What are Isolation Gowns and where are they used?

Introduction

Isolation gowns are mainly used in hospitals and health care organizations to safeguard themselves from hazardous infections. It protects the wearer from infected persons who come nearby or in contact with them. It also helps the patients with weak immune system since they are more prone to get infected by the infections.

It protects the medical professionals mainly during surgeries and procedures where liquid and solid materials may get contaminated. It also helps patients during the major surgery such as organ transplantation, spine surgery, etc. The gown should cover all the clothing and the exposed body areas. It is worn by health care personnel during procedures or surgeries to protect themselves as well as the patient from the transfer of microorganisms, bodily fluids and particulate matter. It also helps in treating patients with multidrug resistant bacteria since they may be more prone to the risk of infection.

Gowns are one of the most widely used Personal Protective Equipment (PPE) by the medical professionals. It protects both the doctors and the patients against cross contamination. These gowns are available in both reusable and disposable form. Reusable gowns are made from a variety of fabrics and fibers like cotton, polyester or polyester/cotton blends, but disposable gowns are made up of nonwoven materials and plastic films, which should be disposed properly to prevent infection exposures. It is necessary in patients infected with contagious diseases or infections. Some study shows that gowns are only needed if the patient has lower body injury. It is used for the bedridden patients for their comfort and user friendly type.  Medical professionals use the PPE in order to prevent themselves from exposures to blood, bacterial infections or any other body fluids. Gloves are used when collecting blood samples or when the biomedical specimens such as urine, saliva samples are handled. These are mainly used to protect from any contamination. It is necessary to wear the PPE to protect from body fluids such as saliva, pus, blood, etc.

Specification

Color: White, Blue, Yellow, Orange, Green, etc.

 

Material Type: SMS, SMMS, SMMMS, PP, PP+PE, PE, Polyethylene, Polyester pongee, Polyester taffeta, CPE, etc.

 

Weight: 20-75 g

 

Style and Design: Apron, Reverse wear, Hook and loop, Velcro, Knitted collar, Shirt collar, Round collar, Tie, Coverall, Split type, With or without Pocket, Zip, Pajama, Short, etc.

 

Isolation gowns are available based on their type of material, usage property i.e. disposable or reusable, user friendliness, design of the gown, protection quality associated with the rate of infection control from the parasites and microorganisms, etc.  It protects the health care workers from exposing their body parts while taking care of the patients.

 

Isolation gowns were made of cotton or polyester. Earlier, isolation gowns offered minimal level of protection due to fluid absorption and wide usage of the material led to deterioration. Nowadays, isolation gowns are inexpensive and durable.  It should be worn by the health care workers to protect themselves while taking care of the patients when exposed to bodily fluids, their clothes, etc. Different types of isolation gowns are available in the market providing various levels of protection to the wearer. Isolation gowns are selected based on the care and procedures involved around the patients, based on the level of contact with the infectious material. It should act as the barrier against the penetration of fluids or infections. According to safety standards and measures, isolation gowns are necessary to be worn only when there is contact with body fluids. When taking care of the infected persons, PPE such as gloves and gown both are required to consult and treat them.

 

The gown properties are based on the physical and chemical properties of fibers. Fibers are the smallest unit of fabric used in the gowns. Fabrics consisting of fine and thin fibers as microfibers are used for higher level of protection in the gown. This provides a wide range of protection and acts as the barrier for microbes and infections. Based on the absorbent nature of the fiber, transmission of the fluids is defined for the gown. When the absorbent nature of the fibers is high, liquids get absorbed due to which bacteria gets transmitted. When the absorbent nature is low, liquid will remain on the surface resulting in the capillary movement of liquid. Fibers such as silk, cotton, wool, polyester have higher absorbent property than synthetic fibers. Mostly, isolation gowns are made of polypropylene and polyester.

 

In order to define the transfer of microorganisms, parasites, air, liquids in the fabric material, penetration and permeation are referred. Major flow of liquids or gases through the porous material that is driven by pressure gradient is defined as the penetration. Diffusion of gas, liquid or vapor through the porous materials and nonporous materials is defined as the permeation. Penetration and permeation both can occur through the pores and imperfections in the fabric. Hence, microorganisms can penetrate, but cannot permeate through the fabric due to their size when compared to gas and vapor molecules.

