Flashcards in Suturing Deck (39)
Describe a swaged needle
Passes through tissue with less drag than eyed needle
As a new needle is used each time, it is sharp
Suture is secured to the needle
Useful for delicate tissue as less traumatic
Describe an eyed needle
Greater bulk at eye increases drag (needle should not be double threaded)
Needles are commonly re-used and therefore cheaper
Care must be taken to keep needle joined to the suture
The choice of needle shape is often governed by...
the accessibility of the tissue to be sutured. The more confined the operative site, the greater the curvature needed
What are the most commonly used needles in practice?
Round bodied needles are designed to...
separate tissue fibres rather than cut them. Leak proof suture line.
Describe a taper point needle
Needle body is rounded and tapers to a point
Combines initial penetration of a cutting needle with the minimised trauma of a round bodied needle.
Describe a blunt point needle
Designed for suturing extremely friable tissue such as the liver
What are cutting needles used for?
Required for suturing fibrous or dense tissues
Describe a reverse cutting needle
Body of needle is triangular with apex on outside of needle curvature
Describe a regular cutting needle
Body of needle is triangular with apex on inside of the needle curvature
Describe absorbable suture material
Undergo degradation and loss of strength after 60 days
Used internally where long term support is not required
Describe non-absorbable suture material
Maintain their tensile strength for longer than 60 days
Neither phagoctosed or hydrolysed, encapsulated within fibrous tissue
Describe natural suture materials
Come from naturally occurring organic fibres
Describe synthetic suture materials
Made from 'man made' fibres
Synthetic materials are hydrolysed and tend to produce minimal tissue reaction
What are suture materials described as monofilament or multi-filament?
Depends if they are made from multiple strands or single strand
Extent to which tissue fluids are attracted along a length of suture material
The lack of smoothness as a throw of knot is tightened down
smoothness = no chatter
Secondary coating over primary material to modify
Describe knot security
Relates to the surface frictional characteristics of the material
The tendency of the material to return to its original shape
Often mono-filaments that have good memory
Describe tensile strength
Breaking strength per unit area of tissue
Describe tissue drag
The degree of frictional force as the material is pulled through the tissue
Describe tissue reaction
The response of the tissue to the suture material involved
Synthetic suture materials cause...
less tissue reaction
Mono-filament materials are...
less reactive and much less likely to harbour bacteria
have more tissue drag and cause more tissue tension
Bacteria harbour in between...
the fibres of braided materials
Most braided materials are now...
coated to reduce tissue drag, but this reduces knot security