Biomedical Cell Biology: Hypertrophic Scars and Keloids

pressure ulcers: predominantly the elderly/ paralysed/ critical care

skin ischaemia from sustained pressure (head sacrum)

defined as: a localized area of tissue necrosis taht developes when soft tissue is compressed between a bony prominence and an external surface for an extended period of time

STAGES

red/blue discolouration, impeaded capillary flow STAGE 1

rapid tissue necrosis leads to partial thickness skin loss, epidermis STAGE 2

full thuckness loss destruction of subcutraneous tissue STAGE 3

eventually damage to muscle bone and supporting structures STAGE 4

incidence 2.7% in acute care hospitals. 23-37% mortality rate

prevention: identify at risk pateints, frequent position changes, pressure relieiving aids (air filled matress, water bed, pillows and lifting devices.

releive pressure points, debriment (removal of necrotic tissue) specialised dressings

diabtetic

peripheral neuropathy: increase risk, diabetic sore. 5.5% of leg ulcerations UK

constant pressure or mechanical trauma (toe joints, ankle/ knee)

loss of feeling due to microangiopathy (micovascular injury involving small blood vessels that supply peripheral nerves, nerves begin to die)

treatment: same as before. amputation if necessary.

patients: avoid by inspecting feet regularly, proper fitting shoes

type 1: treated with insulin

type 2: treated with hypoglycaemic agents

vasuclar dysfunction in diabetes

Advanced gylcation end products (AGEs) formed through glucouse reaction with cellular proteins implicate dysfunction of vascular epithelium

Macrovascular (large vessel) disease can lead to atherosclerosis and thrombosis

Microangiopathy (small vessel damage) leads to retinopathy and peripheral nerop

Normal scar production

fibroblasts migrate into the wound from neighbouring undamaged tissue (dermis)

fibroblast deposit a temporary matrix of the fibrous…