Aseptic technique in theatre

Asepsis is the absence of pathogenic microorganisms that cause disease. It can also be referred to as clean technique (Phillips, 2013).

Surgical aseptic technique is a method employed to maintain asepsis and minimise the risk of introducing pathogens into a surgical wound (Rowley et al, 2010). It protects the patient from the impact of healthcare associated infections such as delayed recovery, longer hospitalisation, increased pain and increased morbidity (Phillips 2013). It should never be compromised for the sake of convenience of the caregiver. An emergency situation in which asepsis becomes a secondary concern is a rare occurrence. (Phillips 2013).

Sterile technique is a method by which contamination by micro-organisms is prevented to maintain sterility throughout the surgical procedure (Phillips 2013). It is achieved in theatres by using sterilised instruments placed within a sterile field. A sterile field is created by ensuring that the patient, operating table, and instrument trolleys are covered in sterile drapes. All equipment and instruments are sterile and are placed within the sterile field, and all staff operating within the sterile surgical field have performed a surgical scrub and are wearing sterile gowns and gloves (Phillips, 2013). Staff must be aware of the differences between sterile and non-sterile items and share the responsibility for monitoring aseptic practice (Association for Perioperative Practice (AfPP), 2016) (Rationale 2).
Sterilisation is defined as a process which removes or destroys all micro-organisms including spores (Phillips, 2013). This is achieved by using sterile single-use items or instruments that have been processed by the Hospital Sterilisation and Disinfection Unit (HSDU). 


The following checks must be performed prior to the opening of any sterile glove, gown, or instrument set:
The surfaces upon which the sterile packs will be opened should be clean and dry (Rationale 1, 29) (Phillips, 2013).
All items introduced to the sterile field should be opened, dispensed, and transferred by methods that maintain both their sterility and integrity (Rationale 1) (AORN, 2010).
Non-scrubbed individuals must not at any time lean over the sterile trolley or any sterile surface. (Rationale 1, 22) (AORN, 2010).
All items should be delivered to the sterile field in a manner that prevents non-sterile objects or personnel from extending over the sterile field. If care is not taken, it is possible to touch the inside of a package while opening it. It is also possible for the outside of the package to touch the inside, sterile portion (Rationale 1, 21) (AORN, 2010).

Gown and gloving

A surgical scrub is performed as per the Hand Hygiene guidelines prior to donning a sterile gown and gloves (Rationale 3) (Phillips, 2013). Splashing water on scrub attire or the gowning table must be avoided (Rationale 25) (Phillips, 2013)
Sterile gowns must be CE approved and tested for the following (Rationale 1, Rationale 2):
  • Resistance to microbial penetration(dry and wet)
  • Cleanliness (from microbial particulate matter)
  • No lint production
  • Resistance to liquid penetration
  • Bursting strength (dry and wet)
  • Tensile strength (dry and wet) 
A sterile surgical gown and gloves are worn to exclude skin as a possible contaminant and create a barrier between sterile and nonsterile areas (Rationale 4). They should be donned from a surface other than the working sterile field (Rationale 5) and checked for integrity immediately following donning (Rationale 6). 
A closed gloving method is recommended for the initial donning of gloves (Rationale 7) (Phillips, 2013). The hands should be kept inside the cuffs until the glove is applied. The closed gloving process is as follows: 
  1. Using the cuff covered hands, place the glove wrapper in front of you like a book. First open the two sides then open the inner fold of the glove wrapper by grasping the two lower corners. 
  2. Extend the right forearm. With the cuff covered left hand, pick up the right glove from the glove wrapper by grasping the fingers and lifting straight up and placing the glove on the right palm (which is in the cuff of the gown) thumb side down and the fingers are pointing towards the shoulder. 
  3. Grasp the edges of the cuff with the cuffed left hand and the opposite edge with the cuffed right hand. Peel the glove over the right cuffed hand, the end of the sleeve and wiggle the fingers to extend them into the glove covered right hand. The cuff of the right glove is now covering the cuff of the right sleeve. 
  4. Grasp the cuff of the right glove and underlying right gown sleeve with the covered left hand and extended fingers pulling the glove and cuff over the hand. The glove cuff must remain over the cuff of the gown.
  5. Repeat the sequence for applying the left glove (Phillips, 2013).
After the gown cuff has risen to the wrist, it should never be pulled down over the hand again, any subsequent glove changes should be done using open glove technique or assisted gloving (Kennedy, 2013) (Rationale 23 24).
The open glove technique is described as follows:
  1. With the left hand grasp the inner edge of the cuff of the right glove and lift from the wrapper while taking care not to touch the inner edge of the wrapper. 
  2. Align the fingers of the right hand and insert the right hand into the glove, pulling it on while leaving the cuff turned down over the hand. Be sure to keep the thumb adducted into the palm of the hand until it is well inside the confines of the glove. Do Not adjust the cuff at this point. 
  3. Slip the fingers of the sterile right hand into the everted left cuff on the sterile side of the glove. 
  4. Align the fingers of the left hand and insert the fingers into the left glove, keeping the thumb adducted until well inside the glove. Pull the left glove on all the way unfolding the cuff of the glove over the cuff of the gown at the wrist. 
  5. At this time pull the cuff of the right glove over the cuff on the sleeve over the right wrist (Phillips, 2013)

