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Jason Nelson, RN; Ava Bivens, RN;Antoinette Shinn, RN; Linda

Wanzer, RN; Christine Kasper, RN

Approximately 500,000 surgical siteinfections (SSIs) occur each year inthe United States.1 Health care-

acquired infections (HAIs) contribute toprolonged antimicrobial treatments,increased lengths of hospital stay, andeven death.2 The Centers for DiseaseControl and Prevention (CDC) reportsthat in 1999, the most prevalent causes ofSSIs were Staphylococcus aureus (S aureus),coagulase-negative staphylococci, entero-coccus species, and Escherichia coli (Ecoli).2,3 There have been no publishedchanges about the prevalence of thesebacteria in relation to SSIs since 1999. Astudy published in 2003 reports thatextremes of costs for SSIs may exceed$92,363 for patients with SSIs caused bymethicillin-resistant S aureus (MRSA).4

The most common source of SSIs areendogenous flora,5 but exogenous floraalso are a possible cause.2,6 If exogenousflora are causing some SSIs, how are theybeing transmitted? Could the hands ofhealth care workers be a source? Whatother surfaces might be involved viadirect or indirect contact with patients?One inanimate item in the OR that fre-quently is in contact with staff members’hands is the telephone. This articledescribes a study conducted to identifyand quantify bacterial contamination ontelephones in the OR of a large, teachingmedical center.

RESEARCH QUESTIONSThis study attempted to answer the

following research questions.1. In what quantity are bacteria present

on OR telephones? 2. Are the bacteria most frequently

involved in SSIs present on telephonesin the OR?

3. Are independent variables such assurgical service, time of day, culturelocation, number of surgical proce-dures before sampling, and tempera-ture and humidity associated withbacterial quantities on telephones?

LITERATURE REVIEWMany factors are associated with

HAIs, and a chain-of-infection modelprovides the best framework for depict-ing the relationships among these fac-tors and SSIs. According to the chain-of-infection model, a causative agent orpathogen survives within a reservoir,exits the reservoir via a mode of trans-mission, and enters a susceptible host,thereby causing disease.7 Intervention inany part of this process can stop diseasetransmission. Reservoir can be plants,animals, soil, water, and inanimate sur-faces.8 Of these, the most likely exoge-nous reservoir in the surgical setting iseither an inanimate surface or a human

Microbial Flora onOperating Room Telephones

• APPROXIMATELY 500,000 surgical site infec-tions (SSIs) occur each year in the United States.The purpose of this study was to determine if thebacteria most frequently involved in SSIs couldbe found on telephones in the OR.

• TWENTY-SIX CULTURES were taken fromtelephones in 14 ORs and two substerile rooms ata large teaching medical center.

• USING STANDARD LABORATORY proce-dures, the researchers identified coagulase-negative staphylococci in the cultures. The studyfound that telephones in the OR can serve asreservoirs for SSI-causing bacteria. AORN J 83(March 2006) 607-626.

ABSTRACT

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(ie, an animate reservoir). Both reser-voirs are capable of becoming transmis-sion agents.

INANIMATE SURFACES AS BACTERIAL RESERVOIRS.The evaluation of inanimate surfaces isbest categorized by Spaulding’s class-ification system, which classifies items ascritical, semicritical, or noncritical.9

Critical items present a significant risk ofinfection if microorganisms are presentbecause these items come in contact withsterile tissue. Semicritical items pose less

risk, even though theycome in contact withmucous membranes ornonintact skin. Noncriticalitems only come in contactwith intact skin and poselittle risk of infection.Noncritical items used inpatient care, however, canserve as a mode of second-ary transmission by pro-viding a reservoir that cancontaminate the hands ofhealth care workers.10 Thismode of transmission (ie,surface-to-hand transfer ofbacteria) is well docu-mented in the literature.11,12

ANIMATE RESERVOIRS AS TRANS-FER AGENTS. Proper handwashing is considered oneof the most important

steps in preventing infections.9 Despiteseveral studies documenting hands ascarriers of infection,13,14 hand washingcompliance has been shown to be as lowas 9% for medical intensive care unit(ICU) health care workers and 3% for car-diac surgery ICU health care workers.15

As few as 58% of anesthesiologists reportthat they wash their hands after contactwith every patient,16 and compliance withhand cleansing by postanesthesia careunit (PACU) staff members was shown tobe 12.5%.17 If proper hand hygiene is notperformed, items frequently contacted byhands could serve as reservoirs, and those

reservoirs could further serve to contami-nate hands; thereby increasing the risk ofspreading infections to patients duringhand-to-patient contact.

