EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/82503
28 EW NEWS & OPINION September 2012 Pharmaceutical focus Keeping infection at bay while dipping into the high-risk cataract pool by Maxine Lipner Senior EyeWorld Contributing Writer Honing in on top regimens W hile you want to make sure that all cataract patients receive excel- lent antibiotic cover- age, certain high-risk cases require even more diligence. "Probably about 20% of our patients have some risk factor that we conventionally consider a risk factor for infection," said Eric D. Donnenfeld, M.D., co-chairman, Cornea, Nassau University Medical Center, East Meadow, N.Y. "But the biggest risk factor is one that we weren't aware of until last year, and that is age." It has come to light that the older the patient, the greater the risk of colonization by methicillin- resistant Staph aureus (MRSA). "As a matter of fact, half of the patients over age 80 will be colonized by methicillin-resistant Staph in their eyelid margin at the time of surgery, and these are patients who have no other known risk factors," Dr. Donnenfeld said. How can practitioners best protect these and other high-risk patients? EyeWorld honed in on the regimens being touted by top practi- tioners. Keeping a lid on infection Besides age, Dr. Donnenfeld pegged factors such as vitreous loss and wound leaks as increasing risk, along with patient factors such as having diabetes or having worked in a hos- pital setting. Dr. Donnenfeld keeps his guard up in all cases. "I go into cataract surgery with the expecta- tion that the patient is going to be at risk for infection, and I treat every patient that way," he said. Dr. Donnenfeld advocates closely examining the patient's lid margins pre-op since the lids are responsible for the organisms that cause endophthalmitis. "I think that the lid margins are under exam- ined," he said. If he has a patient with significant blepharitis, he will initially treat with hot compresses and omega-3 fish oil supplementa- tion. In more aggressive cases he will add an antibiotic to the mix to rub into the lid margins. "For chronic meibomian gland dysfunction (MGD), I like topical azithromycin," he said. besifloxacin is that its only use is as an eye drop so it seems the chance of a resistant organism is low." The downside of besifloxacin can be its viscosity. "It's a gooey emulsion, and that's to increase the adherence to the ocular surface," Dr. Packer said. "But it does blur vision temporarily, which is a negative for someone who just had cataract sur- gery." The post-cataract "wow fac- tor" can be impeded a bit. In higher risk cases, Dr. Packer sees this as a worthwhile tradeoff. "If you have one of these riskier cases, people understand—their expectations are quite different," he said. In a difficult case, Dr. Packer will "The biggest risk factor for post-cataract infections such as this case of endophthalmitis, caused by methicillin-resistant Staphylococcus aureus, is age," according to Dr. Donnenfeld Source: Eric D. Donnenfeld, M.D. For patients who have acute inflammation for whom he is wor- ried about MRSA, he likes to use bac- itracin ointment pre-op. In high-risk patients, to give added gram-positive coverage, he also will use bacitracin lid scrubs pre-op for a week, rubbed into the eyelid twice a day. For topi- cal therapy, he will sometimes use Polytrim (trimethoprim sulfate and polymyxin B sulfate, Allergan, Irvine, Calif.) as well, which he finds has good MRSA coverage. Betting on besifloxacin At the time of the surgery Dr. Donnenfeld will routinely prophy- lax his patients with a topical antibiotic. He currently relies on besifloxacin (Besivance, Bausch + Lomb, B+L, Rochester, N.Y.). "The reason that I like besifloxacin is that of all the fluoroquinolones, it has the most activity against methicillin- resistant Staph," Dr. Donnenfeld said. "There are no systemic ana- logues—you don't have to worry about resistance with it." In addition, he finds that the vehicle adheres to the lid margins, adding contact time there as well as to the tear surface. "It has been shown that one drop applied will achieve therapeutic doses for more than 24 hours," Dr. Donnenfeld said. "I start that 3 days pre-opera- tively, and I continue it for 10 days post-operatively because the risk of endophthalmitis has been shown to be bimodal—a few days following surgery and then, due to late wound leaks, it can occur about 9 days post- operatively." With this in mind, he continues the antibiotic topically for about 10 days. Dr. Donnenfeld augments this by using vancomycin intracamerally in all cataract cases. "That gives superlative gram-positive coverage, which is responsible for more than 90% of endophthalmitis," he said. "That combination of belt and sus- penders of besifloxacin, which gives gram-negative and good gram-posi- tive coverage, and vancomycin is the ideal antibiotic prophylaxis for cataract surgery." Likewise, Mark Packer, M.D., clinical associate professor of oph- thalmology, Casey Eye Institute, Oregon Health & Science University, Portland, likes besifloxacin for high- risk cases, and finds it has some ad- vantages over the other two latest generation fluoroquinolones, moxifloxacin (Vigamox, Alcon, Fort Worth, Texas) and gatifloxacin (Zymar, Allergan). "The greatest risk of post-operative infection is a bro- ken capsule and an extended length of time for the surgery," Dr. Packer said. "One of the reasons that I like start besifloxacin 3 days prior to surgery and then continue this for a couple of weeks after surgery. On the other hand, in routine cases, Dr. Packer will use a generic fluoro- quinolone like ofloxacin beginning 3 days before surgery and continu- ing it for a couple of weeks after. Dr. Packer also uses intracameral moxifloxacin in every case. He injects .1 cc of this diluted moxi- floxacin into the anterior chamber. "That makes so much sense to me," he said. "I feel as if I am doing the most that can be done to prevent infection." While this approach is off-label and brings with it a potential risk of toxic anterior segment syndrome (TASS), Dr. Packer said there are several studies now in peer-review literature that point to the safety of intracameral moxifloxacin, as well as the fact that it is widely used else- where. "I think that is the standard for me, even though it is off-label here in the U.S.," he said. Currently he sees the off-label status as giving practitioners some pause and creating unnecessary billing obstacles for those who embrace the approach. Dr. Donnenfeld also presses for regulatory change here to better protect high-risk patients and oth- ers. "The risk of endophthalmitis is certainly the most devastating complication of cataract surgery, and with an aging population and the lack of development of new an- tibiotics in ophthalmology because of the hurdles arbitrarily placed by the FDA, we are putting our patients continued on page 30