Have you ever stopped to observe the number of ways patients' skin is prepped for surgery in your facility? With dozens of prepping solution options, as many techniques as there are staff performing preps, and inconsistencies in body hair removal and pre-operative antiseptic showering, the permutations are seemingly endless. That wouldn't be too much of a concern if prepping were simply a matter of rubbing some solution on a patient and giving the surgeon a thumbs up for the incision.

But prepping correctly - according to standardized protocols based on recommended practices - is critical for preventing surgical site infections. With this quiz, you can find out what you know (and what you don't) while getting a crash course in the available evidence. The first step toward standardization, after all, is education.

A recent review of six randomized, controlled trials comparing pre-operative antiseptic showering preparations for efficacy found that

A. pre-op showers definitively reduce SSI rates.
B. pre-op showers have no effect on SSI rates.
C. pre-op showers actually increase SSI rates.

Answer: B. pre-op showers have no effect on SSI rates. The six studies covered by the review, published April 19, 2006, in the Cochrane Database System Review, examined more than 10,000 participants. Based on this large sampling, researchers found that bathing with chlorhexidine compared with a placebo didn't result in a statistically significant reduction in SSIs; that there was no difference in SSI risk between using chlorhexidine and bar soap and that there was no difference in the post-op SSI rate between patients who washed with chlorhexidine and those who didn't wash at all.

"This review provides evidence of no benefit for pre-operative showering or bathing with chlorhexidine over other wash products, to reduce surgical site infection," conclude the authors. "Efforts to reduce the incidence of nosocomial surgical site infection should focus on interventions where effect has been demonstrated."

Still, the authors acknowledge that using an "antiseptic skin wash product is a well-accepted procedure for reducing skin bacteria." Further, the CDC has labeled pre-op antiseptic showers a 1B recommendation ("strongly recommended for implementation and supported by some experimental, clinical or epidemiological studies and strong theoretical rationale"), writing in its "Guideline for the Prevention of SSI" that "a pre-operative antiseptic shower bath decreases skin microbial colony counts." The agency got its evidence from a study of more than 700 patients who received two pre-op antiseptic showers in which chlorhexidine reduced bacterial colony counts ninefold, while povidone-iodine or triclocarban-medicated soap reduced colony counts by 1.3- and 1.9-fold each. Other studies corroborate this one's findings, says the CDC, which also recommends repeated antiseptic showers because several applications of chlorhexidine-gluconate-containing products are needed to ensure effectiveness.

However, while it's proven that the solutions themselves will reduce colony counts, there's no definitive evidence that such pre-op showers are effective in practice. Poor modes of delivery that don't sufficiently direct the flow of the liquid, varied and often-inadequate contact times, and patients' own movement limitations all hamper efficacy. Further, it's hard to pin down the exact factor - if there is one - responsible when an SSI does develop. The flip side of that argument is that every effort you make may contribute to SSI prevention. The best way, then, to help ensure effectiveness of the pre-op antiseptic wash is to perform it in a controlled environment.

Of the following hair removal methods, which has been shown to have the lowest infection rates?

A. depilatory
B. clippers
C. shaving
D. depilatory and clippers

Answer: A. depilatory. According to a study cited by the CDC's "Guideline for Prevention of SSI," patients whose hair had been removed by razor shave had surgical site infection rates of 5.6 percent, whereas those who had had hair removed by depilatory presented with SSI rates of 0.6 percent. A literature review by Kjonniksen and colleagues published in the April 2002 issue of AORN Journal found that shaving was associated with higher rates of SSIs (2.5 percent) than either manual (1.7 percent) or electrical (1.7 percent) clipping.

Timing is also a key determining factor when it comes to SSI rates; it's well known that removing hair around the surgical site 24 hours before surgery increases the potential risk for infection, and that the chance of infection increases the further out from surgery you shave or clipper a patient. According to the study cited by the CDC guidelines, patients who shave 24 hours in advance of surgery have infection rates of 3.1 percent and those who shaved more than 24 hours before their procedures had SSI rates of 20 percent. This is probably because microorganisms have had time to colonize the operative site under the skin, thanks to the tiny nicks created by the razor, and prepping solution won't necessarily infiltrate all those holes. Further, patients who clip hair the night before surgery also have significantly increased risk for post-operative SSIs compared to patients whose hair is clipped in the OR: 7.5 percent versus 3.2 percent.

Although infection rates with depilatories are lower than those with clippers, the creams can sometimes cause hypersensitivity reactions and it's not worth risking that undesirable side effect, according to the CDC. In light of this, it's best to avoid hair removal altogether: Patients who had no hair removed had the same 0.6 percent infection rate as patients who had hair removed by depilatory, according to the "Guideline for the Prevention of SSI." The level 1A CDC recommendation basically says that, if you absolutely must remove hair because it will somehow interfere with the surgery itself, you should clip hair immediately pre-op (but not in the OR) using electric clippers. (For tips on getting surgeons and staff alike to change their habits, see "4 Evidence-based Prevention Measures" on page 78 of the June issue and "Rid Your Rooms of Razors" on page 42 of the 2007-08 Manager's Guide to Infection Control.)

True or false: The best method for applying prepping solutions is circumferentially and in concentric circles.

Answer: false. The old edict to begin at the incision site and move out in concentric circles no longer holds in all cases. Sure, if you're using betadine and sponges, this is the way to go - but with the advent of formulations composed of various mixes of CHG, iodophors, alcohol, triclosan and PCMX have come new and more convenient modes of delivery.

When using these increasingly popular all-in-one delivery systems, it's best to carefully follow the manufacturers' instructions. This is because they all go on differently (repeated back-and-forth strokes, single strokes, circular strokes), have different application times (a few seconds to a few minutes) and have different drying times (especially important to note with alcohol-containing preps). It's hard to keep all the methods straight, so I recommend you limit your prepping inventory to the formulations you need to compensate for allergies and sensitivity reactions. Just as importantly, you need to educate OR staff on prepping according to the specific instructions for the formulations you carry.

Here are a few other tips to keep in mind with regard to technique.

• No recycling. Discard the sponge or single-use applicator when you have finished using it according to the prep manufacturer's instructions. Don't reuse a sponge or applicator on the incision site; if you really feel a touch-up is needed, use a new sponge or applicator.
• Be thorough. Prep all areas that will be exposed during surgery to prevent skin flora in the surrounding area from migrating to the surgical site. Use a cotton swab to clean areas such as the navel before prepping if you have to. Go over the problem areas - those where microorganisms are going to be particularly anxious to settle, such as open wounds, perineal areas or the area around a colostomy - last. If you'll be draping, be sure to prep a couple extra inches past the exposed area to ensure full coverage.
• Follow instructions. I'm not repeating myself: I'm talking about following manufacturers' instructions for drapes. You might need to wait for the prep to dry before placing the drape, or vice versa. So check those directions for use.
• Stay out of the pool. Avoid applying excessive amounts of prep, which can drip off the patient and pool under him. Not only can this irritate or burn skin, it can interfere with the application of a return electrode and, in the case of alcohol-containing agents, pose a fire hazard. Be particularly careful about following the recommended drying times of preps with alcohol - I know everyone in the OR's in a rush, but 30 more seconds isn't too long to wait if it means you'll be able to safely use the active electrode.

Scrub, paint, write
As with all tasks you carry out, you should document the prep from start to finish, including the pre-op skin assessment, hair that is removed, method and time of removal, cleansing and prepping agents used, the name of the staffer who performed the prep and whether any reactions to the prep occur.