The most effective method of gas chemical sterilization presently available is the use of ethylene oxide (ETO) gas. ETO gas sterilization should be used only for material and supplies that will not withstand sterilization by steam under pressure. Never gas-sterilize any item that can be steam-sterilized. The concentration of the gas and the temperature and humidity inside the sterilizer are vital factors that affect the gas-sterilization process.

ETO gas-sterilization periods range from 3 to 7 hours. All items gas-sterilized must be allowed an aeration (airing out) period. During this period, the ETO gas is expelled from the surface of the item. It is not practical here to present all exposure times, gas concentrations, and aeration times for various items to be gas-sterilized. When using an ETO gas-sterilizer, you must be extremely cautious and follow the manufacturer's instructions carefully.

Preparation of Supplies for Autoclaving
Comply with the following guidelines in preparing
supplies that are to be autoclaved.

Inspect all articles to be sterilized, making sure they are clean, in good condition, and in working order.
Wrap instruments and materials in double muslin wrappers or two layers of disposable sterilization wrappers.
When muslin wrappers are routinely used, launder them after each use, and carefully inspect them for holes and tears before use.
When articles are placed in glass or metal containers for autoclaving, place the lid of the container so the steam will penetrate the entire inside of the container.

Arrange the contents of a linen pack in such a way that the articles on top are used first.

Label every item that is packaged for sterilization to specify the contents and expiration date.
Do not place surgical knife blades or suture materials inside linen packs or on instrument trays before sterilization.

The following are specific guidelines for sterilizing instruments, glassware, suture materials, and rubber latex materials.

Instruments:

Wash each instrument after use with an antiseptic detergent solution. When washing by hand, pay particular attention to hinged parts and serrated surfaces. Rinse all instruments, and dry them thoroughly.

Use an instrument washer/sterilizer, if available, to decontaminate instruments and utensils following each surgical procedure.
Following cleaning and decontamination, leave hinged instruments unclasped and wrapped singly or placed on trays for resterilization.
Glassware:

Inspect all reusable glassware for cracks or chips.

Wash all reusable glassware with soap or detergent and water after use, and rinse it completely.
When preparing reusable glass syringes
-match numbers or syringe parts;
-wrap each plunger and barrel separately in gauze; and

-wrap each complete syringe in a double muslin wrapper.
When glassware, tubes, medicine glasses, and beakers are part of a sterile tray, wrap each glass
item in gauze before placing it on the tray.
Suture Material: Suture materials are available in two major categories: absorbable and nonabsorbable. Absorbable suture materials can be digested by the tissues during the healing process. Absorbable sutures are made from collagen (an animal protein derived from healthy animals) or from synthetic polymers. Nonabsorbable suture materials are those that effectively resist the enzymatic digestion process in living tissue. These sutures are made of metal or other inorganic materials. In both types, each strand of specifically sized suture material is uniform in diameter and is predictable in performance.

Modern manufacturing processes make all suture materials available in individual packages, presterilized, with or without a surgical needle attached. Once opened, do not resterilize either the individual package or an individual strand of suture material.

NOTE: The only exception to this rule involves the use of surgical stainless steel. This material is often provided in unsterile packages or tubes. Individual strands or entire packages of surgical stainless steel must be sterilized before use.

Rubber Latex Materials:
Wash rubber tubing in an antiseptic detergent solution.

-Pay attention to the inside of the tubing. Rinse all tubing well and place it flat or loosely coiled in a wrapper or container.
-When packing latex surgical drains for sterilization, place a piece of gauze in the lumen of the tray. Never resterilize surgical drains.

-Never resterilize rubber catheters bearing a disposable label.

-Never resterilize surgeon's disposable (rubber) gloves. These gloves are for one-time use only.
Handling Sterile Articles

LEARNING OBJECTIVE: Recall sterile article handling and surgical hand scrubbing techniques, donning procedure for gowning and gloving, and the steps to clean an operating/treatment room.

