Is Prophylactic Antibiotic Therapy Needed in Thyroidectomy?

Evaluation of preoperative antibiotic prophylaxis in clean-wound general surgery procedures: a propensity score-matched cohort study at a regional hospital

BACKGROUND

The administration of antibiotic prophylaxis for clean-wound surgeries is controversial among surgeons, despite guidelines suggesting its use. This study aimed to evaluate its effectiveness in preventing surgical site infections (SSIs) in clean-wound surgeries within a regional setting with varied practices regarding prophylaxis.

MATERIALS AND METHODS

This retrospective cohort study included four types of common general surgeries performed from March 2021 to February 2023 at a tertiary regional hospital in Thailand. The surgeries included skin/subcutaneous excision, thyroidectomy, inguinal hernia repair, and breast surgeries, all of which required regional or general anesthesia. Antibiotic prophylaxis was administered at the discretion of the attending surgeons. SSI diagnosis followed standard diagnostic criteria, involving reviewing medical records and the records of the infection control unit. Infection risk factors were examined. The primary outcome comparison used inverse probability treatment weighting of propensity scores, with covariate balance evaluated.

RESULTS

Of the 501 surgeries identified, 84 were excluded, leaving 417 eligible for analysis. Among these patients, 233 received prophylactic antibiotics, for an SSI rate of 1.3%, while 184 did not receive antibiotics, for an SSI rate of 2.2%. A comparative analysis using propensity score weighting revealed no statistically significant difference in the incidence of SSI between the groups (risk ratio [95% confidence interval]: 0.54 (0.11, 2.50), p = 0.427).

CONCLUSION

In this practical setting, with the given study size, antibiotic prophylaxis in common general surgeries involving clean wounds did not significantly prevent SSIs. Routine use recommendations should be re-evaluated.

TRIAL REGISTRATION

Not applicable as this study is a retrospective cohort study and not a clinical trial.

Benefits and Risks Associated With Antibiotic Prophylaxis for Thyroid Operations

INTRODUCTION

Prophylactic antibiotics (pABX) are commonly used prior to thyroid operations despite clean case classification. The objective of this study was to assess the association of antibiotic prophylaxis with the incidence of surgical site infection (SSI) among patients undergoing thyroidectomy.

METHODS

We performed a cohort study of all adults undergoing thyroid operations at a tertiary referral center from 2010 to 2019. The primary outcome was 30-d SSI, based on diagnosis codes and/or antibiotic use and further classified based on whether wound aspiration or operative washout were required. The association between pABX and SSI was determined using propensity score matching based on patient demographics and comorbidities likely to influence SSI risk.

RESULTS

We identified 2411 patients who underwent thyroid operations, of whom 1358 (56.3%) received pABX. Patients who received pABX had a higher mean Charlson-Deyo Comorbidity Index score than patients who did not (3.6 versus 2.9). The unadjusted incidence of SSI was higher in patients who received pABX than those who did not (6.1% versus 3.4%, P < 0.001). Few patients with SSI required aspiration or operative washout (0.29% who received pABX versus 0.19% who did not). After propensity score matching, pABX use showed no association with overall 30-d SSI (odds ratio 1.38, 95% confidence interval 0.84-2.26) or SSI requiring procedural intervention (odds ratio 3.01, 95% confidence interval 0.24-158).

CONCLUSIONS

In a large cohort of patients with a high prevalence of comorbidity, use of pABX was not associated with a decreased incidence of SSI following thyroid surgery. Efforts should be made to deimplement low-value pABX use in thyroid surgery.

Effect of Antibiotic Prophylaxis on Surgical Site Infection in Thyroid and Parathyroid Surgery: A Systematic Review and Meta-Analysis

Thyroid and parathyroid surgery are considered clean procedures, with an incidence of surgical site infection (SSI) after thyroidectomy ranging from 0.09% to 2.9%. International guidelines do not recommend routine antibiotic prophylaxis (AP), while AP seems to be employed commonly in clinical practice. The purpose of this systematic review is analyzing whether the postoperative SSI rate in thyroid and parathyroid surgery is altered by the practice of AP. We searched Pubmed, Scopus, the Cochrane Library, and Web of Science (WOS) for studies comparing AP to no preoperative antibiotics up to October 2021. Data on the SSI rate was evaluated and summarized as relative risks (RR) with 95% confidence intervals (95% CI). Risk of bias of studies were assessed with standard methods. Nine studies (4 RCTs and 5 nRCTs), including 8710 participants, were eligible for quantitative analysis. A meta-analysis showed that the SSI rate was not significantly different between AP and no preoperative antibiotics (SSI rate: 0.6% in AP vs. 2.4% in control group; RR 0.69, 0.43-1.10 95% CI, p = 0.13, I2 = 0%). A sensitivity analysis and subgroup analysis on RCTs were consistent with the main findings. Evidence of low quality supports that AP in thyroid and parathyroid surgery produce similar SSI rates as to the absence of perioperative antibiotics.