Post-surgical infection can make recovering from an operation a nightmare. About 600,000 of the 30 million people who have surgery each year develop infections after surgery—increasing their hospital stays, their hospital bills, and even their chance of death. In the 1960s, studies showed that using antimicrobials (medicines to stop the growth of bacteria, pathogens, and other unsavory little creatures) greatly reduced the risk of infection. However, antimicrobials are not always used as they should be. As part of a project to promote the correct practices, doctors from around the country looked at whether or not surgery patients were being treated properly to prevent infection.

What the researchers wanted to know: Are antimicrobials being used properly to prevent infection?

What they did: The researchers looked at medical records from 34,133 Medicare patients who had various types of surgery including coronary artery bypass, vascular surgery, abdominal surgery, hip and knee joint surgery, and hysterectomy. They examined the medical records for procedures that are known to reduce the incidence of postoperative infections: administration of antimicrobials an hour before surgery, adherence to standard guidelines, and discontinuation of the antimicrobial within 24 hours after surgery (which prevents bacteria from becoming resistant to the medicine).

What they found: Only 0.7 percent of the patients did not receive an antimicrobial at all, but for most patients, not all of the risk reduction steps were followed. Patients received a dose of an antimicrobial before surgery about 56 percent of the time, and the medicine was given in accordance with standard guidelines about 93 percent of the time. However, only 41 percent of the patients had their antimicrobials stopped after 24 hours or less. The researchers say that although cardiologists and orthopedic surgeons often like to use antimicrobials for longer than a day after surgery, the published evidence shows that longer-term therapy is no more effective. After surgery, about 8 percent of the patients developed an infection while in the hospital.

What it means to you: If you're undergoing an operation, your risk of postoperative infection is small, though there is a risk. While there is little you can do about the medications you are given before, during, and after surgery, you can be aware of the risk and ask your doctor about it. It is also good to follow good hygienic practices—especially around the incision site, until it heals.

Caveats: Though the researchers used a huge number of cases, all of them were Medicare patients, so the findings may not apply to younger patients. In addition, the researchers found out how many patients developed infections, but they did not look to see if those patients had been given antimicrobials properly to reduce infection.

Find out more: The Centers for Disease Control and Prevention has a PDF file with tips to prevent infection and antimicrobial resistance.

The National Institutes of Health also has a page with links to different topics related to surgery.

Read the article: Bratzler, D.W. et al. "Use of Antimicrobial Prophylaxis for Major Surgery." Archives of Surgery. February 2005, Vol. 140, No. 2, pp. 174-182.

Abstract online: http://archsurg.ama-assn.org