Suture Material

Question 1

What are absorbable sutures?

Answer 1

Sutures that lose their tensile strength within 60 days

Question 2

What are non-absorbable sutures?

Answer 2

Sutures that are permanent

Question 3

What is natural suture material?

Answer 3

Made from animal or plant tissue that has antigenic properties

Question 4

What is synthetic suture material?

Answer 4

Man-made material

- Chosen for its inert character

Question 5

What 12 qualities should the ideal suture material have?

Answer 5

1. Maintain adequate tensile strength
2. Stimulation minimal inflammation
3. Discourage bacterial growth
4. Non-capillary but predictable absorbable
5. Non-electrolytic
6. Non- allergenic
7. Non- carcinogenic
8. Good Handling properties
9. Good knot security
10. Inexpensive and readily available
11. Easily sterilised and able to be re sterilised
12. Monofilament

Question 6

Quality of maintaining adequate tensile strength…

Answer 6

• Tensile strength affects the tissue’s ability to withstand injury but isn’t related to length of time it takes the tissue to heal
• Suture chosen should at least as strong as the tissue

Question 7

Quality of stimulating minimal inflammation..

Answer 7

Natural materials provoke inflammation and potentially immune response
- Absorption by phagocytosis which leads to granulation tissue and scarring

Synthetic Materials are designed to be minimally inflammatory
- Absorption mainly by hydrolysis

Question 8

Quality of discouraging bacterial growth…

Answer 8

Monofilaments less likely to collect bacteria when they are dragged across the skin
- Multifilament weaves trap bacteria

• Any suture material acts as a trap for infection which lowers the number of bacteria required to establish infection
• Some suture material has antibacterial coatings
• • these can actively reduce infection risk

Question 9

Quality of non-capillary but predictably absorbable…

Answer 9

• Capillary suture material “wicks” liquids

- Absorbable sutures should degrade as predicted, and be unaffected by the presence of infection

Question 10

Quality of non-electrolytic…

Answer 10

I.e. inorganics such as stables should be made out of material that doesn’t rust or cause electrolysis

Question 11

Quality of non-allergenic…

Answer 11

Won’t cause a reaction e.g. welts or a whole body reaction

Question 12

Quality of non-carcinogenic…

Answer 12

Non cancer causing

Question 13

Qualities of good handling skills and good knot security…

Answer 13

Suture material needs to be pliable so knots can be formed

Memory is the tendency for the material to kink or spiral when stressed and maintain the new shape after stress is removed

Question 14

What type of suture materials tend to have the best memory?

Answer 14

Monofilaments

Question 15

What type of suture materials tend to return to their pre-stressed state?

Answer 15

Multifilaments

Question 16

What type of filaments have the best knot-holding characteristics?

Answer 16

Multifilaments

Question 17

What is an advantage and disadvantage of coating suture material?

Answer 17

Adv:
Reduces tissue drag i.e. friction causes trauma

Disadv:

• Requires more tension to ensure good tissue apposition
• Reduces knot- holding

Question 18

Describe braided multifilaments…

Answer 18

They are made from several primary strands spun together

• Wick fluid and trap bacteria in gaps between strands

Question 19

Describe catgut suture…

Answer 19

Made from sub-mucosa of sheep or serosa of cows

• Three strands spun together then polished to form a virtual monofilament

Question 20

Describe chromic catgut suture…

Answer 20

Made from sub-mucosa of sheep or serosa of cows
- treated with Chromic sales to slow absorption

• A virtual monofilament
• Tensile strength: 21-28 days
• Absorbed normally around 90 days

Question 21

Describe silk suture…

Answer 21

Natural protein fibre of raw silk spun by silkworms

• Braided and dyed

Question 22

Describe polyester braided suture…

Answer 22

• Indefinite wound support
• Less tissue reaction than silk
• Handles and ties securely

Question 23

Describe Nylon suture…

Answer 23

• Monofilament
• Loses about 10-15% strength per year
• Takes up fluid

Question 24

Describe USP suture sizing…

Answer 24

7 is the largest
12/0 (12/ zero) is the smallest
- i.e. size 000000000000 is finer than 2/0 which is 00

• As the number of zeros increases, the diameter of the suture decreases

Question 25

What principle should you use to select your sutures on?

