Risk Analysis of Deep Sternal Wound Infection and Mediastinitis in Cardiac Surgery

Abstract

We read with interest the recent article by Gummert et al. on risk factor analysis of mediastinitis in cardiac surgery [1]. Based on a 1.44 % incidence of deep sternal wound infection (DSWI) in 9,303 patients undergoing cardiac surgery through full sternotomy, the group identifies use of one or two internal thoracic arteries (ITA) as bypass conduits, presence of diabetes, and increased body mass index (BMI) as significant independent perioperative risk factors for DSWI [1].The Gummert report does not mention two recent reviews listing over 60 risk factors, including but not restricted to diabetes mellitus and ITA [2, 3]. They do not discuss the published conclusions of other investigators that multiple ITA bypasses can be performed without excessive morbidity, with low reoperation rates, and good long-term outcome [4]. Gummert's study suffers from a methodological problem common to research in this area -it concentrates on a limited number of DSWI risk factors, but does not consider all the risk factors reported in large groups of sternotomy patients [2,3]. The modern understanding of DSWI lacks a validated concept of either the most significant risk factors or the most effective prevention guidelines for DSWI; recommendations have been typically based on theoretic rationales and suggestive evidence, with little resort to scientifically developed information [2,3]. The Gummert study does little to improve this situation.Gummert et al. do not list details of the particular type of sternotomy closure used in their series. They create an impression that sternal osteoporosis and suboptimal sternal closure were not considered among the risk factors influencing the DSWI incidence. The question of whether sternal instability or infection is the primary underlying problem in DSWI and mediastinitis re-mains unanswered. The recent literature suggests that closure stability can be improved by increasing the number of sternotomy wires [2]. Gummert et al. did not detail the technique of sternal debridement and reclosure during the course of mediastinitis, or whether this might have played a role in the 41 % mortality rate when mediastinal structures were revised more than twice [1]. A more stable mechanical fixation of the sternotomy, once dehiscence and mediastinitis occur, reduces the incidence of further complications [3,5]. Gummert's study provides some insight into only a few of the known DSWI risk factors. Future studies in this problem should exhaustively consider and analyze the entire series of known risk factors described in the literature [2,3] in order to evaluate possible cross-potentiations and help reduce the incidence of life-threatening DSWI. References 1 Gummert JF, Barten MJ, Hans C, Kluge M, Doll N, Walther T, Hentschel B, Schmitt DV, Mohr FW, Diegeler A. Mediastinitis and cardiac surgery -an updated risk factor analysis in 10,373 consecutive adult patients. Thorac Cardiovasc Surg 2002; 50: 87 -91 2 Losanoff JE, Jones JW, Richman BW. Primary closure of median sternotomy: techniques and principles. Cardiova...

The role of hyperbaric oxygen therapy in the treatment of sternal wound infection

“…In patients who develop mediastinitis after re-operation, gram-negative organisms, particularly rods, are commonly identified [9]. Methicillin resistant S. aureus is increasing in prevalence and is now found to be the infecting organism 'relatively frequently' [10]. sternal infection.…”

“…As soon as the diagnosis is made specimens should be collected for microbiological analysis and broad-spectrum antibiotics instituted, based on local patterns of resistance and gram stain results. A combination of a cephalosporin and vancomycin has been recommended as empirical therapy until sensitivities are known [10]. The heterogeneity of wounds dictates that the extent of debridement and reconstruction is tailored to the operative findings.…”

“…A range of overall surgical strategies have been used, from reconstruction in every case, to a more selective approach depending on findings [40]. Reconstruction techniques include sternal rewiring [10], pectoralis or rectus muscle and omental flap rotation [39,41,42].…”

Using Closed Incision Negative Pressure Therapy Specialty Dressings over Incisions following Sternal Dehiscence Reconstruction

“…3,4 However, surgical site complications (SSCs) after median sternotomy, such as deep sternal wound infections (DWSIs), may occur in 0.2%–8% of cases, and sternal dehiscence may have an incidence of 0.06%–12.50%. 5–9 If SSCs are left unresolved, perioperative mortality may have a ceiling as high as 47%. 8,9…”

Deep Sternal Wound Infection and Risk Analysis - What Do We Really Know?

“…

We read with great interest the critique of Losanoff et al [1] regarding our article on risk factor analysis for deep sternal wound infection (DSWI) following cardiac surgery [2]. Their comments, however, fail to be relevant.

…”