Vacuum-assisted closure to treat deep sternal wound infection following cardiac surgery

Deep sternal wound infection is a devastating and potentially lethal complication following cardiac surgery. Established treatment may involve debridement, packing, delayed closure, plastic reconstruction, re-wiring and irrigation, depending on the severity of infection. The authors prefer early debridement and rewiring with irrigation if possible. If this method fails the results are often poor. Vacuum-assisted closure (VAC) of complex infected wounds has recently gained popularity among various surgical specialties. This article describes the successful application of this novel technique in a patient with infected sternal dehiscence who had failed to respond to conventional treatment.     

Endogenously acquired deep sternal wound infection after congenital cardiac surgery

A 10-month-old child from the Middle East received complete correction for tetralogy of Fallot. Despite an initially uneventful postoperative course, he developed severe deep sternal wound infection after 7 days. This complication was endogenously acquired caused by a resistant and rarely present in Europe, Streptococcus pneumonia. Following surgical debridement, betadine rinsing for 3 days and with a course of specific antibiotic therapy, the patient was discharged in good health.     

Negative-pressure wound therapy following cardiac surgery: bleeding complications and 30-day mortality in 176 patients with deep sternal wound infection

Negative-pressure wound therapy (NPWT) has been used for the treatment of deep sternal wound infection (DSWI) with promising results. However, questions have been raised regarding the potential risk of right ventricle (RV) rupture during treatment. In the present study, we evaluate our clinical experience of NPWT focusing on RV rupture and major bleeding complications and its potentially negative impact on 30-day mortality during an 11-year period. Serious bleeding complications during NPWT were reviewed for 176 patients treated for DSWI between January 1999 and April 2010. The 30-day mortality following DSWI was 1.1% (2/176). Four patients (2.3%) suffered bleeding from the RV rupture during NPWT of the sternal wound (two spontaneous and two debridement related). Furthermore, two patients had debridement-related bleedings from the venous bypass grafts during wound dressing change. The very low 30-day mortality (1.1%) following DSWI supports the use of NPWT. Overall, even if major bleeding complications may occur, the risk of RV rupture seems to be outweighed by the benefit of superior infection control. However, surgical experience is recommended when debriding sternal wounds and we recommend the use of a wound dressing, such as paraffin gauze, in order to protect the RV from direct contact with the polyurethane foam.     

Management of deep sternal wound infection after cardiac surgery--Hanuman syndrome

Deep sternal wound infection following open-heart surgery caused sternal osteitis in eight patients and mediastinitis in 27 during 1980-1989. The incidence of such infection was 0.5%. Infection was more common during the last 2 years than in 1980-1987 (0.8% vs. 0.4%), and when bilateral internal mammary artery grafts were dissected (3.2% vs. 0.6% when only one internal mammary artery was used). Cure of mediastinitis was achieved by primary closed irrigation in four of 13 patients and by primary open treatment in five of ten. Muscle flap was employed in totally ten patients and omentum in four before final elimination of infection. Of the 27 patients with mediastinitis, eight (30%) died in the post-operative period of cardiac failure (3 cases), disseminated infection (2), bleeding (2) or aspiration (1). The 5-year survival rate was 43%. Prosthetic value endocarditis caused one late death and necessitated one reoperation. If eradication of postoperative mediastinitis is not achieved by early diagnosis, debridement and closed irrigation, transposition of muscle or omentum should be considered.     

Major bleeding complicating deep sternal infection after cardiac surgery

OBJECTIVES: This study was undertaken to determine the incidence and outcome of major bleeding complicating deep sternal infection after cardiac surgery, to identify predisposing factors and means of prevention, and to clarify management options. METHODS: This was a retrospective study of 10,863 consecutive patients, of whom 213 (2.18%) acquired deep sternal infection. With 43 additional referrals, the total number of patients with deep sternal infection was 280. Deep sternal infection was managed by a two-stage scheme. Major bleeding was considered to be bleeding that occurred during or after operation for deep sternal infection from the heart, great vessels, or grafts, or bleeding requiring urgent exploration. RESULTS: Fifteen patients (5.36%) had major bleeding. The incidences of deep sternal infection and bleeding were highest among patients undergoing coronary artery bypass grafting. Thirteen patients had underlying diseases (type 2 diabetes in 9 cases). Deep sternal infection was diagnosed a median of 15 days after reoperation. Bleeding originated from the right ventricle in 9 patients. In 4 patients bleeding was iatrogenic during surgery for wire removal (n = 2) or reconstruction (n = 2). In 11 it occurred 15 minutes to 15 days (median 2 days) after wire removal, as a result of shearing forces in 7 cases and of infection only in 4 cases. Three patients died immediately. The other 12 were operated on, 6 with complete cardiopulmonary bypass, 2 with femoral cannulation, and 4 without cardiopulmonary bypass. The immediate mortality was 26.7%; the overall mortality was 53.3%. The median length of hospitalization of surviving patients was 38 days. CONCLUSIONS: The probability of development of major bleeding in patients with deep sternal infection was unrelated to the primary operation. The mortality associated with this complication was high. Meticulous technique during wire removal may decrease the risk of major bleeding. The impacts of cardiopulmonary bypass and of the technique and timing of sternal reconstruction remain undetermined.     

Deep sternal wound infection requiring revision surgery: impact on mid-term survival following cardiac surgery.

OBJECTIVE: To assess the impact of deep sternal wound infection on in-hospital mortality and mid-term survival following adult cardiac surgery. METHODS: Prospectively collected data on 4586 consecutive patients who underwent a cardiac surgical procedure via a median sternotomy from 1st January 2001 to 31st December 2005 were analysed. Patients with a deep sternal wound infection (DSWI) were identified in accordance with the Centres for Disease Control and Prevention guidelines. Nineteen variables (patient-related, operative and postoperative) were analysed. Logistic regression analysis was used to calculate a propensity score for each patient. Late survival data were obtained from the UK Central Cardiac Audit Database. Mean follow-up of DSWI patients was 2.28 years. RESULTS: DSWI requiring revision surgery developed in 1.65% (76/4586) patients. Stepwise multivariable logistic regression analysis identified age, diabetes, a smoking history and ventilation time as independent predictors of a DSWI. DSWI patients were more likely to develop renal failure, require reventilation and a tracheostomy postoperatively. Treatment included vacuum assisted closure therapy in 81.5% (62/76) patients and sternectomy with musculocutaneous flap reconstruction in 35.5% (27/76) patients. In-hospital mortality was 9.2% (7/76) in DSWI patients and 3.7% (167/4510) in non-DSWI patients (OR 1.300 (0.434-3.894) p=0.639). Survival with Cox regression analysis with mean propensity score (co-variate) showed freedom from all-cause mortality in DSWI at 1, 2, 3 and 4 years was 91%, 89%, 84% and 79%, respectively compared with 95%, 93%, 90% and 86%, respectively for patients without DSWI ((p=0.082) HR 1.59 95% CI (0.94-2.68)). CONCLUSION: DSWI is not an independent predictor of a higher in-hospital mortality or reduced mid-term survival following cardiac surgery in this population.     

Preoperative carriage and postoperative same-species sternal wound infection after cardiac surgery

Sternal wound infection (SWI) after cardiac surgery remains an important problem. Prediction of pathogens involved in such infection could guide antibiotics. From April 1, 2006 to December 31, 2008, retrospectively, we evaluated the diagnostic value of preoperative methicillin-sensible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA) or multi-drug resistant Gram-negative bacillus (MDRGNB) carriage to predict same-pathogens involved in postoperative SWI. All patients referred for elective cardiac surgery were screened using multisite (nares, axillae, rectal) sampling at admission to detect MSSA, MRSA, and MDRGNB. Of the 1895 patients addressed, 425 patients (22.4%) were colonized at admission. Preoperative carriers more frequently developed SWI than non-carriers, respectively, 11% vs. 5.5% (P<0.05). Because of the small sample, MDRGNB carriers could not be analyzed. For prediction of MSSA SWI with preoperative MSSA carriage, the area under the receiver operating characteristic (ROC) curve was 0.720 (95% confidence interval (CI), 0.364-0.796) and 0.710 (95% CI, 0.623-0.787) for prediction of MRSA SWI with preoperative MRSA carriage. Preoperative MSSA carriage is frequent but preoperative MRSA or MDRGNB carriage remains infrequent. The ability of preoperative carriage to predict a same-pathogen-postoperative SWI was low and should not be used to guide empirical antibiotherapy.     

