Antibiotic administration is one of the few practices that doesn't fall into infection control science's large gray area ' clinicians have long known that antibiotics were a good method of preventing bacteria from settling in surgical wounds. When researchers looked to hone administration, they readily found that administering antibiotics in the two hours before surgery reduces wound infection risks.

For example, one study that looked at 2,847 patients undergoing elective clean or clean-contaminated surgical procedures found that those who received pre-op antibiotics, rather than only perioperative or post-op antibiotics, had significantly lower SSI risk than the other groups.1 Further, notes another study, failure to administer the first dose of antimicrobial prophylaxis within the two-hour window before incision is associated with two- to six-fold increases in rates of surgical site infection.2 Research has also provided drug guidelines tailored to specific procedures (see "Recommendations for Antimicro-bial Prophylaxis for Adults" on page 17).

Because the over-, under- and misuse of antibiotics occurs 20 to 50 percent of the time ' meaning "errors in antimicrobial prophylaxis for surgical patients [are] one of the most frequent types of medication errors" ' experts are focusing on finding tried-and-true methods for ensuring correct antibiotic prophylaxis.2,3 Here's how to ensure the time it takes to set up an IV is well spent.

A three-point approach
An optimal antibiotic protocol consists of three key practices, says Frances Griffin, RRT, MPA, a director of the Institute for Healthcare Improvement in Cambridge, Mass. Here are the steps, which are also endorsed by the Joint Commission:

• Properly select prophylactic antibiotics using national guidelines;
• administer the antibiotic an hour before the first surgical cut (vancomycin may be started two hours before surgery) and
• discontinue therapy 24 hours after most surgeries and 48 hours after thoracic surgery.

"The first two are heavily tied to preventing surgical site infections," says Ms. Griffin. "Protocols can be a huge help in preventing SSIs if they help these steps happen consistently and reliably."

How often these recommendations are applied is less certain. In 2005, researchers at the Oklahoma Foundation for Medical Quality and other healthcare agencies reviewed 34,113 charts from Medicare inpatients undergoing major surgeries. For the most part, healthcare workers were missing the mark on timing:

• Patients were given the appropriate antibiotic in 92.6 percent of cases;
• antibiotics were administered within one hour of the incision time to 55.7 percent of patients; and
• antibiotics were discontinued within 24 hours of the end of surgery for just 40.7 percent of patients.4

Ronald Lee Nichols, MD, of the department of surgery at Tulane University Health Sciences Center in New Orleans concurs, though he says he's generally seen progress in antibiotic therapy over the last 30 years.5

"The biggest mistakes are people administering antibiotics early, about three to four hours before surgery, or giving too many doses afterward by keeping the patients on them for two to three days," says Dr. Nichols. "But I've seen orthopedic procedures where antibiotics weren't administered until after the tourniquet was on. How is that supposed to help?"

Start with a formula
Recommendations vary by procedure, but accreditation bodies, government agencies and specialty societies have worked to ensure that there is as little contradiction as possible in their guidelines, making them a good starting point for your protocol, says Ms. Griffin.

She recommends an evidence-based process for picking the most appropriate antibiotic agent. The first consideration is what's being operated on.

"If the patient is having abdominal surgery, he'll need different antibiotics than he would for ankle surgery because of the types of microorganisms on each body part," she says, noting that sometimes protocols are the same regardless of setting. "The recommendations for a procedure such as an ENT operation would be similar whether the procedure is done in an inpatient or outpatient setting."

Another factor is whether the patient's natural flora could be a source of infection.

"Clean" procedures, in which the gastrointestinal, gynecologic and respiratory tracts are not entered, can often be done without antibiotics. The infection rate for these tends to be less than 3 percent and whatever infections develop may be due solely to airborne exogenous microorganisms outside your control.6 For other types of surgery, such as clean-contaminated procedures in which the gastrointestinal or respiratory tract is entered under controlled conditions or in which there is a minor break in sterile technique, antibiotics can prevent infections from endogenous flora.7

The key, says Ms. Griffin, is to develop a system, such as a flowchart, for staff to reference. "Based on the type of surgery, the patient automatically should receive the antibiotic on the list after the pharmaceutical evaluation for allergies and accounting for kidney function or reasons to vary dosage," she says.

