SURGICAL SITE INFECTION (SSI) is a challengingproblem in general surgery practice, repre-

senting the most frequent type of infection andthe third most common type of nosocomial in-fection, sometimes causing death [1–3]. The SSI rate usually is an indicator of the quality ofhealthcare practice [4]. The care of infected sur-

gical incisions creates a financial burden anddecreases the patient’s quality of life. In everycountry, reduction in the rate of SSI helps todecrease healthcare costs, a matter of utmostimportance.

Surveillance is one of the most effectivemethods of reducing the SSI rate, as an effec-

SURGICAL INFECTIONSVolume 7, Number 6, 2006© Mary Ann Liebert, Inc.

Risk Factors for and Effect of a One-Year SurveillanceProgram on Surgical Site Infection at a University

Hospital in Turkey

EKREM KAYA,1 IBRAHIM YETIM,1 ADEM DERVISOGLU,1 MUSTAFA SUNBUL,2and YUKSEL BEK3

ABSTRACT

Background: Surveillance of surgical site infection (SSI) is one of the most effective methodsfor decreasing the incidence. We determined the risk factors for SSI and the effect of a one-year surveillance program on the rate at a tertiary-care center.

Methods: The annual SSI rate before the study period was determined in a preliminarystudy. Risk factors related to SSI, the bacteria cultured from infected sites, and the effect ofsurveillance were then analyzed prospectively. Risk factors were determined by logistic re-gression analysis, and 95% confidence intervals were calculated.

Results: The incidence of SSI decreased from 12.8% before the study to 8.8% at the end ofthe surveillance period. There were 90 SSIs (8.8%) in 1,017 procedures during the study pe-riod, most of which (77; 69%) were detected during the hospital stay. The distribution of su-perficial incisional, deep incisional, and organ/space SSI was 61.1%, 33.4%, and 5.5%, re-spectively. Prolonged preoperative hospital stay (�8 days), abdominal incision, earlypreoperative hair removal, inappropriate antimicrobial prophylaxis, whole blood transfusion,famotidine treatment, repair with mesh, age �75 years, wound contamination, high Ameri-can Society of Anesthesiologists score, malnutrition, diabetes mellitus, emergency surgery,obesity, and coexistent infection proved to be independent risk factors for SSI, whereas theskin closure technique, patient sex, presence of malignancy, smoking history, and durationof operation were not.

Staphylococcus aureus and Escherichia coli were the bacteria isolated most frequently. Sixinfected patients (5.4%) died, four because of SSI. Development of SSI increased hospital ex-penses by around US$600 per patient.

Conclusion: Surveillance even for one year decreases the incidence of SSI.

Departments of 1General Surgery, 2Clinical Microbiology and Infectious Disease, and 3Biostatistics, Ondokuz MayisUniversity School of Medicine, Samsun, Turkey.

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520 KAYA ET AL.

tive infection surveillance program can reducethe incidence as much as 35–40% [5]. Althougha successful program usually necessitates sur-veillance for many years, its maximum benefithas been observed in the first year [5–7].

The particular effect of each risk factor relatedto SSI differs among hospitals and countries[1,6,8–11]. Therefore, for a surveillance programto be successful, the relative importance of thesefactors should be assessed in each healthcarecenter. In this study, we determined the risk fac-tors related to SSI in the surgical clinic of a uni-versity hospital in Turkey and investigated theeffectiveness of a one-year surveillance programto decrease the incidence of SSI.

PATIENTS AND METHODS

Surveillance protocol and patients

This study was performed in the Departmentof General Surgery at Ondokuz Mayis Univer-sity Hospital, a 60-bed tertiary-care center inSamsun, Turkey, from January 2001 to January2002. Patients who died within 48 h aftersurgery were excluded from the study.

We used polypropylene mesh in all herniarepairs. A similar fascia closure technique wasused in all abdominal operations.

The study protocol was planned by the sur-veillance team, which consisted of a surgeon,surgery residents, a trained nurse, a clinical mi-crobiology and infectious disease specialist, amicrobiology laboratory staff member, and astatistician. The SSI rate of the one-year periodprior to the year of surveillance (index year)was determined from prospective chart review.The infections were diagnosed by the expertsurgeon according to U.S. Centers for DiseaseControl and Prevention (CDC) criteria in boththe index year and the surveillance period.

