- 1 Desired Properties Required For Medical Textile
- 2 Classification of Medical Textiles
- 2.1 1. Non-implantable Medical Textiles
- 2.2 2. Implantable Medical Textiles
- 2.3 3. Extracorporeal Devices
- 2.4 4. Hygienic & Health-care Products
- 2.5 Surgical Masks –
- 2.6 Related
Medical textiles definition is, “The textile material and products that have been engineered to meet particular needs suitable for the medical and surgical application, where the combination of following properties are required.”
- Moisture absorbing capacity.
- Air permeability.
These materials are used in contact with tissues, blood, cells, proteins & any other living substances, so that these materials may be ceramic, polymers, natural fibers, metal & composite.
Desired Properties Required For Medical Textile
A medical textile product should have following properties.
- It should be non-toxic.
- It should be non-carcinogenesis.
- It should be non-allergic.
- It should possess the ability to sterilized (radiation, dry heat, boiling).
- It should be chemically inert.
- It should be biocompatible.
- It should have following mechanical properties.
Classification of Medical Textiles
Depending upon use of medical textile products they are classified as follow-
- Non-implantable medical textiles.
- Implantable medical textiles.
- Extracorporeal medical textiles.
- Healthcare & hygienic medical textiles.
These can be discussed in briefly as follow-
1. Non-implantable Medical Textiles
This is used for external application on the body with or without skin contact. This is used for protection against infection, absorption, and exudation of blood & excess fluids, healing applications etc. The requirements from these fabrics are-
- It should be soft & pliable.
- It should protect from further injury.
- It should be easily applied and removed.
- It should be sterile, lint-free and non-toxic.
This includes the wound care products which are usually made in 3 layers-
- Wound contact layer.
- Absorbent layer.
- Base material.
The wound care products are like gauzes, crepe bandage, bed linens, etc.
The gauges are manufactured from cotton in the form of plain weave which has –
EPI- 12 to 20
PPI- 8 to 15
WARP COUNT- 44 Ne
WEFT COUNT- 54 Ne
Gauzes are mainly used as dressing for direct wound but it is also used as internal pads etc. The crepe bandage is successfully used in orthopedics for temporary plastering. Also, it is used in the curing of ‘venous leg ulcer’ for this disease. There is no medicine available only proper bandaging is only technique to cure this disease.
A bamboo fabric is a natural antimicrobial material, this can be successfully used in hospital bed linens. The asthma patients shed their skin in the winter season. This skin contains some microorganisms which are harmful if in held. If the bamboo fabric is used as bed covers and bed linens then this fabric will naturally destroy them (sterilize).
2. Implantable Medical Textiles
Implantable medical textile materials are those which can be implanted in the human body. Those may be bio-absorbable or not bio-absorbable. The examples are as follow-
Sutures are mono or multifilament threads that are used to close wounds, join tissues and tie off bleeding vessels. Suture materials are classified as absorbable & nonabsorbable sutures.
Initially, sutures are made of silk filament which is of nonabsorbable type. Whereas absorbable sutures include ‘Collagen (cadged), Poly glycerin Acid, Polylactic Acid, polycarbonate copolymers etc. This is also used for internal healing.
b) Soft Tissue Implant
This includes biomaterials used in soft tissue, artificial skin, tendons, cornea etc.
The textile material offers strength & flexibility to replace tendons, ligaments & cartilage in construction and corrective surgery. It fills structure of ligament which connects bone to bone & muscle to bone. Textiles are used because they are composed of multiple fibers or fiber bundles. Manmade tendons have been made of woven and braided structures coated with silicon. Requirements for soft tissue implant-
- Tissue compatibility.
- Tensile strength.
c) Hard Tissue Implant
Hard tissues are made of compatible materials that should have excellent mechanical properties. The properties required are-
- It should have good processability.
- It should be chemical.
- It should be biocompatible.
Applications of hard tissue implant are artificial bones, bone cement, artificial joints, etc.
The current practice of manufacturing artificial bones includes ceramic with polymers or certain metals, nowadays orthopedic surgeon uses materials manufactured from Ultra High Molecular Weight Polyethylene because its strength is ten times than steel and having density 0.91 i.e. 7 times lighter than steel. Also, this material is inert in all chemicals.
d) Vascular Veins
Artificial veins or arteries are used to replace segments of a natural cardiovascular system that are blocked or weakened. Grafts are inserted to bypass the blockage and restore blood circulation. The most widely used fibers are polyester, PTFE (Poly Tetra Flora Ethylene).
e) Biomaterial In Ophthalmology
Natural & synthetic hydro-gel physically reassembles the eye tissue and hence used in eyes as soft corneal contact lenses are made of transparent hydro-gel with high oxygen permeability. The lens material should have high surface energy and should be easily wettable by tears. The permeability to oxygen is very important.
f) Dental Biomaterial
Since regeneration of the teeth, the tissue is not possible so biomaterials are used in dental treatment. Requirements of dental polymers are –
It should have-
- Good stability.
- good abrasion resistance.
- Insoluble in oral fluids.
- High softening point.
- Easy fabrication & repairs.
3. Extracorporeal Devices
Textile materials are used in a mechanical organ such as artificial kidney (dialysis), artificial livers, artificial lungs (blood oxygenation) for blood purification are called as extracorporeal devices.
a) Artificial Kidney (Dialysis)
In the dialysis machine, the blood is circulated through a membrane that retains unwanted waste. The membrane may be a flat sheet or bundle of hollow regenerated cellulose fibers. Multilayer fabrics made up of needle punched fabric with different density are also used here.Blood purification is an effective therapy for kidney failure patient. It is used to correct abnormality of blood quality and quantity in treating the sickness.
b) Mechanical Lungs
Mechanical lungs are micro-porous material that provides high permeability for gas flow & low permeability for liquid flow, which is similar to natural lungs where oxygen and blood come into contact with each other. In this device, oxygen flows around hollow fibers at extremely low pressure, blood flows inside the fibers.
The oxygen permeates through micro-porous of fibers & comes into contact with the blood. In this way, the artificial lungs oxygenate the blood. Hollow fibers are also used in artificial liver & pancreas organ cells are placed around the fibers & blood flows inside the fibers.
4. Hygienic & Health-care Products
The purpose of the protective health-care garment is to protect health care professionals from contamination by blood & other infection fluids. This product includes operating & emergency room textile caps, gowns, barrier products, breathable membranes masks etc. The requirements from medical protective textiles are
- It should prevent infective material from passing through the skin.
- It should last long enough.
- It should be affordable.
- It should be comfortable.
- It should be effective.
Fluid resistance clothes should be one if there is a chance for splashing or spraying of blood or other fluids which will protect the medical professionals. The impact of AIDS such diseases has made hospitals cautious about protective fabric. The medical professionals were once mainly concern with protecting patients but today they give priority to protecting themselves from such diseases.
Commercial BAR BAR 1+ is a P/C (50/50)woven fabric used for this purpose. It is durable, static control, it provides comfort to the wearer. It also has properties such as abrasion resistance, tensile strength, fast surgical masks drying & reusable.
CORETEX is a 2 layer fabric used as a barrier material. It is mainly used as surgical fabric. This type of coating makes the fabric breathable yet liquids proof.
Surgical Masks –
Surgical masks are made of 3 layers. The middle layer of extra fine glass fiber or synthetic microfibers. The other two sides are made with acrylic bonded parallel laid or wet laid non-woven fabric.