Principles of Sterile Technique
So, what are the principles of sterile technique?
1. ONLY STERILE ITEMS ARE USED WITHIN THE STERILE FIELD.
Some items such as linens, sponges, or basins may be obtained from stock supply of sterile packages. Others, such as instruments, may be sterilized immediately proceeding the operation and removed directly from the sterilizer to the sterile tables. Every person who dispenses a sterile article must be sure of its sterility and of its sterile until used. Proper packaging, sterilizing, and handling should provide such assurance. If you are in doubt about the sterility of anything consider it not sterile.
Known or potentially contaminated items must not be transferred to the field, for example: a. If sterilized package is found in a nonsterile workroom b. If uncertain about actual timing of operation of sterilizer. Items processed in suspect load considered unsterile. c. If unsterile person comes into close contact with a sterile table and vice versa d. If sterile table or unwrapped sterile items are not under constant observation e. In sterile package falls to the floor; it must be than discarded.
2. GOWNS ARE CONSIDERED STERILE ONLY FROM THE WAIST TO SHOULDER LEVEL INFRONT AND THE SLEEVES.
When wearing a gown, consider only the area your can see down to the waist as the sterile area. The following practices must be observed: a. Sterile person keep hands in sight and at or above waist level. b. Hands are kept away from the face. Elbows are kept close to sides. Hands are never folded under arms because of perspiration in the axillary region. c. Changing. Table levels is avoided. If a sterile person must stand on a platform to reach the operative filed, the area of the gown below waist must not brush against sterile tables or draped areas. d. Items dropped below waist level are considered unsterile and must be discarded.
3. TABLES ARE STERILE ONLY AT TABLE LEVEL.
The result is that a. Only the top of the table with the sterile drape is considered sterile edges and sides of drape extending below table level are considered unsterile. b. Anything falling or extending over table edge, such as a piece suture, is unsterile. Scrub nurse does not touch the part hanging below the level. c. In unfolding sterile drape, the part that drops below the table surface is not brought back up to table level.
4. PERSONS WHO ARE STERILE TOUCH ONLY STERILE ITEMS OR AREAS; PERSONS WHO ARE NOT STERILE TOUCH ONLY UNSTERILE ITEMS OR AREA.
For example: a. Sterile team members maintain contact with sterile field by means of gowns and gloves. b. Nonsterile, circulating nurse does not directly come into contact with the sterile field. c. Supplies for sterile team members reach them by means of the circulating nurse who opens wrapper on sterile package.
5. UNSTERILE PERSONS AVOID REACHING OVER A STERILE FIELD; STERILE PERSONS AVOID LEANING OVER AN UNSTERILE AREA.
For example: a. Unsterile circulating nurse never reach over a sterile field to transfer sterile items. b. In pouring solution into sterile basin, circulating nurse holds only lip of bottle over basin to avoid reaching over sterile area. . Scrub nurse sets basins or glasses to be filled at edge of the sterile table; circulating nurse stands near the edge of the table to fill them d. Circulating nurse stands at a distance from the sterile field to adjust light over it to avoid microbial flowout over field. e. Surgeon turns away from sterile field to have perspiration removed from brow. f. Scrub nurse drapes a nonsterile table toward self first to protect gown. g. Scrub nurse stands back from nonsterile table when draping it to avoid leaning over an unsterile area.
6. EDGES OF ANYTHING THAT ENCLOSES STERILE CONTENTS ARE CONSIDERED UNSTERILE.
Boundaries between sterile and unsterile areas are not always rigidly defined, for example, the edges of wrappers on sterile packages are caps on solution bottles are unsterile. The following precautions should be taken: a. In opening sterile packages, a margin of safety is always maintained. Ends of flaps are secured in hand so they do not dangle loosely. The last flap is pulled toward the person opening package thereby exposing package contents away from nonsterile hands. b. Sterile persons lift contents from packages by reaching down and lifting then straight up, holding elbows high. . Steam reaches only the area within the gasket of a sterilizer. Instrument trays should not touch the edge of the sterilizer. d. Flaps on the peel-open package should be pulled back, not torn, to expose sterile contents. Contents should be flipped or lifted upward and not permitted to slide over edges. Inner edge of the heat seal is considered the line of demarcation between sterile and unsterile portion. e. If sterile wrapper is used as a table cover, it should be covered amply cover the entire table surface. Only the interior and surface level of the cover are considered sterile. After bottle is opened, contents must be used or discarded. Cap cannot be replaced without contaminating pouring edge.