Data were recorded using a form that askedfor demographics and potential risk factors as-sociated with SSI, as identified in the literature[1]. These risk factors were: Wound class,American Society of Anesthesiologists (ASA)score, admission type (elective, emergency),preoperative hospital stay, type of anesthesia(spinal or general), type and duration of the op-eration, incision type, skin closure technique

(subcutaneous suturing, intradermal closure,or simple closure without subcutaneous sutur-ing), malnutrition, obesity, diabetes mellitus,smoking history, existence of another infection,malignant disease, use of corticosteroids, inap-propriate antimicrobial prophylaxis, wholeblood transfusion, preoperative skin shaving(for male patients), use of electrocautery for in-cision, the extent of the surgeon’s experience,mesh repair, and the presence of an ostomy ordrains. The patient’s level of education andfamotidine use as an H2-receptor antagonistwere also included as potential risk factors.Malnutrition and obesity were determined using the body mass index (BMI: weight(kg)/height (m)2]. A BMI �27.5 was acceptedas obesity [12]. Hair removal was evaluated asnone, a day before, and just before surgery.

We preferred the direct observation methodfor diagnosis of infection, both in the hospitaland in the post-discharge period. All patientswere asked to observe their incisions on post-operative days 7, 14, and 30 (Fig. 1). The pa-tients who had undergone implantation ofprosthetic material such as hernia repair withmesh were followed for 12 months.

Surgical incisions were classified as clean,clean–contaminated, contaminated, or dirty [1,13]. Antimicrobial prophylaxis (AMP) was in-tended to be given according to CDC criteria.If the AMP use was not in accordance withthese criteria, it was recorded as inappropriateantimicrobial prophylaxis.

Feedback on SSI and the results of the studywere discussed by the surveillance team everythree months. The surgery team was informedof the results, and the data were used asprospective guides to improve the quality ofcare.

Diagnosis of SSI

Surgical site infection was defined andrecorded according to the CDC criteria [1] as1) surgeon’s clinical diagnosis; 2) purulent dis-charge from the incision; 3) infection signs inthe incision; and 4) positive cultures fromfluid obtained from wound drainage or per-cutaneous aspiration. The time to diagnosis,place (in hospital or after discharge), treat-ment regimen, and extent of prolongation of

SURVEILLANCE AND SSI RATE IN TURKEY 521

hospitalization were also recorded. Pus or in-fected fluid was obtained from the infection siteand cultured on 5% sheep blood and eosinmethylene blue (EMB) agar. Antibiotic sensi-

tivity tests were performed using a standard au-tomated technique (VITEK; bioMerieux, S.A.,Marcy l’Etoile, France). The cost of the each pa-tient’s care was calculated in U.S. dollars.

FIG. 1. Algorithm of wound follow-up program. SSI � surgical site infection; ST � surgical team.

522 KAYA ET AL.

Statistical analysis

Data were analyzed using SPSS software(version 10.0; SPSS Inc., Chicago, IL). A signif-icance level of �0.05 was accepted for all tests.Multinomial logistic regression models wereconstructed for multivariate analysis of the rel-ative importance of risk factors. In univariateanalysis, the association between SSI and thecost was analyzed by the Mann-Whitney U test,and the difference in the rates of SSI before andafter the study period was analyzed by the chi-square test.

RESULTS

The SSI rate during the index period was12.3% for 1,284 procedures. A total of 1,017 pro-cedures in 583 male and 434 female patientswere followed in the year of surveillance. There

were 90 SSIs (8.8% of all procedures), whereasthe SSI rate was 4.3% according to hospital in-fection control committee (HICC) data. The dif-ference between the SSI rates in the two peri-ods was significant (p � 0.008; chi-square test).Primary blood stream infection was the secondmost common nosocomial infection (2.48%),among patients with SSI, whereas urinary tractinfection (UTI) was the third most common(1.1%). Among all hospital admissions, SSI wasthe third most common nosocomial infectionfollowing primary blood stream infection andUTI.

