Evaluation of risk factors for hospital mortality and current treatment for poststernotomy mediastinitis. Gen Thorac Cardiovasc Surg. 2011;59:261-267. [PMID: 21484552 DOI: 10.1007/s11748-010-0727-3]

Vacuum-assisted closure therapy for the management of deep sternal wound complications: A systematic review and meta-analysis

BACKGROUND

Vacuum-assisted closure (VAC) therapy has become a popular treatment option for wound healing. The aim of this meta-analysis was to assess the use of VAC therapy as a bridge before the definitive treatment for the management of deep sternal wound complications.

METHODS

A systematic literature review and meta-analysis were performed in PubMed and Embase. Outcomes of interest included mortality, treatment failure, length of hospital stay (LOS), length of intensive care unit (ICU) stay and cost of treatment.

RESULTS

Twenty-two studies involving 1980 patients were included in the quantitative synthesis of this meta-analysis. Patients treated with VAC had significantly lower overall mortality [1738 patients; Risk ratio [RR] = 0.36 (95% confidence interval [CI]: 0.25, 0.51)], treatment failure [1210 patients; RR = 0.26 (95% CI: 0.19, 0.37)], LOS [498 patients; (standard mean difference = -0.44 (95% CI: -0.81, -0.07)] and ICU stay [309 patients; (standard mean difference = -0.34 (95% CI: -0.67, -0.01)] compared to that of non-VAC patients. VAC therapy was associated with reduced cost of treatment per patient compared with that of non-VAC therapies (reductions of 3600 USD, 6000 USD and 8983 USD in the reported studies).

CONCLUSIONS

VAC therapy as an adjunct in the definitive treatment of patients with deep sternal wound complications was associated with lower mortality, treatment failure, LOS, ICU stay and cost of treatment when compared with a non-VAC approach. Randomised controlled trials would be essential to confirm these findings.

[Treatment regimen for deep sternal wound infections after cardiac surgical interventions in an interdisciplinary approach]

The aim of this article is to present the importance of a structured and situation-adapted approach based on the diagnostic and therapeutic strategy in the interdisciplinary treatment of 54 patients with deep sternal wound infections (DSWI) after cardiac surgical interventions and the results achieved. The patients were 41 men and 13 women with an average age of 65.1 years, who developed a DSWI after a cardiac surgical intervention during the period 2003-2016. The treatment strategy included a thorough debridement including the removal of indwelling foreign material, the reconstruction with a stable re-osteosynthesis after overcoming the infection and if necessary, situation-related surgical flaps for a defect coverage with a good blood supply and mandatory avoidance of dead spaces. A total of 146 operations were necessary (average 2.7 operations/patient, range 1-7 operations). In 24.1 % of the cases a one-stage approach could be carried out. In 41 patients negative pressure wound therapy (NPWT) with programmed sponge changing was used for wound conditioning (mean 5 changes, standard deviation, SD± 5.6 changes over 22 days, SD± 23.9 days, change interval every 3-4 days in 40.7% of the cases). In 33 patients a bilateral myocutaneous pectoralis major flap was used, in 4 patients a vertical rectus abdominis myocutaneous (VRAM) flap and in 7 patients both were carried out. A total of 43 osteosynthesis procedures were carried out on the sternum with fixed-angle titanium plates. Of the patients 7 died during intensive care unit treatment (total mortality 13 %, n = 5, 9.3 % ≤ 30 days) or in the later course. Of the patients 47 (87.1 %) could be discharged with a cleansed infection. In 2 patients the implant was removed after 2 years due to loosening.

Efficacy of incisional negative pressure therapy in preventing post-sternotomy wound complications

BACKGROUND

Sternal wound infections represent a source of significant morbidity and mortality following median sternotomy. The use of incisional negative pressure wound therapy in prevention has yet to be elucidated.

METHODS

A retrospective study was conducted before and after a universal wound care protocol was implemented including the prophylactic use of negative pressure wound therapy (NPWT). The primary endpoint was sternal infections within 90 days of the index operation.

RESULTS

In the control period, there was a 3.0% rate of sternal infection within 90 days compared to 0.8% in the intervention period (p < 0.001). An odds ratio of 0.25 (95% confidence interval 0.11, 0.57; p < 0.001) in the intervention period as compared to the control period was demonstrated.

CONCLUSIONS

The use of a standardized wound care protocol including the universal application of NPWT for patients undergoing cardiac surgery with median sternotomy was an independent predictor of decreased rates of sternal infection.

Modification of Vancomycin Dosing in Cardiac Surgery With Cardiopulmonary Bypass

This study aims to assess the risk factors for insufficient vancomycin concentrations for its prophylactic use in adult patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) and to modify the dosing regimen to achieve appropriate plasma concentrations. A total of 27 patients with vancomycin dosing of 1 to 1.5 g based on a weight cutoff of 67 kg were included, of which only 13 (48.15%) had vancomycin plasma concentration >15 mg/L at surgical closure. Risk factors of vancomycin concentration <15 mg/L at surgical-site closure were confirmed by multivariate logistic regression analysis, which showed that CPB duration was an independent predictor. Patients with CPB duration >4 hours had significantly lower vancomycin concentrations and lower proportion in achieving target vancomycin concentration at the end of CPB and surgical closure. For patients with CPB >4 hours, the modified dosing regimen that a second dose of 0.5 to 0.75 g added at 4 hours since the onset of CPB improved the target achievement of vancomycin concentration at surgical closure. Taken together, CPB duration >4 hours was the risk factor for insufficient vancomycin concentration at surgical closure, while our modified dosing could improve the vancomycin concentrations for its prophylactic use in patients undergoing cardiac surgery with CPB.

