Can We Revisit Cataract Surgery Sterile Technique?
Surgeons question whether many of the recommended protocols are necessary.
BY ROCHELLE NATALONI, CONTRIBUTING EDITOR

Perioperative sterility standards exist to protect patients, surgeons and operating room personnel from potential physical harm. While it seems that such a basic aim would be immune from criticism, some ophthalmic surgeons say that, in the case of cataract surgery, adherence to what are often superfluous protocols is simply another example of defensive medicine in an overly litigious society.

Examples of standards that may have been appropriate in the early days of cataract surgery but are arguably of limited value today include autoclaving surgical instruments rather than sterilizing them with the faster flash technique, and requiring a visitor into an ambulatory surgery center (ASC) operating room (OR) to don a sterile gown and booties. Critics pose questions such as: "If flash sterilization is acceptable in some situations, why isn't it acceptable in every situation, and is scrubbing prior to cataract surgery -- where the incision is measured in millimeters -- equally as crucial as it is prior to general surgery where the wounds are significantly larger?"

Infection control and sterilization experts say some facilities flash sterilize single instruments that have become contaminated; others routinely flash everything; but most follow protocols that are somewhere in between. If done correctly, flash sterilization reportedly meets two crucial surgery parameters: safety and efficiency. Despite the technique's ability to safely and efficiently do the job, the Association of Operating Room Nurses' (AORN) Recommended Practices for Sterilization in the Practice Setting indicates that flash sterilization should only be used when there is insufficient time to sterilize an item by the preferred prepackaged method and only in carefully selected situations when certain parameters are met. (2004 Standards, Recommended Practice and Guidelines).

Surgeons also question the discrepancy between the time needed to sterilize various instruments and devices because the distinction has a direct effect on turnaround time. Why is 3 minutes all it takes for some instruments, while others need to be sterilized for 10 minutes? The simple answer is that porous items take longer to sterilize. For a more complete explanation, see the Association for the Advancement of Medical Instrumentation's (AAMI) report titled Flash Sterilization: Steam Sterilization of Patient Care Items for Immediate Use (http://www.aami.org). (See also "Minimum Flash Sterilization Exposure Times," on the next page.)

As far as pre-op scrubbing, according to at least
two studies, (J Hosp Infect. 1997 May;36(1):49-65 and British Journal of Ophthal. 2004;88:438-439), waterless alcohol-based gel formulas are quicker and either as effective or more effective surgical hand preparations than detergent-based antiseptic.

Another protocol that's often questioned is the need for rubber gloves during cataract surgery. "What evidence is there that scrubbing reduces the risk of endophthalmitis after cataract surgery?" asks Richard Mackool, M.D., director of Mackool Eye Institute, Astoria, N.Y. "The answer is that there is none, and I frankly doubt that such a benefit exists. We wear sterile gloves even though we hardly ever suture anymore, which essentially negates the risk of penetrating a glove with a needle during the procedure, and it's a stretch to imagine a needle could penetrate a glove without some significant sensory feedback to the surgeon," says Dr. Mackool. Furthermore, he adds, "The highly unlikely possibility of penetrating a glove with a needle has been used to justify scrubbing, and anyone who believes that scrubbing sterilizes the hands is, in the words of a Lancet editorial of which I am particularly fond, 'either a fool or a knave or both.' " Perhaps most important of all, he says, "The best studies indicate that the source of the bacteria involved in endophthalmitis is most commonly the patient's own conjunctival/lid flora anyway."

The Thinking Behind the Questions

An alphabet soup of associations, including AORN and AAMI as well as the American Association for Accreditation of Ambulatory Surgical Facilities (AAAASF), promulgates practice guidelines to help facilities retain a sterile OR environment. Some of the guidelines address optimum equipment sterilization times and techniques, others address variables such as scrubbing, draping and traffic patterns. Representatives of these associations are quick to point out that the guidelines are voluntary, and that they are updated frequently to take new developments, such as research, into account. However, while it is true that these guidelines are voluntary, some form of a guideline is essentially mandatory because facility credentialing tends to hinge on the adoption of a protocol designed to protect patients and staff.

The problem, say some ophthalmologists, is that the guidelines do not differentiate between specialties, which means that the infection control and sterility guidelines are essentially the same for cataract extraction as they are for kidney transplant. As cataract surgery has distinguished itself from other more invasive general surgery procedures by evolving into a brief and minimally invasive technique, the concomitant OR sterility protocols that ophthalmic surgeons are expected to adhere to have changed little, if at all.

Los Altos, Calif.-based cataract surgeon David F. Chang, M.D., says in community hospitals, standard OR protocols are set up to cover a broad range of surgeries for all the different specialties, and facility administrators are reluctant to depart from these protocols because of liability concerns if they make exceptions.

"If a patient were to go blind from an infection, then any deviation from standard protocols could be questioned by a malpractice attorney," says Dr. Chang. "Whether there is any scientific merit to each step in the protocol is beside the point. What matters in court is whether the surgery center did or did not follow 'community standards.' A lot of this is defensive medicine." Dr. Chang is a clinical professor of ophthalmology at the University of California in San Francisco.

