A surgical suture is a thread or sting used for sewing or stitching together tissues, muscles, and tendons with the help of a needle. If these threads or fibres are used to tie a blood vessel to stop bleeding without the use of a needle, then they are digested in animal tissues.
SUTURES AND LIGATURES
A surgical suture is a thread or sting used for sewing or
stitching together tissues, muscles, and tendons with the help of a needle. If
these threads or fibres are used to tie a blood vessel to stop bleeding without
the use of a needle, then they are digested in animal tissues,for example,
catgut, kangaroo tendon, and synthetic polyesters. If the sutures are not
absorbed in the body, they are called nonabsorbable sutures, for example, silk,
cotton, nylon, synthetic polyester fibres and stainless steel wire. A good
quality of suture should be well-sterilized, nonirritant; having
well-mechanical strength, fine gauze and with minimum time of absorption.
Absorbable Sutures
Surgical
catgut
Catgut is a sterilized fibre or strand prepared from
collagen of connective tissues obtained from healthy animals like sheep and
cattle.
Preparation
The submucosal layer of small intestine of a freshly killed
animal is used for the preparation of catgut. About 7.5 m long intestine is
cleaned and split longitudinally into ribbons. The inner most mucosa and two
outer layers of submucosa, muscularis, and serosal layers, are removed with the
help of a machine leaving behind the submucosa. Up to six such ribbons are
stretched, spun and dried to form a uniform strand. These fibres are polished
to get smooth strings, gauzed for their diameter, cut into suitable lengths and
sterilized by placing the catgut in glass tubes filled with anhydrous
high-boiling liquids like toluene or xylene and then heating in an autoclave.
Sterilization may be done by irradiating the suture by electron particles or by
gamma rays from cobalt-60.
Kangaroo tendons, used in hernia and bone repairs, are
prepared from the tails of kangaroo by the identical method adopted for the
preparation of catgut, Chromicized surgical catguts are prepared by soaking the
ribbons in solutions of chromium salts for tanning the tissues. These fibres
are not affected by proteolytic enzymes in the body and they are not absorbed
rapidly in the body.
Synthetic
polyesters
The polymers obtained by condensation of cyclic derivatives
of glycolic acid (glycolide) with cyclic derivatives of lactic acid (lacticide)
are used to prepare synthetic absorbable sutures. These sutures have high
tensile strength and are degraded by hydrolysis and absorbed in the tissue.
Nonabsorbable Sutures
Nonabsorbable sutures are not affected by the body fluid and
remained unchanged for a long period. They are removed after healing of the
wounds. Silk, cotton, nylon, and metallic sutures are classified as
nonabsorbable sutures.
Silk
sutures
Silk sutures are prepared by spinning or twisting silk
fibres into a single strand of varying diameters. The sutures are smooth and
strong and braided by combining several twisted yarns into a compact mass. The
strands are sterilized and boiled with water to soften them.
Cotton
sutures
Cotton sutures have uniform size and recommended in critical
parts where strength of the sutures is required for long time.
Nylon
sutures
The microfilaments of nylon are braided into strands of
required diameter. These sutures are strong, water resistant, and used in skin
and plastic surgery.
Linen
suture
A linen suture is cheap, very strong under moist condition
but not uniform in diameter.
Metallic
sutures
Metallic wires of silver or stainless steel are used as
surgical aid. These wires are available as mono-filaments, twists, and braids.
TH 2019 - 2023 pharmacy180.com; Developed by Therithal info.