Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-19T03:02:20.560Z Has data issue: false hasContentIssue false

A Risk Index for Sternal Surgical Wound Infection After Cardiovascular Surgery

Published online by Cambridge University Press:  02 January 2015

Michele Kohli
Affiliation:
Department of Public Health Sciences, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada Health Economics and Outcomes Research, Innovus Research Inc., Burlington, Ontario, Canada
Lilian Yuan
Affiliation:
Department of Public Health Sciences, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
Michael Escobar
Affiliation:
Department of Public Health Sciences, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
Tyrone David
Affiliation:
Division of Cardiovascular Surgery, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
Grant Gillis
Affiliation:
Infection Prevention and Control Unit, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada Quality Program, Canadian Standards Association International, Toronto, Ontario, Canada
Marta Garcia
Affiliation:
Infection Prevention and Control Unit, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
John Conly*
Affiliation:
Infection Prevention and Control Unit, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada Pathology and Laboratory Medicine, and Microbiology & Infectious Diseases, Division of Microbiology, Calgary Laboratory Services, Calgary Health Region and University of Calgary, Calgary, Alberta, Canada
*
Hospital Epidemiologist, University Health Network, Room 118, NU-13, Toronto General Hospital, 585 University Avenue, Toronto, Ontario, M5G 2C4, Canada

Abstract

Objectives:

To identify factors that increase the risk of sternal surgical wound infection after cardiovascular surgery and to develop a bedside clinical risk index using these factors.

Design:

A risk index was developed using clinical data collected from a cohort of 11,508 cardiac surgery patients and validated using three independent subsets of the data. With two of these subsets, we derived a logistic regression equation and then modified the scoring algorithm to simplify the calculation of patient risk scores by clinicians. The final subset was used to validate the index. The area under the receiver operating characteristic (aROC) curve was the primary measure of goodness of fit.

Setting:

Toronto General Hospital, a teaching hospital and the largest center for cardiac surgery in Ontario, Canada.

Patients:

Cardiac surgery patients receiving cardiopulmonary bypass between April 1, 1990, and December 31, 1995, who survived at least 6 days after surgery.

Results:

Variables that were used to construct the risk index included reoperation due to complication (odds ratio, 4.3; range, 1.9 to 8.5), diabetes (odds ratio, 2.4; range, 1.5 to 3.7), more than 3 days in the intensive care unit (odds ratio, 5.4; range, 3.2 to 8.7), and use of the internal mammary artery for revascularization (odds ratio, 3.2; range, 1.7 to 5.8). Validation showed that the index had an aROC curve of 0.64.

Conclusions:

The risk index described in this article allows clinicians to quickly stratify patients into four risk groups associated with an increasing risk of sternal surgical wound infection. It may be used perioperatively or as part of a wound infection surveillance system.

