Influence of discontinuation of prophylactic antimicrobial agent for trabeculectomy

There is no unified view of the necessity of prophylactic antimicrobial agents in trabeculectomy. Preoperative prophylactic antimicrobial agent injection and cefazolin sodium (CEZ) for trabeculectomy were discontinued at the Hiroshima University Hospital. In this study, we evaluated whether discontinuation of preoperative administration of CEZ in ophthalmology affects the incidence of postoperative infections.

We retrospectively investigated patient background, concomitant medications, subconjunctival dexamethasone sodium phosphate (DEX) injection at the end of the surgery, and the incidence of infective endophthalmitis within 6 weeks after surgery in the CEZ and non-CEZ groups. We also performed propensity score matching for background matching. Statistical analysis was performed using the Mann-Whitney U-test and Fisher's exact test.

The incidence of postoperative endophthalmitis was not significantly different between 629 and 751 patients in the CEZ and no-CEZ groups, respectively (0 in the CEZ group and 2 in the no-CEZ group, P = 0.504). More patients in the CEZ group were taking diabetes drugs preoperatively (P = 0.028) and fewer patients were receiving subconjunctival DEX at the end of surgery (P < 0.001) than those in the non-CEZ group. Propensity scores were calculated using the risk factors for postoperative infection as covariates, and matching (580 patients in the CEZ group and 580 patients in the non-CEZ group) showed no significant difference in the incidence of postoperative endophthalmitis (P = 0.500).

There was no significant difference in the incidence of endophthalmitis after trabeculectomy between the CEZ and non-CEZ groups, suggesting a decreased need for CEZ injections before trabeculectomy.