Skin Surgery Flashcards
How will a skin biopsy be useful in a patient presenting with a rash?
Aids diagnosis
Why is a skin biopsy useful in a patient with a tumour?
assist in diagnosis
remove malignancy
remove unwanted skin growth
Would you excise a Basal cell carcinoma or a Dermatofibroma?
Basal Cell carcinoma
Do you normally excise basal cell papillomas or common melanocytic naevi?
No
Why may the biopsy of a rash not provide a diagnosis?
different skin conditions may have same histology
eg. different types of eczema look similar on histology
one cause of a skin condition can have several histology patterns
eg. drug eruption
Give examples of the various reactions which can occur as a drug reaction to amoxicillin
morbilliform (measles like) eruption urticaria angiodema fixed drug eruption generalised pustulosis
What treatments other than surgery can be used for skin cancers?
Photodynamic therapy cryotherapy Chemo/Radiotherapy 5-fluorouracil solaraze Imiquimod
What factors must be considered before carrying out skin surgery?
nature of procedure medical Hx drug Hx bleeding disorder allergies other- pacemaker, valve defect, epilepsy, diabetes
Give examples of what parts of a patients drug history would alert you before starting a surgical procedure
STEROIDS - increased rate of infection post-op
- poor wound healing
ASPIRIN - increased bleeding rate from wound
What parts of the underlying anatomy should you be aware of when making a surgical excision on the face
tiger country eyelids hairline vermillion scalp skin tension lines
What parts of the face are considered to be “tiger country?”
Temple - due to superficial temple artery
Front of ear - facial nerve through parotid gland
Side of neck - “Erb’s” point - nerves to ear and joining spinal accessory nerve to shoulder
What are the 5 layers of the scalp?
S - skin C - connective tissue A - aponeurosis L - Loose connective tissue P - parietal bone
A patient presents with a 2 day history of pain over right side of forehead and nose followed by development of crusty vesicles in the same area. What is the suspected diagnosis?
Shingles in the ophthalmic division of the trigeminal nerve
CN V1
What cranial nerve is damaged if the patient complains of numbness over the middle of their cheek?
CN V2 (maxillary division)
What nerve is thought to be damaged if a patient presents having been previously well with no history of injury but then experiences sudden loss of movement on right side of his face?
Facial Nerve
What trauma of the jaw could interrupt the sensory nerve supply to the chin, and what nerve would be damaged?
Fracturing the mandible may interrupt the CN V3 nerve(mandibular division)
How could you clinically test the motor function of the facial nerve? (CN VII)
ask the patient to:
frown
close eyes tightly
What methods of local anaesthesia are available?
topical
local infiltration
nerve block
field block
Give an example of a common drug used for local anaesthesia
lignocaine (lidocaine)
In what situations would excretion of lignocaine (lidocaine) be reduced?
excretion reduced in liver, renal, cardiac failure, young and elderly
What is the maximum safe dose of lignocaine (lidocaine)?
max safe dose: 50 ml 1% lignocaine with adrenaline
Why is adrenaline added to local anaesthesia?
prolongs anaesthesia
reduces bleeding
When should the use of adrenaline in local anaesthesia be avoided?
avoid in fingers and toes
avoid in patients with cardiac disease, and those on psychotropic drugs
How do you make local anaesthetic injections less painful?
relax patient fine needle omit adrenaline neutralise acidity massage skin slow injection subcutaneous injection follicle opening nerve blocks
Why is it important for local anaesthetic to be a subcutaneous injection rather than into the dermis of the skin?
Dermis contains nerve endings
=> would be more painful
What are the common complications of taking a skin biopsy?
bleeding wound dehiscence infection scarring motor or sensory nerve damage loss of function
What alternative types of surgery are available
laser photodynamic therapy dermabrasion plastic surgery Mohs micrographic surgery
What is electro-surgery commonly used for?
haemostasis - stops bleeding
Tx of minor skin lesions eg. skin tags
Describe the process of curettage and cautery
Local anaesthesia
curette to scrape off lesion
wound cauterised to stop bleeding
wound left to granulate and heal
What are the advantages and disadvantages of curettage and cautery?
ADV:minimally invasive procedure
DISADV: pathology specimen does not accurately record the margins of the tumour
What other locally invasive procedures are often used for skin lesions?
Shave excision
punch biopsy
What are the advantages and disadvantages of a punch biopsy?
ADV:
quick
produces good wound edges
Only one suture required
DISADV:
difficult to judge depth
round holes do not always heal well
pathology sample may be too small
Skin grafts are more cosmetically appealing than skin flaps TRUE/FALSE?
FALSE
skin grafts often display different tone and texture therefore don’t match
Where do malignant melanomas commonly metastasise to?
Lung
Liver
Brain
Why is it important to consider the anatomy of the eyelids when carrying out a surgical excision?
If the eyelids become damaged, eye can become damaged quickly by patient
Why is the hairline an important anatomical part to consider when carrying out a biopsy?
important for cosmetic appearance
Why is the scalp an important anatomical region to consider when taking a skin biopsy?
Extremely vascular therefore bleeds very easily
Why is an excision performed in an elliptical shape and not a circle?
Round wound would pucker up
elliptical excision heals in a cosmetically acceptable fashion
ellipsis scars can be hidden in folds of skin much more easily