Type
Original Articles
Copyright
Copyright © The Society for Healthcare Epidemiology of America 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Mack, MJ. Perspectives on minimally invasive coronary artery surgery: current assessment and future directions. Int J Cardiol 1997;62(suppl 1):S73S79.CrossRefGoogle ScholarPubMed
2.Breyer, RH, Mills, SA, Hudspeth, AS, Johnston, FR, Cordell, AR. A prospective study of sternal wound complications. Ann Thorac Surg 1984;37:412416.CrossRefGoogle ScholarPubMed
3.Culliford, AT, Cunningham, JN, Zeff, RH, Ison, OW, Teiko, P, Spencer, FC. Sternal and costochondral infections following open-heart surgery. J Thorac Cardiovasc Surg 1976;72:714726.CrossRefGoogle ScholarPubMed
4.Farrington, M, Webster, M, Fenn, A, Phillips, I. Study of cardiothoracic wound infection at St. Thomas' hospital. Br J Surg 1985;72:759762.CrossRefGoogle ScholarPubMed
5.Kluytmans, JA, Mouton, JW, Ijzerman, EPF, et al. Nasal carriage of Staphylococcus aureus as a major risk factor for wound infections after cardiac surgery. J Infect Dis 1995;171:216219.CrossRefGoogle Scholar
6.Kustal, A, Ibrisim, E, Catav, Z, Tasdemir, O, Bayazit, K. Mediastinitis after open heart surgery: analysis of risk factors and management. J Cardiovasc Surg 1991;32:3841.Google Scholar
7.Miedzinski, LJ, Keren, G. Serious infectious complications of open-heart surgery. Can J Surg 1987;30:103107.Google ScholarPubMed
8.Miholic, J, Hudec, M, Domanig, E, et al. Risk factors for severe bacterial infections after valve replacement and aortocoronary bypass operations: analysis of 246 cases by logistic regression. Ann Thorac Surg 1985;40:224228.CrossRefGoogle ScholarPubMed
9.Nagachinta, T, Stephens, M, Reitz, B, Polk, BF. Risk factors for surgical-wound infection following cardiac surgery. J Infect Dis 1987;156:967973.CrossRefGoogle ScholarPubMed
10.Sarr, MG, Gott, VL, Townsend, TR. Mediastinal infection after cardiac surgery. Ann Thorac Surg 1984;38:415423.CrossRefGoogle ScholarPubMed
11.Shuhaiber, H, Chugh, T, Portolan-Shuhaiber, S, Ghosh, D. Wound infection in cardiac surgery. J Cardiovasc Surg 1987;28:139142.Google ScholarPubMed
12.Loop, FD, Lytle, BW, Cosgrove, DM, et al. Sternal wound complications after isolated coronary artery bypass grafting: early and late mortality, morbidity, and cost of care. Ann Thorac Surg 1990;49:179187.CrossRefGoogle ScholarPubMed
13.Ottino, C, De Paulis, R, Pansini, S, et al. Major sternal wound infection after open-heart surgery: a multivariate analysis of risk factors in 2,570 consecutive operative procedures. Ann Thorac Surg 1987;44:173179.CrossRefGoogle Scholar
14.Higgins, TL, Estafanous, FG, Loop, FD, Beck, GJ, Blum, JM, Paranandi, L. Stratification of morbidity and mortality outcome by preoperative risk factors in coronary artery bypass patients: a clinical severity score. JAMA 1992;262:23442348.CrossRefGoogle Scholar
15.Sethi, GK, Miller, DC, Souchek, J, et al. Clinical, hemodynamic, and angio-graphic predictors of operative mortality in patients undergoing single valve replacement. J Thorac Cardiovasc Surg 1987;93:884897.CrossRefGoogle Scholar
16.Stahle, E, Tammelin, A, Bergstrom, R, Hambreus, A, Nystrom, SO, Hansson, HE. Sternal wound complications: incidence, microbiology and risk factors. Eur J Cardiothorac Surg 1997;11:11461153.CrossRefGoogle ScholarPubMed
17.Miller, ME, Langefield, CD, Tierney, WM, Hui, SL, McDonald, CJ. Validation of probabilistic predictions. Med Decis Making 1993;13:4958.CrossRefGoogle ScholarPubMed
18.Jennett, RJ, Warford, HS, Kreinick, C, Waterkotte, GW. Apgar index: a statistical tool. Am J Obstet Gynecol 1981;140:206212.CrossRefGoogle ScholarPubMed
19.Knaus, WA, Draper, EA, Wagner, DP, Zimmerman, JE. APACHE II: a severity of disease classification system. Crit Care Med 1985;13:818829.CrossRefGoogle ScholarPubMed
20.Culver, DH, Horan, TC, Gaynes, RP, et al. Surgical wound infection rates by wound class, operative procedure and patient risk index. JAMA 1991;91(3B suppl):152S157S.CrossRefGoogle ScholarPubMed
