Asepsis and Aseptic Practices in the Operating Room

Asepsis and Aseptic Practices in the Operating Room

by Cathy Osman, RN, BSN, CNOR

Preventing surgical site infection in the operating room is the primary goal of the surgical team, and all activities performed by the team support this goal. Some of these activities include patient risk assessment, environmental cleaning, disinfection and sterilization of instrumentation, patient antibiotic prophylaxis, and the use of standard precautions. However, operating room activities pertaining to asepsis and aseptic practices have the greatest direct impact upon the surgical team in helping to reduce the patient's risk to surgical site infection.

The goal of asepsis is to prevent the contamination of the open surgical wound by isolating the operative site from the surrounding nonsterile environment.1 The surgical team accomplishes this by creating and maintaining the sterile field and by following aseptic principles aimed at preventing microorganisms from contaminating the surgical wound.3

The standards and recommended practices, developed by the Association of periOperative Registered Nurses (AORN), are guidelines to be used by the surgical team to achieve the optimal level of technical and aseptic practice when caring for their patients in the perioperative setting.3 These guidelines are not to be considered policies. They should be used by institutions to provide direction and information on perioperative practice as they incorporate them into their own policies and procedures.

The principles of aseptic technique play a vital role in accomplishing the goal of asepsis in the operating room environment. It is the responsibility of each surgical staff member to understand the meaning of these principles and to incorporate them into their everyday practice. The principles of aseptic technique include the following principles.

Principle #1

Scrubbed persons function within a sterile field.2

The surgical team is made up of sterile and nonsterile members. Sterile members or "scrubbed" personnel work directly in the surgical field while the nonsterile members work in the periphery of the sterile surgical field. All surgical team members wear scrub attire. In addition to scrub attire, scrubbed persons must wear a sterile surgical gown, mask, and gloves within the sterile field to establish bacterial barriers.2,4 These barriers protect the patient from the transmission of microorganisms from the surgical team.

Once the scrubbed person dons the sterile surgical gown, the gown's sterility is limited to the gown portions directly viewed by the scrubbed person. These sterile areas include the gown front, from chest to the sterile field level, and the sleeves from two inches above the elbow to the cuff.2,4 The scrubbed personnel always perform a surgical hand scrub prior to donning their sterile surgical gown and gloves.

Principle #2

Sterile drapes are used to create a sterile field.2,5

Sterile surgical drapes establish an aseptic barrier minimizing the passage of microorganisms from nonsterile to sterile areas.2 Sterile drapes should be placed on the patient, furniture, and equipment to be included in the sterile field, leaving only the incisional site exposed.5 During the draping process, only scrubbed personnel should handle sterile drapes. The drapes should be held higher than the operating room bed with the patient draped from the prepped incisional site out to the periphery.2 Once the sterile drape is positioned, it should not be moved or rearranged.5 Keep in mind that after the patient and operating room tables are draped, only the top surface of the draped area is considered sterile.1

Principle #3

All items used within a sterile field must be sterile.2,4

Under no circumstances should sterile and nonsterile items/areas be mixed since one contaminates the other.4 Sterilization provides the highest level of assurance that all instruments, sutures, fluids, supplies, and drapes are void of microorganisms.2 The sterility of a package is determined by events, not by time. To ensure sterility, all sterile items need to be inspected for package integrity and sterilization process indicators, such as indicator tape and internal chemical indicators, prior to introduction onto the sterile field.2 If a package has been compromised, it should be considered contaminated and not be used.5

Fluid or air can contaminate a sterile package. When fluid penetrates a sterile package, fluid strikethrough occurs. The fluid creates a vehicle in which migration of microorganisms reach the sterile item. When a sterile packaged item is dropped on the floor, air penetrates the sterile package. The force that is created when the package contacts the floor can cause the sterile barrier to be penetrated by forcing sterile air out and allowing contaminated air and particles into the package.1,3

Principle #4

All items introduced onto a sterile field should be opened, dispensed, and transferred by methods that maintain sterility and integrity.2,4

All sterile items should be dispensed to the sterile field by methods that preserve the integrity of the items and sterile field.1 Nonsterile personnel, usually the circulating nurse, must use good judgement when dispensing sterile items onto the sterile field either by presenting them directly to the scrubbed person or placing them securely on the sterile field.1,2 Sterile items that are tossed onto the sterile field may displace other sterile items, penetrate the drape, or roll off the sterile field causing contamination to occur.1,2

When opening wrapped supplies, the nonsterile person should open the top wrapper flap away from them first, then open the flaps to each side. The last wrapper flap is pulled toward the nonsterile person opening the package.3 This technique of opening a wrapped package ensures that the nonsterile person does not reach over the sterile item inside. All wrapper edges should be secured to prevent flipping the wrapper and contaminating the contents of the sterile package or field.2,5 After a wrapper has been opened, the inside of the wrapper and its contents are considered sterile with the exception of the 1-inch outer edge of the wrapper.1 This 1-inch outer edge of the wrapper is considered the "margin of safety" between sterile and nonsterile. When a package is double wrapped, each institution's policies and procedures determine if one or both wrappers are opened before presentation to the sterile field.5

When opening a peel package, the nonsterile person opens the package by rolling the wrapper over his or her hands and presenting the inner contents of the package to the scrubbed person.5 The package and its contents must be presented in such a way to prevent contamination of the sterile item or the scrubbed person. When determining package content sterility, the inner edge of the heat seal is considered the line separating sterile from nonsterile.

