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FIBRES AND SURGICAL
DRESSINGS

FIBRES
• DEFINITION
• Fibres are minute hair-like or thread-like
substances, which are of natural or synthetic
origin
...

• Fibres and the surgical dressing they produce
are of Immense importance in medicinal and
pharmaceutical practice
...

• They are polymers of various types

Fibres
Natural

Regenerated

Synthetic
1
...
Terylene

Plant Fibres

Animal Fibre
1
...
Silk

Cellulose wadding

Rayons
1
...
Viscose
3
...
Cotton

Ploem Fibre

Pericyclic Fibres

1
...
Flax
2
...

• Geographical source: Gossypium species are cultivated for
commercial production of cotton in the United States of America,
West Indies, Peru Brazil, India, China and Egypt
...


• Preparation of Raw Cotton and Absorbent Cotton
Wool:
• Bolls of cotton are collected from the ripe and dehisced
fruits of Gossypium
...

• The masses of these separated trichomes constitute
Raw Cotton
...
6 per
cent of wax and oil, which form a thin film around the
fibres and render them non-absorbent
...


Absorbent Cotton Wool
• Absorbent Cotton Wool is prepared from the
various cotton wastes obtained during the
processing of raw cotton for making yarns
...

• This treatment removes the fatty cuticle and
renders the trichomes absorbent
...

• The bleached mass of fibres is then dried,
loosened, 'scutched‘(beaten) and carded by using
appropriate machines
...

• Several such films are superimposed on one
another and rolled
...

• Absorbent cotton wool is more white than the
raw cotton, which has a brownish tint
...

• When placed on the surface of water raw cotton
floats while absorbent cotton rapidly sinks
...
The apex is rounded
...

• When treated with ammoniacal copper oxide
solution (cuoxam) raw cotton fibres dissolve with
ballooning, while those of absorbent cotton
dissolve with uniform swelling
...
Absorbent cotton is almost pure
cellulose
...
It is also used as a
filtering medium and an insulating material
...
It is one of the cheapest plant fibres in the market
and is second only to cotton in the amount produced and in the
variety of uses
...

• Synonym: Gunny
• Biological source: Strands of phloem fibres of the stem bark of
Corchorus olitorius Linn, and C
...

• Family; Tiliaceae
...
It is also cultivated in small quantities in some
parts of India
...
They are cut from the base
when the plants are in flower
...

• The stacks are covered with straw or water hyacinths to
keep them wet and to -protect from direct sunlight
...

• The fibres are then dried in direct sunlight and
made into small bundles
...


Macroscopical and Microscopical
characters
• The strands of Jute are pale buff or silvery grey in colour, 1
to 3 m long and about 30 to 140 µm in diameter somewhat
coarse in texture
...

• The individual fibres vary from 0
...
0 mm in length and
10 to 25µm in diameter, with a quite smooth surface
...

• The ends of the fibres are rounded and-blunt
...

• They are insoluble in 80 per cent sulphuric acid
• stain red with phloroglucinol and hydrochloric acid
...

• Uses: In pharmacy Jute is used for the manufacture of
medicated tows (pieces of fibre), for padding splints
...

• They can be used to make curtains, chair coverings and
cloths
...

• Geographical source: Flax is prepared commercially in Russia,
Northern Ireland, U
...
A
...


• Preparation of Flax: The plants are uprooted by hand just about the
time of opening of the fruits, tied in bundles and left to dry in the
field
...

• When retting is complete, the stalks are dried in the sun, then
broken into pieces in a mill and the pieces of the xylem tissues
(pericyclic fibres) removed by the teeth of a 'scutcher'
...

• They are about 50 cm in length
...


CELLULOSE WADDING
• Synonyms: Wool Cellulose, Chemical Wood Pulp
• Biological source: cellulose wadding is prepared from
wood pulp bleached with sulphite
...

• Family Pinaceae
...
S
...
Canada and Germany
...

• Uses: uses of cellulose wadding are similar to
those of absorbent cotton wool
...


RAYON
• Synonyms: Regenerated cellulose, artificial silk
• Biological source: Rayons are prepared from the
polysaccharide cellulose molecule derived from wood pulps
by maceration and treatment with various chemical
substances
...

