Redundant combinations of intravenous antibiotics are used in nearly 8 of 10 hospitals, even though they are very infrequently indicated, said a group of researchers working to promote antimicrobial stewardship in hospitals.
In an article published in the October issue of Infection Control and Hospital Epidemiology, Leslie Schultz, R.N., Ph.D., of Premier Safety Institute in Charlotte, N.C., and colleagues reported that a review of cases from more than 500 U.S. hospitals revealed that about 150,000 days of inappropriate antibiotic therapy were prescribed, at an estimated excess cost of more than $12 million over the 4-year study period. Some 78% of hospitals in the study used the unnecessary drug combinations, they said.
The combination of metronidazole and piperacillin-tazobactam accounted for more than half of the redundant treatments detected in the study, with some 32,500 cases receiving this combination for 2 days or more. Other commonly seen redundant treatments included metronidazole and ampicillin-sulbactam, along with metronidazole and ertapenem, which, together with the metronidazole and piperacillin-tazobactam combination, were seen as responsible for 70% of redundant treatments administered to patients (Infect. Control Hosp. Epidemiol. 2014; 35:1229-35).
In a telephone press conference on Sept. 10, one of Dr. Schultz’s coauthors on the paper, Dr. Arjun Srinivasan of the Centers for Disease Control and Prevention, Atlanta, said that, while concerns about antimicrobial stewardship are not new, the findings came as a surprise. "We would expect the use of these combinations to be vanishingly rare given how often they’re indicated," Dr. Srinivasan said, citing a lack of training in antibiotics as a contributing factor.
"We’ve heard from a lot of clinicians that providers don’t know that piperacillin-tazobactam very effectively kills anaerobic bacteria – but they do know that metronidazole is effective," Dr. Srinivasan said. "People are not as aware as they need to be about what antibiotics kill what bacteria, and we need to make sure people know which antibiotics need to be combined and when – and that with some, you don’t gain anything by adding the second drug. You only increase the risk of side effects."
Another physician taking part in the press conference, Dr. Sara Cosgrove of Johns Hopkins Hospital, Baltimore, agreed. "We have suboptimal training among medical students and house staff about what antibiotics cover what bugs," she said. "We have seen publications suggesting that medical students and residents want more info on antibiotics."
Dr. Cosgrove also noted that changes in hospital work practices may have contributed to the problem. "More people are working in hospitals on shorter shifts, and there are communication issues from one physician to the next. One physician may start an antibiotic and a second physician starts a second. There are many ways we can address the problem of unintended duplicate therapy," she said, including the use of alerts generated when pharmacy receives a request for a redundant drug.
Dr. Srinivasan said that hospitals that have implemented alerts have found them effective. Still, both physicians stressed that whatever the methods used, dedicated antimicrobial stewardship teams in hospitals were essential to ensuring the avoidance of redundant treatments.
"Many hospitals report that they are thinking about having an antimicrobial stewardship program. We’d like to nudge them to actually have one," said Dr. Cosgrove, who is chair of the antimicrobial stewardship committee for the Society for Healthcare Epidemiology of America, which publishes Infection Control and Hospital Epidemiology.
Though Johns Hopkins has had an antimicrobial stewardship team since 2002, most hospitals do not have formal groups in place, she said. The Society for Healthcare Epidemiology of America will publish checklists and guidelines in 2015 to help hospitals set up teams, Dr. Cosgrove said, noting that California has recently passed legislation mandating their creation in all hospitals in that state.
All the coauthors of Dr. Schultz’s study except Dr. Srinivasan are employees of Premier Inc., which is a for-profit research corporation. Dr. Srinivasan reported having no conflicts of interest.