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Full-Cycle Steam Sterilization in Ophthalmic Surgery—The Effect of Wrapping Instruments

EMMETT F. CARPEL, ALEJANDRA DECANINI MANCERA, LARÉE L. ROWAN, GERALD ENTINE, AND

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● PURPOSE: To determine if wrapping instruments inconjunction with full-cycle steam sterilization affects theincidence of postoperative infection in patients undergo-ing ophthalmic surgery in a dedicated eye center.● DESIGN: Retrospective, consecutive-case, comparativestudy.● METHODS: Two consecutive groups, each of approxi-mately 19 000 ophthalmic surgical patients, were re-viewed for postoperative infection. For both groups, thesurgical instruments were sterilized using full-cycle,steam sterilization, with a single major difference. Theinstruments for the first group were sterilized withequipment located adjacent to the operating room and nowrapping of the instruments was used, whereas for thesecond group, the sterilization equipment was located ata central facility and the instruments were wrappedbefore being transported to the operating rooms.● RESULTS: In the unwrapped sterilization group 17resumed postoperative infections were identified, com-ared to 9 presumed infections in the wrapped steriliza-ion group. Because the observed infection rates for eachroup were so low, this apparent difference is nottatistically significant (P � .16). Similarly, differences

found in the incidence of culture-positive cases of endo-phthalmitis (5 for unwrapped vs 3 for wrapped) were notstatistically significant (P � .47).● CONCLUSIONS: In a dedicated, high-volume eye facility,the incidence of presumed postoperative infection associ-ated with unwrapped and wrapped full-cycle steam steril-ization were shown to be identical within statistical error.This provides strong evidence that if eye surgical facilitiescarefully clean surgical instruments and follow the industryand manufacturer guidelines, they can, with confidence, useeither of these 2 methods of sterilization. This studypresents the first concrete data that corroborate the currentposition of The Joint Commission, American Academy ofOphthalmology (AAO) and American Society of Cataract andRefractive Surgery (ASCRS). (Am J Ophthalmol 2012;153:405–411. © 2012 by Elsevier Inc. All rights reserved.)

Accepted for publication Aug 11, 2011.From Phillips Eye Institute (E.F.C., L.L.R.), HealthPartners, Inc

(E.F.C.), and the Department of Ophthalmology, University of Minne-sota (E.F.C., A.D.M.), Minneapolis, Minnesota; Radiation MonitoringDevices, Inc (G.E.), Watertown, Massachusetts; and Statistics Depart-ment, The Wharton School, University of Pennsylvania (O.E.), Phila-delphia, Pennsylvania.

Inquiries to LaRée L. Rowan, Phillips Eye Institute, 2215 Park Ave,

Minneapolis, MN 55404; e-mail: Laree.rowan@allina.com

© 2012 BY ELSEVIER INC. A0002-9394/$36.00doi:10.1016/j.ajo.2011.08.013

A SAFE SURGICAL OUTCOME IS OF PRIMARY IMPOR-

tance in any surgical procedure and good instru-ment cleaning and sterilization techniques are

essential in this regard. While there are general standardsfor sterilization and care of instruments, sterilization tech-niques and standards have not necessarily been designedwith modern ophthalmic surgery in mind. Preparing sur-gical instruments in preparation for surgery is a complexmulti-step practice. The best assurance of a sterile productis careful execution of every step in the process coupledwith an ongoing quality control program.1,2 This includesareful cleaning and sterilization according to manufac-urer recommendations.

The most current knowledge relative to instrumentrocessing is included in the Association for the Advance-ent of Medical Instrumentation (AAMI) “Comprehen-

ive Guide to Steam Sterilization and Sterility Assurancen Health Care Facilities,” the Centers for Disease Controlnd Prevention (CDC) “Guideline for Disinfection andterilization in Healthcare Facilities, 2008,” and the As-ociation of periOperative Registered Nurses (AORN)Recommended Practices for Sterilization in the Perioper-tive Practice Setting.”3–5 The AORN recommendedractices are intended as achievable recommendationsepresenting what is believed to be an optimal level ofractice.6 However, these standards were derived from expe-

rience based on general surgery and, until now, there wereno data available specific to ophthalmology.

