Suture Materials Flashcards
Sutures hold a wound in apposition until…
the natural healing process is established enough to make support from the suture material unnecessary.
What is the adequate duration on average for sutures being left in the body?
14-21 days on avg, except tendon
In the early stages of wound healing, wound strength is due to…
- fibrin from inflammatory reaction
- vascular endothelial ingrowth
- epithelial migration into wound
What factors are likely to influence wound healing?
infection
tension
severe protein depletion
poor vascularisation
What biological properties of suture material have to be considered?
- the likelihood of the material to potentiate infection
- calculogenic?
suture strength should match…
tissue strength
The rate of loss of suture strength must be compatible w/ the…
the rate of gain of wound strength
Define: ‘Straight pull’ tensile strength
Represents the maximum longitudinal force a strand can bear before breaking
Define: ‘Knot-pull’ tensile strength
The force which a suture strand can resist before it breaks when a knot exists
Define: ‘Out of packet’ tensile strength
This is the ‘straight pull’ tensile strength
AKA the original tensile strength
Define: Tensile strength
Time suture will mechanically support the wound, usually measured in days
Define: Mass absorption
Time in days for suture to be totally absorbed by the body
What is the Critical wound healing period (CWHP)?
The time in days a wound requires mechanical support
What is the metric number used in the metric system of suture size?
Metric number = the thread in diameter in tenths of a mm
Explain the USP system of suture size.
System has a standard range in diameter for each size or grade
Denoted in zeros with the finest is (14-0) and a max diameter is at 7.
What are the ideal properties of suture material?
- low cost
- easily sterilised
- pliable
- high tensile strength
- non-capillary
- secure knots
- no tissue rxn
- absorbed/encapsulated
What are the 3 classifications of suture?
- Absorbable or non-absorbable
- Multifilament or monofilament
- Natural or synthetic
What are the different types of absorbable suture that are commonly found?
Catgut, Chromic catgut, Polyglycolic acid (Dexon), Polyglactin 910 (Vicryl/Vicryl RAPIDE), Polydioxanone (PDS), Polyglyconate (Maxon), Poliglecaprone 25 (Monocryl), Glycomer 631 (Biosyn), Polyglytone 6211 (Caprosyn)
Catgut is …
natural, absorbable, monofilament
Catgut is made from the submucosa of…
sheep/cattle
Plain gut (catgut) evokes…
severe sterile pyogenic reaction
Catgut loses tensile strength…
rapidly
How long does it take the body to absorb catgut?
about 7 days
What is important to remember about plain gut (catgut)?
Plain gut should not be used in Surgery
Chromic catgut is…
natural, absorbable, monofilament suture
What differs chromic catgut from plain gut?
Chromic catgut has a chromic oxide treatment to reduce inflammatory reactions in the body. It has a higher tensile strength for longer and a more even absorption pattern
What are some advantages of chromic catgut?
- relatively cheap if purchased in cassettes
- easy to handle
What are some disadvantages of chromic catgut?
- severe inflammatory rxn
- poor knot security
- questionable sterility in cassettes
- variability in strength & loss of strength
- swells & weakens when wet
- weakens when knotted
- capillary action
Polyglycolic acid (aka Dexon)
Synthetic, multifilament, absorbable
How is Polyglycolic acid broken down? What does this do to the body?
It is broken down by hydrolysis thus making it less reactive to the body than catgut.
Polyglycolic acid has better… than catgut.
knot security
The strength of polyglycolic acid is … by knotting than catgut
less affected
polyglycolic acid has some …. due to the ….
tissue drag
multifilament synthetic braided suture
What suture is the main competitor to polyglycolic acid?
Polyglactin 910
Polyglactin 910 (Vicryl) is a
synthetic, multifilament, absorbable suture
Why is polyglactin 910 a competitor for Polyglycolic acid?
it is marginally stronger than the polyglycolic acid
When is it ideal to use Vicryl rapide?
Superficial soft tissue (skin & mucosa) where only short-term wound support is required.
How long does vicryl rapide last?
about 7-10 days
Vicryl rapide should not be used for…
ligation, cardiovascular, GIT, etc
Polydioxanone is also known as
PDS
polydioxanone is a
synthetic, absorbable, monofilament