"We know from molecular biological studies that the pathogens that cause infectious post-cataract endophthalmitis nearly always come from the patients' own conjunctiva and lids, and that true nosocomial infections are extremely rare," he continues. "So there are many routine practices whose value could be questioned, such as full-body draping of the patient, redraping the instrument table and regowning the surgical team for each case, the need for repeated hand washing and so forth. However, because of the rarity of post-cataract endophthalmitis, it would be difficult to prove any of this in a randomized trial. We haven't even been able to scientifically demonstrate whether topical antibiotic prophylaxis is necessary. Given the speed of cataract surgery and the small incision size, it would seem that the risk of nosocomial infection would be much less than for abdominal or orthopedic surgery."

However, because changing standard OR practices in the United States would raise medical-legal concerns, it's more likely that answers will emerge elsewhere. For instance, says Dr. Chang, in India where there are more than 10 million blind patients in need of cataract surgery, cost and efficiency, as opposed to legal concerns, are the guiding factors. "With a limited budget and a limited number of surgeons, the number of people that can receive cataract surgery depends on a facility's ability to do the surgery rapidly at low cost. To do that they must eliminate all superfluous practices," he explains.

For example, the Aravind Eye Hospital System, which comprises five facilities throughout Southern India, is one of the best international models of how to perform high-volume, low-cost cataract surgery with excellent outcomes and low complication rates. "They do more than 200,000 cataract cases a year, 70% of which are provided to nonpaying charity patients," says Dr. Chang. "Success on this scale is accomplished in part because they've made a science out of streamlining cataract surgery, and achieving the best possible results while minimizing the cost. Aravind's endophthalmitis rate is less than one in 1,000, which is comparable to U.S. surgery centers. At their newest hospital, they had only one infection in their first 9,000 phaco cases."

At Aravind, flash sterilization of surgical instruments is standard; they use the same balanced salt solution irrigation bottle for multiple patients; four surgeries are performed simultaneously in the same OR; and at any given time a dozen patients in their street attire may be sitting in the OR waiting for their turn to have surgery, according to Dr. Chang, who has visited Aravind. Rather than changing their gloves or gowns between cases, the surgical staff wipe their gloved hands with chlorhexidine solution.

"Despite all of these departures from our standard protocols, they have shown that the infection rate is no higher than ours in the U.S.," says Dr. Chang. "Does that prove that the protocols we rely on are unnecessary? Absolutely not, but it should give us cause to consider that a lot of the things that we're doing are probably adding unnecessarily to the cost of the procedure either in the form of disposables or in the form of lengthier delays in our turnaround time," he says.

With less than 1% of the country's ophthalmic manpower, Aravind performs about 5% of all cataract surgeries in India. "Here you have a center that's doing huge volume (up to 400 surgeries a day) and yet is able to electronically track its results and infection rate very carefully using custom software. This has allowed them to confirm that these cost-saving measures are not compromising care," says Dr. Chang.

What About ASCs?

While surgeons who own ASCs would be expected to have autonomy in setting their own surgery sterility protocols, it's often the ASC administrator who sets the tone. Interestingly, ASC administrators, who are often former OR nurses, tend to incorporate AORN's voluntary recommended practices into the ASCs that they run. Because of the surgeon's personal investment in a free-standing facility, the specter of litigation might influence practice patterns here even more than in the hospital setting.

Karl G. Stonecipher, M.D., who performs all of his surgeries at Southeastern Eye Center, in Greensboro, N.C., says that budget may have just as much influence on these types of decisions. While he wonders if some of the recommended guidelines are based more on tradition than science, he notes, "When trying to weigh costs vs. benefits, any defensive medical mode will produce significant increases in cost."

Paul Koch, M.D., of Koch Eye Associates in Warwick, R.I., says the one-size-fits-all recommended guidelines simply don't add up from a practical standpoint. "When visitors come into the OR, they have to put on scrubs and booties and a hat and mask, but if a technician comes in to look at a thermostat, all that's required is that he put a jumpsuit on over his clothes. It just doesn't make sense," he says.

According to AORN's Recommended Practices for Traffic Patterns in the Perioperative Practice Setting: "Persons in the restricted area [which includes the OR] are required to wear full surgical attire and cover all head and facial hair, including sideburns and necklines. Nonscrubbed personnel should wear long-sleeved jackets that are buttoned or snapped closed during use. Masks are required where open sterile supplies or scrubbed persons are located." It goes on to say, "Persons from other departments (and this would refer to the technician mentioned earlier) entering the restricted area of the surgical suite for a brief time for a specific purpose may don a coverall suit designed to totally cover outside apparel." The distinction appears to be the length of time the person is in the OR as well as proximity to the sterile field and to scrubbed personnel.

Considering the length of time the average cataract patient is in the OR, and the questionable value of scrubbing, this distinction could be considered moot. "There is no authoritative source asking the important questions because no one wants to go out on a limb and make these standards less rigorous regardless of the absence of scientific proof of their worth," says Dr. Koch.