The most widely used and recommended method forsterilization of surgical instruments is full-cycle steamsterilization, a method commonly used in 1 of 2 variations.The first variation, referred to as wrapped, is typically donein a central location and requires that the instruments bewrapped prior to undergoing sterilization so that they canbe available for future use and be readily transportedsubstantial distances to the operating theater. This methodties up the instruments for quite some time since thematerial used to wrap the instruments may take severalhours to dry. The sterile wrapped instruments remainsterile unless the wrapping becomes compromised or untilthey are used for surgery. The second variation, referred toas unwrapped, is conducted with equipment located im-mediately adjacent to or within the operating room, whichlessens the likelihood of contamination during transport.

This method requires the immediate use of instruments. As

LL RIGHTS RESERVED. 405

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would be expected, this unwrapped variation has substan-tial economic benefits since instruments can be processedmuch more quickly, thereby dramatically reducing thenumber of instruments that must be kept in inventory.

It is important to note that the unwrapped full-cyclevariation is sometimes incorrectly called “flash steriliza-tion,” a method used to rapidly sterilize a surgical tool thathad not been sterilized or inadvertently had becomenonsterile and that is immediately and urgently needed bythe surgical team. This flash sterilization method (3 min-utes at 270 F at 27–28 pounds of pressure), which mayinvolve substantial compromises, is not a topic of thisreport. Only the full-cycle unwrapped steam sterilization,with specified ranges of time and pressure related toinstrument type, and with mechanical, chemical, andbiologic markers (Geobacillus stearothermophilus), is rele-vant. As part of any sterilization method, thorough clean-ing of all surgical instruments is also important to preventtoxic anterior segment syndrome (TASS).7–9 This studydoes not deal with TASS, which is a sterile postoperativeinflammation, but rather is confined solely to infectionsand antimicrobial sterilization.

The defining event that prompted this study was TheJoint Commission’s review of a high-volume specialty eyehospital during January 2008 that called into question theinstitution’s long-standing use of full-cycle unwrappedsteam sterilization for ophthalmic surgery. In spite of anunbroken record of excellent patient safety, no concernsabout this issue in previous Joint Commission reviews,adherence to the detailed method of full-cycle unwrappedsteam sterilization outlined by AAMI and AORN, and noevidence-based data on the efficacy of different methods ofsterilization for use in ophthalmic surgery, The JointCommission summarily ordered the facility to immediatelyconvert to full-cycle wrapped steam sterilization or facenonaccreditation. At stake also was the possibility thatother centers in the United States doing eye surgery,including specialty eye hospitals and ambulatory surgerycenters, that used full-cycle unwrapped steam sterilizationor other safe methods would be required to undergo thedisruption and huge burden of switching to the particularmethod of sterilization that, at that time, The JointCommission deemed preferable.

Subsequently, medical and administrative leadership atthe eye hospital, the American Academy of Ophthalmol-ogy (AAO), and the American Society of Cataract andRefractive Surgery (ASCRS) engaged in further discussionwith The Joint Commission regarding its position onsterilization of ophthalmic instruments. As a result, TheJoint Commission and the American Society of Cataractand Refractive Surgery published communiqués regardingThe Joint Commission’s updated position on methods ofsterilization, which focused on the processes involved in

the cleaning and sterilization of instruments.10,11

AMERICAN JOURNAL OF406

METHODS

● BACKGROUND: The facility is a dedicated eye specialtyospital. It has a medical staff of 150 physicians, 65 ofhom are active surgical staff. There is no standing staff,nlike other notable eye centers; rather, it is a center tohich ophthalmologists bring their own patients. Therere 10 operating rooms (ORs), inpatient beds, and aompounding pharmacy. Only eye procedures, from pri-ary to tertiary, are performed at the facility, and it

