Suture Materials Classification Notes

Suture Materials Sutures

Suturing is a technique of uniting parts of the body by stitching them together and the materials that we use are called sutures.

Ideal Suture Material

• Sterile
• All-purpose (composed of material that can be used in any surgical procedure)
• Causes minimal tissue injury or tissue reaction, i.e. non-electrolytic, noncapillary, nonallergenic, noncarcinogenic

Read And Learn More: Clinical Medicine And Surgery Notes

• Easy to handle
• Holds securely when knotted, i.e. no fraying or cutting
• High tensile strength
• Favorable absorption profile.

Ideal Suture Material Classification

Absorbable

1. Natural
   1. Catgut
   2. Tensor fascia lata
   3. Collagen tape
2. Synthetic
   1. Polyglycolic acid—Dexon
   2. Polyglactin—Vicryl
   3. Polydioxanone—PDS

2. Nonabsorbable

1. Natural
   1. Linen
   2. Cotton
   3. Silk
2. Synthetic
   1. Nylon
   2. Terylene—Dacron
   3. Polypropylene—Prolene
3. Staples

Ideal Suture Material Properties

• Absorbable or non-absorbable
• Tensile strength: It increases with the diameter of the suture material.

Other Properties

• Biological
  • Catgut, silk, cotton
• Man-made
  • Polyester, polyamide, polypropylene
• Monofilament
  • Polyamide, polypropylene, catgut, PDS
• Multifilament
  • Silk, cotton, polyamide, etc.
• Braided
  • Silk, Polyamide
• Twisted
  • Cottom
• Coated
  • Polyamide, prolene, catgut
• Uncoated
  • Cotton, polyester

 

• Smoothness: Easy passage through the tissues—Monofilament—such as Prolene is
  preferred in vascular surgery.
• Filament arrangement: Monofilament or poly filament: Twisted, braided or
  flossed.
• Requires multiple knots.
• Silk.

Filament Arrangement

• Monofilament: Infection rates are less, but the knot may slip due to the smooth surface. No fraying of the end on cutting.
• Polyfilament: Because of crevices, infection rates are high. Knotting is good because of a rough surface. There is fraying of the end on cutting.

Details Absorbable

1. Catgut

This is the oldest suture material and is derived from the submucosa of sheep intestines.

Origin of the word catgut

• The original word was kitgut (“Violin string”), kit meaning “fiddle,” and the present form has arisen through confusion with kit = cat.
• Another explanation of the origin of the cat in catgut is that it is an abbreviation for cattle which originally denoted not only cows but all types of livestock.
• It is available in two forms. Plain catgut which gets absorbed within 7–10 days. With the addition of chromic salts, it becomes harder and it is called chromic catgut. It gets absorbed within 20–25 days.

Plain catgut

• This is procured from the submucosa of the small intestine of the sheep. It has rich elastic tissue
• Tensile strength is lost in 7–10 days
• Knotting property is not good
• Absorbed in a week — Superrfical tissue suturing or cutaneous blood vessels, etc.
• Should not be boiled or autoclaved
• Preserved in formaldehyde plus denatured absolute alcohol solution.

Chromic catgut

• Plain catgut is treated with chromic salts to delay the hydrolysis by the body
  20% chromic acid solution with 5 parts of glycerine
• Chromic acid not only sterilises the suture but also acts as a preservative
• Available in aluminium-coated sterile foil with preservative
• Absorbed in 20 days—used to apply deep sutures.
• Available as 1–0 (thickest) to 6–0 (thinnest).

Chromic catgut Uses

• Suturing the tongue and lips
• Intestinal sutures
• Suturing of fascia.

Chromic catgut Advantages

It gets absorbed due to enzymatic digestion. Hence, sutures need not be removed. It has good knotting properties.

Chromic catgut Disadvantages

• It cannot be used in the presence of infection.
• Tissue reaction is more with chromic catgut.
• It becomes 30% loose within 28 days.

2. Polyglycolic Acid (Dexon)

• It is synthetic absorbable suture material and gets absorbed within 60–90 days. Dexon is inert, with good knotting properties.
• Synthetic absorbable
• White in colour
• Absorption time—100 days
• Can be used in the presence of infection as it is absorbed by an esterase enzyme system
• Better knot holding as it is braided
• Used for intestinal, biliary anastomosis, ligation of vascular pedicles, etc.

