Disease

Question 1

Skin tearing

Answer 1

1A- edges align and skin or flap not pale
1B- edges can be aligned but skin or flap is pale, dusky or darkened
2A- edge cannot be aligned skin flap is not pale, dusky or darkened
2B- edges cannot be realigned and flap is pale, dusky or darkened
3- skin flap is absent

Question 2

Chemical burns

Answer 2

Classified into mechanisms of action- reduction, oxidation, corrosive agent, protoplasmic poison, vesicants, desiccants

• alkalines - liquefaction of skin- lime, sodium hydroxide, potassium hydroxide
• Acids- hydrofluoric acid, hydrochloric acid, oxalic acid- cause hard dry eschar to form
• organic compound- petroleum distillates- dissolve lipid wall of cell membrane, may also cause renal and liver failure if absorbed

Question 3

Electrical

Answer 3

Low voltage <1000, high voltage >1000, creates crush injury and possible death from ventricular fibrillation or direct damage to heart tissue or resp failure (damage to resp centre in brain or resp muscles). Most likely to travels along deep blood vessels and organs, may not be obvious from outside of body

• direct current (lightening)- likely cause cataracts
• alternating current (house electrics)- cause muscle contractions that prolong contact with current

Complications- cardiac arrest, arrhythmia, metabolic acidosis, myoglobinuria (pigment from muscle damage in urine, may lead to renal failure)

Question 4

Radiation

Answer 4

Sun exposure to radioactive substances

Question 5

Cold injury

Answer 5

Frostbite- As tissue freezes ice crystals form and increase intracellular sodium content

• swelling
• continued exposure=vasoconstriction, increased blood viscosity, leading to infarction and necrosis.

As tissue thaws burning pain begins

Question 6

Inhalation injury

Answer 6

Burnt inside lungs

Question 7

Friction burns

Answer 7

Rope burn, road/grass burn

Question 8

Burn classification

Answer 8

Depth-

• superficial, epidermis, superficial dermis (pink/red)
• partial- superficial (epidermis and papillae of dermis- bright red with moist glistening appearance, blisters, blanch on pressure) and deep partial (epidermis and reticular dermis- pale blotchy red, moist or dry, large blisters. Decrease pain, cap refill is decreased)
• full- epidermis, dermis and epidermal appendages, May extend to subdermal level (fat, muscle, bone) pale, waxy, yellow, brown, mottled, charred, non-blanching. Dry leathery and firm. No pain on light touch
• extent of burn- % of total body surface
• Wallace rule of 9- only suitable for adult- anterior-head/neck=4.5%, arm 4.5%, leg 4.5%, trunk 18%, perineum 1%

Lund and browder burn assessment- paediatrics-adults

Question 9

Burn management

Answer 9

*resuscitative phase-first aid, primary survey
A- airway- spot in mouth, cervical spine precautions
B- breathing- humidified O2, assess for carbon monoxide poisoning using breath test, head of bed 30 degrees and turn every 2 hours to prevent hypostatic pneumonia
C- circulation- cap refill- if less could be hypovolaemia/hypothermia, stop bleeding, elevate burned oedematous limb, cardiac complications if electrical
D- disability/neurological status- LOC- Glascow scale, restlessness
E-exposure/environment- remove jewellery and burned clothing, prevent hypothermia
F-fluid resuscitation- 2x cannula in non burned tissue, take blood cross match, IV fluids, IDC, nasogastric tube if >15% TBSA

Secondary survey- look for other injuries once life threatening managed

• acute wound healing
• starts at diuresis stage
• wound care management, nutritional therapies and measures to control infection, excision and grafting of wound, enteral feeding, pain management
• rehabilitation
• bio-psychosocial adjustment, prevention of contractures and scars.
• physical, vocational, occupational and psychosocial rehabilitation, educate on ROM exercises