When opening a solution container, the nonsterile person should lift the cap straight up and pour the contents of the bottle into a sterile container. The sterile container is either held by the scrubbed person away from the sterile field or placed near the edge of a sterile waterproof-draped table. Only the top rim of the bottle top and bottle contents are considered sterile once the cap has been removed from the bottle. Therefore, when sterile fluids are dispensed, the entire contents of the bottle must be poured or the fluid remaining in the bottle discarded.1 When solutions are poured onto the sterile field, they should be poured slowly to prevent contamination and fluid strikethrough from splashing.2

Principle #5

A sterile field should be maintained and monitored constantly.2,5

It is the responsibility of the operating room staff to monitor and maintain the sterile field. Sterility can never be absolutely guaranteed, but surgical team members should make every reasonable effort to reduce the likelihood of contamination and be vigilant to breaches in sterility.2 When a breach of sterility occurs, team members must take immediate and appropriate action to correct the break in technique to reduce further risk of contamination. Remember, if there is doubt regarding an item's sterility, consider it not sterile.3

The sterile field should be prepared as close as possible to the time of use.2 The sterility of supplies used during a surgical procedure can be affected by the events taking place within the operating room, and the length of time the items have been exposed to the environment.4 Once set up, the sterile field needs to be monitored constantly. When the sterile field is left unattended, personnel, airborne contaminants, insects, and liquids can contaminate the sterile field.2 Each facility should have policies and procedures that address these issues for the surgical team to follow.

Principle #6

All personnel moving within or around a sterile field should do so in a manner to maintain the sterile field.2

Since the patient is the center of the sterile field, scrubbed personnel should remain close to this area without wandering around the room. This movement can result in contamination of the sterile field.2,4 Scrubbed personnel should move only from sterile areas to sterile areas. When scrubbed personnel change positions, they should maintain a safe distance from each other and always pass each other by turning back-to-back or face-to-face.2 This movement reduces the risk of contamination by ensuring the scrub persons are passing either nonsterile to nonsterile or sterile to sterile.

Scrubbed personnel should remain in the position in which they began the surgery. For example, if the surgery begins with the scrubbed person sitting and is completed with the scrubbed person standing, the portion of the gown that was considered sterile is uncertain.5 Scrubbed personnel should keep their arms and hands within the sterile field at all times to avoid any accidental contact with nonsterile items or areas. Scrubbed personnel must maintain a safe distance when approaching nonsterile objects and personnel. This safe distance or "margin of safety" is important in identifying safe boundaries between sterile and nonsterile areas.

Nonsterile personnel should always remain in nonsterile areas and contact only nonsterile items to prevent contamination of the sterile field. It is important that the nonsterile personnel always face the sterile field on approach and should never walk between two sterile fields.2 This ensures that the sterile area is always being observed and accidental contact is avoided. Just as the sterile scrubbed person must maintain a safe distance from nonsterile areas and persons, nonsterile personnel must always be aware of and maintain a "margin of safety" when approaching sterile fields and scrubbed personnel. And finally, when delivering sterile supplies to the sterile field, the nonsterile team member must always maintain a " margin of safety" between themselves and the sterile field, never contacting or reaching over any portion of the sterile area.5 This "margin of safety" is generally identified as a minimum of 12 inches (30 cm) or more.

Principle #7

Policies and procedures for maintaining a sterile field should be written, reviewed annually, and readily available within the practice setting.2

These recommended practices for aseptic technique should be used as guidelines for developing policies and procedures within the practice setting.2 Introduction and review of policies and procedures should be included in the orientation and ongoing education of all perioperative personnel.2

Training of aseptic technique and practices requires experienced and skilled surgical team members to demonstrate these skills to new and inexperienced personnel. New personnel should be assigned an experienced mentor who will be a good role model and teacher providing leadership and education in perioperative practice.


All surgical team members must practice these principles of aseptic technique to help prevent the transfer of microorganisms into the surgical wound during the perioperative period. It is the responsibility of the surgical team members to develop a strong surgical conscience, adhering to the principles of asepsis and rectifying any improper technique witnessed in the operating room. In addition to the principles of asepsis, proper surgical attire plays an important role in the reduction of surgical site infections by reducing the amount of hair and skin contaminants reaching the sterile field.

The goal of asepsis and aseptic technique is to prevent the transfer of microorganisms into the surgical wound. Preventing surgical site contamination requires the efforts of all trained surgical team members to use their knowledge and experience in aseptic practices to provide their patients with optimal care resulting in positive surgical outcomes.

For references, access the ICT Web site.