Surgical Asepsis

by | Apr 24, 2024 | Nurse Article | 0 comments

Surgical Asepsis

Surgical asepsis refers to all the procedures used to keep objects or areas sterile or completely free from all microorganisms.

In medical asepsis, all practices are directed to the prevention of pathogenic organisms entering into the body, but in surgical asepsis all practices are directed to the elimination of both pathogenic and non-pathogenic microorganisms. In medical asepsis, a “clean technique” is used, but in surgical asepsis a “sterile technique” is used.

Principles of Surgical Asepsis


1. Always face the sterile field. Do not turn your back or side on a sterile field.

Reason: sterile objects which are out of vision are considered questionable and their sterility cannot be guaranteed.

2. Keep sterile equipments above your waist level or above table level.

Reason: waist level and table level are considered margins of safety and will promote maximum visibility of the sterile field.

3. Do not speak, cough or sneeze over a sterile field. If it is necessary to do so, turn your head away from the sterile field.

Reason: to prevent droplet infection.

4. Never reach across a sterile field.

Reason: when a non-sterile object is held above a sterile object, gravity causes the microorganisms to fall into the sterile field.

5. Prevent excessive air currents around the sterile areas. Air currents can be caused by moving fast, flapping the clothes and drapes and by closing the doors etc.

Reason: microorganisms are present in the air and they travel in currents.

6. Keep the unsterile objects away from the sterile field.

Reason: microorganisms may be transferred whenever a non sterile object touches a sterile field, thus rendering the sterile objects contaminated.

7. Handle liquids cautiously near the sterile field or prevent drapes or wrappers from becoming wet.

Reason: when a liquid connects a non sterile field with a sterile field, the microorganisms may be transferred. Consequently, the sterile area becomes unsterile by capillary action.

8. Keep the sterile field dry.

Reason: microorganisms do not pass easily through a dry surface.

9. The edge of the sterile field is considered unsterile.

Reason: proximity to a contaminated area makes sterility doubtful.

10. Each sterile supply should be clearly labeled as to its contents, time and date of sterilization.

Reason: to ensure sterility.

11. Never assume that an object is sterile. Always check the sterility expiration date.

Reason: sterility of an object wrapped in paper or cloth becomes doubtful after 4 weeks and those sealed in polythene bags becomes doubtful after 1 year.

12. Avoid sweeping and dusting when the sterile objects are opened.

Reason: microorganisms travel in the dust particles.

13. Wash hands, put on gowns, gloves and masks before handling the sterile supplies.

Reason: to prevent contamination.

14. Open the sterile packages in such a way that the edges of the wrapper are directed away from the worker.

Reason: to avoid the possibility of a sterile surface touching the uniform.


1. Hold the transfer forceps pointing downwards.

Reason: to prevent the solution from flowing onto the contaminated area (the handle of the forceps) and then back to the sterile area (the tip of the forceps)

2. When removing the forceps from the container, lift off without touching the sides and the rim of the container.

Reason: the tip of the forceps will become contaminated when touching the container that is not in direct contact with the disinfectant solution.

3. Keep the prongs (tip) of the forceps within the vision while using them.

Reason: sterile objects that are out of vision may touch the unsterile objects accidently.

4. Gentle tap the prongs together directly over the container to remove the excess solution.

Reason: to prevent the solution dribbling on to the sterile field and wet it.

5. Transfer forceps and the container should be sterilized daily.

Reason: there is a great possibility of these articles becoming contaminated because of their frequent and varied use.


1. Remove the cover from the container when necessary and only for a short period of time.

Reason: the air currents can contaminate the cover.

2. Lift the cover of the container in such a way that the inside of the lid is pointing down.

Reason: the air currents can contaminate the inside of the cover.

3. Invert the cover only when it is necessary to place it down.

Reason: contact with the unsterile surface contaminates sterile objects.

4. Consider the rim of the cover and the container to be contaminated.

Reason: proximity to a contaminated area makes sterility doubtful.

5. Do not return the unused sterile objects to the container, once they have been taken out.

Reason: it is considered to be contaminated by the air currents.