verages over 10 000 surgical procedures a year.The institution sponsors continuing medical education

nd training courses, and although residents and fellowsarticipate with their preceptors, there is no resident orellowship training program. Over 50% of the activeedical staff serve on a hospital committee. The Creden-

ialing/Quality Improvement, Patient Care, and Medicalxecutive committees review various quality indicators,hich include complications and infection rates.As described above, the method by which the institu-

ion used to sterilize surgical instruments, full-cycle un-rapped steam sterilization, had been in place for over 20ears, during which multiple surveys of the hospital andeview of the various components of its infection controlystem had been performed by The Joint Commission.owever, because of The Joint Commission’s position on

nwrapped sterilization, the facility converted to wrappedteam sterilization on February 21, 2008. Although switchingaused weeks of disruption to patient care and cost millions ofollars, it did present an unusual opportunity to gather somectual data about the efficacy of the 2 methods so that futureecisions could be made with a stronger scientific basis.

● COHORT AND STATISTICS: The patients were dividedinto 2 consecutive groups and data were collected for 2equal time periods, before and after the change to thewrapped method. Both groups included a time period of277 days. The first group included all patients who under-went surgery from April 5, 2006 to February 20, 2008, withwhom the unwrapped full-cycle sterilization process hadbeen used. The second group included all patients whoseprocedures took place from February 21, 2008, the day onwhich the change to the wrapped method began, throughDecember 31, 2009. It should be noted that the processesof decontamination and cleaning prior to both methods ofsterilization were identical. The manufacturer for thesteam sterilizers used in the unwrapped group was Steris/Amsco Century (V 116 Pre-Vac Steam Sterilizer; Monter-rey, Mexico). The manufacturer for steam sterilization inthe wrapped group was Getinge (Model 833HC; partsmade in Sweden, assembled in Rochester, New York,USA). Steam sterilizer recommendations were followed foreach manufacturer.

The only patients whose data were excluded from our studywere those who had received surgery at other institutions and

who were later brought to the facility for treatment of

OPHTHALMOLOGY MARCH 2012

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postoperative infections arising from activity at those otherlocations.

● INFECTION SURVEILLANCE: The focus of the reviewas to compare the rates of postoperative infections using

he wrapped and unwrapped variations of full-cycle steamterilization to determine if either resulted in substantiallyetter outcomes. All presumed postoperative infections thatccurred within 3 months after surgery were considered.hese were identified as part of the hospital’s Infectionontrol Program. The program includes surveillance, focused

tudies, outbreak investigation, isolation and control mea-ures, education, and quality improvement initiatives. Annfection Control Practitioner has responsibility for the de-artment performance, assessment, and improvement plans.

Three types of surveillance strategies are used. First, there isargeted surveillance, which includes surveillance for allurgical, diagnostic, and refractive procedures. Infection datare obtained by reviewing daily microbiology reports, patientnfection sheets from staff, and any other special reports asequested. Second, problem-oriented surveillance investigateslusters, outbreaks, or increasing infection rates. Third, therere focused studies to investigate 1 or more cases of epidemi-logic importance and new or changed procedures.

Following this, the Patient Care and Quality Improve-ent committees review all of the postoperative infection

urveillance. In addition, every 3 months, a survey request-ng the surgeon to report infections is sent to each affiliatedphthalmologist along with a list of patients who hadndergone surgery at the eye hospital. The Infectionontrol Practitioner reviews the surveys, and the results

re tabulated quarterly and brought to the committees foriscussion and, if necessary, investigation. All possiblenfections are ascribed to the date on which the surgeryook place, not when discovered.

RESULTS

DURING THE PERIOD OF THE REVIEW, THE TURNOVER OF

active staff varied from 6% to 7% annually, with nosignificant differences between the groups studied. Simi-larly, the turnover of surgeons kept relatively constant overboth periods and ranged from 4 to 6 surgeons per year. Thesurgeon response rate to the questionnaire regarding infec-tions ranged from 60% to 70%, with no significant differencesin rates from year to year. Finally, no pattern was identified inthe cases of infection that correlated to the nursing staff, aparticular surgeon, or a given operating room.

