Abstract
Purpose::
To investigate the effectiveness of a new formulation of 5% povidone iodine (PI) at reducing the levels of bacteria found in the conjunctival sac and lid margin of patients prior to cataract surgery. The new formulation is packaged in single unit doses prepared in sterile procedural packs for direct use in the operating theatre.
Methods::
Upon entry into the anaesthetic bay separate swab samples were collected from the conjunctival sac and lid margin of the operable eyes of 12 patients undergoing cataract surgery. After anaesthetic, 3 drops of PI were applied directly to the ocular surface of each patient and left in situ for 3 minutes prior to transferring the patient to theatre. In theatre, PI was used to prep the periocular region (brow, lids and cheek); PI was left in situ for 3 minutes before a swab sample was collected from the lid margin of each patient. After draping, three drops of PI were applied directly to the ocular surface; again PI was left in situ for 3 minutes before a swab sample was collected from the inferior conjunctiva. Bacterial counts were carried out on all swab samples. PI effectiveness was determined by comparing baseline bacterial counts to those attained after PI administration. Natural logarithmic transformation of the data was required before analysis of variance was performed.
Results::
Compared with baseline samples, PI application resulted in a significant 97.8% reduction in mean bacterial numbers for the lid margin (p=0.007), with counts falling from 1.3 x103cfu/ml to 30cfu/ml, and a significant 100% reduction in numbers for the conjunctiva samples, where counts fell from 1.7 x 102cfu/ml to 0 (p=0.01).
Conclusions::
Preoperative disinfection of the eye and surrounding area with the new preparation of PI, packaged in single unit doses, significantly reduced the bacterial flora present on the lid margins and conjunctival sac.
Keywords: cataract • bacterial disease • endophthalmitis