Patients’ education, skin closure technique,use of electrocautery or drains, type of anesthe-sia, patient sex, steroid treatment, malignancy,smoking, and duration of the operation were notrisk factors for SSI. The SSI rate was 18.4% aftermesh repairs. It was 26.8% after emergencysurgery (25 of 93 patients) and 14% after electivemesh repair. All incisional hernias repaired with

TABLE 1. PATIENT-RELATED RISK FACTORS AND SSI RATE

Risk factor N SSI rate (%) Adjusted OR (CI95) P value

Age, years�44a 484 06 0145–64 301 09.6 01.6 (0.9, 2.7) 0.0865–74 129 12.4 02.1 (1.1, 4.0) 0.02�75 103 14.6 02.6 (1.3, 4.9) 0.005

Wound classCleana 320 03.4 01Clean-contaminated 454 09.2 02.8 (1.5, 5.9) 0.009Contaminated 174 09.7 03 (1.2, 6.2) 0.001Dirty 069 27.5 10.7 (4.7, 23.0) 0.0006

ASA score1a 300 05 012 564 09.2 01.9 (1.0, 3.5) 0.033 127 15.7 03.5 (1.7, 7.0) 0.00044 026 11.5 02.4 (0.6, 9.0) 0.175

MalnutritionNoa 820 06.6 01Yes 197 18.3 03.2 (2.0, 5.0) 0.0001

Diabetes mellitusNoa 884 07.5 01Yes 133 18 02.7 (1.6, 4.5) 0.001

Admission typeElectivea 645 05.3 01Emergency 372 15.1 03.2 (2.0, 5.0) 0.0004

ObesityNoa 609 03.1 01Yes 408 17.4 06.5 (4.0, 11.0) 0.0002

Coexistent infectionAbsenta 763 05.4 01Present 254 19.3 04.2 (2.7, 6.5) 0.0002

aReference standard.OR � odds ratio; CI95 � 95% confidence interval; ASA � American Society of Anesthesiologists; SSI � surgical

site infection.

SURVEILLANCE AND SSI RATE IN TURKEY 523

mesh under emergency conditions (18 patients)developed SSI. Famotidine use was an indepen-dent risk factor for SSI. Coexistent infections (bil-iary, urinary, respiratory infections; sepsis) werethe other risk factors (Tables 1 and 2).

Seventy-seven of the SSIs (85.6%) were de-tected during hospitalization. Most of the SSIs(47; 52%) developed within 3–7 days postoper-atively, 34 (37%) on days 8–14, and 9 (11%)more than 14 days after surgery. The distribu-tion of SSIs was 55 superficial incisional(61.1%), 30 deep incisional (33.4%), and 5 or-gan/space infections (5.5%). Forty-six SSIswere treated with wound drainage only, 31with antibiotics and open wound drainage, and

13 with systemic antibiotics only. Six patientsdied of nosocomial infections, four of themfrom SSI (three organ/space and one deep in-cisional infection). Staphylococcus aureus and Es-cherichia coli were the organisms isolated mostcommonly from SSI sites (Table 3).

There was a significant correlation betweenSSI and hospital costs. The mean costs with andwithout SSI were US$1,611 � 100 and $1,007 �19, respectively (p � 0.0006; Mann-Whitney Utest). The mean prolongation of hospitalizationrelated to SSI was approximately eight days,the stays being 18.3 � 1.4 days for patients hav-ing SSI and 9.4 � 0.1 days for those who didnot (p � 0.002; Mann-Whitney U test).

TABLE 2. OTHER RISK FACTORS RELATED TO SSI RATE

Risk factor No. SSI rate (%) Adjusted OR (CI95) p value

Preoperative hospital days0a 144 07.6 011–2 475 07.6 013–7 338 06.8 00.8�8 60 33.6 10.7 (2.6, 13.6) 0.0001

Incision siteNeck or breasta 174 000.06 01Laparoscopy 105 02.3 04 (0.9, 7.5) 0.2Inguinal 132 04.8 08.7 (0.4, 39) 0.05Abdominal 606 13.4 26.7 (3.6, 193) 0.001

Operative procedureBreast or thyroida 174 000.06 01Hepatobiliary 308 09.1 17.3 (2.3, 128) 0.005Genitourinary 183 10.4 20.0 (2.6, 151) 0.004Colorectal 198 08.6 16.2 (2.1, 123) 0.007Hernia repair 154 16.0 33.5 (4.4, 250) 0.001

Hair removalNonea 239 05.1 01Just before the incision 162 07.1 01.2 (0.5, 2.7) 0.01One day before 182 14.8 02.8 (1.4, 5.5) 0.04

Inappropriate antimicrobial prophylaxisNoa 721 02.7 01Yes 276 25.4 02.5 (7.2, 20) 0.0004

Blood transfusionNoa 929 07.1 01Yes 88 27.3 04.9 (2.8, 8.3) 0.0004

Mesh useNoa 740 05.3 01Yes 277 18.4 04 (2.6, 6.3) 0.0006

Famotidine useNoa 575 07.1 01Yes 442 11.0 01.6 (1.0, 2.5) 0.03

Surgeon’s experienceSenior residenta 479 06.3 01Junior resident 167 06.6 01.05 (0.5, 2.0) 0.8Consultant 371 13.2 02.2 (1.4, 3.6) 0.001

aReference standard.OR � odds ratio; CI95 � 95% confidence interval; SSI � surgical site infection.