Follow through in practice
Every facility should design its own system, says Ms. Griffin, because of the wide variation in sizes and structures among surgical facilities.

"The protocol that works in one organization may not work in another," she says. But it's important that you standardize antibiotic administration. Otherwise, "everyone has to do it on their own. They'll have to rely on their memories, and people can forget to write out the instructions or can write them too late so the patient doesn't get the ideal treatment. Standardizing with a protocol eliminates opportunities for error."

A review of the literature indicates that the best way to develop protocols for your institution is to involve representatives from all specialties.8 This review found that protocols are most effective when developed by a multidisciplinary steering team of surgeons, infectious disease specialists, pharmacists, anesthesiologists, microbiologists and nurses. Once you've created the guidelines, you may have to reinforce them by making it easy for staffers to remember what they should be doing. Some tips suggested by the Institute for Healthcare Improvement as part of its 100,000 Lives Campaign:

• Use standing orders specifying antibiotic, timing, dose and discontinuation.
• Stock only standard doses and standard drugs that reflect national guidelines.
• Reassign dosing responsibilities to anesthesia or the holding area nurse to improve timeliness.
• Use visible reminders, checklists or stickers.
• Get pharmacy and infection control staff involved to ensure appropriate timing, selection and duration.
• Verify the administration time during "time out" or pre-procedural briefing so you can take action if the antibiotic was not administered.

While the short half-life of many antibiotics makes well-timed pre-op administration important, there isn't much benefit to providing them for more than a day after surgery. Most surgeons continue therapy at least 24 hours post-op, though at present no evidence proves the efficacy of continuing anti-biotics beyond discharge.9 In fact, one recent study found that administering a single 1g cefazolin dose with anesthesia proved as effective in preventing SSIs as a 24-hour post-operative protocol.10

Finish with tracking
A recently published study is a good example of the positive change you can effect by following recommendations: Baystate Medical Center in Spring-field, Mass., reduced SSIs after cardiac and vascular procedures from 3.8 percent to 1.4 percent ' a 64 percent reduction ' and after all other procedures from 1.8 percent to 1.4 percent ' a 22 percent reduction.3 As you can see, even if your infection rates are already low, you have much to gain by properly adhering to a right-antibiotic, right-time, right-discontinuation protocol.

References
1. Classen DC, et al. "The timing of prophylactic administration of antibiotics and the risk of surgical-wound infection." N Engl J Med. 1992 Jan 30;326(5):281-6.
2. Burke JP. "Maximizing appropriate antibiotic prophylaxis for surgical patients: an update from LDS Hospital, Salt Lake City." Clin Infect Dis. 2001 Sep 1;33 Suppl 2:S78-83.
3. Kanter G, Connelly NR, Fitzgerald J. "A System and Process Redesign to Improve Antibiotic Administration." Anesth Analg. 2006; 103:1517-21.
4. Bratzler DW, et al. "Use of antimicrobial prophylaxis for major surgery." Arch Surg. 2005;140:174-82.
5. Nichols RL. Preventing Surgical Site Infections. Clin Med & Res 2004;2:115-8.
6. Nichols RL. "Preventing Surgical Infections: A Surgeon's Perspective." Emerging Infectious Diseases. Mar-Apr 2001;7:2.
7. Nichols RL. "Prevention of infection in high risk gastrointestinal surgery." Am J Med. 1984;76:111-9.
8. Khan SA, Rodrigues G, Kumar P and Rao PG. "Current challenges in adherence to clinical guidelines for antibiotic prophylaxis in surgery." J Coll Physicians Surg Pak. 2006;16(6):435-7.
9. Woods RK and Dellinger EP. "Current guidelines for antibiotic prophylaxis of surgical wounds." Am Fam Physician. 1998;57:1-14.
10. Fonseca SNS, et al. "Implement-ing 1-dose antibiotic prophylaxis for prevention of surgical site infection." Arch Surg. 2006;141:1109-13.