Gloves act as a barrier to the prevention of transmission of infection between staff and patients (Rationale 1)(AfPP, 2016).

The choice of surgical glove and double gloving depends upon the risk of glove perforation from the surgical procedure being performed. Double gloving provides an extra layer of protection and significantly reduces the number of perforations to inner gloves. When double gloving, the first glove put on should be a half size bigger to create a cushion of air and minimize the incidence of medial nerve compression. 
Alternative gloves must be available for individuals and patients who are sensitive to natural latex proteins and/or other chemicals in gloves. 
Only the following should be considered sterile on the surgical gown and gloves:
  • Fingertip to above the elbow (Rationale 8).
  • Below the nipple to waist level. Hands must be kept at or above waist level and below shoulder level and should be visible at all times in order to avoid inadvertent contamination (Rationale 8).

Glove contamination.

When a glove becomes contaminated it needs to be changed, if the contamination is deemed to be superficial, a second glove can be placed over the first one using the open glove technique. If the nature of the contamination is a puncture, the contaminated glove and any object involved with the contamination should be held away from the sterile field for removal. The circulating practitioner, wearing protective gloves and eyewear, should remove the contaminated object/s. The circulating practitioner should then remove the contaminated glove from the scrub practitioner by grasping the cuff 5cm below the top of the glove and then pulling off the glove inside out taking care not to snap the glove creating an aerosol. It is preferable that a scrubbed person gloves the person without contamination of the inside of the glove. If this is not possible an open glove technique should be used (Rationale 1) (Phillips, 2013).

During the procedure

The following precautions must be taken by the scrub practitioner:
  • The sterile field should be constantly observed and not left unattended at any time after is has been set up (Rationale 1).
  • Conversation should be kept to a minimum in the surgical area and masks should be worn (Rationale 9).
  • The number of individuals in the theatre and around the surgical field should be limited to essential personnel and to facilitate a minimum number of observers who are training (Rationale 9).
  • Movement around the sterile field, including the opening and closing of doors should be kept to a minimum (Rationale 9, 22, 27, 28).
  • Non-perforating devices should be used to secure equipment to the sterile field (Rationale 10).
  • Non-sterile equipment should be covered with sterile barriers before placing them in or over the sterile field (Rationale 1).
  • Staff scrubbed should stay within the sterile field during the intraoperative procedure and not walk around or go outside the operating theatre in their sterile gown and gloves (Rationale 11, 31).
  • When changing positions scrub staff should pass back-to-back or face-to-face (Rationale 11).
  • Scrubbed staff should avoid changing levels, such as sitting and standing (Rationale 11).
  • A wide space should be observed between scrubbed staff and non-scrubbed staff. When moving about the theatre circulating practitioner should maintain a distance of 30cm from any area of the sterile field. (Rationale 9, 22) (Phillips, 2013).
The following precautions must be taken by circulating staff:
  • Circulating practitioner should face the sterile field on approach (Rationale 1).
  • Circulating practitioner should not touch or lean over the sterile field (Rationale 1, 22).
  • Circulating practitioner should not walk between two components of the sterile field (Rationale 1, 22) (Phillips, 2013).
  • Hand hygiene practices should be followed prior to passing sterile items to the scrubbed person. 
If extra items are required to be added to the sterile field the packaging must be inspected to ensure that:
  • It is the required item.
  • The package integrity has been maintained.
  • The sterilisation indicator is present.
  • It has not exceeded its expiry date.
  • The packaging is not wet (Rationale 2, 15).
It is possible to have questionable wet spots in the packaging material. If there is any possibility that moisture is present, the items should be considered unsterile, should not be used, and should be returned for reprocessing (Hopper & Moss, 2010).
All items introduced to the sterile field should be opened, dispensed, and transferred by methods that maintain both their sterility and integrity (Rationale 1, 2, 14,15) (AORN, 2010). To maintain asepsis it is essential that all staff members are aware of the correct method of opening different sterile packages. The following practices should be undertaken:
For instrument trays wrapped in a paper wrap:
  • Place the wrapped instrument tray on a clean, dry table surface
  • Check the external chemical indicator to be certain that the item has been exposed to the sterilisation process, 
  • Break the tape at the juncture between folds (Rationale 30), open the wrapper flap by lifting the side flaps off to the side so that both sides are off the end of the table
  • To open the central flaps begin by opening the flap furthest away first to prevent contamination from passing an unsterile arm over the sterile items. The nearest flap should always be opened last. It is easiest opening the wrap with two people one standing on each side of the table. 
For instruments or supplies wrapped in a peel pouch:
  • Contents should be presented to the scrubbed person to prevent contamination of the contents by:
  • The circulating practitioner gently peels open the package to allow the scrub practitioner to take the inner package by grasping it or using a forceps. 
Rigid containers:
  • Open on a separate surface, by breaking the seal on the side of the lid, raising the lid up away from the tray. 
  • The inner basket is sterile. 
  • Supplies should never be opened into the container and basket because the top edge of the container is not considered sterile
If there is any doubt about the sterility of an item, it should be considered unsterile and therefore not used. 
Sterile items should be given directly to the scrub practitioner or placed securely on a specific area of the sterile field. Care should be taken not to cause items to roll off or become displaced. Enclose your hand in the wrapper as much as possible to avoid reaching over the sterile field. 
When sharps are offered they should be opened onto a designated container (Rationale 10, 12)
Sterile items should be lifted straight up from their packaging, not dragged over the packaging edges (Rationale 13) (Phillips, 2013). A sterile forceps may be used by the scrub practitioner to take individual sterile items from their packaging (Rationale 14) (Phillips, 2013).
Heavy sterile items should be placed on a separate surface to be opened (Rationale 15).
In order to add a solution to the sterile field, first the circulator should perform hand hygiene, and then should confirm the contents of the solution and the expiry date with the scrub nurse (Rationale 1, 2). The scrub practitioner should label a bowl with the name of the solution; and then hold the sterile labelled bowl away from the sterile field or place it near the edge of the sterile field while the solution is being poured into it (Rationale 16) (Phillips 2013). Solutions should be poured slowly to avoid splashing. Once saline or water are opened the bottle should not put back into the solution warmer (Rationale 16, 17) (AfPP, 2016).