In the first group of patients, for whom the unwrappedmethod was used, the total number of surgeries was 19 008and the mean age of the patients was 68.72. In the secondgroup, for whom the wrapped method was employed, thetotal number of surgeries was 19 462 and the mean age of

the patients was 70.66 years. 5

STEAM STERILIZATION IN OVOL. 153, NO. 3

The data indicate that for the first group of patients,there were 17 presumed postoperative infections, thedistribution of which was: phacoemulsification 5, cornea 0,cosmetic 0, glaucoma 1, plastic 2, retina (nonvitrectomy)2, and vitrectomy 7 (3 25-gauge). In the second group,there were 9 presumed postoperative infections, the distri-bution of which was: phacoemulsification 4, cornea 2,cosmetic 0, plastic 1, retina (nonvitrectomy) 0, vitrectomy1, and glaucoma 1 (Table 1).

In the first (unwrapped) group, there were 12 cases ofpresumed endophthalmitis (5 having positive cultures)compared to 5 cases (3 having positive cultures) in thesecond group (Table 2). There were no clusters of infec-tions in either group.

The results show that the presumed infection rate usingunwrapped sterilization (17/19 008) was 0.09% � 0.021%,while the rate for the procedures using wrapped steriliza-tion (9/19 462) was 0.05% � 0.016%. While the presumedinfection rate differs by almost a factor of 2, each rate is sosmall that they are statistically identical. Specifically, therates are only 1.8 standard deviations apart, indicating thatone can only be 83% confident that the 2 rates aredifferent (P � .16). This is well below the standardaccepted confidence rate of 95% (P � .05). Thus, usingthe most widely accepted criteria, from a statistical per-spective, the infection rates for the 2 methods of steamsterilization are the same. Similarly, the difference inculture-positive cases (5 unwrapped and 3 wrapped) wasalso shown to be not statistically significant (P � .47).

Although not the primary focus of the study, a review ofnfection data from 1992 to 2007 (a period during whichnly the unwrapped method was employed) is included forrend analysis (Figure). This analysis shows a trend ofeneral decrease in the infection rate over a 16-yeareriod, but the year-to-year variation was substantial.It is worth mentioning that individual cases within the

TABLE 1. Comparison of Type of Procedure and InfectionIncidence for the 2 Methods of Sterilization

Procedure

Unwrapped Cases

(Infection)

Wrapped Cases

(Infection)

Phacoemulsification 11 267 (5) 10 823 (4)

Other:

Corneal 355 (0) 485 (2)

Cosmetic 184 (0) 68 (0)

Glaucoma 859 (1) 903 (1)

Miscellaneous 664 (0) 794 (0)

Plastic 1104 (2) 832 (1)

Retina (nonvitrectomy) 379 (2) 303 (0)

Retina (vitrectomy) 4197a (7) 5254b (1)

Total 19 008 (17) 19 462 (9)

a311 cases were 25-gauge.b0 cases were 25-gauge.

54-day period studied were analyzed in detail in an attempt

PHTHALMIC SURGERY 407

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to identify surgeon trends or other associated risk factors.However, the infection rate was so low that no statisticallysignificant correlation could be identified. We did, however,note that in the period reviewed with the unwrapped method,there were 311 25-gauge vitrectomies performed and 3 infec-tions (2 culture-positive), whereas in the wrapped cohort no25-gauge vitrectomies had been performed.

DISCUSSION

PREVENTION OF SURGICAL SITE INFECTION MANDATES

best practices with regard to sterilization of instrumentsand devices used in surgery. Although it may be difficult to

TABLE 2. Culture-Positive

Sex Age (Yea

Unwrapped sterilization method (n � 19 008 procedures)

M 40

F 54

F 72

M 75

M 80

Wrapped sterilization method (n � 19 142 procedures)

F 46

F 84

F 84

CE/IOL � cataract extraction with intraocular lens; CNS � coagula

vitrectomy with membrane peel.

