSAIDs
- Reversibly inhibit COX therefore less clinical effect
Other drugs affecting platelets

* Production
* Myelosuppressive agents, ethanol, estrogens, thiazides
* Destruction
* Abx: sulfathiazole; quinine, ASA, dig, methyldopa
* Function
- ASA, dipyridamole, ethanol, heparin, NSAIDS, plavix, ticlopidine, herbal supplements

Herbal Supplements that inhibit coagulation….

* MOST COMMON: Fish Oils, Garlic, Gingko, Ginseng, Chinese Herbal/Green Teas, Vitamin E
* Alfalfa, Capsicum, Celery, Chamomile, Dong quai, Fenugreek, Feverfew, Ginger, Horseradish, Huang qui, Kava kava, Licorice, Passionflower, Red Clover.

Local anesthesia
* Ideal properties
* Rapid onset
* Long duration of action
* Lack of toxicity
* Water solubility
* Structure & function
* Aromatic portion= lipophilic= potency
* Amine= hydrophilic= solubility
* Intermediate chain- determines class: i.e. ester, amide AND most importantly- this determines route of excretion and metabolism
* MOA = blocks movement of Na+ influx across membrane thereby blocking depolarization

Local Anesthesia Categories
* Esthers:
* Procaine (novocaine)
* Chloroprocaine (nesacaine)
* Cocaine
* Tetracaine
* Benzocaine
* Amides

-Lidocaine (xylocaine)
* Mepivacaine (carbocaine)
* Prilocaine (citanest)
* Etidocaine(durantest)
* Bupivicaine (marcaine) = the LONGEST acting
* Nupercaine
* Pearl: fears of epinephrine induced necrosis at distal sites (nose, ears, penis, toes, fingertips) are largely unfounded.
* Pitfalls: patients with severe peripheral vascular disease, diabetic angiopathy and Raynaud’s phenomenon may be exceptions to the rule.
* Contraindications to epinephrine in anesthsia:

-severe HTN, pheochromocytoma, HyperTH, severe vascular ds, bradycardia “ABSOLUTE”
-pregnancy, MAO inhibitors, narrow angle glaucoma “RELATIVE”
* Maximum dosage
* Insert needle at a 30 degree angle and slowly retract the needle as you inject the anesthetic. When the tissue blanches you are at the right level.
* Always best to try to avoid too many sticks, if your doing a larger area, each re-stick should be into an area that has already been anesthetised

Pain Control
* Local Anesthesia:
* INJECT SLOWLY: Decreases pain more than warming or adding bicarbonate.
* Distraction techniques useful as well – pinching skin during injection, vibrating pen, etc.
* For pediatric patients, let them sit in the lobby with ELA-Max or EMLA under occlusion for 30 min.- 1 hr. Your eardrums will thank you.

Surgical Cleansers
* Clean Procedures:
* Isopropyl alcohol
o weak antimicrobial
o most commonly used agent for shave biopsies
* Hydrogen peroxide
o no significant antiseptic properties
o not suitable for sterile procedures

Surgical Cleansers: Sterile

* Betadine
o irritating to skin, residual color
o must dry completely to be antimicrobial
o absorbed by premature infants
* Chlorhexidine (Hibiclens)
o keratitis if it gets in the eyes
* Hexachlorophene (pHisoHex)
o not on women or children due to neurotoxicity and teratogenicity

Common Procedures

* Shave Biopsy
* Punch Biopsy
* Excisional Biopsy
* Cryosurgery

Shave biopsy
* Best suited to pedunculated, papular or otherwise elevated lesions but may be used for macular lesions.
* Simple
* Quick
* Satisfactory cosmetic result
* Adequate biopsy tissue for diagnosis
* Sterile #15 blade
* 4x4’s
* Drysol solution
* Sterile Q-tips
* Path container
* Gillette Blue Blade Razor cut in half, bends to follow contour

Shave Biopsy - skin tension
Shave Biopsy - flush w/ surface
Endpoint is “pinpoint bleeding”
Indicates you are at the level of the papillary dermis, minimal scarring

* Stay superficial for minimal scarring.
* Pink atrophic area has a full year to heal.
* Upper chest and back scars no matter what you do.
Punch Biopsy
* Most common use is for skin biopsy
* Can excise small lesions
* Treats acne scars
* Hair transplantation
* May stretch skin perpendicular to skin tension lines to create elliptical defect and avoid “dog ears”
* Sterile OR clean procedure
* 3 or 4 mm punch is standard
* 4x4s, Drysol, Q-tips
* Needle driver, forceps
* Suture
* Path specimen bottle
* Twist punch tool until buried to the hub*
* *Caveat: Have a firm grasp of anatomy and skin thickness in the area you are punching before you punch it.
* Finger tendons, facial and neck structures.
* KEY: do not crush tissue when removing it from the biopsy site.
* Crush artifact makes pathologic interpretation difficult to impossible.
* Some pull it out using the suture needle as this method is atraumatic.


Hemostasis
* Chemical
* Electrical
* Physical

Chemical Hemostasis
* Drysol
* Aluminum Chloride
* Quick, easy, cheap.
* Q-tip application.
* No odor or discoloration.
* Good for superficial biopsy - shave.
* Monsel’s solution.
* 20% ferric subsulfate.
* Cheap, easy to use.
* Risk of tattooing.
* Superficial only!
* Caustic, may destroy connective tissue if sutured into wound.