Moving sterile trolleys

Only the top surface of a draped trolley is considered sterile (Phillips, 2013). The circulating practitioner must always move draped trolleys by grasping them well below the sterile drape. The scrub person should not move trolleys by grabbing around the top and underside of the trolley top with gloved hands. If the scrub practitioner needs to move the trolley, he or she should push on the top of the trolley with gloved hands (Rationale 1) (Hopper & Moss 2010)
Trolleys should not be moved from one operating theatre to another. The sterile field should be prepared in the location in which it will be used. (Rationale 27, 28)

Leaving sterile items opened

Ideally sterile tables are set up just prior to the surgical procedure. (Rationale 26)
In the event of an unanticipated delay after a sterile field is prepared, this can be covered though it should not be an everyday practice. The recommended method for covering uses two trolley covers and an overlapping technique. With this technique, two cuffed drapes are placed horizontally over the sterile surface at or slightly beyond the midpoint.
The second drape should completely cover the cuff of the first drape. To remove the drapes, the second drape should be removed first by the circulating practitioner pulling it up and away from the sterile field toward himself/herself. The first drape should be then removed from the opposite side of the field in a similar fashion. This technique permits the drapes to be removed without the section that has descended below the sterile field being brought above the sterile field, which could contaminate the field. Even if the sterile field is covered it still requires monitoring (Rationale 31) (Phillips,2013).

Dealing with contamination

Any contamination of the sterile field must be acted upon immediately, and if the sterility of a drape or a piece of equipment is in question, consider it to be contaminated (Kennedy, 2013).
Any contaminated equipment must be removed from the sterile field (Rationale 19). If the sterile drapes become contaminated then re-draping must be performed (Rationale 20). Sterile gloves should be changed if a glove perforation occurs (Rationale 19) (Phillips, 2013). If a sharp or needle stick injury occurs to a person scrubbed at the sterile field please refer to the Clinical guideline: Sharps injury: exposure to blood borne viruses.


Labels from sterile instrument sets or from single items processed within HSDU should be entered onto the Trust's Tracking System. The labels can then be put on the sets or supplementary instrument when they are returned to HSDU (Rationale 21).