Question 10

Burn management

Answer 10

Parkland fluid formula (2-4mls x kg x %TBSA in first 24hrs- 1/2 first 8hrs, then 1/4 next 8hrs, then 1/4 next 8hrs), Chest X-ray, ABG’s, head of bed 30 degrees, turn every 2 hours to prevent hypostatic pneumonia, incentive spirometry, O2 sats, humidified O2, possible intubation, warm room to prevent hypothermia, bronchodilators, art line, IV analgesia as GI absorption reduced

Tetanus prophylaxis to prevent clostridium tetani infection, chlorhexidine wash and topical antibiotic wound dressings- silver

Escarotomy- cut down leg to release pressure (packed with calcium alginate and covered with nanocrystalline for 24hrs)

Surgical debridement- debried till bleeds as tissue then viable

Skin grafts- cultured epithelial autograft (keratinocytes placed on medium containing epidermal growth factor), homograft/allograft (skin from cadavers), heterograft/xenograft (silver nitrate impregnated porcine dermis), bioengineered tissue substitute (biobrane-adheres well and separates once under layer healed. Integra-dermal replacement), split skin grafts (SSG)- epidermis and variable depths of dermis

Graft care- remove exudate, slit blisters and drain, cover with paraffin dressing or nurse open

Physio-chest physio, ROM exercise, reduce positions that cause deformities of skin healing-splints

OT- function and scar management, increase independence, compression wear to reduce hypertrophic scars, scar massage

Dietitian- enteral feeding >20% TSBA and maintaining nutrition

Question 11

Fungal infection

Answer 11

Deematophytoses (ringworm/tinea)- transmit through animal, person contact, inanimate objects

Risk factors- pregnancy, diabetes, immunodeficiency, nutritional deficiency, age

Tinea pedis-feed
Capitis- head
Corporis-body
Versicolour- upper chest/back
Cruris- groin 
Candida albicans-mucous membranes

Treat- antifungal drugs

Question 12

Warts

Answer 12

HPV/ condylomata acumimate (genital/cervical warts), verruca vulgaris (common warts), verruca plans (flat wart forwhead/dorsum hand),

Treat- liquid nitrogen, cryotherapy, acid therapy

Question 13

Herpes zoster

Answer 13

Reactivation of varicellaon dorsal ganglion and corresponding skin dermatomes

Risk factors- age, immunocompromised, Hodgkin’s disease, leukaemia, radiation/chemo, HIV

Complications- post herpatic neuralgia and vision loss

Question 14

Parasites

Answer 14

Pediculosis-lice- live omg blood of host. Have anticoagulant in saliva

Pediculosis corporis- body lice-more common in Homeless, lice live in clothing fibre. Results in skin lesions and pruritus

Pediculosis pubis- pubic lice/crabs- sexual contact or contact with clothing/linen

Pediculosis capitis- Head lice- contact and sharing brushes and hats

Question 15

Scabies

Answer 15

Sarcoptes scabiei- nite burrows into skin and lays eggs that hatch every 3-5days- diagnosed with skin scrapings

Question 16

Contact dermatitis

Answer 16

Hypersensitive reaction- allergen binds to Cartier protein forming an antigen, antigen is processed and carried to T cells which sensitise to antigen

Common causes - soaps, chlorine, cosmetics, fabrics, latex, metals, plants

Question 17

Atopic dermatitis/eczema

Answer 17

Depressed cell-mediated immunity, elevated IgE levels and increase histamine sensitivity

Question 18

Acne

Answer 18

non-inflammatory comedones (pimple, whiteheads, blackheads)

Inflammatory- comdones, eeythematous pustules, cysts- inflammation is due to to propionibacterium acne’s bacteria

Acne vulgaris- adolescent
Acne rosacea- middle to older adults
Acne conglobate-middle adulthood- severe comedones, applies, cysts, nodule, scars