Hand Washing

In surgical asepsis, the hands should be thoroughly cleansed for about 3 to 5 min. (In operating room, hands are scrubbed up to 10 min). when washing hands, they are held above the level of the elbows (in surgical asepsis, the elbows are considered more contaminated than the hands). So the water should run from least contaminated area (hands) to the area of greatest contamination (elbows). It is important to put soap well and scrub with a brush and rinse thoroughly with water several times. A sterile towel is used to wipe the hands and arms, starting from the palms to the elbows. Prior to surgical scrubs, it will be necessary to put on the head caps and masks.


Opening a Sterile Wrapped Package

1. Wash hands thoroughly.

2. Choose a large, clean working area above waist level.

3. Place the package in such a way that it can be opened away from the body.

4. The flap farthest away is opened first, with care not to reach over the sterile field.  Then the side flaps are opened, and the flap nearest to the nurse is opened last.


When opening the flaps, care must be taken not to touch the inside of the wrapper. When opening the last flap, it is important to stand well back from the package in order to avoid contamination from the nurse’s uniform. In an inner wrapper is present, it is opened in the same way, but using a sterile forceps.

When trays need to be wrapped (e.g. after solutions have been added to a dressing tray before it is taken to the bedside) it should be wrapped in the reverse order to that of unwrapping. The proximal flap is closed first to prevent reaching across the sterile field, the side flaps next, and the distal flap last.

Use of Gloves

To put on the first glove, the nurse grasps the glove by its cuff, being careful to touch only the inside of the glove. The sterility of the outside of the glove must be maintained. Remember that the nurse’s hands are considered to be contaminated.  To put on the second glove, the sterile gloved hand must be used. The second glove is picked up by inserting the gloved finger under its cuff. The second glove is then pulled. The cuff of both gloves may then be unfolded by touching only the sterile sides.


Sterile gowns are worn in the operating room and the delivery room an whenever open wounds are present which necessitate a sterile technique e.g., to attend to a client with burns. To keep the gowns sterile, they are folded inside out and are touched only on the inside.

The points to remember when wearing a gown:

1. Put on the head cap and mask first.

2. Scrub hands thoroughly.

3. Dry the hands with sterile towel.

4. Pick up the gown by grasping the folded gown at the neck. Stand well back about one foot from the sterile bundle and the table.

5. Unfold it by keeping the gown away from the body. Do not shake the gown.

6. Hold the gown at the shoulder seams (inside) and put each hand alternately into the arm holes.

7. Extend the arms and hold hands upward at the shoulder height when putting them through the arm hole.

8. The circulating nurse the assist her in pulling the sleeves by working from behind and holding the gown from the inside.

9. The gown is then fastened at the neck by the circulating nurse and the open edges are then folded or held together.

10. The waist ties are then fastened by the circulating nurse from behind.



Medical asepsis refers to all practices used to protect the clients and his environment from the transmission of disease producing organisms (prevention of cross infection).


Cleaning of Articles

An article is considered to be clean when it is free from pathogenic organisms. The following steps should be considered while cleaning the articles:

1. Rinse the articles first with cold water to remove the organic material. Hot water coagulates the organic matter and tends to make it stick to the article.

2. Then wash the articles in hot water and soap. Soap has an emulsifying action as it reduces surface tension which facilitates the removal of dirt. Rinsing with water assists in washing the dirt away.

3. Use an abrasive such as a stiff bristled brush and a paste or powder to wash the articles. Brush will help to remove the dirt from the grooves and corners.

4. Rinse the article with clean water.

5. Dry them with a towel. There is less chance for the bacteria and dirt to lodge on the cleaned articles when it is dry.

6. Disinfect or sterilize if indicated.


Hand Washing

The infection can be transferred from person to person through contaminated hands. Careful washing of the hands reduces the number of bacteria. Hand washing involves both mechanical and chemical action. The running water and friction used in cleaning are the mechanical action of cleaning. The soap will emulsify the fat and lower the surface tension of water, facilitates the removal of microorganisms, dirt and oils.

