j. Whenever microorganisms cannot be eliminated from a field, they should be kept to an absolute minimum.

Although absolute asepsis in an operative field cannot be reached, every effort is made to control sources of possible contamination.

(1) Skin cannot be sterilized. Skin normally harbors staphylococcus and other organisms; however, any agent capable of sterilizing skin will also destroy it. The skin of the patient, as well as that of members of the “sterile” team, is therefore a potential source of contamination in every operation. However, this does not remove the need for strict aseptic technique. Defenses within the patient’s body will usually overcome the relatively few organisms left on the skin when the following protective measures are carried out.

(a) The patient’s skin is given a shave and scrub just prior to surgery and is again thoroughly cleansed in the operating room just prior to the incision.

(b) As much of the operative area is cleansed as is feasible and the surrounding skin is scrubbed.

(c) Some areas cannot be scrubbed vigorously. Mucous membranes are gently prepped since scrubbing would damage the tissue. When the site of operation is the mucous membrane of the nose, mouth, throat, or anus, the number of microorganisms present is great. However, these parts of the body do not usually become infected by organisms that normally inhabit them.

(d) When scrubbing the patient’s skin, a sponge is used only once for prepping an area. Once the sponge is removed from contact with the skin, the sponge is discarded into a kick bucket.

(e) All of the patient’s skin area except the site of incision is covered with sterile drapes.

(f) Sterile towels or other sterile material may be used to cover the skin after the incision is made. The reason for this additional precaution is to protect the surgical wound from the waste products continually excreted by the skin. In addition, airborne organisms continuously pose a threat of contaminating the incision.

(g) When the knife used for the skin incision is no longer needed, the scrub isolates it from other items on the sterile field.

(h) The skin of operating room personnel is another source of contamination. They follow rigid steps in scrubbing their hands and arms using brushes and detergents and adhering to strict technique. This is done to remove the maximum number of organisms. When drying their hands, sterile hand towels should not touch their scrub clothes.

(2) The cap worn on the head of team members should completely cover the hair to prevent particles of dandruff or hair from falling on the sterile field or in the room.

(3) Infected areas are grossly contaminated. All team members should avoid scattering the contamination.

(4) The air is usually contaminated by dust and droplets.

(a) Team members are required to wear a mask covering the nose and mouth during an operative procedure. The mask must cover the mouth and nose entirely and be tied securely to prevent venting. The strings should not be crossed when tied because the sides of the mask will gap. A pliable metal strip is inserted in the top hem of most masks to provide a firm contour fit over the bridge of the nose. This strip also helps prevent fogging of eyeglasses. Air should pass only through the filtering system of the mask.

Masks should be either on or off. They should not be saved from one operation to the next by allowing them to hang around the neck or by tucking them into a pocket. Bacteria that have been filtered by the mask will become dry and airborne if the mask is worn necklace fashion. By touching only the strings when removing the mask, contamination of the hands will be reduced. Masks should be changed between procedures and sometimes during a procedure, depending on the length of the operation and the amount of talking done by the surgical team.

(b) When possible, the respiratory tract of the patient should be isolated from the incision. In some cases, isolation is achieved by using the anesthesia screen. This serves as a barrier between the incision and the respiratory tract.

(c) Team members should not talk except when essential. Silence is even better than masking to reduce the number of organisms spread from nose and throat.

(d) Team members should avoid sneezing and coughing.

(e) Persons who have colds or any active infection should be excluded from the operating room.

(f) Main corridors are considered to be contaminated areas; therefore, doors from corridors into the operating rooms should be kept closed. Also, sterile items without wrappers should not be carried through corridors.

(g) Walking through and around the operating room should be kept to the necessary minimum.

(h) All dusting should be damp-dusting with a germicide solution. Floors should be wet-vacuumed between cases as well as at the end of the day. Dry dusting and dry-mopping should be avoided in the operating room since the dust created by these methods would continue to settle or float in the room for hours.

(i) The bedclothes over the patient should be handled gently when he is being transferred to the operating table in order to avoid throwing lint off into the air. Local policy may require bedclothes to be removed/replaced prior to the entry in the operating room; nevertheless, the patient should be covered with a cover sheet at all times.

(j) Dressings removed from a wound should be placed at once in a bag and the bag should be closed and discarded. Drainage that is left exposed to the air may become dried, thus enabling the infectious organisms in it to become airborne and be carried to other parts of the surgical suite and the hospital to infect others.