Sun protection and solar damage Flashcards
Explain sun damage
Accumulates over time
Lifetime exposure = risk
UV = sunburn, ageing, cataracts, immunosuppression, skin cancer.
Compare UVA and UVB
UVA - 320-400nm= most UV light. Penetrates skin deeper than UVB (goes into superficial dermis). Causes indirect DNA damage and photoaging. Less efficiently filtered by sunscreen and can penetrate window glass. Tanning beds. Cause cancer.
UVB- 280-320nm. Intensity depends on season and time. Main cause of sunburn. Mostly absorbed by epidermis. Direct DNA damage.
Signs and symptoms of sunburn
Painful erythema 2-6 hrs post exposure
Maximum severity at 24 hrs
Severe= malaise, fever, N/V
Resolution w/ peeling over 4-7 days
Types of skin cancer
Basal cell carcinoma
Squamous cell carcinoma
Melanoma (most dangerous)
2/3 Australians diagnosed w/ skin cancer by 70 yrs.
Discuss basal cell carcinoma
Mostly on head and neck
Rare metastasis but can cause localised damage
Small, shiny, firm, clear-pink, raised growth
Over time, visible blood vessels open and scab
Slow growing tumours
Biopsy needed
Explain squamous cell carcinoma
Occurs on areas heavily exposed to sun (head, back of hands, neck, limbs)
Tender lesion that appears suddenly and grows rapidly/over weeks-months
Thick, scaly, irregular appearance, raised, firm (wart-like)
Damaged skin
Basal cell carcinoma treatment
First- Treat w/ surgical removal except superficial
Superficial BCC = cryotherapy, PDT, and topical imiquimod
Advanced BCC= vismodegib (150mg od)
SCC treatment
First- surgical treatment w/ a 3-5mm margin
Radiotherapy if no surgery
Explain melanoma
Australia has highest incidence in world
Malignant tumours derived from melanocyte (arise within a mole or freckle)
Several different types and classifications
Melanoma treatment
Surgical removal
prevention
Melanoma warning signs
New or changing mole
Prominent and pigmented
Stands out from other moles
Rapidly growing nodule
Particular concern
Typical presentation
ABCDE of melanoma detection
Asymmetry - not mirror image
Border - usually irregular
Colour - number of colours through it
Diameter - growing and changing in diameter and size
Evolution - changing and evolving
Ingredients in sunscreen
Organic chemicals- absorbing agent
- salicylate, etc
allergic contact dermatitis possible
Inorganic substances- physical blockers
Zinc oxide, titanium dioxide
How to apply sunscreen
Apply to exposed sites 15-30 mins before going outside, or when UV >3
Use generous amount 30-40ml for adult
Reapply every 2 hrs and after activity
Last 2-3 yrs if stored below 25c
Explain SPF
Sun Protection Factor = how well sunscreen protects against sunburn. Based on UVB. Time for mild erythemal dose (MED) burn to appear with sunscreen / without sunscreen.
SPF50+ must be >60
Sunburn treatment
Limited data for NSAIDs, oral/topical corticosteroids reducing severity of burn
Cool compress for symptoms
Water intake for dehydration
Anaesthetic spray (paxyl, solarcaine) relieve pain
After sun cream/gels
Cooling gels - solosite, solugel
Aloe vera limited evidence
Actinic keratosis treatment
Fluorouracil cream - Apply od or bd for 2-4 weeks (face) or 3 weeks for arms and legs
Imiquimod 5% cream
Diclofenac 3% gel - bd for 60-90 days
Methyl aminolevulinate - 1x session of photodynamic therapy
patch or cream and then PDT
Explain fluorouracil cream
Interfers w/ DNA synthesis
Continue treatment until inflammatory response
Normal to redden, peel, or crack.
3-4 weeks or longer
Face responds faster
Thin layer to area using non-metal applicator or rubber gloves
Avoid contact w/ eyes, nostrils and mouth
Explain imiquimod 5% cream
Enhances immune response
Apply before bed - leave on for 6-10 hrs and then wash off with mild soap and water
Wash with mild soap and water and dry before applying
Wash hands before and after use
Avoid bathing/showering after application
Protect area from sunlight
Avoid eyes, lips and nostrils
Explain diclofenac 3% gel
+ hyaluronic acid 2.5%
Block COX2, reduce angiogenesis and cellular proliferation
Avoid eyes and mouth
Do not cover w/ occlusive dressing
Protect area from sunlight
Take up to 30 days after finishing treatment for complete healing of lesions
Not interchangeable w/ voltaren
Potential systemic absorption
Lifestyle changes
Slip - clothes
Slop - SPF30 on dry skin 20 mins before going outside
Slap - hat (not cap/visor)
Seek - shade (reflection of sun)
Slide - sunglasses
Caring for skin after cryotherapy
Cryotherapy treats actinic keratosis
Freeze skin to produce destruction of lesion
Day 1 after- leave blisters alone or lance w/ sterile needle
Day 2/3- let weep open, wash with soap and water, cover with dressing if excessive
Day 3/4- let scab heal