ENVIRONMENTAL SURFACES AS FOMITES. Al-though the importance of cleaning envi-ronmental surfaces is well recognizedas a standard of care, little research isavailable that describes the relationshipbetween the quantity of pathogenspresent on surfaces and increased HAIrates.18 Bacteria are capable of transfer-ring antibiotic resistance;19-23 therefore, itcan be argued that where bacteria areallowed to survive on environmentalsurfaces, antibiotic resistance could beincreased. It is reasonable to questionthe cleanliness of environmental sur-faces in the surgical setting, especiallywhen as much as 32% of anesthesiaequipment has been found to haveoccult blood present.24

The role of inanimate surfaces asfomites (ie, an inanimate object thatserves to transmit an infectious agentfrom person to person) is not well docu-mented. Some recent studies suggest thatthere is no link between infection ratesand surface contamination,25-27 althoughother studies demonstrate that environ-mental surfaces and nursing uniformshave increased contamination frompatients known to be infected or colo-nized with MRSA.28,29 A wide range ofenvironmental surfaces have been shownto be sources of HAI, including an elec-tronic ear probe,29 a stretcher frame,28 ashower handle,28 and OR surfaces.30

To determine the likelihood of bac-terial presence on telephones and sub-sequent transfer via hands, the litera-ture was reviewed to identify survivaltimes on hands and inanimate surfacesof the bacteria most frequently impli-cated in SSIs. These bacteria are S aureus,coagulase-negative staphylococci, ente-rococcus species, and E coli. The litera-ture review also included MRSA andvancomycin-resistant enterococci (VRE),

Critical itemsthat come intocontact withsterile tissue

present asignificant riskof infection if

microorganismsare present.

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because both of these bacteria are vari-ants of S aureus and enterococcus species.Few studies have examined bacterialgrowth on telephones; therefore, studiesusing plastic surfaces also were reviewed.

Table 1 is a compilation of the litera-ture review and is reflective of experi-mental and quasi-experimental studiesdating back to 1989. Although some ofthe studies are dated, in many cases thesestudies are either landmark or sole-

source references. Each ofthe studies used differentinoculum concentrationsand techniques and pro-vides evidence that bacte-ria might be present on ORtelephones. These studiesindicate that the passageof time alone will not elim-inate bacteria sufficiently.The importance of handwashing, aseptic tech-nique, and surface decont-amination is evident.

In one study conductedto document environmen-tal surfaces and hands ofhealth care workers asreservoirs, 26 telephoneswere cultured in an ICU,

and researchers found S aureus,Acinetobacter calcoaceticus (A calcoaceticus),and Pseudomonas species.31 In anotherstudy of noncritical items frequently incontact with the hands of hospital staffmembers, 20 telephones from the OR,ICU, PACU, and emergency department(ED) were cultured; none of the culturesresulted in the identification of gram-neg-ative bacteria.32 One group of researcherscultured 11 telephones in an ICU andidentified coagulase-negative staphylo-cocci, coagulase-positive staphylococci,gram-positive rods, and alpha-hemolyticStreptococcus.33

The literature indicates the potentialfor bacteria to be present on telephonesfor varying lengths of time and demon-

strates that frequently, there is a lack ofboth hand washing and decontaminationof environmental surfaces by hospitalstaff members. Additionally, inanimatesurfaces have been implicated in infec-tions. One study clearly linked the trans-fer of bacteria from telephones to handsand from hands to other skin surfaces. Itwas demonstrated that Micrococcusluteus can be transferred from tele-phones to hands with approximately41% efficiency and from hands tomouth at the same rate.34

METHODSThe purpose of this descriptive study

was to determine if the bacteria most fre-quently involved in SSIs could be foundon telephones in the OR of a large teach-ing medical center. This study focused ex-clusively on S aureus, coagulase-negativestaphylococci, enterococcus species, E coli,MRSA, and VRE.

SAMPLE AND SETTING. The researchersintended to take a quota-based conven-ience sample of 30 cultures from tele-phones within the ORs; however, only26 cultures were obtained from tele-phones in 14 ORs and two substerilerooms. Two control cultures and twodouble cultures also were collected.Specimen collection was divided be-tween two days that were separated by19 days to decrease the likelihood thatperioperative personnel might alterhand washing, aseptic technique, andenvironmental disinfection practicesbecause they were aware of the studyand data collection.35 This research pro-tocol was approved by the institutionalreview board of the medical center andthe Uniformed Services University ofthe Health Sciences, Bethesda, Md.

SPECIMEN COLLECTION AND ANALYSIS PROCEDURES.To ensure precision in data collection, thelaboratory officer oriented the research-ers to the medical center’s laboratory andfamiliarized them with testing suppliesand procedures. With the assistance of

One study clearlylinked the transfer of

bacteria fromtelephones to

hands and fromhands to otherskin surfaces.

