Chlorhexidine Versus Iodine-Based Skin Preparation Was Not Associated with a Significant Difference in 90-Day Infection Risk After Instrumented Degenerative Cervical or Lumbar Spine Surgery: A Propensity Score-Matched Analysis.

Background/

Objectives

Chlorhexidine and iodine-based preparations are both widely used, and the existing literature suggests a possible advantage of chlorhexidine in clean elective surgery. Whether this extends to instrumented degenerative spine surgery is unknown. We asked whether chlorhexidine-based skin preparation reduces 90-day postoperative infection compared with iodine-based preparation after instrumented degenerative cervical or lumbar spine surgery.

Methods

A retrospective TriNetX cohort study was performed among adults undergoing instrumented degenerative cervical or lumbar spine surgery. Patients were stratified by anatomic region and by preoperative preparation exposure: chlorhexidine-based versus iodine-based. Moreover, 1:1 propensity-score matching was performed within each anatomic stratum on demographics, Charlson Comorbidity Index (CCI), diabetes, smoking, obesity and BMI, immunosuppression, methicillin-resistant Staphylococcus aureus (MRSA) carrier status, and index procedure codes. The primary outcome was 90-day postoperative infection. Secondary outcomes were superficial and deep surgical site infection, MRSA infection, incision and drainage, debridement, sepsis, urinary tract infection, and pneumonia.

Results

After matching, the cervical cohort included 3528 patients per group and the lumbar cohort 4164 per group. Postoperative infection did not differ in the cervical cohort (1.76% vs. 1.59%; risk ratio [RR] 1.11, 95% confidence interval [CI] 0.77-1.58; p = 0.578) or the lumbar cohort (3.17% vs. 3.29%; RR 0.96, 95% CI 0.76-1.22; p = 0.757). Superficial and deep infection, MRSA infection, debridement, sepsis, urinary tract infection, and pneumonia did not differ significantly in either cohort.

Conclusions

No statistically significant difference in 90-day postoperative infection was found between chlorhexidine-based and iodine-based skin preparation after instrumented degenerative cervical or lumbar spine surgery.