FIGURE. Infection rate—1992 through 2007. Full-cycle unwrpostoperative period for all types of ophthalmic surgeries.

determine exactly why a patient sustains an infection, the a

AMERICAN JOURNAL OF408

risk of infection is certainly increased if an unsterileinstrument is used in surgery.1

A postoperative infection is one of the most fearedcomplications of surgeons. Many factors may influence thepossibility of acquiring an infection: the type of procedure,the wound construction, the patient’s own flora, theparticular site, the quality of the postoperative care, andthe home environment.12–16 However, it is generallygreed that a particularly critical factor is that the surgerye conducted with surgical instruments and in a surgicaleld that is microbe-free.In modern surgery, surgeons assume and take for granted

hat sterilization systems are sufficient to allow them toegin surgery with microbe-free instruments. However,

ions by Sterilization Group

Procedure Culture Results Sterilization Method

PV/MP CNS, Bacillus Unwrapped

5-gauge PPV/MP CNS Unwrapped

5-gauge PPV/MP CNS Unwrapped

PV/MP Pseudomonas Unwrapped

E/IOL Streptococcus pneumoniae Unwrapped

E/IOL CNS Wrapped

E/IOL Staphylococcus aureus Wrapped

E/IOL Enterococcus Wrapped

gative staphylococci; F � female; M � male; PPV/MP � pars plana

d steam sterilization. All presumed infections within a 3-month

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been developed and thought to be the best practices, thereis a surprising lack of clinical literature on the subject, andthere are absolutely no data that specifically addressinstrument sterilization methods for ophthalmic surgery.

From a clinical perspective, there are no reports in theliterature comparing different methods of full-cycle steamsterilization in ophthalmic procedures. A search of theliterature (PubMed) found only 1 clinical study, by Leon-ard and associates,17 in which there was any comparison of

ethods of steam sterilization. Their study did not com-are 2 variations of full-cycle steam sterilization, but ratherttempted to compare full-cycle wrapped steam steriliza-ion to flash sterilization, a method of steam sterilization inhich critical steps may be omitted and sterilization timesrastically shortened to address the shortage of instru-ents. In this paper, Leonard describes an uncontrolled

ase series study to determine if the postoperative infectionate among patients undergoing procedures in which in-truments were flash sterilized was higher than theirenchmark rate of 1%. In a general hospital setting, 100urgical procedures in which flash sterilization was usedere extracted and compared to those in which no flash

terilization took place. The diagnosis of postoperativenfections was based on surgeons’ reports and postoperativehysical examinations. They showed that in the grouphere flash sterilization was used as part of the process,

here was a 3% infection incidence.A nonprospective, noncomparative report with an n of

00 with no ophthalmology cases by itself provides no basisn which to draw any meaningful conclusions with respecto ophthalmic procedures. We thus contend that with thexception of the data reported herein, no data exist thatompare methods of full-cycle steam sterilization for use inphthalmology.It should be noted that there are no surgical site

nfection data specific to ophthalmology maintained by theational Health Safety Network (NHSN). The incidences

eported herein are “worst case,” which means that allresumed postoperative infections that occurred within 3onths after any type of ophthalmic surgery were in-

luded. Thus, the incidences are not directly comparableo reported studies of postoperative endophthalmitis afterataract surgery and should not be compared with them.ince many factors may influence a postoperative infection,ost if not all infections reported in our study are unlikely to

e related to the sterilization technique.12–14,18–20 Docu-mented transmission of pathogens associated with inadequatesterilization is exceedingly rare in the world’s literature andvirtually nonexistent in the United States in the last 25years.4

One of the most frequently referenced resources forsterilization is the Comprehensive Guide to Steam Steril-ization and Sterility Assurance in Health Care Facilities(American National Standards Institute [ANSI]/AAMI).3