 

Hospital gowns are designed based on the fluorocarbon-based finishes which can repel water and oil based liquids. Fluorocarbon-based finishes can lead to penetration, but this provides the water resistant property. The penetration is due to increase in pressure or by liquids of lower surface tension penetration. The fabric surface repellent property can be increased thereby reducing the surface energy. When the repellent coating is applied on the surface, it gets smoother and shed liquids more when compared to rough surfaces. It is stated that fabric is designed to improve repellency for the prevention of bacterial transmission. When the repellent is applied on the fabric for the prevention of microorganism transmission, it should improve the barrier property to a greater extent.

 

 

Disposable isolation gowns have the following properties

 

• Ease to breath
• Ease to wash and maintenance
• Ease to wear and comfort
• More resistant towards dust and harmful bacteria
• Skin friendliness

 

 

Classification

 

Isolation gowns are classified based on the levels of risks

• Minimal
• Low
• Moderate
• High

Minimal: Used for basic and standard medical use in health care units

Low: Used in Intensive Care Unit, Pathology Lab

Moderate: Used in emergency room for trauma patients

High: Used in major surgeries

 

Reusable versus Disposable Isolation Gowns

There are studies showing that choosing reusable isolation gowns instead of disposable decreases the environmental effect by:

• 28% lower natural resource energy consumption
• 30% lower greenhouse gas emissions
• 41% lower total water consumed
• 93-99% lower solid waste generation at healthcare

Disposable isolation gowns are referred as single use gowns that is designed to be discarded after a single use. It offers protection from liquid penetration due to the presence of nonwoven materials and the materials made of plastic films. They are designed using nonwoven
fiber-bonding technologies in order to provide integrity and strength. Disposable isolation gowns are made of basic raw materials of synthetic fibers such as polypropylene, polyester, polyethylene. Fabrics should meet the desired properties by the use of types of fibers, bonding process, chemical or physical treatment of the fabric.

Reusable gowns can be washed after each time of usage. They are made of cotton or polyester or a combination of both. These fabrics are made of tightly woven plain weave fabrics, pressed through rollers to enhance the liquid barrier properties. Reusable garments can be used after many washing or according to the manufacturer design. Microorganisms may sometimes penetrate the fabric when there is no liquid penetration visible in the material. In the reusable gowns, design made of antibacterial finishes can kill the microorganisms, reduce the transmission of microbes and pathogens.

The design of the gown also plays a vital role in providing barrier property along with the fabric property. Some of the characteristics of an isolation gown are skin friendliness, cost, comfort, barrier effectiveness, strength, biocompatibility, quality, resistance, etc. The interfaces of the fabrics that are used for the gowns are critical for the protection. The exposed areas of the body that are most vulnerable to infections are forearm, abdomen, chest, cuff, etc. Gowns protecting those areas are often reported as the occurrence of leakage.

Factors responsible for capillary absorption are:

• Characteristics of the fluid such as surface tension, density, viscosity
• Nature of the surface i.e. surface energy and morphology
• Interaction of the fluid with the surface i.e. interfacial tension and contact angle
• Pore characteristics such as size, volume, geometry and orientation

 

Ways of Disease Transmission

Certain types of infectious diseases caused by microorganisms such as bacteria, viruses, pathogens, microbes, fungi, etc., can be transmitted to the patients either by direct or indirect contact.

• Direct Contact
• Person to person contact
• Droplet spread

 

• Indirect Contact
• Airborne transmission
• Contaminated objects
• Food and drinking water
• Vector borne diseases
• Animal to human contact
• Animal reservoirs
• Environmental reservoirs

 

Direct Contact

It is common when infections are transferred directly from microorganisms to person.

Person to Person Contact

Diseases that are infectious are transmitted directly through person to person when in contact with each other. Diseases are transmitted when the affected person touches or through body fluids such as saliva, pus, blood contamination. It also happens without the knowledge of the person who gets infected. Even pregnant women can transmit infections to their fetus and/or during childbirth.