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TABLE 1Bacterial Survival on Surfaces

Bacterial survival Bacterial survival timetime on hands on inanimate surfaces Type of study

Enterococcus species60 minutes on • Plastic = 68 to 90 days2 Quasi-experimentalgloved and • Telephone = 60 minutes3 Quasi-experimentalungloved hands1 • Polyvinylchloride = Quasi-experimental

1 week to 4 months4

Vancomycin-resistant enterococci60 minutes on • Counter = 58 days5 Quasi-experimentalgloved and • Telephone = 60 minutes3 Quasi-experimentalungloved hands1 • Polyvinylchloride = Quasi-experimental

1 week to 4 months4

Staphylococcus aureus (S aureus)Known to survive as • Plastic = 22 days to more Quasi-experimentalskin flora than90 days2

• Laminated plastic Quasi-experimentalsurface = 2 days6

Methicillin-resistant S aureusKnown to survive as • Plastic = 40 to 51 days2 Quasi-experimentalskin flora, particularlyin nares

Escherichia coli6 minutes • Glass = 15 minutes7 Experimental

• Polystyrene tubes = Quasi-experimental3 days8

Coagulase-negative staphylococciKnown to survive as • Plastic = 41 days to Quasi-experimentalskin flora more than 90 days2

1. R Porwancher et al, “Epidemiological study of hospital-acquired infection with vancomycin-resistantEnterococcus faecium: Possible transmission by an electronic ear-probe thermometer,” Infection Controland Hospital Epidemiology 18 (November 1997) 771-773.2. A N Neely, M P Maley, “Survival of enterococci and staphylococci on hospital fabrics and plastic,” Journalof Clinical Microbiology 38 (February 2000) 724-726.3. G A Noskin et al, “Recovery of vancomycin-resistant enterococci on fingertips and environmental surfaces,”Infection Control and Hospital Epidemiology 16 (October 1995) 577-581.4. C Wendt et al, “Survival of vancomycin-resistant and vancomycin-susceptible enterococci on dry surfaces,”Journal of Clinical Microbiology 36 (December 1998) 3734-3736.5. H F Bonilla, M J Zervos, C A Kauffman, “Long-term survival of vancomycin-resistant Enterococcus faeciumon a contaminated surface,” Infection Control and Hospital Epidemiology 17 (December 1996) 770-772.6. S I Getchell-White, L G Donowitz, D H Groschel, “The inanimate environment of an intensive care unit as apotential source of nosocomial bacteria: Evidence for long survival of Acinetobacter calcoaceticus,” InfectionControl and Hospital Epidemiology 10 (September 1989) 402-407.7. B Fryklund, K Tullus, L G Burman, “Survival on skin and surfaces of epidemic and non-epidemic strains ofenterobacteria from neonatal special care units,” The Journal of Hospital Infection 29 (March 1995) 201-228.8. S M Smith, R H Eng, F T Padberg, Jr, “Survival of nosocomial pathogenic bacteria at ambient temperature,”Journal of Medicine 27 no 5-6 (1996) 293-302.

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the microbiologist, the researchersdeveloped a guideline, depicted inFigure 1, for all testing procedures. Thisbacteria-identification algorithm wasadapted from algorithms found in TheTextbook of Diagnostic Microbiology.36 Theguideline was incorporated into a stan-dardized specimen data collection andanalysis sheet for use in recording theidentification and interpretation of bac-teria. The data collection sheet was usedto capture data related to • surgical service, • the time of day the cultures were

collected, • location of the telephone in the peri-

operative area, • surgical procedure number, and • OR temperature and humidity at the

time of sampling. The researchers’ basic laboratory

skills were evaluated during a practicalexamination using eight known bacte-rial isolates. Cultures were taken fromOR telephones at the end of surgicalprocedures and before the surgicalsuites were cleaned to eliminate unnec-essary traffic through the surgical area.

Cultures were taken in the samemanner by three researchers wearingsterile gloves. All four sides of the tele-phone hand piece handles were swab-bed. The posterior swab path includedone vertical pass from ear piece tomouth piece; the researcher held theswab on its side, rotating or rolling itacross the surface. Swabs with non-nutritive modified Stuart’s mediumwere used to obtain bacterial sampling.Validity and reliability testing wasobtained by random double-culturingand random control-culturing tech-niques. The double-culture techniqueincluded swabbing the telephones in themanner described previously with twoconsecutive culturettes, attempting toeliminate path over-run. These cul-turettes were labeled so that oneresearcher was blinded to the source.

One control culture was randomly select-ed for each culture batch. The control cul-turettes were opened and resealed with-out exposure to contaminants.

After the samples were obtained, theswabs were returned aseptically to theircases, labeled, and numbered sequential-ly. Swabs were delivered to the laborato-ry within 15 minutes of thesamples being taken. Allsamples were streaked forisolation onto trypticasesoy agar with 5% sheepblood agar, chocolate agar,and MacConkey agar,respectively. The agarplates were incubated at35º C (95º F) for 24 hours.Chocolate and blood agarplates were incubated in4% carbon dioxide (CO2)while MacConkey agarplates were incubated in1.2% CO2. After the first 24hours, all of the bacterialflora were quantifiedvisually into the numberof colonies present. If nocolonies were present at24 hours, confirmationwas performed again at48 hours.