524 KAYA ET AL.

DISCUSSION

Despite efforts to decrease the incidence ofSSI to a satisfactory range, such infections stillare an important problem in surgical practice[1,14–16]. Various surveillance methods havebeen described in the literature. It has been ac-cepted that direct observation of the surgicalsite is the most accurate method to detect SSI[1,5,7,8]. The rates of SSI determined by directobservation and HICC reports, which are basedon laboratory data, were significantly different:8.8% vs. 4.3%, respectively, in this study. There-fore, determination of the SSI rate by labora-tory review alone is not reliable.

The rate of SSI determined by direct obser-vation decreased from 12.3% to 8.8% withinone year of the beginning of our surveillanceprogram. In other series also, the maximum de-crease in the rate of SSI has been observedwithin the first year of surveillance [5,6].

The distribution of SSI types in our study isslightly different from that in the literature.Particularly, organ/space SSIs were less com-mon than in previous reports [17,18]. This maybe attributable to the small patient volume andthe high overall infection rate. There were fourdeaths related to SSI, of which three were or-gan/space infections.

We found the independent risk factors re-lated to SSIs to be advanced age, wound con-

tamination, preoperative hospitalization formore than eight days, abdominal incision, highASA score, whole blood transfusion, and pres-ence of coexistent infection, as demonstratedclearly in the past [6,9,16,17–22]. The confi-dence intervals of the odds ratios were quitewide, similar to those in the literature. Coexis-tent infection and primary blood stream infec-tion were common in our study because thehospital is a tertiary-care center, and many pa-tients were referred from other hospitals underemergency conditions. Mesh repair was per-formed in all of our hernia cases, and this wasfound to be a risk factor for SSI. The high rateof SSI in our study can be explained by the highratio of referred acute hernia cases [23–26].These factors possibly affected the rate of SSIin hernia surgery (especially in incisional her-nia). As seen in several studies [27–29], obesitywas another independent risk factor for SSI.

Inappropriate choice and timing of pro-phylactic antibiotic continues to be an impor-tant risk factor for SSI [1,10,30,31]. Inappro-priate antibiotic use was observed in 276 of1,017 patients in this study. Control of the an-tibiotic prophylaxis regime, which is a mainpart of the surveillance program, must be em-phasized in every hospital practice. Unfortu-nately, inappropriate prophylaxis is still animportant problem in our country [32], as itis elsewhere.

TABLE 3. BACTERIA CULTURED FROM SSI

Type of operation

Breast or UpperThyroid GI HPB Colorectal Hernia Total (%)

Staphylococcus aureus 1 3 6 3 5 18 (20.0)Escherichia coli — 6 6 2 2 16 (17.8)Klebsiella pneumoniae — 2 4 1 1 8 ( 8.9)Pseudomonas aeruginosa — 2 3 3 — 8 ( 8.9)Enterococcus spp. — 2 3 1 — 6 ( 6.6)CNS — 1 1 — 2 4 ( 4.4)Klebsiella oxytoca — 1 1 2 — 4 ( 4.4)Acinetobacter baumanii — — 1 2 — 3 ( 3.3)Morganella morganii — — 1 1 — 2 ( 2.2)Proteus mirabilis — — 1 1 — 2 ( 2.2)Candida spp. — 1 — 1 — 2 ( 2.2)Culture negative 1 1 1 1 12 16 (17.8)

GI � gastrointestinal; HPB � hepatobiliary; CNS � coagulase-negative staphylococci;SSI � surgical site infection.

SURVEILLANCE AND SSI RATE IN TURKEY 525

The importance of diabetes mellitus as a riskfactor for SSI is still controversial [3,33]. Dia-betes was found to be an independent risk fac-tor for SSI in the present study. At the sametime, other risk factors were present, as mostof the diabetic patients were admitted with un-controlled blood glucose and in poor generalcondition and often required urgent surgery.