The document, published in 2006, is a consolidation of 5

previous recommended practices that were reviewed, re-

STEAM STERILIZATION IN OVOL. 153, NO. 3

vised, and incorporated into the new standard. The ANSI/AAMI’s 2006 document recommended that full-cycleunwrapped steam sterilization be performed only if all ofthe following conditions are met: 1) work practices ensureproper cleaning, inspection, and arrangement of instru-ments before sterilization; 2) the physical layout of thedepartment or work area ensures direct delivery of steril-ized items to the point of use (eg, the sterilizer opens intoan area either within or directly adjacent to the procedureroom); 3) procedures are developed, followed, and auditedto ensure aseptic handling and personnel safety duringtransfer of the sterilized items from the sterilizer to thepoint of use; 4) items are needed for use immediatelyfollowing sterilization. These manufacturers’ recommenda-tions are further supported by AORN,5 which offers theseractices as an optimal level of practice, noting that eachealth facility needs to determine the degree to which theecommended practices can be implemented within theirolicies and procedures. While worded a bit differently, theecommendations are similar to the ones of ANSI/AAMI.

In June 2009, the ASCRS issued a detailed positiontatement and recommendations related to steam steriliza-ion that further supported the use of full-cycle unwrappedteam sterilization done in compliance with the manufac-urers’ recommendations.11 This was also issued on behalff the AAO. It was stated that ophthalmic surgery centersnder the purview of The Joint Commission should beamiliar with the Commission’s Position Statement onteam Sterilization as well as the CDC’s Hospital Infectionontrol Practices Advisory Committee “Guideline forisinfection and Sterilization in Healthcare Facilities.”SCRS also recommended that ophthalmologists and

acilities performing ophthalmic surgery avoid using thentiquated term “flash sterilization” to refer to the full-ycle unwrapped method since it can so readily be con-used with the abbreviated procedures associated with thether common use of that term.11

As discussed above, the eye hospital unexpectedly founditself in an ideal position to compare postoperative infec-tion rates using the 2 full-cycle steam sterilization methodsin a large number of cases with similar demographics.While our data may not have captured all possible infec-tions, the data collection methods were identical for bothgroups. One might consider that some infections were sentto other institutions for care. While this is possible, it ishighly unlikely since the facility is a tertiary center andthere is no incentive for any surgeon to deviate from his orher pattern of care.

Although the results that are being reported are from aretrospective consecutive-case comparative study, we be-lieve it accurately reflects the presumed infection rate forthe 2 periods and patient cohorts that were studied, as thepatient demographics, surgeons, surgical nursing, and tech-nical staff were the same for both groups. The study wasalso a very practical one, requiring no additional changes

in staff behavior other than required by the adoption of the

PHTHALMIC SURGERY 409

wrapped method. It also required no additional datacollection other than what the hospital had already ad-opted as its standard. In contrast, to conduct a prospectiverandomized masked control study would have been quitedifficult for both financial and logistical reasons. Further-more, such a study might have proven a greater risk to patientsafety, since randomly assigning patients to 1 of the 2 groupscould very well have been disruptive to hospital function andthereby increased the possibility of human error.

There are a number of surgeon, patient, or technicalconsiderations and their influence on infection rates thatthe review could not clearly statistically evaluate becauseof the small numbers and data on hand: operative compli-cations; use of topical, subconjunctival, or intracameralantibiotics; wound construction; and patient disease. Wemade the assumption that these would be relatively con-stant over the nearly 4-year period as patient demograph-ics, hospital, and physician staff were the same. Clearcornea incisions had been in use for years, but there was 1technical surgical change of note during the review period:25-gauge vitrectomy. During the reviewed time period thatthe unwrapped method was used there were 311 25-gaugevitrectomies with 3 infections (2 culture-positive), whereasduring the time period that the wrapped method was usedthere were no 25-gauge vitrectomy procedures. Thischange in practice pattern was likely a result of discussionsamong retinal surgeons in 2007 of problems at that timewith 25-gauge vitrectomies including a possible increase ininfection risk. If one removes infections associated with25-gauge vitrectomy from the data, it narrows the apparentdifference between the unwrapped and wrapped group, andthe culture-positive rate between the 2 groups would benearly identical (unwrapped 3/19 005, 0.02%; wrapped3/19 432, 0.02%) (Table 2).