Although blood agarplates would support thegrowth of S aureus, MRSA,coagulase-negative staph-ylococci, enterococcus species, VRE,and E coli, there was an ethical obliga-tion to rule out other bacteria capableof causing HAIs. Chocolate andMacConkey agar were used to rule outAcinetobacter species, Pseudomonas aeru-ginosa (P aeruginosa), Haemophilus in-fluenza, and Neisseria gonorrhoeae.

Staphylococcus aureus, enterococcusspecies, MRSA, VRE, coagulase-negativestaphylococci, and E coli were identifiedby shape—spherical (ie, coccus), rod-like(ie, bacillus), or spiral (ie, spirochete);

Researchers useda standardizedspecimen datacollection and

analysis sheet torecord the

identificationand

interpretation ofbacteria found

on ORtelephones.

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FIGURE 1Bacterial Identification Algorithm1-2

Negative gram stain(ie, microscope bacilli [ie,rod])

Oxidase test

Positive (ie, violet) = not Escherichia coli (E coli) Negative = possible E coli

Indole testPositive (ie, pink*)

Gram-negative identificationvia automated microbiologylaboratory testing system

E coli

Positive gram stain(ie, microscope cocci [ie, round])

Catalase test (ie, hydrogen peroxide)

Group 1 positive Group 2 negative (ie, bubbles) (ie, no bubbles) or weak positive

Staphaurex Plus test(ie, latex bound/unbound test) Phadebact D test

Coagulase positive Coagulase negative Positive = Negative =possible enterococcus not enterococcus

Staphylococcus Microdase testaureus (S aureus) Confirm via automated Brain heart infusion

microbiology laboratory with vancomycinOxacillin plate Positive Negative testing system

(ie, blue)Growth No growth Growth No growth

Not EnterococcusMethicillin- methacillin- Coagulase Vancomycin- susceptible

resistant resistant negative resistant toS aureus S aureus Micrococcus Staphylococcus Enterococcus enterococcus vancomycin

* Sample from blood agar plate/chocolate agar plate

1. H S Larsen, C R Mahon, “Staphylococci,” in The Textbook of Diagnostic Microbiology (Philadelphia: W BSaunders Co, 2000) 329-342.2. W E Kloos, J H Jorgensen, “Staphylococci,” in Manual of Clinical Microbiology, fourth ed, E H Lennetteet al, eds (Washington DC: American Society for Microbiology Press, 1985) 143-150.

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and cell wall—gram-positive or gram-negative as seen with gram stain. Spiral-shaped bacterial were not considered inthis study because they typically are notassociated with HAI. Gram-negativerods were further tested for oxidase andindole reactions. Positive oxidase andnegative indole results ruled out E coliand were tested further to rule outAcinetobacter calcoaceticus-Acinetobacterbaumannii (A calcoaceticus-baumannii) andP aeruginosa.

Gram-positive bacteria initially weretested using 3% hydrogen peroxide forcatalase testing, which was used to dif-ferentiate group 1 bacteria—catalase-positive bacteria (ie, MRSA, micrococ-cus, S aureus, coagulase-negativestaphylococci) from group 2 bacteria—catalase-negative bacteria (ie, enterococ-cus species, other streptococceae).Group 1 bacteria then were tested witha rapid latex agglutination test to rule inS aureus. Bacteria that were negative forthe rapid latex agglutination test thenwere tested with the microdase test todifferentiate coagulase-negative staph-ylococci from micrococcus species. Thehydrogen peroxide catalase-negativebacteria were analyzed using thephadebact D test to differentiate poten-tial enterococcus from other streptococ-cus species.

An automated microbiology labora-tory testing system was used for gram-positive identification and gram-negativeidentification to identify Agrobacteriumradiobacter/tumefaciens (A radiobacter/tumefaciens), A calcoaceticus-baumanniicomplex, and nine of the 43 isolates ofcoagulase-negative staphylococci. A sin-gle double-culture of coagulase-negativestaphylococci also was analyzed viagram positive identification card. Iden-tification of P aeruginosa was based on• gram-negative rod, • oxidase positive, • catalase positive, • presence of motility, and

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• growth at 42º C (107.6º F) in trypti-case soy broth.

These methods are in compliance withstandard culture techniques.37,38

Two researchers counted the coloniesindividually and took digital photo-graphs. Additionally, the surface area ofthe four vertical swab paths was calcu-lated to determine colony-forming units(CFU)/cm2. The maximum swab pathwidth was measured at 3 mm. Thelength or distance of this path wasmeasured at 95.6 cm. To find the surfacearea in cm2, length (ie, 95.6 cm) was mul-tiplied by width (ie, 0.3 cm) for a total of28.7 cm2, which is nearly equivalent tothe surface area of a repli-cate organism direct agarcontact plate with a 6-cmdiameter (ie, 3.14 x 32 =28.26 cm2). Two research-ers each entered the datainto a spreadsheet indi-vidually, using the com-pleted specimen data col-lection and analysis sheet.A test of interrater reliabil-ity revealed 100% agree-ment between the tworesearchers on all dataentered into the two sepa-rate spreadsheets.