Hair removal (especially one day before theoperation) was another independent risk fac-tor. Similar results have been reported in an-other study [34], whereas Bekar et al. foundthat even cranial surgery without hair removaldid not increase the SSI rate [35]. In the presentstudy, less important risk factors for SSI werethe surgeon’s experience and famotidine use.Surprisingly, the rate of SSI was higher in op-erations performed by consultant surgeonsthan in those performed by residents. Platelland Hall reported similar results in their re-view, and explained it by the more complicatedpatient population treated by consultant sur-geons [10]. We cannot offer any definitive ex-planation of why and how famotidine admin-istration increases the rate of SSI, but gastriccolonization as a result of hypochlorhydria [36]may be responsible, particularly in patients un-dergoing abdominal surgery.

There were 16 culture-negative cases amongthe 90 SSIs. Positive wound culture is not aprerequisite for diagnosing a SSI according tothe CDC criteria [1,4]. Some of these culture-negative infections may be attributable toanaerobic bacteria. Staphylococcus aureus andE. coli were the organisms isolated most com-monly from SSIs, as in other studies [5,6,37].Other bacteria isolated were Klebsiella pneu-moniae, Pseudomonas aeruginosa, Enterococcusspp., and coagulase-negative staphylococci.Recently, it has been reported that the relativeincidence of these bacteria in SSIs has been in-creasing, especially in gastrointestinal surgery[38]. Another microorganism, Candida spp.,causes a similar course in immunocompro-mised patients [17,39]. Candida was isolatedfrom two infected patients (2.2%) in our se-ries. In conclusion, despite the small patientvolume and a short surveillance period, thisstudy has shown the effectiveness of a one-year surveillance program in reducing SSI.

REFERENCES

1. Mangram AJ, Horan TC, Pearson ML, et al. Guidelinefor prevention of surgical site infection, 1999. InfectControl Hosp Epidemiol 1999;20:247–278.

2. Martone WJ, Nichols RL. Recognition, prevention,surveillance and management of surgical site infec-tions: Introduction to the problem and symposiumoverview. Clin Infect Dis 2001;33(suppl 2):S67–S69.

3. Smith RL, Bohl JK, McElearney ST, et al. Wound in-fection after elective colorectal resection. Ann Surg2004;239:607.

4. Bruce J, Russel EM, Mallison J, Krukowski ZH. Thequality of measurement of surgical wound infectionas the basis for monitoring: A systematic review. JHosp Infect 2001;49:99–108.

5. Olson MM, Lee JT. Continuous, 10-year wound in-fection surveillance. Arch Surg 1990;125:794–802.

6. Geubbels ELPE, Groot AJM, van den Berg JM, de BoerA. An operating surveillance system of surgical siteinfections in the Netherlands: Results of the PREZIESNational Surveillance Network. Infect Control HospEpidemiol 2000;21:311–318.

7. Haley RW. The scientific basis for using surveillanceand risk factor data to reduce nosocomial infectionrates. J Hosp Infect 1995;30(Suppl 1):S3–S14.

8. Smyth ETM, Emmerson HM. Surgical site infectionsurveillance. J Hosp Infect 2000;45:173–184.

9. deBoer AS, Groot AJM, Saverijnen AJ, et al. Risk as-sessment for surgical-site infections in orthopedic patients. Infect Control Hosp Epidemiol 1999;20:402–407.

10. Platell C, Hall JC. The prevention of wound infectionin patients undergoing colorectal surgery. J Hosp In-fect 2001;49:233–238.

11. Nichols RL. Prevention surgical site infections: A sur-geon’s experience. Emerg Infect Dis 2001;7:220–224.

12. Shopbell JM, Hopkins B, Shronts EP. Nutrition screen-ing and assessment. In: Gottschich MM, ed. The Science and Practice of Nutrition Support: A Case-based Care Curriculum. Dubuque, Iowa. Kendal/Hunt Publishing, 2001:107–140.

13. Simmons BP. Guideline for prevention of surgicalwound infection. Infect Control Hosp 1982;3:185–196.

14. Leaper D. Nosocomial infection. Br J Surg 2004;91:526–527.

15. Haley RW, Culver DH, White JW, et al. The efficacyof infection surveillance and control programs in pre-venting nosocomial infections in US hospitals. Am JEpidemiol 1985;121:182–205.

16. Arias CA, Quinteno G, Vancgas BE, et al. Surveillanceof surgical site infections: Decade of experience at aColombian tertiary care center. World J Surg 2003;27:529–523.

17. Lecuona M, Torres-Lana A, Delgado-Rodriguez M,et al. Risk factors for surgical site infections diag-nosed after hospital discharge. J Hosp Infect1998;39:71–74.

