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Antibiotics Not Needed After Most Sinus Surgeries, Study Reports

Key findings

  • There is little data to support prescribing prophylactic antibiotics following endoscopic sinus surgery (ESS), despite it being common practice among surgeons
  • Researchers from Mass Eye and Ear and Massachusetts General Hospital assessed the impact of antibiotics on patients following ESS
  • The researchers conducted a randomized, double-blind clinical trial that compared the effect of the antibiotic amoxicillin-clavulanate on ESS patients to that of a placebo
  • Findings from the study revealed that antibiotics did not provide any benefit when used after routine ESS and when an infection was not present during surgery

More than 250,000 sinus surgeries occur each year for treating chronic sinus infections that don’t respond to other medical treatment. In endoscopic sinus surgery (ESS), a scope and surgical tools are inserted into the nose to widen or open the normal drainage pathways that connect the sinuses to the nasal cavity. For people with chronic or recurrent infections, those openings can be too swollen for proper drainage.

It has long been debated whether antibiotics are routinely needed immediately after ESS to reduce the risk of postoperative infections, decrease swelling and optimize patient outcomes.

Researchers Stacey T. Gray, MD, and Eric H. Holbrook, MD, of Mass Eye and Ear, worked with Marlene L. Durand, MD, of Massachusetts General Hospital and Mass Eye and Ear, to perform a randomized, double-blind clinical trial that compared the effect of the antibiotic amoxicillin-clavulanate on ESS patients to that of a placebo.

The researchers found that antibiotics are not necessary for patients after most routine endoscopic sinus surgeries. Published in the International Forum of Allergy & Rhinology, findings from their study revealed that patients who underwent endoscopic sinus surgery had no differences in outcomes including symptoms and infections whether they took an antibiotic or placebo after surgery. These findings add to the growing evidence that routine use of prophylactic post-operative antibiotics does not improve outcomes post-ESS and, instead, significantly increases the rate of diarrhea.

A Randomized Trial Comparing Antibiotics and Placebo

The research team embarked on their randomized placebo-controlled trial in 2013 when they started enrolling patients at Mass Eye and Ear undergoing uncomplicated endoscopic sinus surgery. Patients without evidence of active infection during surgery were randomized to receive either a one-week regimen of an antibiotic or placebo afterwards.

A total of 77 patients (out of 134 enrolled) who met the study criteria were included in the final analysis: 37 received antibiotics and 40 did not. Patients were examined one week and six weeks after surgery.

Patients in both groups reported improvements in sinus symptoms after surgery, however there were no statistically significant differences reported in rates of infection nasal symptoms between the two groups. More than 24% of patients in the antibiotic group reported diarrhea compared to 2.5% in the placebo group. The only reported difference in outcomes was in side effects, with patients in the antibiotic group 10 times more likely to report symptoms like diarrhea.

Antibiotics Often Unnecessarily Prescribed After Sinus Surgery

Antibiotic resistance has been a long-cited concern throughout health care, especially when treating sinus infections. However, a majority of sinus surgeons surveyed in previous studies reported giving antibiotics post-operatively.

Unnecessary antibiotic prescriptions can increase health care costs and impact quality of life due to related side effects. While previous studies have looked at this issue of the utility of antibiotics after sinus surgery, there had been minimal, mixed data. The study conducted by the Mass Eye and Ear and Mass General researchers was unique for its use of several well-validated patient outcome measures in a randomized controlled trial.

“Our findings suggest that otolaryngologists can rethink the practice of routinely prescribing antibiotics after endoscopic sinus surgery,” said study co-senior author Dr. Gray, director of the Sinus Center at Mass Eye and Ear and an associate professor of Otolaryngology–Head and Neck Surgery at Harvard Medical School. “Antibiotics should still be considered when the benefits outweigh the risks, including complex surgical procedures are performed or if the patient is at greater risk for developing an infection.”

Learn more about the Department of Otolaryngology–Head and Neck Surgery at Mass Eye and Ear

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