The points to be kept in mind while washing hands are:

1. Cut short nails. A long nail will give roof to the dirt and microorganisms.

2. Remove the jewellery of any type. Open the tap and wet hands and forearm. Always hold the hands below the elbow level, because hands are considered to be more contaminated than the elbows, hence the water should flow from the area of least contamination (the elbows) to the area of more contamination (the hands).

3. Apply soap or detergent. Rinse the soap before it is returned to the container.

4. Wash hands thoroughly. Make sure that the inter digital spaces are well cleaned by washing each finger separately. Use brush to dislodge the dirt from under the nail beds.

5. Rinse hands by keeping the hands well below the elbow level. The water flows from the elbow to the hands.

6. Repeat the procedure (application of soap and rinsing with water) to ensure thorough cleanliness.

7. Dry the arms and hands, starting at the elbows and working towards the hands. Discard the towel.

8. Turn off the water tap using a paper towel because the handle is contaminated.


While washing, if the hands touch the sink or other objects accidently, the whole procedure needs to be repeated. Disinfection of hands with a mild antiseptic lotion is unnecessary.


Gown Technique

The isolation gown should be made with long sleeves, long skirt and high neck to cover the clothing of the wearer. The isolation gowns should be used only once and then discarded. The older practice of re-using gowns is no longer recommended.

The points to be remembered while using a gown (before use):

1. Remove watch and rings because jewellery can harbor microorganisms.

2. Wash hands and dry.

3. Hold the gown at the neck on the inside permitting to unfold (the open part of the gown is turned towards the nurse).

4. Slide hands and arms down the sleeves.

5. Fasten the ties at the neck.

6. Overlap the gown at the back as much as possible. Secure the waist band.


The points to be remembered while removing the gown (after use):

1. Untie the waist band.

2. Wash hands.

3. Untie the neck ties (be sure not to touch the outside of the gown).

4. Slide the gown down the arms and over the hands by holding the inside of the sleeves.

5. Hold the gown with both the hands (inside the shoulders) at the shoulder seams. The gown is turned inside out. The hands are then brought together, and the gown is rolled  and discarded in the container provided.

6. Wash hands thoroughly.


General Instructions

 1. Gown is worn only in the client’s unit and never outside.

2. The gown is worn by a nurse when caring for a client whose infection is known to be spread by indirect contact, or when it is necessary to protect nurse’s uniform form contamination by the client’s pathogens.

3. The gown is worn by the infected person when he is transported outside his room. The gown prevents the client’s contaminated clothing from touching clean areas.

4. The gowns are worn by the nurses when caring for the persons whose resistance to infection is diminished e.g., premature babies. The gown prevents the client from contact with any organism that could be on the uniform of the nurses.

5. The outside of the gown is considered to be highly contaminated and the inside of the gown is considered to be clean.

6. If the gown is to be re-used, hang the gown inside the client’s unit with the contaminated side folded out. Hang the gown outside the client’s unit with the contaminated side folded in.

Face Masks

Masks are generally used to prevent the spread of microorganisms to and from the client, through the respiratory tract. Masks should be worn only once and then discarded to ensure effective filtering of microorganisms. Masks that become wet are less effective and should be discarded. It is desired that the masks should be worn not more than 1 to 2 hours at a time. The mask is not worn outside the unit. Masks need to cover both mouth and nose, and fit snugly around the face to prevent the escape of microorganisms around the sides. There should be minimum layers of cloth for the effective filtration of air.

The points to be remembered while wearing the mask:

1. Wash hands.

2. Remove the clean mask from the container with sterile forceps (the mask should be sterilized and kept for the use).

3. Hold the mask by its strings. Fit it to the face and tie the strings at the back of the head. Do not touch the mask that covers the face, it is important that both mouth and nose must be covered.

To remove the mask:

1. Wash hands.

2. Remove the gown (if worn)

3. Remove the mask and discard it in the container for “used masks”.

4. Wash hands thoroughly.



Gloves are used in the medical asepsis to protect the nurse from pathogens. They serve as a barrier when the nurse handles articles contaminated by the faeces or wound discharges. Gloves may be worn by the nurses to protect the clients with poor resistance.

Gloves used for this purpose are clean but need not be sterile. Gloves are changed after each contact with the bodily discharges, to avoid cross infection of the clients with their own organisms. For example, gloves used for the  cleaning of the client should be changed before feeding the client. Gloves must be changed between the two activities.

The points to remember while wearing the gloves:

1. Wash hands.

2. Dry the hands and apply powder to facilitate insertion of gloves.

3. Put on the “clean” gloves.

After attending to the client, remove the gloves and discard them in a container with antiseptic lotion. Wash hands thoroughly.


Concurrent Disinfection

Concurrent disinfection means the immediate disinfection of all contaminated articles and bodily discharges during the course of the disease. It includes:

1. Cleaning of the isolation unit daily, including the floors using an effective disinfectant.

2. Disinfection of all articles including the soiled linen, contaminated articles etc, before it is sent out of the unit.

3. Disposal of all wastes by incineration.

4. Safe disposal of excreta.


The stool and urine in enteric isolation should be mixed with equal quantity of freshly prepared lime (1 part of lime to 4 parts of water) and allowed to stand for 2 to 4 hours. Then it is disposed by burial. The stools can be burned after mixing it with saw dust.

In hospital practice, however, the septic tanks are in use and they are best means of the disposal of excreta.  No stool with any disinfectant should be discarded in a septic tank because the disinfectant will hinder the natural biologic action.

The sputum can be collected in a sputum cup with a lid. The container needs to contain either water or disinfectant lotion so that the sputum will not stick to the sides. When the container is full, it needs to be boiled ro burned.


Terminal Disinfection

The terminal disinfection is the disinfection of the client’s unit with all the articles used on discharge, transfer or death of a client who had been suffering from a infectious disease.

Fumigation is often used for this purpose. The commonly used agents are sulphur and formalin. The doors and windows including all crevices are closed prior to fumigation.


Fumigation with Sulphur

The room should be filled with stream by boiling a kettle of water in the room as the sulphur fumes act better on a damp surface. A small room of 100 c. feet would require about 220 grams sulphur which is placed in an earthen ware which stands in a larger one containing water. A little methylated spirit is poured over the sulphur to ensure burning the sulphur completely. Lit fire to the sulphur and close the door. The room is opened after 24 hours.

The effectiveness of this method depends upon several factors such as gas concentration, temperature of the room, exposure time and humidity. All articles should be kept open for the thorough penetration by the fumes.


Fumigation with Formalin

Formalin is more efficacious as a surface disinfectant and is also more expensive. For every 100 c. feet of room space that is to be disinfected, take 140 grams of potassium permanganate crystal and 250 ml of formalin, mix it and place them in a metal bowl. The heat produced by the chemical action evaporates the formaldehyde. The room should be sealed for 12 to 24 hours.

At the expiration of the stated time, the doors and windows are thrown opened.

Management of the Isolation Unit

A unit that is set up for the isolation of clients needs to have the following equipment:

1. Hand washing facilities – skin, water tap, soap, brush etc.

2. Paper napkins.

3. One table to place necessary supplies for the care of the client, e.g., thermometer, dressing trays etc.

4. Toilet facilities for the client – water closet, bathing facilities etc.

5. Garbage receptacle with paper lining.

6. An area outside the client’s room for keeping clean supplies for the nurse e.g., gloves, gowns, masks etc.

7. Vessels for disinfection of articles with disinfectant solution.

8. Door cards stating “ISOLATION” to hang on the door.


The nurse before entering the rooms washes her hands, put on clean gowns and mask and enters the room. She then closes the door and attends to the client. She wears gloves if necessary. She makes use of all medical aseptic practices to prevent the spread of infection.

After attending to the client’s needs she leaves the room, closes the door, removes the gown and mask and discards them in the containers with the disinfectant lotion. She then washes her hands thoroughly.