Answer 25

The principle that different tissue have differing requirements for suture support, and they heal at different rates

Question 26

What is important about tissues strengths?

Answer 26

There are regional and species differences - related to the collagen layers of the organ and the submucosa i. e. duodenum is strong and the bladder is weak

Question 27

What is important about suture materials and their correlation with tissue healing rates?

Answer 27

A suture must last at least as long as, but not too much longer, than the time the tissue takes to heal

Question 28

What kind of suture should you choose for rapidly healing tissue?

Answer 28

- One that will lose it's tensile strength at about the same rate as the tissue gains strength - And one that will also be absorbed

Question 29

What rule should be applied when selecting suture size?

Answer 29

Use the smallest diameter suture that will adequately hold the mending wounded tissue Suture no stronger than the sutured tissue

Question 30

What are the needle types?

Answer 30

- Needles with eyes | - Needles with swaged on suture

Question 31

What is the advantage of a swaged needle?

Answer 31

- Follows directly through the hole made by the needle

Question 32

What is the disadvantage of a swaged needle?

Answer 32

Added cost | - Should be handed to the client so it doesn't cost the practise

Question 33

What is the advantage of an eyed needle?

Answer 33

Allows reel suture to be used which reduces cost

Question 34

What is the disadvantage of a swaged needle?

Answer 34

Suture material may fall out of the eye

Question 35

Describe the advantages of DIY swaged needles?

Answer 35

- Cheap - Readily available - Very sharp - Good in the field for large animals

Question 36

Describe the disadvantages of DIY swaged needles?

Answer 36

- Fiddly threading - Can traumatise suture when threading - Sometimes pulls out of the needle

Question 37

What are straight needles used for?

Answer 37

- GIT - Nasal cavity - Nerves - Oral cavity - Pharynx - Skin - Tendons - Vessels

Question 38

What are half-curved needles used for?

Answer 38

- Skin (rarely used) | - Laparoscopy

Question 39

What are 1/4 circle needles used for?

Answer 39

- Eye | - Microsurgery

Question 40

What are 3/8 circle needles used for?

Answer 40

- Aponeurosa - Biliary tract - CV system - Dura - Eye - GIT - Muscles - Myocardium - Nerves - Periosteum - Pleura - Skin - Tendon - Urogenital tract - Vessels

Question 41

What are 1/2 circle needles used for?

Answer 41

- Biliary tract - CV system - Eye - Fascia - GIT - Muscle - Nasal cavity - Oral cavity - Pelvis - Peritoneum - Pharynx - Pleura - Skin - Tendon - Sub cut fat - Urogenital tract

Question 42

What are 5/8 circle needles used for?

Answer 42

- Anal - Nasal cavity - Pelvis - Urogenital tract

Question 43

What are compound curved needles used for?

Answer 43

- Eye | - Laparoscopy

Question 44

Describe cutting needles...

Answer 44

They have a triangular cross section | - Cut through dense tissue like dermis

Question 45

Describe Taper needles...

Answer 45

Have an O cross section | - Used on less dense tissue like bowel or muscle to avoid tearing more delicate tissue

Question 46

What are some alternatives to sutures?

Answer 46

- Metal staples - Tape suture - Tissue glues

Question 47

What kind of suture material would be suitable for fascia?

Answer 47

- Long-lasting - Absorbable - Synthetic - Mono-filament e.g. PDS or Maxon size 1 or 0

Question 48

Why is it that we can't use the best suture and needle every time?

Answer 48

1. Cost | 2. Availability in practice