Droplet Spread

This transmission occurs by respiratory droplets that are through coughing, sneezing, talking, etc. The spray of these droplets can increase the chances of transmission from person to person. This exposure can be eliminated or prevented by wearing PPE such as isolation gowns, masks, gloves, etc.  Using the protective equipment, there is a chance of reducing the contact and transfer of microorganisms between doctors and patients.

Thus the effective PPE can provide the adequate protection and safety from these exposures. Based on the closer distance, this type of transmission occurs from person to person.

Indirect Contact

Some of the infectious diseases can be indirectly spread through air and by other means such as:

Airborne Transmission

It occurs by airborne droplet nuclei or by the smaller particles of respiratory droplets consisting of infections. Some of the infections can sustain in the air for a longer period of time which may be transmitted to persons.

Based on the different size of the droplets, respiratory infections are transmitted. When the size of the droplet particles are greater than 5-10 μm in diameter, they are termed as respiratory droplets and when the size is lesser than 5 μm in diameter, it is termed as droplet nuclei. Isolation gowns that are in the usage cannot completely prevent from airborne transmission, however, it reduces the infection to a certain extent depending on the type of fabric used.

Contaminated Objects

Some of the bacteria or microorganisms can live on objects or materials for longer period of time. If the infected person touches or uses any object such as door knob, table and chair in workspace, those objects get contaminated and prone to infection.  Anyone who touches those objects get infected and the infection transmission may occur via mouth, nose, eyes, etc., if hands are not washed properly.

Food and Drinking Water

Food and waterborne diseases are caused by the harmful bacteria, viruses, parasites, algae, fungi, etc. Escherichia coli is transmitted mostly through raw meat or not properly cooked meat. This causes food poisoning in humans due to the presence of bacteria and viruses in it. It also makes the humans sick through the water. Improperly canned foods can develop the environment for Clostridium botulinum.

The U.S. Centers for Disease Control and Prevention define the greatest threats of food- and water-borne illnesses to be from among the following bacteria:

• Salmonella species
• Shigella dysenteries
• Escherichia coli (E. coli)
• Vibrio cholerae
• Cryptosporidium parvum (C. parvum)

Vector Borne Diseases

Vector-borne diseases are caused by viruses that are transmitted by vectors in humans. Some of the vector-borne diseases are as follows

• Malaria
• Schistosomiasis
• Dengue
• Human African Trypanosomiasis
• Leishmaniasis
• Chagas Disease
• Yellow Fever
• Japanese Encephalitis
• Onchocerciasis

Some pathogenic infections are transmitted by insects, such as mosquitoes, flies, etc., when they suck the blood. This disease gets transmitted through insect bites.

Animal to Person Contact

Some of the infectious diseases can be transmitted from animals to humans. The disease gets transmitted when an infectious animal bites or scratches the humans or it is possible even through its waste. For example, Toxoplasma gondii parasite can be found in cat feces. So humans with weaker immune system should take care while handling the animals. They should undertake protective measures like washing their hands often, wearing gloves, etc.

Animal Reservoirs

Diseases from animals can be sometimes transmitted to humans referred to as zoonosis. Zoonotic diseases are

• Anthrax (from sheep)
• Rabies (from rodents and other mammals)
• West Nile virus (from birds)
• Plague (from rodents)

 

Environmental Reservoirs

Infectious agents present in the natural reservoirs such as soil, water and plants can be transferred to human. Hookworm is transmitted from contaminated soil. Legionnaires’ disease is an example of a disease that can be spread by the organism, Legionella pneumophila, that supplies the condensers.

Microorganism can get transmitted through the fabric material of the gown due to the following factors

• Shape and surface characteristics of the microbe
• Characteristics of carriers
• Physical and chemical characteristics of the fabric

Microorganisms have the ability to move through the fabric structure. They are transmitted by body fluids such as blood, saliva, droplets, etc.  It also stated that in the presence of liquids, microbes get transmitted and increases the chances of infection in the human body. Thus the transmission occurs with or without the presence of liquids. Generally, fungi are larger than bacteria (1-5 µm long), and bacteria are larger than viruses.