526 KAYA ET AL.

18. Gaynes RP, Culver DH, Horan TC, et al. Nationalnosocomial infections surveillance system: Surgicalsite infection (SSI) rates in the United States, 1992–1998: The National Nosocomial Infections Surveil-lance System basic SSI risk index. Clin Infect Dis2001;33(suppl 2):S69–S76.

19. Cruse PJE, Foord R. A five-year prospective study of23,649 surgical wounds. Arch Surg 1973;107:206–210.

20. Hill GE, Frawley WH, Griffith KE, et al. Allogenic bloodtransfusion increases the risk of postoperative bacterialinfection: A meta–analysis. J Trauma 2003;54:908–914.

21. Haley RW, Culver DH, Morgan WM, et al. Identify-ing patients at high risk of surgical wound infection:A simple multivariate index of patient susceptibilityand wound contamination. Am J Epidemiol 1985;121:206–215.

22. Simchen E, Rozin R, Wax Y. The Israeli study of sur-gical infection of drains and the risk wound infectionin operations for hernia. Surg Gynecol Obstet 1990;170:331–337.

23. Santos KRN, Neto GBP, Fonseca LS, Filho PPG. In-cidence surveillance of wound infection in herniasurgery during hospitalization and after dischargein a university hospital. J Hosp Infect 1997;36:229–233.

24. Luijendijk RW, Hop WC J, van den Jol MP, et al. Acomparison of suture repair with mesh repair for in-cisional hernia. N Engl J Med 2000;343:392–398.

25. Koronkow M, Sauerland S, Arnt L, et al. Randomizedclinical trial of suture repair, polypropylene mesh orautodermal hernioplasty for incisional hernia. Br JSurg 2002;89:50–56.

26. Heniford BT, Park A, Ramshaw BJ, Voeller G. La-paroscopic ventral and incisional hernia repair in 407patients. J Am Coll Surg 2000;190:645–650.

27. Gottrup F. Oxygen, wound healing and the develop-ment of infection: Present status. Eur J Surg 2002;168:260–263.

28. Kaban B, Nagele A, Reddy D, et al. Obesity decreasesperioperative tissue oxygenation. Anesthesiology2004;100:274–280.

29. Choban PS, Heckler R, Burge JC, Flancbaum L. In-creased incidence of nosocomial infections in obesesurgical patients. Am Surg 1995;61:1001–1005.

30. Nichols RL, Florman S. Clinical presentation of soft-tissue infection and surgical site infections. Clin In-fect Dis 2001;33(Supp 2):S89–S92.

31. Classen DC, Evans RS, Pestotnik SL, et al. The timingof prophylactic administration of antibiotic and therisk of surgical-wound infection. N Engl J Med1992;326:281–286.

32. Hosoglu S, Sunbul M, Erol S, et al. A national surveyof surgical antibiotic prophylaxis in Turkey. InfectControl Hosp Epidemiol 2003;24:758–761.

33. McMurry JF. Wound healing with diabetes mellitus.Surg Clin North Am 1984;64:769–777.

34. Ko W, Lazenby WD, Zelano JA, et al. Effects of shav-ing methods and intraoperative irrigation on suppu-rative mediastinitis after bypass operations. Ann Tho-rac Surg 1992;53:305–309.

35. Bekar A, Korfali E, Dogan S, et al. The effect of hairon infection after cranial surgery. Acta Neurochir2001;143:533–537.

36. Axon AT. Potential hazards of hypochlorhydria in thetreatment of peptic ulcer. Scand J Gastroenterol 1986;Supp 122:17–21.

37. Taylor EW, Byrne DJ, Leaper DJ, et al. Antibiotic pro-phylaxis and open groin hernia repair. World J Surg1997;21:811–815.

38. Cainzos Fernandez M, Herrador V, Riestra C, PatelLesquereux J. Microbiology of surgical site infections.Presented at the 17th Annual Meeting of the SurgicalInfection Society of Europe, June 17–19, 2004, Cork,Ireland (abstract).

39. Kirkland KB, Briggs JP, Trivelte SL, et al. The impact ofsurgical site infections in the 1990s: Attributable mor-tality, excess length of hospitalization and extra cost. In-fect Control Hosp Epidemiol 1999;20:725–730.

Address reprint requests to:Dr. Ekrem Kaya

Hepatobiliary UnitDepartment of Surgery

Uludag University School of Medicine16059, Gorukle-Bursa, Turkey

E-mail: ekremkaya@uludag.edu.tr