LABORATORY AND EQUIPMENT.The laboratory used wasaccredited by the Com-mission of LaboratoryAccreditation of the College of AmericanPathologists (CAP) in 2004. The reliabili-ty and validity of the automated micro-biology laboratory testing system usedis well established among medical labo-ratories.39 Quality controls were con-ducted on all identification card lotsused in this study. Photographs weretaken using a digital camera with 2.0megapixels and five-times digital zoom.

Proficiency testing for the microbiol-ogy testing system was performed threetimes during the year of this study. At

Colonies wereidentifiedby shape

(ie, spherical,rod-like, spiral)and cell wall (ie,gram-positive,

gram-negative).

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the time of preparation of this article,test results were available for only twoof the three proficiency tests. These pro-ficiency tests showed greater than orequal to 86% accuracy of bacterial iden-tification and greater than or equal to92% performance satisfaction with 100%antigen detection. This level of testing isin accordance with CAP accreditation.40

The microbiology testing system isapproved by the US Food and Drug Ad-

ministration for bothgram-positive and gram-negative bacterial identifi-cation and sensitivity test-ing.41,42

PHENOTYPIC TESTING AGENTS.Several phenotypic testingagents were used in con-ducting this study. Noneof the agents used werebeyond their expirationdates. The same lot num-bers among agar plates,culturettes, gram-positiveand gram-negative identi-fication cards, and allother supplies were used.The only exception to thiswas the microdase test,for which lot numberschanged during the secondbatch of testing. A brief lit-erature review of the test-

ing agents is presented in Table 2 todemonstrate reliability and validity.

Staphylococcus (S) lentus, S sciuri, andS vitulus can give a false positive micro-dase reaction. The impact probably isminimal because in an evaluation ofcoagulase-negative staphylococci infec-tions, 86 cultures revealed one S sciuriand no S lentus or S vitulus.43 In onestudy, the phadebact D test was found tobe 100% effective in identifying group DStreptococcus.44 Only 80% of enterococcus,however, can be identified by group Dantigen testing.38 The catalase, Kovac’sindole, modified oxidase, and oxidase

tests are standard testing agents for theidentification of bacteria.38

STATISTICAL ANALYSIS. Data analyseswere performed using the StatisticalPackage for the Social Sciences (SPSS)version 12.0.45 Descriptive statistics (ie,frequencies, means) were used to sum-marize and describe the data variables.

RESULTSAfter the bacteria were identified

and analyzed, the results were quanti-fied. Following is a brief description ofhow the study findings relate to thethree research questions.

QUESTION ONE. In what quantity are bac-teria present on OR telephones? Themean number of colonies found on tele-phones in the sample set of this studywas 23.3 CFU or 0.81 CFU per cm2 pertelephone. The quantity of bacterianeeded to cause disease is unclear. Theonly relevant surface contaminationdata stated that floors with microbialcontamination greater than 50 coloniesper plate relate to poor cleanliness.46

This number is lower than the 23.3 CFUfound in the present study.

QUESTION TWO. Are the bacteria mostfrequently involved in SSIs present ontelephones in the OR? Of the bacteriafrequently involved in SSIs, coagulase-negative staphylococci were found tobe present on telephones in the ORwhereas S aureus, enterococcus species,and E coli were not. Figure 2 summa-rizes the types and percentages of bac-terial isolates discovered. Only the firstculture results for telephones that weredouble-cultured are included to avoidover-representation of isolates.

QUESTION THREE. Are independent vari-ables such as surgical service, time ofday, culture location, number of surgicalprocedures performed before sampling,and temperature or humidity associatedwith bacterial quantities on telephones?Based on the small sample size of thisstudy, correlations or conclusions could

The mean number of

colonies foundon telephones inthis study was23.3 colony-forming units(CFU) or 0.81CFU per cm2.

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not be drawn from the independentvariables in the study. The small sampleobtained in this study allowed fordescriptive statistical analysis only.Additionally, caution should be takenwhen drawing conclusions based on aconvenience sample from only onemedical center in which housekeepingservices are performed by the surgicaltechnologists and circulating nurses.

