Abstract
Purpose::
To determine the elimination kinetics of intracameral vancomycin administered as a bolus injection at the end of phacoemulsification cataract surgery.
Methods::
Vancomycin 1mg/0.1ml saline solution was administered to 19 patients by intracameral bolus injection at the end of routine cataract surgery. The aqueous concentration of vancomycin was determined in 9 patients 1 minute after administration and in 10 patients approximately 20 hours post-operatively. Aqueous samples were obtained by inserting a Rycroft cannula into the anterior chamber via the side port incision. Fluorescence polarisation immunoassay was used to calculate the aqueous vancomycin concentration.
Results::
The median (interquartile range) vancomycin concentration was 5458 (4756 - 6389) mg/L and 40.6 (25.9 - 47.1) mg/L at 1 minute and 18 to 24 hours (median 19 hours) post-operatively, respectively. The vancomycin concentration exceeded the minimum inhibitory concentration of endophthalmitis-causing gram positive bacteria on average by a factor of between 8-10 twenty-four hours post-operatively. No adverse events or reactions were noted.
Conclusions::
The concentration of vancomycin in the anterior chamber vastly exceeds therapeutic levels for at least 24 hours following bolus intracameral injection at the end of cataract surgery.
Keywords: cataract • endophthalmitis