CA - Derm Procedures

can melanoma spread from biopsy?

no

local anethesia

reversible blockade of nerves to lose pain sensation

topical and/or direct infiltration

amides or esters

amides

local anesthetics that are longer acting and metabolized by liver enzymes and excrete in urine

medications with multiple "I"s - lidocaine, prilocaine

esters

short acting local anesthetic metabolized in plasma and tissue fluids excreted in urine

benzocaine, procaine, cocaine

what is often aded to lidocaine & why?

epinephrine is added to increase duration of action, vasoconstriction, reduces systemic absorption and shortens onset of action

this can cause side effects and is contraindicated in some conditions

lidocaine injection

slow, angle ~45 degrees to aim for junction of dermis and subcutaneous where nerve fibers are

types of biopsies

shave, saucerization, punch, incisional or excisional

saucerization bx

excisional; deep shave; scoop shave often with derma blade

removes lesion in entirety, extends into dermis and provides clear 1-2mm margins

quick, easy, inexpensive

can be used for atypical nevi

are skin biopsies sterile?

mostly "clean" not sterile

what determines type of skin bx you'll use?

experience, time, resources

pt factors - bleeding, scaring, care

type of lesion

cosmesis

shave biopsy uses

for elevated lesions, areas of tension and locations where hypertrophic scars are common

superficial or deep

not for dermal lesions, possible melanoma/atypical nevi

caution with bleeders and blood thinners

punch biopsy

incisional or excisional bx for flat or elevated lesions that allows for depth, good cosmesis

sutured closure

many sizes (4mm max on face or ears)

gold standard bx for melanoma

excisional bx

excisional biopsy

removes entire lesion with margins

oriented along relaxed skin tension lines; extremities: vertical orientation to preserve lymphatic system

incisional bx

often used for large lesions on face (lentigo maligna) - often a punch bx >3mm out of larger lesion or 15 blade ellipse

wounds should be closed within how many hours of injury?

within 8 hours to minimize infection and scarring

highly vascular wounds can be closed within 24 hrs when cosmetic appearance is important consideration

where are absorbable sutures used?

oral cavity, GU

disintegrate by enzymatic breakdown or hydrolysis

types of non-absorbable sutures

nylon - high tensile strength, low reactivity

silk - low tensile strength and high reactivity

forceps

non-locking grasping instrument used by assisting hand (left hand), tips point down and helf like pencil

needleholders

held in right hand

controlled opening and closing locking mechanism

how should skin edges be when suturing?

everted

when suturing, how should needle enter skin?

90 degree angle

simple interrupted sutures

traumatic or atraumatic wounds

good cosmetic results

basic suture stitch

mattress sutures

vertical or horizontal sutures to promote wound edge eversion - allows for closure under tension

contraindications for wound closure

foreign body (consider loose closure), delayed presentation, injury of deep structures, uncontrolled bleeding

risks/complications of wound closure

infection, scar, keloid, loss of function/structure, poor cosmesis, wound dehiscence, tetanus

langer lines

lines of cleavage

wounds parallel to these lines will heal well; perpendicular wound may gape

clean wound

incision made during surgical procedure with aseptic technique <2% infection risk

(note: no GI, respiratory or GU spillage)

clean-contaminated wound

clean but with GI, respiratory or GU involvement

contaminated wound

surgical wound with gross spillage (bile, stool, etc) and traumatic wounds

infected wound

established infection prior to wound (abscess) or heavily contaminated wounds

primary intention

all layers closed - best chance for minimal scarring

secondary intention

deep layers closed, superficial layers left open to granulate from outside in - use for signifiant tissue loss, infection, skin tear

large scar and prolonged hearing

third intention or delayed primary closure

deep layers closed, superficial layers left open for reassessment at day 4/5 used for contaminated wounds

if clean with granulation tissue -> irrigate and close; infected -> leave open

tetanus vaccine

should be within 5 years - if unsure its ok to give it

tetanus prone wounds

>6hrs, >1cm depth, stellate or avulsion configuration, devitalized tissue, contamination, GSW, puncture or crush, burn or frostbite association

cutting needle

3 cutting surface - 2 lateral and 1 inner concave curve

used for skin

reverse cutting needle

3 cutting edges, 2 lateral, 1 outer concave curve

used for tough tissue - ligament

taper needle

circumferentially rounded - used for delicate tissue

where are staples often used?

scalp

what is used to clean the wound edge?

betadine, chlorhexidine

straight, full thickness wounds (not gaping or deep) - suture type?

simple interrupted sutures

vertical mattress sutures

far-far / near-near

for deep wounds

horizontal mattress sutures

start on vascular side and exit on less vascular side

for deep, gaping or flap-like wounds

how often to sutures stay in?

location dependent, 5-14 days

shorter duration - scalp, face, ear 5-7 days

extremity, hand 7-10 days; chest/abdomen 8-10 days

longer duration: back, fingertips (10-12), foot (10-14)

smaller suture number (such as 3-0) indicates what size suture?

smaller number = larger size