Table 3 summarizes the five variablesthat remained in the study after removalof the temperature and humidity vari-ables. The humidity and temperaturedata were not included because of a lack

of standardized measuring instruments.The majority of samples were collect-

ed in the morning (ie, 61.5%) versusevening (ie, 38.5%). The largest numbersof specimens were obtained from the firstsurgical procedure of the day (ie, 65.4%),followed by the second procedure (ie,30.8%), and the third procedure (ie,3.8%). The top five surgical services oper-ating in the rooms where the telephonecultures were obtained were• orthopedics (ie, 42.3%),• ophthalmology (ie, 15.4%),• general surgery (ie, 11.5%),• cardiothoracic (ie, 7.7%), and

TABLE 2Phenotype Testing Agents

Test Use Accuracy CommentRapid latex Identifies Staphylococcus aureus 94%agglutination test1,2 (S aureus)

Gram-negative Identifies gram-negative bacteria 85%identification card withautomated microbiologylaboratory testing system3

Gram-positive Identifies gram-positive bacteria 92%identification card with automated microbiology laboratory testing system4

Microdase5,6 Differentiates between 99% S lentus, S sciuri,micrococcus and coagulase- and S vitulus cannegative staphylococcus produce a false

positive result

Phadebact D7 Identifies group D Streptococcus, 100% Only 80% of including enterococcus enterococcus react

with testing agent

1. Remel Staphaurex Plus (Lenexa, Kan: Remel, Inc, 2004).2. M Wilerson et al, “Comparison of five agglutination tests for identification of Staphylococcus aureus,”Journal of Clinical Microbiology 35 (January 1997) 148-151.3. bioMerieux, Inc—Gram-negative identification+ card for in vitro diagnostic use (Rev 0402/L) (Durham,NC: bioMerieux, Inc, 2002). 4. bioMerieux, Inc—Gram-positive identification card for in vitro diagnostic use (Rev 0402/AU) (Durham,NC: bioMerieux, Inc, 2002). 5. A Faller, K H Schleifer, “Modified oxidase and bensidine tests for separation of staphylococci from micrococ-ci,” Journal of Clinical Microbiology 13 (June 1981) 1031-1035.6. J S Baker, “Comparison of various methods for differentiation of staphylococci from micrococci,” Journal ofClinical Microbiology 19 (June 1984) 875-879.7. L M Teixerira, R R Facklam, “Enterococcus,” in Manual of Clinical Microbiology, vol 1, eighth ed, P RMurray et al, eds (Washington, DC: American Society for Microbiology, 2003) 422-431.8. N M Burdash et al, “Group identification of streptococci. Evaluation of three rapid agglutination methods,”American Journal of Clinical Pathology 76 (December 1981) 819-822.

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• genitourinary surgery(ie, 7.7 %). Double cultures from

data collection days onone and two revealedcoagulase-negative staph-ylococci of similar quanti-ties, and on data collec-tion day two, testing withthe automated microbiol-ogy testing system andgram-positive identifica-tion cards revealed thesame genus and species, Sepidermidis. One telephone(ie, specimen #9910) wascultured after the roomhad been cleaned. Thisspecimen had the second highest num-ber of CFU per cm2 (ie, 2.16 CFU per cm2).

DISCUSSIONDuring this study, S aureus, entero-

coccus species, and E coli were notdetected on telephones in the OR. Theinability to find enterococcus speciesmay be related to the limitations previ-ously described for the phadebact D test.Thus, in each of the three isolates record-ed as nongroup D Streptococcus, entero-coccus may have been missed. Addi-tionally, colony counts for bacteria werelow in comparison to levels recorded forhorizontal surfaces in ORs (ie, 5.86 CFUper cm2 to 6.98 CFU per cm2),27 stetho-scopes (ie, 158 CFU),12 hospital pagers(ie, 39 CFU to 153 CFU),47 and tele-phones in the ICU (ie 7 CFU to 282CFU).33 The mean number of coloniesfound on telephones in the sample set ofthis study was 23.3 CFU or 0.81 CFU percm2 per telephone.

The only environmental surfacecontamination guidelines that werefound are based on the use of replicantorganism direct agar contact plates.The guidelines state that floors withmicrobial contamination greater than50 colonies per plate relate to poor

cleanliness.46 In this study, only foursamples exceeded that amount. Thosefour samples did not contain isolates ofAcinetobacter, Pseudomonas, or Agro-bacterium. The inability to find S aureusparallels similar difficulties in anotherstudy that were remedied by usingbroth to support environmental cul-tures, which led to increasing MRSAfindings by a factor of two.48 Similarly,one group of researchers were onlyable to isolate S aureus twice out of 114specimens.32 The inability to find E colion telephones is consistent with thatstudy, which found no gram-negativebacteria on 20 telephones in the OR,ICU, PACU, and ED.32 Additionally, theliterature review determined that E colihas a relatively short life span on envi-ronmental surfaces,49,50 which may ex-plain its absence.

The bacterium most frequently isolat-ed in this study was coagulase-negativestaphylococci. Both coagulase-negativestaphylococci and S aureus are the mostcommonly implicated bacteria in SSIs(ie, 20% and 14% respectively).2 Sub-sequently, coagulase-negative staphyl-ococci is one of the most frequently iso-lated bacteria in the laboratory.51 Thesebacteria are of little virulence52 but are

Coagulase-negativestaphylococci

Agrobacterium

Pseudomonas

Unknown

Acinetobacter

Non-group DStreptococcus

Micrococcus

3.8 %

5.8 %

1.9 %1.9 %

1.9 %1.9 %

82.8 %

Figure 2 •The percent-age ofbacteria cul-tured fromtelephones inthe OR.

