This is a plain English summary of an original research article
Guidelines recommend that antibiotics are only prescribed before gallbladder keyhole surgery (laparoscopy) to those at increased risk of infection. However, 36% of surgeons still prescribe them.
This systematic review found that antibiotics given before removing the gall bladder by keyhole surgery for gallstone colic did not reduce the rate of surgical site infection, distant site infections or hospital-acquired infections. Though adverse effects due to the antibiotics were uncommon, inappropriate use adds to the growing problem of antimicrobial resistance.
The review findings support NICE and the Royal College of Surgeon guidelines.
Why was this study needed?
The gallbladder stores bile, a digestive fluid produced by the liver, which helps digest fatty foods. Small stones can form in the gallbladder, which can cause abdominal pain, sickness and jaundice (when the skin and whites of the eyes turn yellow). People found to have gallstones can have their gallbladder removed via keyhole surgery if the stones cause colic or other problems.
Each year in the UK around 700,000 people have keyhole gallbladder surgery, making it one of the most common operations in the NHS. Guidance recommends that preventive antibiotics are only prescribed to those at risk of infection or when they show signs of infection.
However, there is evidence that there is variability in surgeons’ prescribing decisions and that guideline recommendations are not always being followed. This systematic review of the evidence was designed to assess whether preventive antibiotic administration reduces the infection risk for people undergoing a gallbladder operation.
What did this study do?
This systematic review pooled the results of 19 randomised controlled trials (including 5,259 participants) comparing antibiotic treatment with no treatment or a placebo (dummy pill). It only included people with low or moderate risk of infection undergoing gallbladder removal via keyhole surgery for gallstone colic. This review searched across a wide range of sources for trials and analysed the effect of different factors such as the study quality and which antibiotics were administered.
The overall quality of the underlying trials was moderate. It was often unclear if researchers were kept unaware of the treatment allocation and only seven studies used intention to treat analysis. This might have introduced some bias to the results. Some studies also failed to report all the predefined outcomes.
What did it find?
- There was a non-significant difference in the number of surgical site infections amongst people receiving antibiotics (2.4%) compared with those in the control group (3.2%), based on the pooled findings of all 19 included studies (relative risk [RR] 0.81, 95% confidence interval [CI] 0.58 to 1.13).
- Eight out of 19 studies reported distant infection (such as pneumonia and urinary tract infection) rates, with their pooled results showing a non-significant difference between those receiving antibiotics (2.3%) and those in the control groups (3.7%), (RR 0.55, 95% CI 0.30 to 1.03).
- The pooled results of eight out of 19 studies showed a non-significant difference in overall nosocomial infection rate between the antibiotics group (4.2%) compared with the control group (7.2%), (RR 0.64, 95% CI 0.36 to 1.14).
- Only one trial reported adverse reactions to antibiotics (two out of 518 people, 0.4%).
What does current guidance say on this issue?
The 2008 NICE guideline on preventing and treating surgical site infections recommends that antibiotics are only given to patients where there is an increased risk of infection such as a “contaminated” wound (for example, following trauma), infected wound or where the operation involves an implant or prosthesis. Guidance for commissioners produced by the Royal College of Surgeons in 2013 states that antibiotics should only be administered in those showing signs of infection.
What are the implications?
This review provides further evidence to support guideline recommendations that only patients at increased risk should be given preventive antibiotics either before or after keyhole gallbladder surgery. An audit, carried out in 2014 by the Royal College of Surgeons, found that 36% of surgeons prescribe antibiotics to all patients before gallbladder surgery. This audit estimated that £100,000 could be saved annually in the UK if surgeons followed current guidance about antibiotic administration.
Administering antibiotics to patients who may not need them can lead to adverse reactions to the medication (which was poorly reported in trials). Such overprescribing has consequences such as antimicrobial resistance meaning that it potentially will become harder to treat even simple infections. However, the low cost-per-patient of antibiotics may lead to a cautionary approach by surgeons, especially when post-operative infection is a key measure of their performance.
People with acute gallbladder infection or where there is significant leakage of bile during the procedure may need different consideration in respect of benefits and risks of antibiotics during surgery.
Pasquali S, Boal M, Griffiths EA, et al. Meta-analysis of perioperative antibiotics in patients undergoing laparoscopic cholecystectomy. Br J Surg. 2015. [Epub ahead of print].
Graham HE, Vasireddy A, Nehra D. A national audit of antibiotic prophylaxis in elective laparoscopic cholecystectomy. Ann R Coll Surg Engl. 2014;96(5):377-80.
NICE. Surgical site infections: prevention and treatment. CG74. London: National Institute for Health and Care Excellence; 2008.
RCS. Commissioning guide: gallstone disease. London: Royal College of Surgeons of England; 2013.
SAGES. Guidelines for the Clinical Application of Laparoscopic Biliary Tract Surgery. Los Angeles (CA): Society of American Gastrointestinal and Endoscopic Surgeons;2010.
Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre