Faculty Bibliography

INTRODUCTION: Postoperative antibiotics (PA) are often administered to patients after instrumented spinal surgery until all drains are removed to prevent surgical site infections (SSI). This practice is discouraged by numerous medical society guidelines, so our institutional Neurosurgery Quality Improvement Committee decided to discontinue use of PA for this population. METHODS: We retrospectively reviewed data for patients who had instrumented spinal surgery at our institution for seven months before and after this policy change and compared the frequency of SSI and development of antibiotic related complications in patients who received PA to those who did not (non-PA). RESULTS: We identified 188 PA patients and 158 non-PA patients. Discontinuation of PA did not result in an increase in frequency of SSI (2% of PA patients vs. 0.6% of non-PA patients, p = .4). Growth of resistant bacteria was not significantly reduced in the non-PA period in comparison to the PA period (2% in the PA period and 1% in the non-PA period). The cost of antibiotics for PA patients was $5,499.62, whereas the cost of antibiotics for the non-PA patients was $0. On a per patient basis, the cost associated with antibiotics and resistant infections was significantly greater for patients who received PA than for those who did not (median of $26.32 with IQR $9.87-$46.06 vs. median of $0 with IQR $0-$0; p < .0001). CONCLUSION: After discontinuing PA for patients who had instrumented spinal procedures, we did not observe an increase in the frequency of SSI. We did, however, note that there was a non-significant decrease in the frequency of growth of resistant organisms. These findings suggest that patients in this population do not need PA, and complications can be reduced if PA are withheld.

OBJECTIVE The authors sought to determine the effects of eliminating the use of prolonged prophylactic systemic antibiotics (PPSAs) in patients with subdural and subgaleal drains. METHODS Using a retrospective database, the authors collected data for patients over the age of 17 years who had undergone cranial surgery at their institution between December 2013 and July 2014 (PPSAs period) or between December 2014 and July 2015 (non-PPSAs period) and had subdural or subgaleal drains left in place postoperatively. RESULTS One hundred five patients in the PPSAs period and 80 in the non-PPSAs period were identified. The discontinuation of PPSAs did not result in an increase in the frequency of surgical site infection (SSI). The frequency of Clostridium difficile (CDI) and the growth of resistant bacteria were reduced in the non-PPSAs period in comparison with the PPSAs period. In the 8 months after the drain prophylaxis protocol was changed, $93,194.63 were saved in the costs of antibiotics and complications related to antibiotics. CONCLUSIONS After discontinuing PPSAs for patients with subdural or subgaleal drains at their institution, the authors did not observe an increase in the frequency of SSI. They did, however, note a decrease in the frequency of CDI and the growth of resistant organisms. It appears that not only can patients in this population do without PPSAs, but also that complications are avoided when antibiotic use is limited to 24 hours after surgery.