Primary treatment of deep sternal wound infection after cardiac surgery: a survey of German heart surgery centers

There are various primary treatment modalities of managing deep sternal wound infection (DSWI) following cardiac surgery, namely surgical debridement with primary reclosure in conjunction with irrigation, Vacuum-assisted closure (V.A.C. therapy, and primary or delayed flap closure. The purpose of this study was to assess whether there is consensus of the primary management of DSWI using one method as a single line therapy or a combination of these procedures. Therefore, a questionnaire with regards to the primary treatment modalities of DSWI was distributed to all 79 German heart surgery centers. All replied to the questionnaire. V.A.C. is used in 28/79 (35%) heart centers as the 'first-line' treatment, 22/79 (28%) perform primary reclosure in conjunction with a double-tube irrigation/suction system, and in 29/79 (37%) clinics both treatment options were used according to intraoperative conditions. Mostly, as a primary management of DSWI two treatment modalities are mainly in use: primary reclosure coupled with a double-tube suction/irrigation system and V.A.C. therapy. The current understanding is based purely on retrospective studies, not evidence-based medicine. Since prospective randomized studies have not yet been performed, controlled clinical trials comparing these treatment modalities are pivotal to define evidence for patients presenting with DSWI.     

Risk factors and treatment of deep sternal wound infection after cardiac operation.

OBJECTIVE: Although deep sternal wound infection (DSWI) after cardiac surgery is infrequent, its consequences are serious. The purposes of this study were to define the risk factors, and to establish the best surgical treatment for DSWI. METHODS: Retrospective analysis for 863 patients who underwent cardiac surgery was performed. The patients were divided into the DSWI group (n=17) and the non-infection group (n=846). Preoperative, perioperative, and postoperative variables were compared between the two groups using univariate and multivariate logistic regression analysis. The modality of treatment for DSWI was also analyzed. RESULTS: The incidence of DSWI was 1.97%. Independent predictors for DSWI were concomitant coronary artery bypass grafting (CABG) with valve or aortic surgery [odds ratio, 4.1; 95% confidence interval, (1.1, 15.1)] and postoperative use of intraaortic balloon pumping [4.4, (1.6, 12.3)]. An independent predictor in isolated CABG patients was emergency operation [10.9, (2.7, 44.7)]. Four of 17 patients died. Methicillin-resistant Staphylococcus aureus (MRSA) was cultured from 10 (58.8%) patients, and all four of the deceased subjects died of its infection. Seventeen patients were treated by debridement, primary closure, and the addition of an omentum or muscle flap if necessary. CONCLUSIONS: Patients in poor perioperative condition are at high risk for the development of this infection. It was difficult to establish the best treatment, owing to the small series of this study. Mortality and morbidity of DSWI due to MRSA was high.     

Prevention and management of deep sternal wound infection

Deep sternal wound infection (DSWI) is an uncommon but serious complication of median sternotomy in cardiac surgery, associated with significant mortality and morbidity. We performed a retrospective review of 30,102 consecutive cardiac surgical patients operated on at our institution from 1990 to 2003 and found an incidence of DSWI of 0.77%. The in-hospital mortality rate was 6.9% for DSWI patients versus 2.8% for patients without DSWI (P = 0.0002). Multivariable predictors for development of DSWI were old age, diabetes, previous stroke or TIA, and congestive heart failure. The use of bilateral internal thoracic artery (BITA) grafts increased the risk of DSWI in patients undergoing coronary artery bypass surgery, particularly in those with congestive heart failure alone or with diabetes. Skeletonization of BITA grafts resulted in a lower risk of DSWI, comparable to nondiabetic patients (1.3% versus 1.6%, P = 0.8). Patients with DSWI were treated with either sternal debridement and primary closure or sternectomy with myocutaneous flap reconstruction, resulting in a 6-month freedom from adverse event rate of 76% in both groups.     

The association between tracheostomy and sternal wound infection in postoperative cardiac surgery patients

Purpose

To investigate whether tracheostomy increases the risk of sternal wound infection (SWI) post cardiac surgery.

Methods

All patients undergoing cardiac surgery via median sternotomy from September 1997 to October 2010 were included in this retrospective observational study. Primary exposure was tracheostomy performed during admission to the cardiac surgical intensive care unit. The primary outcome was SWI during hospital admission. Multivariable logistic regression was used to determine if tracheostomy was an independent predictor of SWI. Restriction and propensity score analyses were then used to assess if tracheostomy is a causal risk factor for SWI.

