Suture Material and Needles Flashcards
What is suture? In what 2 ways does it play an important role in wound repair?
strand of material used to tie off vessels and approximate tissue
- provides hemostasis
- supports wound healing
What are the 9 characteristics of an ideal suture?
- easy to handle (consistent performance)
- minimally reacts in tissue
- inhibits bacterial growth
- secures hold when knotted (high knot security and safety)
- resist shrinking in tissue
- absorbs with minimal reaction (good and predictable)
- no capillarity
- gentle passage through tissue
- maximum tensile strength with high breaking strength
What is tensile strength? How is it related to size?
measure of the ability of the suture material to resist breakage or deformation (time to lose 70-80% of initial strength)
exponentially proportional to size (large size = high strength)
What is pliability/flexibility? What 2 things does it depend on? What is desirable for vessel ligation?
ease when suture material is handled
- material
- size
more flexibility is better for vessel ligation - falls tighter
What is memory? Why type of material tends to have a lot of memory?
tendency of suture material to return to its original shape
monofilament > multifilament
What is surface friction? What type of material tends to have a high surface friction?
the roughness of the outer surface and its tissue drag (ease when the suture is pulled through the tissue)
braided suture has more drag (high surface friction) than monofilament suture
- rough = more damage
What is knot security? How is it related to suture size?
ability of suture material to hold a knot
inversely proportional to suture size (large size = low security)
What is capillarity? What sutures have and do not have capillarity?
process by which fluid and bacteria are carried into the interstices of multifilament fibers, allowing infection to persist in suture
- monofilament = noncapillary
- multifilament/braided = capillary
(DON’T use multifilament fibers in infected/contaminated tissues)
What is tissue reactivity? How does the type of fiber affect the degree of tissue reactivity?
degree to which the body tends to react to the presence of a particular suture material
natural fiber > synthetic suture
multifilament > monofilament
What is important to note with suture selection?
no single suture is ideal for every surgical situation - certain materials are better suited for different wound environments and uses
What are the 5 ways of classifying sutures?
- FIBER ORIGIN: synthetic (manmade, nylon) vs. natural (biological, silk)
- STRUCTURE: monofilament vs. multifilament
- BEHAVIOR: absorbable vs. nonabsorbable
- ANTIMICROBIAL: “plus”
- SIZE
Suture samples:
What is the difference between absorbable and nonabsorbable sutures?
NONABSORBABLE: maintains >50% of tensile strength for greater than 60 days
ABSORBABLE: loses >50% of tensile strength in less than 60 days
How does tensile strength relate to absorption?
loss of tensile strength does not equal rate of absorption
Why is it important to select the suture with the appropriate absorption rate to the healing rate?
accelerated and premature absorption can lead to post-operative complications if the suture is absorbed before the wound is repaired
- ongoing infection and fever, and pH can affect absorption
How are natural fibers and synthetic fibers absorbed? How do they compare?
NATURAL: enzymatic digestion —> rate of absorption increases in the presence of infection and inflammation
SYNTHETIC: hydrolysis —> water molecules penetrate suture material causing the breakdown of suture polymer chain
synthetic hydrolysis leads to less tissue reaction than natural enzymatic digestion
What does suture duration include?
loss of tensile strength (suture strength) and absorption
What should be considered when choosing suture?
- How long will the sutures need to be in?
- How does the suture material affect the tissue and process of healing?
- How great is the risk of infection?
- What strength of suture is required?
- Is the material flexible enough for the given purpose and is it possible to knot in the space provided?
Why are multifilament sutures avoided when dealing with potentially contaminated tissue? What should be used?
it will most likely convert the contaminated wound into an infected one
absorbable monofilament!
What is the origin of surgical gut? What is its structure?
NATURAL - sheep intestine submucosa or bovine serosa (<90% collagen)
- enzymatic digestion/phagocytosis
multifilament (more drag)
Why is surgical gut not commonly used in practice? How does the type of surgical gut affect this?
marked inflammatory response, especially in cats (most reactive suture material)
chromic gut is treated with chromic acid salts and is less reactive
What is surgical gut most commonly used for?
vascular pedicle ligation
What is another name for polyglactin 910? What is its origin and structure? What is its reactivity like?
vicryl
SYNTHETIC; braided, multifilament (more drag)
minimal tissue reactivitty
What is another name for polyglactin 910? What is its origin and structure? What is its reactivity like?
vicryl
SYNTHETIC; braided, multifilament (more drag)
- monofilament is only 9-0 and 10-0
minimal tissue reactivity
How does Vicryl (Polyglactin 910) absorb?
- 25% of strength is lost by day 14
- completely absorbed by 60-70 days
What are 4 common uses of Vicryl (Polyglactin 910)?
- soft tissue approximation
- hollow organs
- ophthalmic procedures
- subcutaneous procedures
How is Polyglactin 910 altered to make Vicryl Rapide? How does absorption compare to Vicryl?
exposed to cobalt 60 radiation to increase the rate of absorption
- 50% of strength lost by day 5-6
- almost 100% by day 14
- completely absorbed by ~42 days
What are 5 common uses of Vicryl Rapide (Polyglactin 910)?
(skin and mucosa —> quickly healing
- perineal repair
- lacerations
- mucosa in oral cavity
- periocular skin
- skin repairs where rapid absorption may be beneficial (NOT over joints, in body wall or fascia, and in high-stress/tension areas)
How is Polyglactin 910 altered to make Vicryl Plus? When does it completely absorb?
coated with Triclosan, a broad spectrum antibacterial, to reduce bacterial growth at the suture line
56-70 days
What are 6 common times to use Vicryl Plus (Polyglactin 910)?
- contaminated and infected sites
- reproductive tract
- ligation
- general closure
- bowel
- orthopedic procedures
What is the origin and structure of Polydioxanone? What is its tissue reactivity like?
(PDS II vs. PDS Plus)
SYNTHETIC, monofilament
minimal tissue reactivity
When does Polydioxanone completely absorb?
180 days (6 months), usually between 180-210
What are 5 common uses of Polydioxanone?
- soft tissue approximation
- fascia closure
- blood vessel anastomosis
- orthopedic procedures
- tissues that require long-term strength (linea alba, bladder)
What is another name for Polyglecaprone 25? What is its origin and structure? What is its tissue reactivity like?
Monocryl (Plus)
SYNTHETIC monofilament with a high initial strength
minimal tissue reactivity
What is the absorption of Polyglecaprone 25 (Monocryl) like?
- 70-80% strength loss at 14 days
- complete absorption ~100 days (90-120 days)