Creating and maintaining a sterile field

Sterilization is the process that eliminates all microorganisms-- including bacterial endospores--from instruments, drapes, and other items. A sterile field is an area created by placing sterile towels or surgical surgical drapes around the procedure site and on the stand that will hold sterile instruments and other items needed during the procedure. When a service provider is properly dressed in sterile surgical attire, the provider's sterile area is the only area that should come in contact with the sterile field. Only sterile objects and personnel may be allowed within the sterile field.

• When a sterile field is created around a procedure site, items below the level of the draped client are outside the field and are not sterile.
• A properly gowned and gloved provider's sterile area extends from the chest to the level of the sterile field. Sleeves are sterile from 5 cm above the elbow to the cuff.

Only sterile items are free of potentially harmful microorganisms. Once a sterile object comes in contact with a nonsterile object or person or with dust or other airborne particles, the object is no longer sterile. If even one nonsterile object or person enters the sterile field, the field is no longer sterile. For example, sterile objects become contaminated if you touch the object with your bare hand, if the object comes in contact with dust or other airborne particles, or if the object is held below the level of the sterile field.

To maintain the sterile field:

• Do not place sterile items near open windows or doors.
• Place only sterile items within the sterile field.
• Do not contaminate sterile items when opening, dispensing, or transferring them.
• Consider items located below the level of the draped client to be unsterile.
• Do not allow sterile personnel to reach across unsterile areas or to touch unsterile items.
• Do not allow unsterile personnel to reach across the sterile field or to touch sterile items.
• Recognize and maintain the provider's sterile area.
• Recognize that the edges of a package containing a sterile item are considered unsterile.
• Recognize that a sterile or high-level disenfected (HLD) barrier that has been penetrated (wet, cut, or torn) is considered contaminated.
• Be conscious of where your body is at all times, and move within or around the sterile or HLD field in a way that maintains sterility or HLD status.

High-level disinfection (HLD)

HLD eliminates microorganisms (such as bacteria, viruses, fungi, and parasites), but does not reliably kill the bacterial endospores that cause diseases such as tetanus and gas gangrene. HLD is suitable for instruments and other items that will come in contact with broken skin or intact mucous membranes. A sterile field may contain instruments or other items that were high-level disinfected. All principles of sterile fields also apply to conditions of high-level disinfection. (More information about sterilization and HLD can be found in the Instrument Processing module of this course.)

When in doubt about the sterility of an item or area, consider it to be contaminated. Be conscious of where your body is and how you move around the sterile field at all times.

©2004 EngenderHealth