Economical sterilization plan reduces post-cataract endophthalmitis

A network of regional eye hospitals in India reported an infection rate that was comparable to international standards.

Issue: October 2009

The incidence of postoperative endophthalmitis after cataract surgery was low, even among high-risk patients, after a modified sterilization protocol was adopted in a network of regional eye hospitals in India, a study showed.

The low infection rate was comparable to that of accepted international standards, lead author R.D. Ravindran, MS, DO, said. The study was conducted at Pondicherry Hospital in India, one of five facilities in the Aravind Eye Care System, and published in the Journal of Cataract and Refractive Surgery.

“This is significant, as more than 70% of our patients are from rural areas with poor ocular and personal hygiene, anemia, varying levels of malnutrition and environmental risk factors for infection,” Dr. Ravindran told Ocular Surgery News in an e-mail interview.

The Aravind Eye Care System’s endophthalmitis rate was lower than the accepted international benchmark of 0.1%, the study said.

“From personal experience, the overall standard is satisfactory in most of the major Indian institutions and has internationally acceptable levels of low incidence of endophthalmitis,” Dr. Ravindran said. “The 0.09% reported in this article is one of the higher incidences we have experienced in Aravind Eye Care System.”

David F. Chang

OSN U.S. Edition Cataract Surgery Board Member and a co-author of the study, David F. Chang, MD, discussed the low endophthalmitis rate in light of the largely high-risk patient population.

“Aravind does the highest volume of charitable cataract surgery in the world, and to facilitate this, they have used continuous outcomes monitoring to eliminate costly OR practices that don’t have a demonstrable benefit,” Dr. Chang said. “Because cataract surgery is already a major societal economic burden in most countries, it is important to re-evaluate traditional, arbitrary practices whose effectiveness for ophthalmic surgery is unproven and may therefore be unnecessary.”

The Aravind protocol is a potential model for institutions in other economically stressed countries. Cost-effectiveness, efficiency, and high surgical volumes need not compromise safety and quality outcomes, he said.

“To achieve high volume, rapid turnover surgery, they prepare multiple patients in the same OR, use short-cycle steam sterilization and don’t change gowns, gloves, irrigation bottles and tubing between cases,” Dr. Chang said. “This study documents what the Aravind doctors have learned over the years — that these efficient and cost-effective measures do not compromise endophthalmitis rates in their cataract patients.”

Lower infection rate for phaco

The retrospective, observational study included 42,426 eyes of patients who underwent cataract surgery at the Aravind Eye Hospital in Pondicherry during a 20-month period. Investigators identified 38 cases of presumed postoperative endophthalmitis, an incidence of 0.09%. Of those 38 cases, 34 cases followed manual small-incision extracapsular cataract extraction (ECCE).

The overall rate of postoperative endophthalmitis in ECCE cases was significantly higher than in phacoemulsification cases (P = .016). The rate was 0.03% among phaco cases.

However, the difference between endophthalmitis rates for charity patients and private patients was statistically insignificant for phaco and manual ECCE. Annually, about 70% of cataract procedures are performed at little or no cost for charity patients, Dr. Ravindran and fellow authors reported.

For phaco, the endophthalmitis rate was significantly higher for procedures performed by training surgeons than for those done by full-time staff (P = .002). However, for small- and large-incision ECCE, full-time staff and training surgeons had similar endophthalmitis rates, the authors said.

“The importance of this large study is that the same aseptic protocol is followed by all surgeons at this single hospital, from the senior staff to the residents, for both private and charity patients, and for both phaco and sutureless manual ECCE procedures,” Dr. Chang said. “These low endophthalmitis rates are achieved without intracameral antibiotic and despite the fact that about 70% of the cases are charity patients in from rural eye camps receiving manual, sutureless ECCE, which is a high risk group by Western standards.”

Steam sterilization and topical antibiotics

The sterilization protocol was designed to accommodate a high volume of cataract procedures (more than 800 daily and about 180,000 annually) and enhance operating room productivity while maintaining acceptable sterility standards, Dr. Ravindran and fellow authors said.

The protocol involved use of short-cycle steam sterilization without wrapping surgical instruments, reusing irrigation solutions and tubing, rinsing of surgical gloves with antiseptic solution between cases and preparation of the next patient while the previous patient is undergoing surgery on an adjacent table. Gloves and surgical gowns were changed after 10 or more procedures.

Preoperative infection prophylaxis involved application of topical conjunctival antibiotics, preferably third-generation fluoroquinolones, for at least 1 day before surgery and routine irrigation of the nasolacrimal passage to rule out lacrimal sac obstruction and associated infection. Povidone-iodine 5% drops were administered 5 minutes before surgery and just after surgery, Dr. Ravindran and colleagues reported.

Aspects of the modified protocol that further reduced infection rates included ensuring patients do not have lid or conjunctival infections or a blocked lacrimal sac, excluding eye lashes from the surgical field by using sterile plastic drapes and continuous postoperative use of topical antibiotics. Strict supervision, regular staff meetings and a team approach to adhering to sterilization methods also helped reduce infection rates, Dr. Ravindran said.

“The government of India has published guidelines for basic standards of sterilization to be followed in community eye care programs focusing on cataract surgery,” he said. “However, the sterilization standards practiced have wide variations.”

Additional risk factors

To further minimize infective and sterile postoperative endophthalmitis, practitioners in India should regularly replace reusable cannulas, Dr. Ravindran said. Using deionized water to clean surgical instruments and for autoclaving would also minimize infection rates.

“The irrigating solutions (commercially available ringer lactate), preferably in glass bottles, should be checked for any deposits and autoclaved before their use in intraocular surgery,” he said.

Although there was no significant difference between endophthalmitis rates of private patients and charity patients for ECCE or phaco, certain risk factors remain. – by Matt Hasson

Reference:

Ravindran RD, Venkatesh R, Chang DF, Sengupta S, Gyatsho J, Talwar B. Incidence of post-cataract endophthalmitis at Aravind Eye Hospital: outcomes of more than 42,000 consecutive cases using standardized sterilization and prophylaxis protocols. J Cataract Refract Surg. 2009;35(4):629-636.

David F. Chang, MD, can be reached at 762 Altos Oaks Drive, Suite 1, Los Altos, CA 94024, U.S.A.; +1-650-948-9123; e-mail: dceye@earthlink.net.

R.D. Ravindran, MS, DO, can be reached at Aravind Eye Hospital, Cuddalore Road, Thavalakuppam, Pondicherry, India 605007; +91-413-261-9100; e-mail: rdr@pondy.aravind.org.