Rationale 1: To prevent contamination of the sterile field.
Rationale 2: To ensure sterility of the item. 
Rationale 3: To reduce the number of micro-organisms present on the staff member's skin.
Rationale 4: The gown protects the wearer and the patient from cross-contamination (Phillips 2013).
Rationale 5: To prevents water being dripped onto the working sterile field (Rothrock 2015).
Rationale 6: To identify any holes.
Rationale 7: The gloves are handled through the fabric of the gown sleeves. This ensures that no skin is exposed and provides the most assurance against contamination (Kennedy, 2013).
Rationale 8: The scrub practitioner cannot constantly observe the back of the gown, so it is deemed unsterile. Perspiration may gather under the arms, and the collar touches the skin of the scrub practitioner. The gown is considered unsterile below the level of the sterile trolley (Rothrock, 2015).
Rationale 9: To prevent airborne contamination. Microorganisms in droplets are forcibly expelled through talking, coughing or sneezing. 
Rationale 10: To prevent creating holes in the sterile drapes.
Rationale 11: To avoid contaminating the sterile gown.
Rationale 12: To prevent a sharps injury.
Rationale 13: The edges of sterile enclosures are considered unsterile.
Rationale 14: A sterile forceps may be used as an extension of the scrub practitioner's hand to ensure a margin of safety between fields (Phillips, 2013).
Rationale 15: To prevent contamination of the object.
Rationale 16: To prevent spillage causing strikethrough contamination.
Rationale 17:To prevent the label and expiry date being obscured in the event of spillage.
Rationale 18: Reuse of opened containers may contaminate the solutions.
Rationale 19: To prevent further contamination of the sterile field.
Rationale 20: To create a new sterile field.
Rationale 21: The records kept for the decontamination process should be able to prove retrospectively that the instrument has passed through each stage of the sterilisation process. Records need to be kept for traceability purposes (Phillips, 2013 ).
Rationale 22: To prevent personal shedding over the sterile field. The average individual sheds an estimated 4000 to 10,000 viable contaminated particles from the skin per minute. The major areas of microbial shedding include the head, neck, axillae, hands, groin, perineum, legs and feet (Phillips, 2013).
Rationale 23: Using sterile technique helps prevent contamination of the surgical environment and can help reduce the incidence of SSI (Kennedy, 2013).
Rationale 24: Drawing the cuff over the hand may result in contamination of the cuff (Kennedy, 2013)
Rationale 25: Moisture from the freshly scrubbed arms and hands which has dripped on the gowning table can contaminate the surgical gown and gloves (Phillips, 2013).
Rationale 26: Opening sterile items and setting up a sterile as close to the time of surgery decreases exposure to possible contamination within the environment (Phillips, 2013).
Rationale 27: Rapid movement of draping materials creates air currents on which dust, lint, and other particles can migrate (AORN, 2010).
Rationale 28: Moving tables stirs air currents that can contaminate the sterile field (AORN, 2010).
Rationale 29: Accidental wetting of a package contaminates the contents. Packaging must always be handled with dry clean hands and placed on a dry surface (Phillips, 2013).
Rationale 30: Removing the tape increases the risk of tearing the paper wrap (Phillips, 2013).
Rationale 31: Sterility cannot be assured without direct observation of the sterile field (Phillips, 2013)


Association of periOperative Registered Nurses (AORN). (2010) Recommended practices for maintaining a sterile field. Perioperative Standards and Recommended Practices. AORN Inc. Denver CO 2010: 91-99. 

The Association for Perioperative Practice (AfPP). (2016) Standards and recommendations for safe perioperative practice. Harrogate. The Association for Perioperative Practice, 171-228. 

Hopper, WR, Moss, R (2010) Common breaks in sterile technique: clinical perspectives and perioperative implications. AORN Journal 91(3): 350-367. 

Kennedy, L (2013) Implementing AORN recommended practices for sterile technique. AORN Journal 98(1): 15-23.

Phillips, N (2013) Berry and Kohn’s Operating Room Technique 13th Edition. St Louis, MO., Elsevier, 252-266.

Rothrock J. (2015) Alexander's care of the patient in surgery (15th ed.). St Louis, Mosby.

Rowley S, Clare S, Macqueen S, Molyneux R (2010) ANTT V2: An updated practice framework for aseptic technique. British Journal of Nursing 19(5): S5-S11.

Document control information

Lead Author(s)

Kathryn Fawkes, Team Leader, VCB Theatres

Additional Author(s)

Margarida Rodriques, SSN

Document owner(s)

Kathryn Fawkes, Team Leader, VCB Theatres

Approved by

Guideline Approval Group

Reviewing and Versioning

First introduced: 
01 May 2003
Date approved: 
25 September 2014
Review schedule: 
Three years
Next review: 
25 September 2020
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