Wound Assessment Flashcards
What is wound healing by primary intention?
Primary intention is the healing of a clean wound without tissue loss e.g. surgical incision
What is wound healing by secondary intention?
Secondary intention is the healing of a wound with considerable tissue loss and in which the edges cannot be brought together
What are the phases of wound healing?
How long does the substrate (inflammatory) phase of wound healing last for?
Up to 5-7 days
Explain the inflammatory phase of wound healing
Inflammatory cells migrate into the wound (chemotaxis) and promote the inflammatory phase, which is characterised by the sequential infiltration of neutrophils, macrophages, and lymphocytes.
Explain the proliferative phase of wound healing
Once the wound is cleared of devitalised tissue, the arrival of fibroblasts produce collagen (type I and III) within the wound bed which cross-links and imparts strength to the scar. Wound revascularisation also occurs at this time.
What characterises the maturation or remodelling phase of wound healing?
A gradual gain in tensile strength due to continued collagen deposition and collagen remodelling (type III collagen is replaced with type I)
How does RhA lead to anaemia?
During conditions in which hepcidin level is abnormally high, such as inflammation (e.g. RhA), serum iron falls and this typically leads to anaemia due to an inadequate amount of serum iron being available for developing RBCs
How does anaemia (secondary to RhA, SLE, etc.) or hypoxia (secondary to PVD) affect wound healing?
An anemic state decreases the amount of oxygen available to the tissues, which increases the opportunity for bacterial colonisation. In addition to hypoxia, PVD also results in a reduction of nutrients to the tissues and cells necessary to fight bacteria
How does smoking affect wound healing?
The nicotine and other chemicals present in tobacco have vasoconstrictive properties, thus inducing hypoxia to the tissues and impeding wound healing
How does infection affect wound healing?
Bacteria compete with the newly forming tissue for nutrients and oxygen and leads to eventual tissue starvation (anoxia). Tissue anoxia produced by bacteria results in further tissue breakdown; aerobic bacteria complicate this environment further due to their high oxygen consumption.
Why are WBCs recruited during the inflammatory phase?
Neutrophils and monocytes are recruited to debride the wound by phagocytosis
How do glucocorticoids impair wound healing?
- Recruitment of WBCs in the inflammatory phase is suppressed
- Inhibit fibroblastic proliferation
- Reduce collagen production
What’s the difference between a hypertrophic and a keloid scar?
Hypertrophic scar is a result of unchecked (excessive) proliferation of fibrous tissue but remains confined to the skin injury, whereas a keloid scar invades the surrounding normal skin i.e. beyond the incision scar
What’s gold standard to offload diabetic foot/heel ulcer?
Total contact cast (TCC)
Name the stages of bone healing
Describe the inflammation stage of bone healing
- There’s haemorrhage between bone ends
- Inflammatory cells accumulate (cellular proliferation) at # line and macrophages phagocytose tissue debris
- Bone necrosis occurs as a result of tearing of blood vessels