Evading the risk of endophthalmitis

Steps to prevent this rare but potentially catastrophic infection.

By William B. Trattler, MD and Jennifer Loh, MD

About the Author
	William Trattler, MD, is director of cornea at the Center for Excellence in Eye Care in Miami. His e-mail is wtrattler@gmail.com Disclosure: Dr. Trattler is a consultant and speaker for AMO, Allergan, Bausch + Lomb and LensAr.
	Jennifer Loh, MD, is at South Florida Eye Associates in Boca Raton. Her e-mail is jenniferlohMD@gmail.com Disclosure: Dr. Loh has no conflicts to disclose.

Though thankfully rare, endophthalmitis remains the most serious of all cataract surgery complications. Most surgeons will tell you postoperative endophthalmitis is one of their most dreaded complications with cataract surgery.

While in most cases endophthalmitis is beyond our control, the fear is a patient can suffer permanent vision loss even following a routine, uncomplicated surgery. Besides affecting visual acuity, the concern exists that a patient developing endophthalmitis can lead to a malpractice case against the surgeon.

Due to the potential devastating outcomes, physicians take many steps to prevent or reduce the risk of developing a postoperative infection. We provide a review of thoughts to consider to prevent post-operative endophthalmitis.

EVALUATING RISKS

The complicated case

One of the biggest risk factors is a complicated case — that is, any situation that substantially prolongs exposure of the anterior chamber to the environment. For instance, in cases of vitreous loss, the operative time not only increases due to the need for an anterior vitrectomy, but prolonged exposure also results in communication between the anterior and posterior chamber, which in turn means an increased risk of bacterial exposure to the vitreous cavity.

In a prolonged procedure, the surgeon can consider more aggressive treatment with postoperative antibiotics. As well, placing a suture at the corneal incision will potentially lead to better closure and may help decrease the risk of bacterial exposure in the post-operative period.

Risk of sutureless closure

Patients and surgeons love the idea of sutureless cataract surgery, but it can go seriously awry if the surgeon does not know how to create the wound properly. It is critical to understand in endophthalmitis that the most common source of bacteria is the patient’s own natural flora. Pre-existing bacteria on the conjunctival surface can enter the eye through a poorly constructed or leaky wound.

So wound construction is critical when creating a secure seal at the conclusion of the case. Taking the time to create a multi-planar incision with either a diamond or metal blade can help ensure the wound seals completely.

Alternatively, the femtosecond laser can create a tri-planar incision. In cases where the wound is not watertight, regardless of the method of construction, a suture can provide a more secure wound and reduce the risk of infection. Recently, the FDA approved a liquid hydrogel bandage, called ReSure Sealant (Ocular Therapeutix, Bedford, Mass.), for wound closure following cataract surgery. This can be an effective safeguard to ensure a sealed wound.

ISSUES WITH ANTIBIOSIS

How effective are they?

Currently, the only proven prevention for endophthalmitis is a 5% povidine iodine scrub of the lid and conjunctiva before cataract surgery.¹

Controversy surrounds the efficacy of topical antibiotics for preventing postoperative infection. While some surgeons believe perioperative topical antibiotics do not make a difference in a patient’s risk for infection, others believe they do, specifically because they reduce the bacterial load on the conjunctiva. Regardless of which camp you are in, most US surgeons prescribe topical antibiotics, if only to reduce medicolegal risk.

The medical literature supports the use of perioperative topical antibiotics in general, and initiating treatment a few days preoperatively seems to provide the best prophylaxis. In particular, studies have reported that initiating prophylactic topical antibiotics three days before cataract surgery is more effective at reducing the conjunctival bacterial load than administering drops at the time of surgery.^2,3 With reduced bacteria present on the conjunctival surface, less bacteria is available to potentially enter into the eye during the postoperative period.

While rare after cataract surgery, endopthalmitis can be a devastating complication for both the physician and patient.
COURTESY: INGRID U. SCOTT, MD, MPH

Newer-generation fluoroquinolones

Another issue with antibiotics is which to use. Bacteria have developed resistance to many of the older antibiotics, including early-generation fluoroquinolones, so many surgeons have gravitated to the newer-generation fluoroquinolones. These appear to offer the best coverage against multiple types of bacteria.

Presently Besivance (besifloxacin, Bausch + Lomb, Rochester, N.Y.), because it has no systemic equivalent, is the fluoroquinolone with the least bacterial resistance. However, Zymaxid (gatifloxacin, Allergan, Irvine, Calif.) and Vigamox/Moxeza (moxifloxacin, Alcon, Fort Worth, Texas) are also effective fluoroquinolones that provide broad antibacterial coverage.

Intracameral antibiotics

Another controversial topic is the placement of an antibiotic inside the eye during surgery. For surgeons who use antibiotics intracamerally, preservative-free Vigamox or cephalosporins are the most common choices. Evidence from Steve Arshinoff, MD, as well as the European Society of Cataract and Refractive Surgeons multicenter study, has suggested that intracameral antibiotics are effective at reducing the risk of endophthalmitis.⁴

One barrier to intracameral use of antibiotics during surgery is the expense. Some surgery centers require a new bottle of Vigamox for every patient, which can significantly increase the cost of surgery. Cephalosporins, such as cefuroxime, are less expensive than Vigamox, but a compounding pharmacy has to mix them before surgery, with the attendant risk of contamination.

Postoperative antibiotics

Because the source of the infection is usually from the conjunctival surface, reducing the conjunctival bacterial load is critical. Additionally, evidence indicates that the risk of developing a postoperative infection is not just limited to the first few days postoperatively.⁵

Many papers have reported that bacterial endophthalmitis can present beyond seven days, so many surgeons extend the use of topical antibiotics to 10 to 14 days. I continue my own patients on antibiotic drops for 10 days postoperatively.

Conclusion

Postoperative endophthalmitis is a feared complication following cataract surgery. Thankfully, surgeons can take many steps to reduce the risk that their patients will experience a postoperative infection. Hopefully, with continued efforts, the risk of endophthalmitis following cataract surgery will decrease over time. OM

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