21.Roy, MC, Herwaldt, LA, Embrey, R, Kuhns, K, Wenzel, RP. Does the Centers for Disease Control and Prevention's NNIS system risk index stratify patients undergoing cardiothoracic operations by their risk of surgical-site infection? Infect Control Hosp Epidemiol 2000;3:186190.CrossRefGoogle Scholar
22.Horan, T, Gaynes, RP, Martone, WJ, Jarvis, WR, Emori, TG. CDC definitions of nosocomial surgical site infections, 1992: a modification of CDC definitions of surgical wound infections Infect Control Hosp Epidemiol 1992;13:606608.CrossRefGoogle ScholarPubMed
23.Hosmer, DW, Lemeshow, S. Applied Logistic Regression. Toronto, Ontario, Canada: John Wiley & Sons; 1989.Google Scholar
24.Hanley, JA, McNeil, BJ. The meaning and use of the area under a receiver operating characteristic (ROC) curve. Radiology 1982;143:2936.CrossRefGoogle Scholar
25.Hanley, JA, McNeil, BJ. A method of comparing the areas under receiver operating characteristic curves derived from the same cases. Radiology 1983;148:839843.CrossRefGoogle ScholarPubMed
26.Vida, S. A computer program for non-parametric receiver operating characteristic analysis. Comput Methods Programs Biomed 1993;40:95101.CrossRefGoogle ScholarPubMed
27.Wasson, JH, Sox, HC, Neff, RK, Goldman, L. Clinical prediction rules: applications and methodological standards. N Engl J Med 1985;313:793799.CrossRefGoogle ScholarPubMed
28.Tu, JV, Mazer, CD, Levinton, C, Armstrong, PW, Naylor, CD. A predictive index for length of stay in the intensive care unit following cardiac surgery. CMAJ 1994;151:177185.Google ScholarPubMed
29.Tu, JV, Sykora, K, Naylor, CD. Assessing the outcomes of coronary artery bypass graft surgery: how many risk factors are enough? J Am Coll Cardiol 1997;30:13171323.CrossRefGoogle Scholar
30.Harrel, F. Regression coefficients and scoring rules. J Clin Epidemiol 1996;148:473477.Google Scholar
31.Haley, RW. Nosocomial infections in surgical patients: developing valid measure of intrinsic patient risk. JAMA 1991;91(suppl 3B):145S151S.CrossRefGoogle ScholarPubMed
32.Casey, J, Flinn, WR, Yao, JST, Fahey, V, Pawlowski, J, Bergan, JJ. Correlation of immune and nutritional status with wound complications in patients undergoing vascular operations. Surgery 1983;93:822827.Google ScholarPubMed
33.Hazelrigg, SR, Wellons, HA, Schneider, JA, Kolm, P. Wound complications after median sternotomy. J Thorac Cardiovasc Surg 1989;98:10961099.CrossRefGoogle ScholarPubMed
34.Grossi, EA, Esposito, R, Harris, LJ, et al. Sternal wound infections and use of internal mammary artery grafts. J Thorac Cardiovasc Surg 1991;102:342347.CrossRefGoogle ScholarPubMed
35.Johnson, WD, Pablo, MP, Kayser, K. Coronary artery surgery in diabetics: 261 consecutive patients followed four to seven years. Am Heart J 1982;104:823.CrossRefGoogle ScholarPubMed
36.Paris Mediastinitis Study Group. Risk factors for deep sternal wound infection after sternotomy: a prospective, multicenter study. J Cardiovasc Surg 1996;111:12001207.Google Scholar
37.Meakins, JL, ed. Surgical Infections: Diagnosis and Treatment. New York: Scientific American; 1994.Google Scholar
38.Trick, WE, Scheckler, WE, Tokars, JI, et al. Modifiable risk factors associated with deep sternal site infection after coronary artery bypass grafting. J Thorac Cardiovasc Surg 2000;119:108114.CrossRefGoogle ScholarPubMed
39.Ulicny, KS, Hiratzka, LF, Williams, RB, et al. Sternotomy infection: poor prediction by acute phase response and delayed hypersensitivity. Ann Thorac Surg 1990;50:949958.CrossRefGoogle ScholarPubMed
40.Rosendorf, LL, Daicoff, G, Baer, H. Sources of gram-negative infection after open-heart surgery. J Thorac Cardiovasc Surg 1974;67:195201.CrossRefGoogle ScholarPubMed
41.Murphy, PJ, Connery, C, Hicks, GL, Blumberg, N. Homologous blood transfusion as a risk for postoperative infection after coronary artery graft operations. J Thorac Cardiovasc Surg 1992;104:10921099.CrossRefGoogle ScholarPubMed
42.Orenstein, P, Amihod, B, Consolacian, N, Miller, MA. Surgical site infection surveillance by means of post-discharge telephone interviews. Presented at the 8th Annual Meeting of the Society for Healthcare Epidemiology of America; April 5-7,1998; Orlando, FL.Google Scholar