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TABLE 3Variable Data Summary

Day one specimen collectionBlood Chocolate MacConkey Colony

Specimen agar agar agar forming Time Culture Procedurenumber plate plate plate Total units/cm2 Service of day location number9901 25 26 0,0 51 1.78 General AM OR 29902 5 3 0,0 8 0.28 Neurology AM Substerile 29903* 3 3 0,0 6 0.21 Plastic PM OR 19904* 6 7 0,0 13 0.45 Plastic PM OR 19905 8 6 0,0 14 0.49 General PM Substerile 29906 14 3 0,0 17 0.59 Orthopedic PM OR 19907 0,0 0,0 0,0 0 0.00 Ophthalmology AM OR 29908** 0,0 0,0 0,0 0 0.00 Not applicable

(NA) NA NA NA9909 1 1 0,0 2 0.07 Orthopedic PM OR 29910† 47 15 0,0 62 2.16 Orthopedic PM OR 19911 18 4 0,0 22 0.77 Cardiothoracic PM OR 39912 31 19 0,0 50 1.74 Ophthalmology PM OR 19913 30 13 0,0 43 1.50 Oral maxillofacial PM OR 1

Day two specimen collectionBlood Chocolate MacConkey Colony

Specimen agar agar agar forming Time Culture Procedurenumber plate plate plate Total units/cm2 Service of day location number9918 6 9 0,0 15 0.52 Orthopedic AM Substerile 19919 20 2 0,0 22 0.77 Ears, nose,

and throat AM OR 19920** 0,0 0,0 0,0 0 0.00 NA NA NA NA9921 1 0,0 0,0 1 0.03 Ophthalmology AM OR 29922 27 10 0,0 37 1.29 General AM Substerile 19923* 3 3 0,0 6 0.21 Orthopedic AM OR 19924* 5 0,0 0,0 5 0.17 Orthopedic AM OR 19925 6 0,0 0,0 6 0.21 Ophthalmology AM OR 19926 17 2 0,0 19 0.66 Orthopedic AM OR 19927 53 6 0,0 59 2.06 Orthopedic AM OR 19928 7 3 0,0 10 0.35 Genitourinary AM OR 19929 1 1 0,0 2 0.07 Genitourinary AM OR 29930 19 9 0,0 28 0.98 Orthopedic AM OR 19931 28 35 0,0 63 2.20 Orthopedic AM OR 29932 7 9 1,1 17 0.59 Orthopedic AM OR 19933 24 6 0,0 30 1.05 Cardiothoracic AM OR 19934 11 6 0,0 17 0.59 Orthopedic AM OR 1

Specimen collection was performed on two separate days separated by 19 days. Specimen numbers 9914, 9915, 9916,and 9917 were intended for collections that researchers were unable to complete on day one.

* Sequential culturing of the same telephone during the same time period.** One control culture was selected randomly for each culture batch.†Room was cleaned before swab was obtained.

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frequently implicated as the cause ofinfections in patients who are eitherimmunocompromised or have medicalimplants.53-56 A high prevalence of coagu-lase-negative staphylococci on tele-phones is consistent with a study by onegroup of researchers who isolated coag-ulase-negative staphylococci on all thetelephones that they cultured.33

INCIDENTAL FINDINGS. In a similar study,researchers found no gram-negative bac-teria.32 In the current study, there werethree gram-negative bacteria present ontelephones in the OR (ie, A calcoaceticus-baumannii complex, P aeruginosa, A radio-bacter/tumefaciens). Similarly, anothergroup of researchers also was able tofind Acinetobacter and Pseudomonas, inaddition to three isolates of S aureus from26 telephone cultures using replicantorganism direct agar contact plates.57

The use of these plates eliminate thenumber of times that bacteria are trans-ferred because they use a direct transfertechnique. Undoubtedly, some bacteriacollected from the telephones in the cur-rent study remained in the cultureswabs and were not accounted for. Hadreplicant organism direct agar contactplates been used, bacterial counts mighthave been higher.

Acinetobacter, P aeruginosa, A radiobacter/tumefaciens, and micrococcus have beenimplicated in HAIs,58-67 but these bacteriapredominantly are involved in infectionsof an immunocompromised host.38,58,59,68-70

It is likely that the transmission of thesebacteria could have been avoided withsimple hand washing, surface disinfec-tion, and use of basic aseptic techniques.

LIMITATIONSThe limitations of the study included

the following.• The gauges already present in the

surgical rooms were used to collecttemperature and humidity data.These data were removed from thestudy because no standardized

method of measurement was used.Future studies could consider usinga portable device to ensure standard-ized measurement.

• A larger sample size would help tovalidate data and provide a basis forinferential statistics.

• The bacterial colony counts found inthis study generally were low com-pared to other studies. This is largelydue to sampling technique varia-tions. Specimen collection may bemore efficient using replicant organ-ism direct agar contact impressionplates because of the advantages ofthe direct transfer technique.

