L5 Wound Healing and Management

Question 1

define an abrasion, how are they caused?

Answer 1

partial thickness, dermis still present, caused by shear force

Question 2

define a puncture, how is it caused?

Answer 2

deep tissue injury and intro of contamination caused by sharp penetrating trauma

Question 3

describe a laceration

Answer 3

sharp linear incision involving epidermis and dermis

Question 4

describe de-gloving (incl. physiological)

Answer 4

wounds that involve elevation of sections of skin caused by tearing due to sheer forces
physiological: skin is lost due to interuption of vascular supply, ichaemia and necrosis 5-7 d following injury.

Question 5

list the 4 wound configurations incl brief description

Answer 5

clean - created surgically
clean contaminated - created acutely, has bacteria
contaminated - wound w/ foreign material present
infected - wound contaminated >10^5 bacteria burden

Question 6

list the 4 stages of wound healing

Answer 6

stage 0 - immediate response
stage 1 - inflam and debridement
stage 2 - proliferation and repair
stage 3 - remodelling/maturation

Question 7

describe the processes that occur in stage 0

Answer 7

• formation of blood clot

- -> washes wound, releases vasoactive compounds

Question 8

describe the processes that occur in stage 1, incl. timeline, cells involved, gross appearance.

Answer 8

• inflammation and debridement
  timeline: 0-5 d
  cells involved: neutrophils, macrophages
  gross app: erythema, oedema, heat, pain, exudate, necrotic material, contamination
• cytokines from clot regulate cellular activity , neutrophil migration followed by monocyte migration.

Question 9

describe the processes that occur in stage 2: incl timeline, main cell involved, gross app
what are the 3 sub stages that occur during stage 2?

Answer 9

timeline: 4-12 days
imp cells: fibroblasts, endothelial cells, myofibroblast
app: gran tissue, wound closure ,
stage will not progress is foreign body still there.
a) creation gran tissue (collagen synth, vascularisation)
b) contraction
c) re-epithelisation

Question 10

describe the processes that occur in stage 3: incl timeline, main cell involved, gross app

Answer 10

timeframe: 7-14 d
imp cell: fibroblast
gross app: scar tissue, hair growth
- type III collagen replaced w/ type I, type I fibres cross linked along lines of tension

Question 11

what are some local and systemic factors that effect wound healing

Answer 11

local 
- infection 
- tension 
- necrotic/foregin material 
- moisture level 
- poor vasculature 
- fluid accum: O2 can't diffuse
systemic
- poor perfusion 
- hyperadrenocorticism 
- diabetes mellitus
- immunocompromised
- obesity

Question 12

which wound configurations can be closed primarily?

Answer 12

clean wound

clean contaminated wound (need antibiotic tho)

Question 13

what does primary closure of a wound require?

Answer 13

• suture wound edges directly
• healthy tissue
• eliminate dead space
• minimise dead space

Question 14

what are some primary closure tension relieving techniques?

Answer 14

• pre suture
• undermining
• subcutaneous suture
• mattress suture
• releasing incisions
• reconstruction

Question 15

when would you use delayed primary closure of a wound? if doing a delayed primary closure when should you close the wound? does this occur before or after gran tissue formed?

Answer 15

if the wound can’t be immediately closed ie/ wound contaminated or if awaiting lab results eg/ neoplasia
close within 2-5 day of wound, BEFORE gran tissue formed

Question 16

does secondary closure of a wound occur before or after granulation tissue formation?

Answer 16

AFTER

Question 17

what are the methods of surgical debridement

Answer 17

layered debridement - taking layers
enbloc resection - remove whole wound
lavage - application of fluid to remove contaminant , effectively diluting wound

Question 18

what is the aim of secondary intention healing

Answer 18

aim: bandaging to provide suitable wound microenvironment to favour rapid healing
allow wound to heal fully via contraction and epithelisation before closure.

Question 19

what are some examples of bandages

Answer 19

robert jones
modified robert jones
tie over bandage
abdominal/thoracic bandage

Question 20

what are the three layers of a bandage what are their roles?

Answer 20

1. contact layer- set microenvironment
2. intermediate layer - padding and distribute forces evenly across bandage
3. outer layer - coaptation, immobilisation

Question 21

what are two examples of the contact layer

Answer 21

film

foam

Question 22

list some absorbent dressings

Answer 22

hyper osmotic agents - honey, sugar, hypertonic saline

Question 23

why is honey a good absorbent dressing?

Answer 23

also has antimicrobial, dehydrates bacteria and kills potentially w/ hydrogen peroxide.

Question 24

describe negative pressure wound therapy:

Answer 24

open cell foam (400-600micron pores) adhered to wound w/ airtight plastic. tube placed attached to pump, applies negative pressure -125mmhg. sub atmospheric pressure promotes granulations, increases blood flow, re-epithelisation.