Question 19

Non-melanoma skin cancer

Answer 19

Risk factors- UV exposure, fair skin, family hx, radiation treatment, exposure to chemicals- coal/tar, arsenic compounds

Basal cell carcinoma - epithelial tumour from basal layer of epidermis- impaired ability of Keratinocytes to mature-results in bulk neoplasm that grows and destroys healthy surrounding tissues. Tend to reoccur but less likely to metastasise
- classifies into modular (face/head/neck), superficial (trunk/extremities), pigmented (head/neck- border well defined), morpheaform (rarest-head/neck-looks like flat ivory fleshy coloured scar), keratonic (Peru and post auricular groove- resembles nodular)

Squamous cell carcinoma- tumour of squamous epithelium of skin or mucous membranes. Starts as small firm red nodule with crusted keratin products, extends and becomes nodule and area around nodule hardens, odd shapes

Treatment- surgical excision, mohs surgery (this layers of tumour horizontally shaved off then frozen section stained to determine margins), curettage (scraped tissue), electrodessication (low voltage electrode abrades tumour vase), radiation

Question 20

Melanoma skin cancer

Answer 20

Arise from melanocytes, can form wherever there is pigment. Usually asymmetrical, >6mm. If they penetrate dermis can mix with blood and lymph and metastasis

Risk factors- moles, fair skin, family hx, men, immune suppressive medications, UV, precious melanoma

Prognosis depends on age, metastasis, site, gender, tumour thickness, ulceration

Precursor lesion- congenital naevi, dysplastic naevi (normal mole that becomes irregular), lentigo maligna (Hutchinson freckle-tan/black spot that looks like a freckle)

Classified into
1- superficial spreading melanoma- usually flat and scaly, 2cm, usually from pre-existing mole, radial phase 1-5yrs then vertical phase changes colour from tan/brown/black to red/white/blue with irregular margin and raised nodules
2- lentigo malignant melanoma- radial growth 10-25yrs, size up to 10cm, turn malignant as soon as reach dermal layer
3- nodular melanoma- raised some shape, blue-black or red nodules, look like blood blister. Lesion arises from unaffected skin not pre-existing lesion, has no radial phase, difficult to diagnose before it metastasis
4- acral lentiginous melanoma- more common in dark skin, progresses from tan black flat lesion to elevated nodules 3cm. Radial phase 2-5yrs

Identification- ABCD- asymmetry, border irregularity, colour variation, diameter greater than 6mm

Diagnose- biopsy, CT, chest X-ray, MRI (metastasis)
Micro staging- Clark’s system- stage 1- epidermis, 2-3-papillary dermis, 4- reticular dermis, 5- subcutaneous tissue

Treatment- surgery and excision of local lymph nodes, immunotherapy, radiation therapy, gene therapy, melanoma DNA, immune therapy/vaccine)

Question 21

Pressure ulcers

Answer 21

Occlusion of blood leads to release of waste products and resulting oedema and reduced perfusion to skin, platelets aggregate in endothelial cells surrounding vessels and create micro thrombi which impedes blood flow further=hypoxia and Ischaemia

Risk factors- intrinsic- age (very young/very old), immobility, inactivity, malnutrition, dehydration, poor skin condition, impaired sensory perception, diabetes, malignancy, renal respiratory, vascular, lymphatic and hepatic disorders,
Extrinsic- pressure, shear, friction moisture, contact with surface that increases skin temp

Stages-
1- intact non blanching
2- partial thickness loss of dermis
3- full thickeness subcutaneous fat may be visible and some slough
4- full thickness with exposed bone, tendon, or muscle. Slough or eschar May be present

Management- TIME
T-tissue viability-debridement of dead tissue by surgical sharp, conservative sharp, autolytic, mechanical, chemical, enzymatic, parasitic, eschar=scab (non viable)
I- infection/inflammation- static healing, increased exudate, hypergranulated, bright red, friable, tissue bridging
M-moisture imbalance- excess moisture