Suturing in depth Flashcards
Purpose of suturing (3)
a) approximate tissue until healing takes place
b) ligate vessels
c) tag fragile or important structures
Suture material selections are based on (3)
a) biologic and mechanical performance
b) structure to be sutured (tendon, fascia, skin, vessels, bone)
c) bacterial presence
—contaminated(monofilament)
—clean
Suture characteristics (7)
1) strength and tread dimension
2) suture volume
3) elongation
4) flexibility
5) monofilament vs. braided
6) capillarity
7) coating
strength and tread dimension
varies with basic material composition and dimensions
suture volume
use of smaller sutures decreases foreign body volume but sacrificies knot pull strength
elongation (3 properties)
1) elasticity allows a return to original length with cessation of strain. (good ones are stainless steel, braided polyester, catgut, and silk)
2) plasticity allows elongation to persist with cessation of strain (polypropylene)
3) intermediate types posses both elastic and plastic properties
flexibility
based on material and diameter of suture.
-small diameter is more flexible
-silk, dexon is flexible
-nylon, catgut is stiff
monofilament vs. braided
monofilament has a low coefficient of friction and is better suited for contaminated wounds
braided has a high coefficient of friction, greater strength, and capillarity
capillarity (2)
1) fluid and bacteria may penetrate into interstices of braided sutures
2) PMN’s and macrophages too large to reach interstices
coating (3)
1) help decrease capillarity
2) improves handling
3) reduces tissue drag
Suture needles desirable characteristics (4)
1) Made of high quality stainless steel
2) slim as possible without compromising strength
3) sharp enough to penetrate tissue with minimum resistance
4) rigid enough to not bend but ductile enough to not break
suture needle anatomy (3)
1) suture attachment
2)body
3)point
suture important measurements (4)
1) chord length
2) needle radius
3) needle diameter
4) needle length
suture attachment type (3)
closed
french
swaged
-most common suture attachment
-decreases tissue damage
different types of needle bodies (6)
1) straight
2) 1/2 curved
3) 1/2 circle (most common)
4) 1/4 circle
5) 3/8 circle
6) 5/8 circle
different geometric shapes of needle body (4)
1) round
2) flat
3) oval
4) triangular
Different types of needle points
1)blunt
2)tapered
3)cutting
blunt needle point
used for friable tissue
tapered needle point (2 points)
-useful for tissue offering little resistance
- used on paratenon, tendon sheath, and subcutaneous tissue
types of cutting needle points (2)
conventional and reverse
conventional cutting needle point (3)
-cutting edge is located on the concave side
-cuts through dense, difficult to penetrate areas
- care must be taken not to rip through tissue
Reverse cutting needle point (3)
- cutting edge located on the convex curvature
-prevents needle from ripping through tissue
-greater strength given
suture types (2)
absorbable and nonabsorbable
In what amount of time will absorbable sutures lose their tensile strength
approximately within 60 days
types of absorbable sutures ( 2)
natural and synthetic
How are natural sutures degraded
by lysosomal enzymes
types of natural sutures (2)
catgut and collagen
characteristics of catgut:
- what is it made out of
-how to achieve greater strength
-how is it stored
-tissue reactivity
-made from submucosa of sheep intestine or serosa of bovine intestine
-greater strength achieved by treatment with chromic salts and formaldehyde
-stored in alcohol for preservation
-highest tissue reactivity of all sutures
characteristics of collagen:
-what is it made out of
-what is its main use
-tissue reactivity compared to catgut
-made from long flexor tendon of steer
-primarily used in ophthalmic surgery
-less tissue reactivity than catgut
how are synthetic sutures degraded
through hydrolysis
types of synthetic sutures (5)
-polyglycolic acid (dexon)
-polyglactin (vicryl)
-polydiaxonone (PDS)
-polyglyconate (maxon)
-poliglecaprone (monocryl)
Characteristics of polyglycolic acid (dexon):
-braided or monofilament
-knot pull and tensile strength?
-reactivity
-time for complete absorption
-use
-braided
-good knot pull and tensile strength
-very inert
-completely hydrolyzed in 100-200 days
-used in skin and subcutaneous tissue
Characteristics of polyglactin (vicryl):
-braided or monofilament
- important time marker of tensile strength
-reactivity
-time for complete absorption
-braided
-65% tensile strength will remain at 14 days
-very inert
-completely hydrolyzed at 80 days
characteristics of polydiaxonone (PDS):
-braided or monofilament
-flexibility and tensile strength
-reactivity
-time to absorption
-important time marker for tensile strength
-monofilament
-high flexibility and tensile strength
-completely hydrolyzed in 90 days
- very inert
-70% tensile strength at day 14
characteristics of polyglyconate (maxon):
-braided or monofilament
-special characteristics in regards to kinking and curling
-what happens when exposed to tissue fluid
-time to complete absorption
-monofilament
-resists kinking and curling
-becomes softer as it is exposed to tissue fluid
-completely hydrolyzed at 180 days (longest of any absorbable suture)
characteristics of Poliglecaprone (monocryl):
-braided or monofilament
-pliablity and reactivity
-time til complete absorption
-important time marker for tensile strength
-monofilament
-very pliable and inert
-completely hydrolyzed in 90-120 days
- 20-30% tensile strength remains at 14 days
how long do nonabsorbable sutures maintain their tensile strength
generally for longer than 60 days
types of nonabsorbable sutures (2)
natural and synthetic
types of natural nonabsorbables (2)
silk and cotton/linen
Characteristics of silk:
-What is it made from
-handling properties
-impregnated and coated with?
-tissue reactivity
-tensile strength
-made from silk of the silk worm
-known for superior handling properties
-impregnated with mixture of waxes and silicone
-low tensile strength which is completely lost at 360 days
-highly tissue reactive
Characteristics of cotton/linen:
-reactivity
-tensile strength
Similar characteristics to that of silk
-increased tissue reaction
-very low tensile strength
-weakest of all sutures
types of synthetic nonabsorbable sutures (4)
-nylon
-polyester
-polypropylene
-stainless steel
Characteristics of nylon (ethilon,surgilon):
-in terms of memory
-elasticity
-tensile strength
-reactivity
-monofilament or braided
-use in contaminated wounds
-possesses memory
-elastic in nature therefore well suited for retention and wound closure
-high tensile strength
-low tissue reactivity
-can be found as a monofilament and braided
-may be used in contaminated wounds
Characteristics of polyester (ethibond, dacron):
-braided or monofilament
-strength
-reactivity
-coated with
-special use
-braided
-has high tissue strength
-low tissue reactivity
-may be coated with silicone for smoothness, reduces tissue trauma
-used when strong apposition of tissues is needed indefinitely
Characteristics of polypropylene (prolene, surgilene):
-reactivity
-braided/monofilament
-pliability and handling
-tensile strength
-drag
-use in contaminated wounds
-very inert
-monofilament
-better pliability and handling than nylon therefore holds knots better
-excellent tensile strength
-passes through tissue with minimal drag
-often used in contaminated wounds and plastic surgery
Characteristics of stainless steel (flexon)
-braided/monofilament
-corrosion
-reactivity
-what negatives can occur
-uses (3)
-can be found in monofilament or braided forms
-may corrode especially at stress points
-cause mild to moderate tissue reactivity
-may fracture, fatigue or kink
-used for bone fixation, tendon repair, and retention sutures