Although the staff caring for the instruments is highlyexperienced, we were not able to determine the effects ofstaff on high alert with a new process of sterilization, northe possibility of human error with a new system. As wehave used the term “presumed” throughout the study until

a positive culture was shown, the diagnosis was based on

ization and Sterility Assurance in Health Care Facilities.

AMERICAN JOURNAL OF410

clinical symptoms, signs, and response to treatment. Withsuch a low number of possible infections in each group, itis possible that a few truly non-TASS but noninfectiousinclusions could have influenced statistical outcomes.

As described in the results section of this paper, therewas a trend toward a lower incidence of presumed infectionover a 16-year period during which the unwrapped methodhad been used, but which was accompanied by a substan-tial year-to-year variation (Figure). This type of year-to-year variation has been shown in other studies.13,21,22

Throughout this period, the eye hospital has never had anoutbreak of TASS. Tracking the infection rate goingforward will shed light on year-to-year variation using thewrapped sterilization method.

The data from the 38 470 patients (over 19 000 patientsin each cohort) clearly show that the presumed infectionrates for ophthalmic surgical patients is statistically thesame for both the wrapped and unwrapped variations offull-cycle steam sterilization (P � .16). The very largenumber of subjects and the very low infection rate com-bine to provide data that are robust and a practical answerto the question at hand. However, this should not begeneralized to nonophthalmic surgical cases.

In conclusion, this study clearly indicates that even if allpresumed infections could be attributed to the sterilizationprocess—and there is no reason to believe any were—therewas no statistically significant difference (P � .16) inefficacy between the unwrapped and wrapped methods offull-cycle steam sterilization for ophthalmic surgery. Thisstudy should allow the level of comfort for both of thesevarieties of full-cycle steam sterilization to be used inter-changeably for ophthalmic surgery, with the decision as towhich to use being totally dependent on practical factorsand not the fear of excess infection. More important, thisstudy corroborates the current positions of The Joint Com-mission, the American Academy of Ophthalmology, and theAmerican Society of Cataract and Refractive Surgery on thissubject. As The Joint Commission has now stated, “If acomplete and effective process for sterilization is used, it will

be considered an effective sterilization method.”10

THE AUTHORS INDICATE NO FUNDING SUPPORT. ALL AUTHORS HAVE COMPLETED AND SUBMITTED THE ICMJE FORM FORDisclosure of Potential Conflicts of Interest. Two of the authors (E.C., L.R.) are employed at Phillips Eye Institute outside of this study. Involved indesign (E.C., G.E., O.E.) and conduct (E.C., A.D., L.R., G.E.) of the study; collection (E.C., L.R.), management (E.C., A.D., L.R., G.E.), analysis, andinterpretation of the data (E.C., G.E., O.E.); and preparation (E.C., A.D., L.R., G.E.), review, and approval of the manuscript (E.C., A.D., L.R., G.E.,O.E.). Because this retrospective review was for purposes of quality improvement and infectious disease monitoring, the Allina Institutional ReviewBoard (IRB) waived review. The study was conducted in accordance with the tenets of the Declaration of Helsinki and all federal or state laws of theUnited States and was HIPAA compliant.

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Biosketch

Emmett F. Carpel, MD, is an Adjunct Professor at the Department of Ophthalmology, University of Minnesota and a staffophthalmologist at HealthPartners Inc. He is Medical Director and President of the Medical Staff at the Phillips EyeInstitute, Minneapolis, Minnesota. Dr. Carpel’s clinical interests are glaucoma and corneal disease. His current researchinterests include hospital culture and patient safety.

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