Results

Four hundred and eleven of 18,845 patients (2.2%) were treated with tracheostomy. Incidences of SWI in tracheostomy and non-tracheostomy groups were 19.5% (80/411) and 0.8% (154/18,434), respectively. Using multivariable logistic regression analysis, tracheostomy was found to be an independent predictor of SWI (odds ratio [OR] 2.8; 95% confidence interval [CI] 1.9 to 4.2). In an analysis restricted to respiratory failure patients, tracheostomy was associated with sternal wound infection (OR 3.4; 95% CI 2.4 to 4.9). When the analysis was stratified by the risk of receiving tracheostomy as represented by propensity score (PS), 46 patients (12%) in the intermediate risk category (PS 0.2-0.4) had SWIs (adjusted OR 2.97; 95% CI 1.6 to 5.6), and 52 patients (14%) in the highest risk category (PS > 0.4) had SWIs (OR 1.52; 95% CI 0.85 to 2.87).

Discussion

Our single-centre observational study of cardiac surgery patients found tracheostomy to be an independent risk factor for SWI. Our analysis showed a robust association when restricted to patients with respiratory failure and after the population was stratified by the propensity to have a tracheostomy.     

Experience with Vacuum-assisted closure of sternal wound infections following cardiac surgery and evaluation of chronic complications associated with its use

OBJECTIVES: We report our experience in use of Vacuum-assisted closure therapy (VAC) in the treatment of poststernotomy wound infection with emphasis on recurrent wound-related problems after use of VAC and their treatment. METHODS: Between July 2000 and June 2003, 2706 patients underwent various cardiac procedures via median sternotomy. Forty-nine patients with postoperative sternal wound infection (1.9%) were managed with VAC. Wounds were classified as either superficial sternal wound infection (28 patients) or deep sternal wound infection (21 patients). In the superficial sternal wound infection group, 23 patients had VAC as definitive treatment (GroupA), while five patients (Group B) had VAC followed by surgical closure. Similarly, in the deep sternal wound infection group, 12 patients had VAC as definitive treatment (Group C), while nine patients had VAC followed by surgical closure (Group D). Patients were discharged after satisfactory wound closure. Upon discharge patients were followed up at interval of three to six months. Recurrent sternal problems when identified were investigated and additional surgical procedures were carried out when necessary. RESULTS: There were nine deaths, all due to unrelated causes except in one patient who died of right ventricular rupture (Group C). Nine patients in Group A had recurrent wound problems of which six had VAC system for > 21 days. Three patients underwent extensive debridement due to sternal osteomyelitis. All eight patients in Group B presented with chronic wound-related problems and underwent multiple debridements. Four patients had laparoscopic omental flaps. In contrast 14 patients (Group B and D) who were treated with shorter duration of VAC followed by either a flap or direct surgical closure, did not present with recurrent problems. CONCLUSION: VAC therapy is a safe and reliable option in the treatment of sternal wound infection. However, prolonged use of VAC system as a replacement for surgical closure of sternal wound appears to be associated with recurrent problems of the sternal wound. Strategy of use of VAC for a short duration followed by early surgical closure appears favorable.     

Vacuum-assisted wound closure in the management of deep sternal wound infection

We herein present a case who underwent vacuum-assisted wound closure (VAC) therapy for post-sternotomy mediastinitis. A 71-year-old female with chronic renal failure on dialysis underwent a graft replacement of the ascending aortic aorta for the treatment of an acute aortic dissection. After she was discharged from the hospital, a purulent discharge was noted to occur from the median sternal wound. The wound was therefore reopened and all sternal wires were removed. Thereafter, polyurethane foam which was shaped to fit the defect was placed within the cavity. The area was covered with adhesive drape and suction drainage was carried out at -100 mmHg. The polyurethane foam was replaced every few days. The wound was finally closed using a muscle flap at 49 days after surgery. VAC therapy is therefore considered to be a useful treatment modality for deep sternal wound infections.     

Adjuvant treatment of deep sternal wound infection with collagenous gentamycin

BACKGROUND: The treatment of deep sternal wound infections remains controversial. Currently advocated procedures carry the risk of reinfections. The significance of local antibiotic-releasing systems as an adjuvant therapy to avoid reinfections is the subject of the presented study. METHODS: Forty-two patients with deep sternal wound complication were treated with radical wound debridement, sternal refixation, retrosternal suction drainage, bilateral pectoralis major muscle flaps, and placement of collagenous drug carrier loaded with gentamycin (Sulmycin Implant) underneath, above, and between the sternal edges. RESULTS: No treatment failure and death were observed in our patients. Side effects after adjuvant treatment with collagenous gentamycin were not detected. CONCLUSIONS: The preliminary results of adjuvant therapy with collagenous gentamycin in combination with surgical debridement leads to excellent results in the treatment of early deep sternal wound infections with no death and no primary treatment failures. This technique is easy to perform, reliable, and safe. For final judgment controlled randomized trials are mandatory.