3. Polyglactin (Vicryl)

• It is twice as strong as catgut. One of the advantages of vinyl is the tissue reaction which is the least. This suture material can be used for intestinal anastomosis. It loses its half-life within 14 days.
• It holds its tensile strength for approximately three to four weeks in tissue. Vicryl may also be treated for more rapid breakdown in rapidly healing tissues (Vicryl Rapide), or impregnated with triclosan to provide antimicrobial protection of the suture line (Vicryl PLUS).

Polyglactin (Vicryl) Properties

• Synthetic absorbable
• Polyglactin
• Co-polymer of glycolide and lactide
• Poly filament braided
• Violet colour (visible at depth)
• Size (7–0 to 1–0)
• Good tensile strength and knotting properties
• Disintegrated by hydrolysis (less tissue reaction)
• Lasts for 10 weeks
• Widely used intestinal anastomosis, and pedicle ligation.

4. Synthetic Absorbable—PDS

• Polydioxanone suture
• Delayed absorption—total 240 days
• 70% tensile strength remains after 20 days
• Minimal tissue reaction
• Intestinal anastomosis, etc.

Nonabsorbable

1. Silk

• Non absorbable (Natural)
• Poly filament
• Obtained from Cocoon of Silkworm
• Size 2 to 8–0 (thinnest), black in colour
• Available as braided (braided and coated with wax to reduce capillary action) or twisted
• Available as eyeless needled sutures (atraumatic), stuck-sterile foil with silk without needle, reels-autoclaved
• Do not boil
• Never becomes brittle, ties smoothly, cheap, good for optimum knotting Silk is better than thread.
• It can be widely used in various intestinal anastomoses, ligatures of vessels, etc.
• It has excellent knotting property
• However, silk produces more tissue reactions because it is a foreign protein.

2. Polyamide (Sutupack)

• It is nonabsorbable and its tensile strength is good.
• However, it has poor knotting property.
• It can be used to close the peritoneum and abdominal layers (linea alba, rectus sheath).

3. Nylon

• Non-absorbable—synthetic, cheaper
• It is monofilament, and blue in colour, and can be used to suture in the presence of infections.
• Thickness is 1–8
• Less irritant, high tensile strength
• Slippage of the knot can occur with nylon because it is too smooth. Hence, 5–7 knots should be put.
• Infection in braided nylon can occur
• For skin sutures monofilament and for hernia repair braided nylon is used.

4. Polypropylene (Prolene)

• It is a nonabsorbable suture material which can be used like polyamide.
• It is inert, monofilamentous, (no infection) available as 10–0 to 2.
• It has good knotting properties superior to nylon.
• Inert, resist breakdown
• Smooth, easy to tie, less thrombogenic— used in vascular and plastic surgery Prolene mesh is available to treat inguinal hernia or incisional hernia.
• Tensile strength lasts for many years
• Sky blue in colour.

Prolene for vascular sutures

• Exceptionally smooth
• Prolene is exceptionally smooth enabling it to pass very easily through tissue. Prolene does not snag on vessel adventitia and the tension on a continuous stitch can be easily adjusted after the suture line has been placed.
• Prolene retains its tensile strength in tissue many years after implantation. It flexes with the mechanical action of pulsatile tissue and resists fatigue-induced fracture knots securely.
• Memory-free, minimal tissue reaction.

5. Linen or Cotton

• Non-absorbable (Natural)
• Linen—made from jute fibres, a material of vegetable origin
• Twisted poly filament
• Size 2 thickest, 8–0 thinnest
• Cheap, freely available
• Tissue reaction is more
• Tensile strength is less
• Absorbs fluids by capillary action—more chances of infection
• Can be used for transfixion of hernial sacs and skin closure.
• It is very cheap.

Non-Absorbable-synthetic

• Stainless steel wire: Little tissue reaction, interdental wiring—fracture patella— as bone suture, closure of sternotomy incision.
• Polyamide: Monofilament, black in colour, minimal tissue reaction, smooth-subcutaneous sutures can be applied. Used for laparotomy wound closure.