When you are changing a dressing, removing sutures, or preparing the patient for a surgical procedure, it will be necessary to establish a sterile field from which to work. The field should be established on a stable, clean, flat, dry surface. Wrappers from sterile articles may be used as a sterile field as long as the inside of the wrapper remains sterile. If the size of the wrapper does not provide a sufficient working space for the sterile field, use a sterile towel. Once established, only those persons who have donned sterile gloves should touch the sterile field. Additionally, the following basic rules must be adhered to:

An article is either sterile or unsterile; there is no in-between. If there is doubt about the sterility of an item, consider it unsterile.
Any time the sterility of a field has been compromised, replace the contaminated field and setup.
Do not open sterile articles until they are ready for use.

Donot leave sterile articles unattended once they are opened and placed on a sterile field.
Do not return sterile articles to a container once they have been removed from the container.
Never reach over a sterile field.
When pouring sterile solutions into sterile containers or basins, do not touch the sterile container with the solution bottle. Once opened and first poured, use bottles of liquid entirely. If any liquid is left in the bottle, discard it.

Never use an outdated article. Unwrap it, inspect it, and, if reusable, rewrap it in a new wrapper for sterilization.

Surgical Hand Scrub
The purpose of the surgical hand scrub is to reduce resident and transient skin flora (bacteria) to a minimum. Resident bacteria are often the result of organisms present in the hospital environment. Because these bacteria are firmly attached to the skin, they are difficult to remove. However, their growth is inhibited by the antiseptic action of the scrub detergent used. Transient bacteria are usually acquired by direct contact and are loosely attached to the skin. These are easily removed by the friction created by the scrubbing procedure.

Proper hand scrubbing and the wearing of sterile gloves and a sterile gown provide the patient with the best possible barrier against pathogenic bacteria in the environment and against bacteria from the surgical team. The following steps comprise the generally accepted method for the surgical hand scrub.

1. Before beginning the hand scrub, don a surgical cap or hood that covers all hair, both head and facial, and a disposable mask covering your nose and mouth.

2. Using approximately 6 ml of antiseptic detergent and running water, lather your hands and arms to 2 inches above the elbow. Leave detergent on your arms and do not rinse.

3. Under running water, clean your fingernails and cuticles, using a nail cleaner.

4. Starting with your fingertips, rinse each hand and arm by passing them through the running water. Always keep your hands above the level of your elbows.

5. From a sterile container, take a sterile brush and dispense approximately 6 ml of antiseptic detergent onto the brush and begin scrubbing your hands and arms.

6. Begin with the fingertips. Bring your thumb and fingertips together and, using the brush, scrub across the fingertips using 30 strokes.

7. Now scrub all four surface planes of the thumb and all surfaces of each finger, including the webbed space between the fingers, using 20 strokes for each surface area.

8. Scrub the palm and back of the hand in a circular motion, using 20 strokes each.

9. Visually divide your forearm into two parts, lower and upper. Scrub all surfaces of each division 20 strokes each, beginning at the wrist and progressing to the elbow.

10. Scrub the elbow in a circular motion using 20 strokes.

11. Scrub in a circular motion all surfaces to approximately 2 inches above the elbow.

12. Do not rinse this arm when you have finished scrubbing. Rinse only the brush.

13. Pass the rinsed brush to the scrubbed hand and begin scrubbing your other hand and arm, using the same procedure outlined above.

14. Drop the brush into the sink when you are finished.

15. Rinse both hands and arms, keeping your hands above the level of your elbows, and allow water to drain off the elbows.

16. When rinsing, do not touch anything with your scrubbed hands and arms.

17. The total scrub procedure must include all anatomical surfaces from the fingertips to approximately 2 inches above the elbow.

18. Dry your hands with a sterile towel. Do not allow the towel to touch anything other than your scrubbed hands and arms.

19. Between operations, follow the same hand- scrub procedure.