Suture Materials Flashcards
Define tensile strength
• Tensile strength: ‘breaking strength per unit area’ (catgut has poor tensile strength however is commonly used)
Define Memory
• Memory: ‘tendency to retain original configuration’ (property that makes it difficult to use – if high memory knots come undone more easily)
Define Chatter /Tissue drag
‘lack of smoothness or friction whilst passing through tissue’ (Lower in monofilament, high in multifilament)
Define Tissue reaction
Tissues respond to the implantation of sutures as they do to other foreign material and can provoke an inflammatory response (more inert materials = less reaction catgut and silk have greater foreign body reaction, synthetic will have lower reaction)
Define knot security
Relates to the surface frictional characteristics of the material
What factor about a wound informs the needle choice?
• The deeper the wound, the more curved the needle
What is the function of the ductility of a needle
Warns the surgeon that the force being placed on the needle is too great (will bend before breaking)
Define Elasticity
• Elasticity – the level that the material can stretch without being deformed
Define Plasticity
• Plasticity – How easily you can change the shape of the material (good for knots etc)
Compare mono and multi filamentous suture material
Monofilament
• Has smooth surface that allows for easy passage through tissues
• Does not support bacterial growth
• Has no capillary action
• High memory (?)
• Stiff ends can cause irritation if the knot is not buried
Multifilament
• Has a rough surface that causes tissue drag
• Potential spaces between the filaments can act as a nidus for infection
• Capillary action/wicking
• Easy to handle
• Soft and pliable, well tolerated by patients
Describe USP
Grading for suture material
• United States Pharmacopia
• Based on tensile strength rather than diameter
• 11-0 to 7
• Increasing size/strength (11-0, 10-0, 9-0 … 0 … 1, 2, 3, etc)
Describe metric system
Metric
• 1/10mm of diameter of suture (‘2’ = 0.2 mm)
• 0.1-10
Describe Suture Dehisence
• Knot slippage • Knot breakage • Tissue laceration • Weakening of the suture during its handling; crushing, shearing, etc.
Give two advantages and two disadvantages of simple interrupted sutures
ADVANTAGES Secure – if one knot fails then the wound is still secure Can adjust tension – you can replace individual sutures if tension is not correct DISADVANTAGES Slower – longer surgical time More suture material – Cost More foreign material
What are cruciate matress sutures good for?
GOOD FOR
Skin Closure
Wounds under tension
