NIHR Signal Preventive antibiotics for gallbladder surgery not required in those at low or moderate risk

Published on 4 December 2015

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.

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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.

Citation

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].

Bibliography

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.

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.

Citation

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].

Bibliography

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.

Meta-analysis of perioperative antibiotics in patients undergoing laparoscopic cholecystectomy

Published on 4 September 2015

Pasquali, S.,Boal, M.,Griffiths, E. A.,Alderson, D.,Vohra, R. S.

Br J Surg , 2015

BACKGROUND: The effectiveness of perioperative antibiotics in reducing surgical-site infection (SSI) and overall nosocomial infections in patients undergoing laparoscopic cholecystectomy for biliary colic and low- and moderate-risk cholecystitis (Tokyo classification) is unclear. A systematic review and meta-analysis was performed to assess this. METHODS: Searches were conducted of the MEDLINE, Embase and Cochrane databases. Only randomized clinical trials (RCTs) were included. The analysis was performed using the random-effects method, and the risk ratio (RR) with 95 per cent c.i. was employed. RESULTS: Nineteen RCTs, published between 1997 and 2015, with a total of 5259 participants, of whom 2709 (51.5 per cent) were treated with antibiotics, were included. SSI and overall nosocomial infections were detected in 2.4 and 4.2 per cent respectively of patients given perioperative antibiotics, and in 3.2 and 7.2 per cent of those who received no antibiotics. Antibiotics did not significantly reduce the risk of SSI (RR 0.81, 95 per cent c.i. 0.58 to 1.13; P = 0.21) or overall nosocomial infections (RR 0.64, 0.36 to 1.14; P = 0.13). There was no significant between-study heterogeneity for SSI, but significant between-study heterogeneity in the eight studies that reported nosocomial infections. Analysis of studies considered to be high quality, grouped according to the timing of antibiotics (preoperative only or perioperative) and reporting intention-to-treat analyses, again failed to show a significant reduction in SSI. CONCLUSION: Antibiotics should not be administered before laparoscopic cholecystectomy in patients with biliary colic and/or low- and moderate-risk cholecystitis.

Expert commentary

Sometimes we need studies to give us permission to do what we have felt for a long time is the right thing to do! There are two main possible areas where antibiotics might have made a difference - infections in the gallbladder bed, which unless foreign materials have been left in are very rare indeed, or in the umbilical wound where “infections” are very common but antibiotics are not helping to prevent infections. This study has shown conclusively that we can safely discontinue giving antibiotics in straight forward cholecystectomies and will make significant savings for the health service and reduce the unnecessary usage of antibiotics.

Mr Ian Beckingham, President of Association of Upper Gastrointestinal Surgeons of Great Britain and Ireland