• Out of these Viscose rayon is mainly used for surgical
dressing purposes
...

• Its tensile strength is much less than that of cotton
...

• Viscose rayon gives cellulose test with N/50 iodine
solution and 80 per cent sulphuric acid (blue colour)
...


• Constituents: like Cellulose wadding, Viscose
rayon is also composed almost entirely of
cellulose
...
03 per cent
of sulphur and yields about 0
...
3 per cent
of ash
...


WOOL
• Synonyms: Animal Wool, Sheep's Wool
• Biological source: Wool consists of the hairs of the fleece of the
sheep, Ovis dries Linn
...

• Geographical source: Wool is produced and exported by the U
...
A
...

• Preparation of wool: The hairs are cut from the sheep at
appropriate intervals and dirts removed by beating on a sieve
screen
...
The wool is then bleached with
sulphur dioxide or hydrogen peroxide, thoroughly washed and dried
by hot air on wire netting
...

• When pulled, a wad of wool separates out with
considerable resistance due to the clinging nature of
the hairs
...

• A darker coloured narrow band is present along the
central axis of the hairs
...
They are insoluble in 80%
sulphuric Acid
...

• Wool fibres and their yarns are of immense
commercial value for their use in the textile
industries for manufacturing warm fabrics
...

• Family; Bombycidae
• Geographical source: Silk is cultivated in
Japan, China, France and Italy
...


• Preparation of silk: The cocoons, a covering of filaments
produced by the larvae of the silkworm around themselves
before passing to their pupal stage, are collected
immediately after the larvae reach the pupal stage
...
The
cocoons are then placed in hot water to soften and to
remove partly the natural gum of the silk filaments
...

• A number of these are twisted together to form a single
thread of raw silk
...


Macroscopical and microscopical
characters
• Silk consists of very fine, soft, smooth and solid
threads, usually yellow in colour
...

• Under the microscope, silk appears as cylindrical
or slightly flattened, solid threads, 5 to 25 µm in
diameter
...


• Constituents: The mass of the silk fibre is
made up of the protein fibroin, coated
externally by another protein sericin or silk
gum, which cements the fibres together
...

• Uses: the pharmaceutical use of Silk include
the manufacture of ligatures
...
The poly-condensation product in
molten condition is pumped through a spinning machine
and the resultant filaments are cold-drawn to increase their
length
...

• In cross sections they appear uniformly circular
...

• The filaments are very strong in their tensile strength
...


• Nylon fibres do not respond to any chemical
tests which are used to identify vegetable,
animal or regenerated fibres
...

• Uses: In surgical dressings Nylon is used for
making non-absorbable sutures
...


Surgical dressing
• Surgical dressing is a general term applied to
various fibrous materials used for scientific
and hygienic management of wounds and for
providing sufficient protection to the exposed
tissues
...
made from
them
...

• The groups of various types of surgical
dressings may be summarised as follows:

Surgical Dressing

Gauzes

Bandages

Lints

Plasters
Standard dressing

• Common fabric made from fibres forms the
basic materials for the preparation of most of
the above surgical dressings
• The thickness of the yarn/ Thread and the
type of the weave of the fabric vary with the
type of the surgical dressings to be made
...

• They can be either medicated or
unmedicated
...


• Gauzes used for surgical dressings may be
conveniently grouped as follow:
GAUZES

Unmedicated:
1
...
Absorben Ribbon Gauze
3
...
Cellulose tissue

Medicated:
1
...
Euflavine Gauze
3
...
Iodoform Gauze
5
...
Capsicum Tissue

UNMEDICATED GAUZES
• Absorbent Gauze: this gauze consists of a plain
wove cotton fabric 36 inches wide,
(1inche=2
...
One
square yard (1yard= 91
...
6g (Standard Thread size=
0
...
A 2 by 6
yards of the gauze weighs not less than 12
...


• Absorbent Gauze Tissue: this is a sleeve like
(tubular) absorbent gauze which encloses a thick
layer of absorbent cotton wool
...
One
pound (1pound=453
...

• Cellulose Tissue: this is also tubular absorbent
gauze like the Gauze tissue
...
Other specification are similar to
those of Absorbent Gauze Tissue
...
They include the following:
• Boric Acid Gauze: this gauze contains 3 to 7% of Boric
acid and is tinted pink with a suitable dye
...
1% of
Euflavine (antiseptic activity, treatment of burns)
• Double Cyanide Gauze: This contains a mixture of
Mecury cyanide (0
...
5%) and Zinc cyanide (1
...
0%) and is tinted purple with suitable dye
...
(removes
damaged tissues)
• Trinitrophenol Gauze: it contains 1
...
5%
of trinitrophenol
...
(antiseptic)

BANDAGES
• Bandages are continuous length of fabrics and
contain no joints
...

Bandages are chiefly made from plain or
treated cotton cloths, but some of them are
also made from wool
...


BANDAGES

Plain Cotton
Treated Cotton
Cloth Bandage
Cloth Bandage
1
...
Batiste
2
...
Jaconet
3
...
Oiled Cambric
bandage
4
...
Muslin Bandage

Wool
Containing Bandage
1
...
Domette Bandage
3
...
Oiled Silk Bandage

Plain Cotton cloth Bandages
• Open-wove Bandage: This is a white bandage which
contains not less than 43 threads per inch in the warp and
27 in the weft
...
96 g
...
A 2 in by 4 yd bleached calico bandage weighs
not less than 13
...

• Unbleached Calico Bandage: This bandage contains 65
threads per inch in the warp and 60 in the weft
...
2 g
...
It contains 48 threads per inch in the warp and 30 in
the weft
...
25 g
...
They may be medicated or unmedicated
...

• Jaconet: This is also a bleached fabric like Battiste, but it is
waterproofed only on one side with rubber
...

• Zinc paste Bandage: It is a bleached open-wove bandage,
impregnated with a zinc oxide paste
...
They include the
following bandages:
• Flannel Bandage: This consists of wollen
fabric, the threads of which have been raised to
form a nap
...
A 2 in by 6 yd flannel
bandage weighs not less than 58
...

• Domette Bandage: It is made up of a mixed
fabric, which contains cotton threads in the warp
(not less than 40 per inch) and woolthreads in the
weft (not less than 22 per inch)
...
5g
...

• However, it contains not less than 33
...

• When fully extended, the bandage must measure not
less than twice the length of its unstretched condition
...

• Crepe means wrinkled

Silk Bandage
• Silk fabrics are used to prepare some special type
of surgical dressings
...

• The bandage is rendered completely waterproof
by treating the fabric with a suitable drying oil or
an oil-modified synthetic resin
...


LINTS
• Lints are medicated or unmedicated absorbent
surgical dressings
...

• The threads in the warp of the lint-fabrics are
raised to form a nap
...

• 230 to 250 sq inch superficial area of the lints
should weigh about 28
...


• The following medicated lints are available:
• 1
...

• 2
...
1 per cent of euflavine
...

• An adhesive compound is spread on one side
of the bandage to make it stick to the skin
...


• Some common plasters include the following:
• Rubber Adhesive Plaster: This is a bleached cotton fabric of
prescribed standard, prepared with an adhesive compound
spread on one side and waterproofed with rubber on the
other side
...
(skin infections)
• Elastic Adhesive Plaster: This consists of medicated elastic
cotton fabric, spread with an adhesive compound which
also contains 20 to 30 per cent of Zinc oxide
...
This bandage is impregnated with at least 80 per
cent of exsiccated calcium sulphate
...

• These dressings are prepared ready for use
and consist of a pad of medicated cotton
wool, gauze or lint stitched to an open-wove
bandage at certain distance from one end
...
P
...
are numbered 1 to 15 and
variously named as follows:
• Standard Dressing No
...

• Standard Dressing No
...

• Standard Dressings No
...
All of them consist of a pad fixed centrally to a fleshcoloured elastic cotton fabric with an adhesive margin all round
...


• Standard Dressings No
...
They consist of a Boric
acid lint, superimposed on Absorbent cotton wool and
attached to an open-wove bandage
...

• Standard Dressings No
...
These dressings are similar to the
Medicated wound dressings, but their pads are made of
Euflavine lint instead of Boric acid lint
...

• Standard Dressings No
...
They consist of a pad of Absorbent cotton
wool, enclosed in Absorbent gauze and attached to an
open-wove bandage

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