Infection Control Today - 06/2001: Instrumental Knowledge

June 1, 2001

The Care and Handling of Instruments in the Sterile Field

By Christine E. Wilson

Themaintaining of a sterile field in the OR is of utmost importance. Patients arealways at risk for secondary infections, and any procedures and preparation thatcan be done to minimize this should be followed scrupulously.

The Parameters of the Sterile Field

The confines of the sterile field vary, but normally include the back table,mayo stand, draped patient, and a portion of the front of the gowns of thesurgeons and scrub techs. More specifically, the top of the back table, the mayostand, and generally 12 inches beyond the surface of these tabletops isrestricted as the sterile area. When opening containers and preparing suppliesand instruments to be used for the surgical procedure, healthcare workers (HCWs)must be careful not to contaminate them. Thus, these items must be flipped fromthe packages onto the back table when the HCW is standing at least a foot away.

Surgeons and scrub technicians operate within the confines of the sterilearea, while the circulating nurse remains outside of it. The gowns of thosewithin the sterile area are generally considered sterile on the front sideonly--from the waist, or the level of the tabletop, to the shoulders. Theirhands and arms are also considered sterile, up to two inches above the elbow,because this is the area covered during the pre-op sterile scrub. However, theirshoulders, necks, faces, and backs are considered unsterile. Because the back ofeach individual is not sterile, they must be careful when they pass each otherinside the sterile area. For example, they cannot pass one another front toback, because then they have risked contamination. Thus, they must passfront-to-front or back-to-back only.

The incision site of the patient is covered first by sterile towels and thenby a large drape with an opening that exposes the incision site. The patient,the towels, the drape, and the table top all lie within the sterile field.

A surgical consciousness has developed over the years to the point where somesurgeons have become extremely meticulous in maintaining the sterile area. Forexample, Lynette King, RN and manager of Perioperative Services at the MayoClinic in Phoenix, Ariz relates how one doctor she worked with ordered that theentire OR was contaminated when the corner of one drape touched the floor. Thus,they had to tear down everything and recreate a new sterile field in order toavoid any chance of bacteria entering the original sterile field.

Early Pioneers

Louis Pasteur is known as the father of bacteriology. Through his research infermentation and putrefaction in the mid-nineteenth century, he realized thatspontaneous generation was not the end result, but merely a step in the process.He found that if all living germs were destroyed and no new ones were allowed toenter, then fermentation or putrefaction would not occur. He went on to discoverthe causes of diseases such as anthrax, fowl cholera, and rabies, and proceededto create vaccinations against these diseases. He also continued his studies inbacteriology with children suffering from fever in hospitals and discovered thepresence of staphylococci. His research, which won him many honors and muchrecognition, has influenced the study of sterilization throughout history.

Joseph Lister was a British surgeon who discovered antiseptics in 1865. Thisfinding greatly reduced the number of deaths that occurred as a result ofinfections created in the operating room. The principle of antisepsis that hedeveloped grew out of Pasteur's theory that bacteria caused infection. Beforesurgery, Lister sprayed the operating rooms with carbolic acid, because hethought that the infections were caused by dust particles in the air. He thenstarted applying carbolic acid to any of the materials he used for surgery,including instruments and bandages. By 1869, he had already reduced the numberof deaths from surgery by 12%. Thus, his methods eventually became widelyaccepted and he is credited with the beginnings of sterilization in theoperating room.

Practical applications

The members of the surgical team have to be very careful about not breachingthe sterile field. If, for example, an instrument falls on the floor, itimmediately becomes unsterile, and thus, they cannot touch it. It is thecirculating nurse, who operates outside the sterile field, who must pick it up.The HCW picks it up, rinses it off, and has one of two options to follow.According to Sheila Griffin, RN, a traveling OR circulating nurse with MedicalExpress, if the instrument is not critical to the surgical procedure, it is thenput on the dirty case cart, so that it can be collected after the procedure iscompleted. If the instrument is critical to the procedure, however, and there isno other instrument of the same kind and size available, then the circulatingnurse places it in an autoclave for three minutes to resterilize it, and thenreturns it to the OR. All instruments--whether sterile or unsterile--must beaccounted for after the procedure.

According to Pat Menges, RN and director of Perioperative Services at GoodSamaritan Regional Medical Center in Phoenix, Ariz the rules of sterilizationare absolute and the entire team is responsible for maintaining these rules. Itis the job of the circulating nurse, however, to watch over everyone andeverything, and to make sure that the sterile field is not breached. If someonefrom radiology enters the room, for example, the circulating nurse must be surethat this person remains outside the sterile field and doesn't touch anything.Likewise, if the sleeve of the surgeon's gown inadvertently touches the back ofanother team member, the circulating nurse must warn the surgeon that this hashappened. The general rule is when in doubt, throw it out, or change it(referring to a gown, glove, instrument, etc.).

The operating room of the near future

Maintaining the sterile field and ease of operation in the OR of the futurewill become even more effortless than it is today. A number of hospitals on thecutting edge of technology, such as the University of Pittsburgh Medical Center,are now allowing the use of robotic surgical systems to be tested and used.Surgeons are experimenting with the use of robots which not only enhance theprecision and control of the procedure, but also aid the surgeons by being anextra "hand." In addition, they are voice activated. Thus, theoperating team is able to access information from outside the sterile field orto make commands by simply speaking aloud. For example, altering the lightsource, moving the OR table, adjusting the cameras and other monitors, etc., areeasily done with the use of the robotic system, whereas in traditional operatingrooms, these tasks all had to be done manually by personnel either inside oroutside of the sterile field. This eliminates the need for some of thenonsterile assistants or the relaying of information between the surgeon and thestaff outside the sterile environment.

Once these robotic devices become mainstream, the lines between the sterileand nonsterile fields may blur somewhat, but they will not compromise the safetyof the patients. There will still be a circulating nurse on hand to make surethat there will be no breach of security. Thus, the patients can be assured thatthe sterile field will remain intact.



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