Fundamentals of Plastic Surgery Flashcards
What are the two main layers of skin?
Epidermis
Dermis
What kind of tissue is the dermis?
Connective tissue
Also contains rich dermal vascular plexus
What kind of cells are in the epidermis?
Stratified squamous epithelium
What are the functions of skin?
Protection/involved in immunological response to damage by: direct trauma, chemicals, biological agents (e.g. fungi/bacteria), radiation, e.g. sunlight Synthesis of vit D Regulation of body temperature Fluid balance Sensation Social/aesthetic
Define wound
End result of damage to the skin/other structures secondary to trauma
Define bruise
Area of injury associated with escape of blood from rupture vessels underneath due to trauma
How do the colours of bruises change over time?
Initially black/red –> yellow
Why do bruises change in colour over time?
Due to Hb breakdown
What is the medical word for a bruise?
Contusion
What is an abrasion?
Graze/minor wound caused by rubbing/scraping of skin
What will increase the change of an abrasion leaving a nasty scar?
If it is contaminated
What is a laceration?
Tear of tissue/organ secondary to being stretched
What are the edges of a laceration like?
Irregular with compromised blood supply
What causes an incision?
Sharp object, e.g. knife/scalpel
What does the edge of a incision look like?
Clean, well defined with viable vascularity to the wound edges
What is a degloving injury?
Laceration in which skin is sheared from the underlying fascia by rotational/crushing forces
May lead to tissue ischaemia as blood vessels are torn
What is an avulsion injury?
Tearing/forcible separation of a structure from its origin, e.g. a finger being pulled off
How should any wound be initially managed?
- Wound inspection +/- exploration
- Wound lavage - wash out with 0.9% saline
- Wound excision - excise unhealthy/devitalised tissue
- Wound closure
If a wound is really contaminated when should it be closed?
NOT after first wound management procedure
Usual for patients to return to theatre after 48h for a second look where steps 1-3 are repeated and then wound may be closed
NEVER close a dirty wound!
What is the reconstructive ladder?
A ladder of ways to close wounds, from the best way to the least desirable
What are the rungs of the reconstructive ladder (from the bottom (i.e. best) to the top (i.e. worst))?
Primary suture/delayed primary suture Split thickness skin grafts Full thickness skin grafts Local flaps Distant/free flaps
What is primary suture?
Bringing edges of skin together with sutures at time of initial wound assessment
What is delayed primary suture?
Suturing of wound at a later date, following steps 1-3 of wound management
Where might primary suturing not be used?
If wound is grossly contaminated and wound closure would –> infection
Wound breakdown/extensive abrasions where no definite edges to close
What is healing by secondary intention?
Not bringing the edges together by suturing
What are the disadvantages of healing by secondary intention?
Unsightly wound
Prolonged healing
What is a skin graft?
Piece of skin (part/full thickness) that is completely detached from its donor site and moved at a recipient site
How does the donor site of a split thickness skin graft heal?
By granulation
What do split thickness skin grafts consist of?
Epidermis and variable amounts of dermis
What do full thickness skin grafts consist of?
Entire dermis and epidermis
How does the donor site of a full thickness skin graft heal?
Requires closure
To survive a skin graft must do what two things?
Gain attachment to the recipient site and gain a blood supply - known as ‘taking’
How does the graft adhere?
Fibrin deposition which is gradually replaced by collagen
How do grafts receive a blood supply?
Vessel ingrowth from graft recipient site
Where can skin grafts not be used?
Bone stripped of periosteum Tendon stripped of paratenon Cartilage stripped of perichondrium Exposed metalwork Open joints
What makes a suitable and what makes an unsuitable bed for grafts?
Muscle/fascia - suitable
Fat - unsuitable
What may cause graft failure?
Excessive mobility –> shearing between graft and recipient
Haematoma
Cross contamination of recipient site
How can excessive mobility of a graft be prevented?
Plaster splint
Why do haematomas cause graft failure?
Lift graft off its bed
Locus for infection
What is a flap?
Transferable block of tissue that may/may not include skin and which has its own blood supply
When are flaps used?
To reconstruct defects when either the recipient area has an insufficient blood supply of its own to allow healing by a technique like grafting or when some characteristic of tissue transferred is desirable, e.g. skin colour match
How does the skin receive its blood supply?
Via the dermal plexus lying in the underlying fascia
What causes a crush injury?
Compressive forces
What are puncture wounds?
Penetrating injuries caused by sharp objects
These have a potential to damage deep structures and allow infection/FBs to be carried deep into the wound
What is a haematoma?
Accumulation of blood within a tissue, organ or space which clots and forms a solid swelling
What is the natural cycle of a haematoma?
Clotting and liquefaction –> gradual resorption
What symptoms/complications can haematomas cause?
Discomfort
Compression of nearby structures
Increased risk of infection (haematomas provide ideal culture for various organisms)
What is an ulcer?
Discontinuity of an epithelial surface which fails to heal spontaneously
What are ulcers usually associated with?
Infection or inflammation
What is a sinus?
A blind track, lined by granulation tissue leading from an epithelial surface into the surrounding structures
What is a fistula?
Abnormal connection between two epithelially lined surfaces, e.g. gut and skin
How are traumatic wounds generally categorised?
Clean - usually surgical/incised with no devitalised tissue
Contaminated - contains foreign material/devitalised tissue
How can clean wounds generally be managed?
Primary closure
How are contaminated wounds generally managed?
Must be converted to a clean wound first