7. STERILE FIELDS IS CREATED AS CLOSE AS POSSIBLE TO TIME OF USE.
Degree of contamination is proportionate to length of time sterile items are uncovered and exposed to the environment. Precautions must be taken as followed: a. Sterile tables are set up just prior to the operation. b. It is difficult to uncover a table of sterile tables for later use is not recommended.
8. STERILE AREAS ARE CONTINUOUSLY KEPT IN VIEW.
Inadvertent contamination of sterile areas must be readily visible.
To ensure this principle: a. Sterile persons face sterile areas. b. When sterile packs are opened in a room, or a sterile field is set up, someone must remain in the room to maintain vigilance.
9. STERILE PERSONS KEEP WELL WITHIN THE STERILE AREA.
Allow a wide margin of safety when passing unsterile areas and following these rules: a. Sterile persons stand back at a safe distance from the operating table when draping the patient. b. Sterile persons pass each other back to back c. Sterile persons turn back to nonsterile persons or area when passing. d. Sterile persons faces sterile area to pass it. e. Sterile persons ask nonsterile individual to step aside rather than risk contamination. f. Sterile persons stay within and around a sterile field. They do not walk around or go outside room. g. Movement within and around a sterile area is kept to a minimum to avoid contamination of sterile items or persons.
10. STERILE PERSONS KEEP CONTACT WITH STERILE AREAS TO A MINIMUM.
The following rules are observed. a. Sterile persons do not lean on sterile tables and on the draped patient. b. Sitting or leaning against a nonsterile surface is break in technique. If the sterile team sits to operate, they do so without proximity to nonsterile area.
11. UNSTERILE PERSONS AVOID STERILE AREA.
A wide margin of safety must be maintained when passing sterile areas by following these rules: a. Unsterile persons maintain at least one foot (30cm) distance from any area of the sterile field. b. Unsterile persons face and observe a sterile area when passing it to be sure they do not touch it. c. Unsterile persons never walk between two sterile areas, e. g. between sterile instrument tables. d. Circulating nurse restricts to a minimum all activity near sterile field.
12. DESTRUCTION OF INTEGRITY OF MICROBIAL BARRIERS RESULTS IN CONTAMINATION.
Integrity of a sterile package of sterile drape is destroyed by perforation, puncture or strike-through. Strike-through is soaking of moisture through unsterile layers or vice versa. Ideal barrier materials are abrasion resistant, impervious to permeation by fluids or dust that transport microorganisms. The integrity of a sterile package, its expiration date, and appearance of process monitor must be checked for sterility just prior to opening. To ensure sterility: a. Sterile packages are laid on dry surface. b. If sterile package becomes damp or wet, it is re-sterilized or discarded.
A package is considered nonsterile if any part of it comes in contact with moisture. c. Drapes are placed on a dry field. d. If solution soaks through sterile drape to nonsterile area the wet area is covered with impervious sterile drape or towels. e. Packages wrapped in muslin or paper are permitted to cool, after removal from the sterilizer to avoid steam condensation and resultant contamination. f. Sterile items are stored in clean dry areas. g. Sterile packages are handled with clean dry hands. h. Undue pressure on sterile packs is avoided to prevent forcing sterile air out and pulling unsterile air into the pack.
13. MICROORGANISMS MUST BE KEPT TO AN IRREDUCIBLE MINIMUM.
Perfect asepsis in an operative field is an ideal to be approached; it is not absolute. All microorganisms cannot be eliminated, but this does not obviate necessary for strict sterile technique. It is generally agreedthat: a. Skin cannot be sterilized. Skin is a potential source of contamination in every operation. Inherent body defenses usually can overcome the relatively few organisms after patient’s skin preparation. Organisms on the hands and arms of the operating team are a hazard. All possible means are used to prevent entrance of microorganisms into wound.
Preventive measures included: I. Transient and resident flora areremoved from skin around operative site of patient and the hands and arms of sterile team members by mechanical washing and chemical antisepsis. II. Gowning and gloving of operating team is accomplished without contamination of sterile exterior of gowns and gloves. III. Sterile gloved hands do not directly touch skin and then deeper tissue. Instruments used in contact with the skin discarded and not reused. IV. If glove is pricked or punctured by needle or instruments, glove is changed immediately. Needle or instrument is discarded from the sterile field. b.
Some areas cannot be scrubbed. When the operative field includes the mouth, nose, throat, or anus, the number of microorganisms present is great. Various parts of the body, such as the gastrointestinal tract and vagina, usually are resistant to infection from flora that normally inhabit these parts. However, the following steps may be taken to reduce the number of microorganisms present in these areas and to prevent spreading this contamination. c. Infected areas are groosly contaminated. The team avoids spreading the contamination. d. Air is contaminated by dust and droplets. Environmental control measures are necessary.