Decreased postoperative endophthalmitis rate after institution of intracameral antibiotics in a Northern California eye department

Purpose: To evaluate post-cataract-surgery endophthalmitis rates in relation to changing practice patterns in antibiotic administration. Setting: Kaiser Permanente, Diablo Service Area, California. Design: Ecological time-trend study. Methods: During 2007 through 2011, 3 time periods were identified based on increasing adoption of intracameral injections after phacoemulsification cataract surgery. In 2007, patients primarily received postoperative antibiotic drops without intracameral injection. During 2008 and 2009, in addition to the surgeons' usual postoperative topical drop regimen, patients received intracameral cefuroxime unless contraindicated by allergy or posterior capsule rupture (PCR). During 2010 and 2011, all patients received an intracameral injection of cefuroxime, moxifloxacin, or vancomycin while topical antibiotics were used according to surgeon preference. The rates of postoperative endophthalmitis during these 3 periods were calculated. Also evaluated separately were consecutive patients without PCR from a subgroup of 3 surgeons who used intracameral injection alone without perioperative topical antibiotics. Results: Nineteen cases of endophthalmitis occurred in 16-264 cataract surgeries. The respective rates per 1000 during the 3 time periods (2007, 2008 and 2009, 2010 and 2011) were as follows: 3.13 (95% confidence interval [CI], 1.43-5.93); 1.43 (95% CI, 0.66-2.72); 0.14 (95% CI, 0-0.78). One case of endophthalmitis was observed in 2038 patients without PCR who received intracameral injection only without topical antibiotics (rate per 1000: 0.49; 95% CI, 0.01-2.73). Conclusions: The adoption of intracameral antibiotic injection coincided with a decline in the rate of postoperative endophthalmitis, and a low infection rate was observed with intracameral injection alone. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.