• Colonies should be counted at both24 and 48 hours in an attempt to rec-ognize slow-growing bacteria. In thisstudy, morphological examinationwas conducted at 24 hours. The sep-aration of colonies based on morpho-logical examination, however, ismuch easier at 48 hours, at whichtime, hemolytic rings clearly are visi-ble and colonies have had ampletime to become differentiated.

• Although some coagulase-negativestaphylococci have been shown to bemethicillin resistant,2,71,72 in future stud-ies it may be beneficial to test for anddetermine the frequency of this resist-ance.

• Finally, adding broth to supportenvironmental cultures could lead toincreased MRSA findings.48

IMPLICATIONS AND CONCLUSIONBased on the findings of this study,

there is a need for heightened awarenessof cleaning procedures and standardprecautions. Cleaning is paramount;however, it must be performed correctlyto be effective. When bacteria are sub-jected to sublethal levels of disinfectants,they can become resistant to antibi-otics.48,63 AORN provides recommendedpractices for environmental cleaning thatincludes terminally cleaning telephones

Transmission of these bacteria could have been avoided with simple hand washing, surface disinfection, and use of

basic aseptic techniques.

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at the end of the day.18 Additionally,AORN recommends that such cleaningshould occur when equipment is visiblysoiled.73

In this study, one telephone (ie, spec-imen #9910) was cultured after the roomhad been cleaned between procedures.This specimen had the second highestnumber of colony forming units at 2.16per cm2. This finding is particularly dis-turbing and raises the question, “Shouldtelephones and other objects frequentlycontacted by staff members’ hands inthe perioperative environment becleaned between procedures rather thanonly at the end of the day?” Moreimportant, it is the initial contaminationof telephones rather than the cleaningthat is of concern. Standard precautionsrequire workers to wear gloves whenthe possibility of exposure to body flu-ids exists. On removing gloves, handsshould be washed.69 The obvious conun-drum for OR personnel is that a circulat-ing nurse frequently touches soiledmaterials and must leave the room inorder to wash his or her hands. Leavingthe room decreases the room’s positiveair pressure and places the patient atrisk for infection.18 A possible solutionmay be to provide waterless alcohol-based hand hygiene products in theindividual ORs.

Ultimately, the cleanliness of the sur-gical suite is the responsibility of peri-operative nurses.18 Perioperative man-agers in concert with facility infectioncontrol officers must ensure that USEnvironmental Protection Agency-approved hospital disinfectants areboth appropriate for emerging resistantbacteria and are being used correctly.Close attention must be applied to thesekey processes and focused to includeaseptic principles and standard precau-tions. Future research may seek to• measure hand washing compliance

in the surgical suite; • quantify the number of varying bac-

teria that can be transferred from con-taminated surfaces to incisions viagloved hands and cause infection;

• identify the frequency with whichOR personnel contact surfaces withgloved hands after performing thefunction requiring the use of thosegloves; or

• quantify the contamination of otherobjects frequently contacted byhands, such as door handles or com-puter keyboards. ❖

Jason A. Nelson, RN, BSN, CNOR,CPT, AN, USA, is an OR nurse, cur-rently serving in Mosul, Iraq.

Ava M. Bivens, RN, BSN, CNOR, MAJ,AN, USA, is a perioperative clinicalnurse specialist and performance im-provement facilitator at Walter ReedArmy Medical Center, Washington, DC.

Antoinette M. Shinn, RN, BSN,MHA, CNOR, Maj, USAF, NC, is aperioperative clinical nurse specialist atthe Keesler Medical Center, Keesler AirForce Base, Biloxi, Miss.

Linda J. Wanzer, RN, MSN, CNOR,COL, AN, USA, is a perioperative clini-cal nurse specialist and director in theGraduate School of Nursing, UniformedServices University of the HealthSciences, Bethesda, Md.

Christine E. Kasper, RN, BSN, MSC,PhD, is a professor at the UniformedServices University of the HealthSciences, Bethesda, Md, and is on thefaculty of the Department of VeteransAffairs, Office of Nursing Services.

The authors thank the Uniformed ServicesUniversity of Health Sciences, Bethesda,Md, for the grant provided for this research.They also thank Sandra C. Garmon Bibb,RN, DNSc, associate professor, GraduateSchool of Nursing, Uniformed Services

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University of the Health Sciences, Bethesda,Md, for her guidance, and microbiologistsJody Bruton, LT, USN, Naval ResearchLaboratory, Stennis Space Center, HancockCounty, Miss, and Kelly McIlwain, PhD,LT, USN, National Naval Medical Center,Bethesda, Md, for their service on theresearch committee and assistance with bac-terial identification and manuscript review.

Editor’s note: The opinions expressed inthis article are those of the authors and donot reflect the official policy or position ofthe Department of Defense or the UnitedStates Government.

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