Microorganisms live on the surfaces for longer period of time, based on the type of its nature, survival period differs from place to place. Some pathogens can survive for several days or months while some may die during cleaning time. Based on the moisture and humidity in the surface, its survival can range from days to weeks or even weeks to months.

Design of the Gown

Generally isolation gowns have three different types of cuffs

• Elastic around the wrist
• Cotton/polyester blend knit cuff
• Thumb loops

According to the research, it is found that the material used on the cuff does not have barrier protection. In order to improve the protection, gloving over the cuff is recommended. This may not provide sufficient protection depending on the procedure performed and the amount of blood involved. The thumb loops helps in keeping the gown wrist in place. The elastic cuff around the wrist is disposable whereas the cotton or cotton/polyester blend knit cuffs are both disposable and reusable. Another proposal of redesign is a gown with a dart at the terminal forearm, sealed by liquid-proof method and sealing sleeve to the proximal end of the glove.

In general, there are three types of neck closures used for isolation gowns, i.e., tie, tape tab, hook and loop neck closures. Gowns with hook and loop neck type closures are designed for easy adjustability.  The tape tab type is designed for ease making it comfortable to don and doff. Gowns with hook and loop neck allows the neckline to be adjusted according to size.

Professionals in emergency room, EMS workers often find it difficult to wear isolation gowns. It should be designed in such a way that it is easier to don and doff and the wearer feels comfortable in it.

The isolation gowns come in different sizes or fit (small, medium, large, etc.) as well as in universal sizes which mostly does not fit the workers adequately. Isolation gowns should be easy to wear and remove without cross-contamination at workplace or the workers, should fit the wearers of different sizes and body shapes, and should provide comfort while working. Gowns that are not properly fitted may increase the risk of exposures to bodily fluids and infection. According to the Centers for Disease Control and Prevention, gowns should be available in different sizes in healthcare facilities to ensure proper protection for their staff.

The design of isolation gowns and other protective equipment's are influenced by factors:

• Comfort
• Cost
• Regulation
• Degree of protection

There are no standard specifications for isolation gowns regarding performance and design criteria  During the design and development of personal protective equipment, designers afford to achieve maximum protection with highest level of comfort at the lowest cost. Comfort is one of the major characteristics for the gowns in healthcare, so it is essential to design the PPE that should be protective as well as comfortable for the workers. The design of the isolation gown faces many design problems such as the seams, hems, cuffs, bindings and should satisfy the barrier performance up to the designated level.

Some of the isolation gowns available in the market have open-back pattern for comfort, but these are not rated to the standards for protection. Some gowns are designed inappropriately where the fabrics overlap in the back of the body.  If it does not fit the wearer appropriately, it can lead to opening at the back of the garment, thus exposing to bodily fluids and infections.  Some isolation gowns have ties which are tied around the body.  If the ties are not secured properly, it may lead to hazard.

 

Isolation gown designed should provide breathability (thermal comfort), should be comfortable to wear for a longer period, should not have restrictions to body movement and should be eco-friendly.

 

Conclusion

Isolation gowns are one of the protective equipment's used for the protection of people in the hospital environments. Gowns are widely used and thus rated second most widely used material in the market among the PPE after the wide usage of gloves. The design of the isolation gown, its size, fitness and fabric properties makes the design much more effective. The performance of the gown varies according to the cost, comfort and the protection it provides to the wearer. Isolation gown should be chosen according to the nature of treatment given to the patients and based on how closer the contact exists between the doctors and patients, the degree of exposures to infectious material and bodily fluids, duration of the procedure or treatment, and other tests taken during the procedures.

Since the end users are not fully aware on the performance of the isolation gowns, proper guidance documents regarding design requirements and minimum performance of the gowns should be provided. This can aid healthcare professionals to select appropriate gowns for use. Design and performance characteristics vary based on the cost, comfort and the amount of barrier protection provided.  Therefore, it is essential for a manufacturer to design the gowns that are both protective and comfortable.