Surgery antibiotics under scrutiny

THE prescribing habits of surgeons have come under scrutiny, as two new studies suggest perioperative antibiotic prophylaxis is often prescribed inappropriately.

The results of a multicentre single-day hospital-wide point prevalence survey, published online by the MJA, examined antibiotic prescribing at eight children’s hospitals across Australia, finding 40% of surgical patients received at least one antimicrobial prescription deemed “inappropriate” by infectious diseases physicians and/or pharmacists. (1)

The most common reason prescribing was deemed inappropriate was continuing perioperative prophylaxis for longer than 24 hours.

The study results are similar to the findings in adults from the National Antimicrobial Prescribing Survey 2013 results, released last week, which showed 42% of antimicrobial prescriptions in surgical patients were for longer than 24 hours, even though best practice is less than 5%. (2)

The MJA study authors said their results showed antimicrobial stewardship initiatives should target perioperative prophylaxis.

Their suggestions included the introduction of “perioperative prophylaxis protocols with automatic stop orders at 24 hours and a requirement for evidence to support continuation of antimicrobial therapy for longer”.

The study found antimicrobial prescribing rates were highest in haematology and oncology wards, and paediatric intensive care units. However, the majority of these prescriptions were deemed appropriate — 83% and 82%, respectively.

Overall, 46% of paediatric hospital patients were prescribed at least one antimicrobial agent, of whom 31% were aged under 1 year. The most common antibiotic prescribed was gentamicin.

Associate Professor Deborah Bailey, president of the Australian and New Zealand Association of Paediatric Surgeons, defended the occasional use of antibiotics for longer than 24 hours after surgery, saying the decision to extend antibiotic use was an individualised one.

“The kinds of cases that make it into tertiary paediatric hospitals are sicker, more complex, younger patients so they may need antibiotics for longer than paediatric patients in general hospitals”, she told MJA InSight.

“The level of multiresistant infection is quite low in Australian paediatrics because general practitioners and paediatric doctors are very good at following evidence-based prescribing guidelines.”

However, Dr Treasure McGuire, of the University of Queensland’s School of Pharmacy, said other studies had raised similar concerns about antimicrobial prescribing among surgeons.

“When I’ve conducted point prevalence audits like this, you can see prescribing trends that relate as much to the prescriber as the indication”, she said. “Some surgeons appear to favour one antibiotic regimen that they always prescribe in the same way.”

Dr McGuire said cultural change was needed to improve antimicrobial stewardship in the surgical setting.

“The infectious diseases physician is less likely to pop into theatre for a chat than onto a medical ward round; and so there are fewer opportunities for upskilling, or providing feedback, to the surgical team on antimicrobial resistance and evolving antimicrobial prescribing guidelines than for other teams”, she told MJA InSight.

Dr McGuire said the appropriateness of antibiotic prescribing should be judged on a scale representing varying levels of risk.

“For instance, not prescribing enough of an antibiotic prior to surgery may be more harmful than giving slightly too much [after surgery]”, she said.

Associate Professor Madlen Gazarian, a consultant in paediatric clinical pharmacology and therapeutics and honorary associate professor in the School of Medical Sciences at the University of NSW, applauded the MJA study for providing valuable data on antibiotic prescribing patterns in Australian paediatric hospitals.

She told MJA InSight similar paediatric data also needed to be collected from general hospitals and general practice.

“Existing data collection and monitoring systems for antibiotics tend not to provide useful data routinely on issues that are different in children”, she said.

The MJA study highlighted the need for “nationally agreed paediatric antibiotic guidelines addressing common paediatric infections, commonly used antibiotics, and special issues in certain age groups, such as newborns”.

“These would provide more consistent and evidence-based guidance for clinicians and help improve the appropriateness of antibiotic prescribing for children, regardless of their location”, Professor Gazarian said.

She also agreed with the study authors that there were “ongoing gaps” between the evidence-based guidelines for surgical antibiotic prophylaxis and what is actually done in routine practice.

“This is an important public health issue which needs effective action to close those gaps”, she said, noting the large amount of surgery that is performed and the risk of increasing antibiotic resistance through inappropriate antibiotic use in such patients.

1. MJA 2014; Online 24 November
2. NAPS 2013

(Photo: Rissy Story / Shutterstock)