Electrosurgery
Electrosurgery- definitions

* Electrosurgery- passing high frequency alternating current (AC) thru the tissue
* Electrocautery- electrically heated metal element applied to tissue; transfers heat but does not transfer current thru tissue
* Electrolysis- low direct current (DC) passed thru tissue b/w 2 electrodes; chemical reaction occurs @ one electrode
* Diathermy- the process of heat production and tissue necrosis due to electrosurgery
* Monoterminal= one connection b/w device and pt. (i.e. electrodessication, electrofulgration, epilation, hyfercation)
* Biterminal= 2 contacts b/w device and pt. such as a ground plate (i.e. electrocoagulation, electrosection)

Electrodessication/Electrofulguration

* Electrodessication – tip touches tissue
* Electrofulguration – 1-2mm separation between tip and tissue
* High voltage and low amperage limits depth of destruction
* Monoterminal current – no grounding required

Electro-epilation

* Follicular destruction
* AKA Electrolysis
* Chemical reaction at electrode tip causes production of sodium hydroxide (lye) at the hair root – works without scarring.
* Takes 1 minute per follicle, very slow.
* Largely replaced by laser hair removal.

Electrodessication

* LOW POWER:
* Facial telangiectasias
* Syringomas
* HIGH POWER:
* SK, Skin Tags, VV
* ED&C: BCC & SCC under 2 cm, 2-3 cycles
* Hemostasis during excisional surgery.

Electrosection

* “Cutting Current”, Radio-Frequency Ablation
* Biterminal current produced by vacuum tube is similar in form to radiowaves
* Active electrode is cool
* Tissue disruption occurs in response to the wave at the point of contact.
* Minimal trauma, excellent hemostasis.
* “Custom” attachments: wire loops, balls, needles, scalpels.
* i.e. tx of rhynophyma

THERMAL CAUTERY
Electrosurgery and pacemakers
* Published debate
* Standard of care tends to be use of only electrocautery
* Most modern pacemakers operate in a demand mode, requiring sensing and output circuits which can be interupted by high frequency electrosurgery

Curettage
ED&C
Cryosurgery
Cryosurgery delivery systems
Cryosurgery complications
Classic atrophic hypopigmented cryosurgery scars……
Excisions- margins
Mask Area of Face
Always consider the anatomy!
Branches of the facial nerve
Facial Nerve Damage
Excision: Instruments
Webster Gillies
BROWN ADSON FORCEPS – HEAVY TISSUES
CASTROVIEJO FORCEPS – DELICATE TISSUES
IDEAL FOR FLAPS, CUTTING THICK, LESS DELICATE TISSUE
Absorbable Suture
Non Absorbable Suture
SIMPLE INTERRUPTED
VERTICAL MATTRESS
CORNER STITCH
HORIZONTAL MATTRESS
DEEP SUTURES
RUNNING SUBCUTANEOUS
RUNNING SUBCUTICULAR
Mohs Surgery
Mohs- indications

* Recurrent or persistent tumor
* Anatomic location
* Embryonic fusion planes
* Nasolabial folds
* Columella of nose
* Pre- auricular, post-auricular sulcus
* Conservation of tissue impt.
* eyelids, nose, lips, ears, genitalia
* Size
* >1cm on head
* >2cm on trunk & extremities
* Special considerations
* Very young/ old
* Immunocompromised
* Unusual tumors
* Pt or family anxiety
* Poorly defined borders
* Scar carcinoma
* Major histo indications
* BCC subtypes
* Morpheaform
* Adenoid
* Superficial multifocal
* Perineural
* SCC subtypes
* Poorly differentiated
* Acantholytic
* Perineural
* Basosquamous
* Microcystic Adenexal
* DFSP
* Merkel cell
* Malignant fibrous histiocytoma
* Lentigo maligna
* Rowe et al reviewed literature since 1947
* 5 year recurrence rates primary BCC

General Surgical Complications
* Hematoma –
* usu 24-48 hrs post-op
* no evidence that ASA, NSAID or COUMADIN increases risk of hematoma
* Open and evacuate clot if necessary
* Gentle heat may facilitate reabsorption
* Bleeding
* Intraoperative control imperative
* Post-op: dressings, minimize post-op movement/activities
* ? d/c anticoagulants
* Infection –
* Main contamination period is peri-operative
* Pain, warmth, erythema, swelling, D/C, fever, chills, malaise
* Can culture, Irrigate, daily wound care, abx 7-10 days
* Dehiscence – from infection, trauma, poor surgical technique, excessive movement
* Necrosis – high tension in sutures or wound edges, poor flap design.

Avoiding Surgical Complications
* Aseptic technique
* Meticulous hemostasis
* Wide undermining
* Good surgical planning

Advancement flaps
* Primary movement is straight across the primary defect
* Essentially a large ellipse/ fusiform closure
* Types: O-H, O-T, V-Y, island pedicle
* Locations:

-Unilateral- anywhere
-Bilateral- forehead, eyebrow, upper lip, upper nose, chin
Rotation flaps

* Primary movement is arc-like or rotary
* Tension distributed away from primary defect to secondary defect
* Tension decreased by increasing length
* Recommended locations:
* Scalp, forehead, chin, cheek
Transposition flaps

* Movement of flap results in crossing intervening skin to reach defect
* Tension completely redirected from primary to secondary defect
* Creates larger secondary defect than other flaps
* Good for defects near free margin
Cutaneous Laser Surgery

* Light Amplification by Stimulated Emission of Radiation
* Light limited to one WAVELENGTH
* CHROMOPHORES are substances that preferentially absorb one WAVELENGTH
* Examples: water, Hgb, melanin
* HEAT created = “Selective Thermolysis”

Argon Laser

* Vascular and pigmented lesions
* 488 to 514 nm wavelength
* These are NOT the wavelengths specific to Hgb and melanin, therefore damage to surrounding tissue significant, possibly leading to scarring and hypopigmentation.
* Has fallen out of favor
Flashlamp Pumped Pulsed Dye
Q switched Ruby

Dermatologic Surgery.ppt

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