Postdischarge antibiotic use for prophylaxis following spinal fusion

Effects of extended oral antibiotic prophylaxis on surgical site infections after instrumented spinal fusion: a cohort study of 901 patients with a minimum follow-up of 1 year

BACKGROUND AND PURPOSE

We aimed to determine whether an extended oral antibiotic prophylaxis protocol may reduce the rate of surgical site infection (SSI) in patients undergoing instrumented spinal fusion.

PATIENTS AND METHODS

This retrospective cohort study comprise 901 consecutive patients subjected to spinal fusion between September 2011 and December 2018 with a minimum 1-year follow-up. 368 patients operated on between September 2011 and August 2014 were administered standard intravenous prophylaxis. 533 patients operated on between September 2014 and December 2018 were administered an extended protocol with 500 mg of oral cefuroxime axetil every 12 hours (clindamycin or levofloxacin in allergic individuals) until the removal of sutures. SSI was defined following the Centers for Disease Control and Prevention criteria. The association between risk factors and the incidence of SSI was evaluated by odds ratio (OR) with a multiple logistic regression model.

RESULTS

The bivariate analysis showed a statistically significant association between SSI and the type of prophylaxis used ("extended"' = 1.7% vs. "standard" = 6.2%, p= 0.001), with a lower proportion of superficial SSIs with the extended regimen (0.8% vs. 4.1%, p = 0.001). The multiple logistic regression model showed an OR = 0.25 (95% confidence interval [CI] 0.10-0.53) for extended prophylaxis and an OR = 3.5 (CI 1.3-8.1) for non-beta-lactams antibiotics.

CONCLUSION

Extended antibiotic prophylaxis seems to be associated with a reduction in the incidence of superficial SSI in instrumented spine surgery.

Lack of association of post-discharge prophylactic antibiotics with decreased risk of surgical site infection following spinal fusion

OBJECTIVES

To determine the prevalence and factors associated with post-discharge prophylactic antibiotic use after spinal fusion and whether use was associated with decreased risk of surgical site infection (SSI).

METHODS

Persons aged 10-64 years undergoing spinal fusion between 1 January 2010 and 30 June 2015 were identified in the MarketScan Commercial Database. Complicated patients and those coded for infection from 30 days before to 2 days after the surgical admission were excluded. Outpatient oral antibiotics were identified within 2 days of surgical discharge. SSI was defined using ICD-9-CM diagnosis codes within 90 days of surgery. Generalized linear models were used to determine factors associated with post-discharge prophylactic antibiotic use and with SSI.

RESULTS

The cohort included 156 446 fusion procedures, with post-discharge prophylactic antibiotics used in 9223 (5.9%) surgeries. SSIs occurred after 2557 (1.6%) procedures. Factors significantly associated with post-discharge prophylactic antibiotics included history of lymphoma, diabetes, 3-7 versus 1-2 vertebral levels fused, and non-infectious postoperative complications. In multivariable analysis, post-discharge prophylactic antibiotic use was not associated with SSI risk after spinal fusion (relative risk 0.98; 95% CI 0.84-1.14).

CONCLUSIONS

Post-discharge prophylactic oral antibiotics after spinal fusion were used more commonly in patients with major medical comorbidities, more complex surgeries and those with postoperative complications during the surgical admission. After adjusting for surgical complexity and infection risk factors, post-discharge prophylactic antibiotic use was not associated with decreased SSI risk. These results suggest that prolonged prophylactic antibiotic use should be avoided after spine surgery, given the lack of benefit and potential for harm.

Does One Week of Postoperative Antibiotic Prophylaxis Reduce the Rate of Infection After Vagus Nerve Stimulator Surgery?

OBJECTIVE

Vagus nerve stimulation (VNS) therapy is an increasingly popular treatment for medically intractable epilepsy. During a review of our cases, we noted that one of the senior authors give patients 1 week of antibiotic prophylaxis after VNS surgery while the other does not. We reviewed our experience with postoperative antibiotic prophylaxis after VNS surgery.

METHODS

We retrospectively reviewed the records of patients from January 2009 to September 2018 who had undergone surgery for VNS therapy, including generator replacement. The office and operative notes were reviewed to obtain the indications and operative details for VNS placement.

RESULTS

A total of 570 operations were reviewed, 232 of which were primary implantations and 338 were revisions. The indication was intractable epilepsy in all cases. A total of 5 infections occurred, 4 in the group with postoperative antibiotic prophylaxis and 1 in the group without. The difference was not statistically significant.

CONCLUSION

Just as with any hardware implantation, infection of the hardware can lead to significant morbidity. However, the use of postoperative oral antibiotic prophylaxis did not show benefit in reducing the infection rate.