Population pharmacokinetics of three alternative prophylactic antibiotics during cardiac surgery with extracorporeal circulation

AIMS

The aim of this pharmacokinetic study was to describe and quantify population pharmacokinetics of three antibiotics, cefazolin, ampicillin, and ciprofloxacin, used as antibacterial prophylaxis during cardiovascular surgery with the use of extracorporeal circulation (ECC).

METHODS

Adult patients undergoing cardiac surgery with ECC were enrolled to this prospective, pharmacokinetic study. An intravenous bolus of 2 g of ampicillin, 2 g of cefazolin or 400 mg of ciprofloxacin was administered 60-30 min before surgery. Blood samples were collected at 15, 30, 45, 60, 120 and 180 min after the administration and at the end of the surgery. Plasma concentrations of the antibiotics were measured using HPLC methods. Serum concentration-time profiles were analyzed using nonlinear mixed-effects modeling approach.

RESULTS

A total of 54 patients were enrolled into the study, 20 with ampicillin, 25 cefazolin and 9 ciprofloxacin. For all antibiotics, population pharmacokinetic models have been successfully developed.

CONCLUSION

We identified estimated glomerular filtration rate (eGFR) as the main factor determining the achievement of the pharmacokinetic/pharmacodynamic (PK/PD) target in ampicillin or cefazolin and body weight in ciprofloxacin prophylaxis during cardiac surgery with ECC support.

Prevention, Diagnosis and Management of Post-Surgical Mediastinitis in Adults Consensus Guidelines of the Spanish Society of Cardiovascular Infections (SEICAV), the Spanish Society of Thoracic and Cardiovascular Surgery (SECTCV) and the Biomedical Research Centre Network for Respiratory Diseases (CIBERES)

This is a consensus document of the Spanish Society of Cardiovascular Infections (SEICAV), the Spanish Society of Thoracic and Cardiovascular Surgery (SECTCV) and the Biomedical Research Centre Network for Respiratory Diseases (CIBERES). These three entities have brought together a multidisciplinary group of experts that includes anaesthesiologists, cardiac and cardiothoracic surgeons, clinical microbiologists, infectious diseases and intensive care specialists, internal medicine doctors and radiologists. Despite the clinical and economic consequences of sternal wound infections, to date, there are no specific guidelines for the prevention, diagnosis and management of mediastinitis based on a multidisciplinary consensus. The purpose of the present document is to provide evidence-based guidance on the most effective diagnosis and management of patients who have experienced or are at risk of developing a post-surgical mediastinitis infection in order to optimise patient outcomes and the process of care. The intended users of the document are health care providers who help patients make decisions regarding their treatment, aiming to optimise the benefits and minimise any harm as well as the workload.

Antibiotic-loaded bone cement combined with vacuum sealing drainage to treat deep sternal wound infection following cardiac surgery: the first case report

Background

Deep sternal wound infection (DSWI) is a rare but serious complication after median sternotomy, and treatment success depends mainly on surgical experience. Here we first present a case of a patient successfully treated for antibiotic-loaded bone cement (ALBC) combined with vacuum sealing drainage (VSD) of DSWI.

Case presentation

This case report presented a patient who underwent open heart surgery, and suffered postoperatively from a DSWI associated with enterococcus cloacae. Focus debridement combined with ALBC filling and VSD was conducted in stage I. Appropriate antibiotics were started according to sensitivity to be continued for 2 weeks until the inflammatory markers decreased to normal. One month after the surgery, patient’s wound was almost healed and was discharged from hospital with a drainage tube. Two months after the stage I surgery procedure, the major step was removing the previous ALBC, and extensive debridement in stage II. The patient fully recovered without further surgical treatment.

Conclusions

The results of this case suggest that ALBC combined with VSD may be a viable and safe option for deep sternal wound reconstruction.

Early onset of deep sternal wound infection after cardiac surgery is associated with decreased survival: A propensity weighted analysis

OBJECTIVES

To compare outcomes after the development of early (≤30 days) versus delayed (>30 days) deep sternal wound infection (DSWI) after cardiac surgery.

METHODS

Between 2005 and 2016, 64 patients were treated surgically for DSWI following cardiac surgery. Thirty-three developed early DSWI, while 31 developed late DSWI. The mean follow-up was 34.1 ± 32.3 months.

RESULTS

Survival for the entire cohort at 1, 3, and 5 years was 93.9%, 85.1%, and 80.8%, respectively. DSWI diagnosed early and attempted medical management was strongly associated with overall mortality (hazard ratio [HR], 25.0 and 9.9; 95% confidence intervals [CIs], 1.18-52.8 and 1.28-76.5; p-value .04 and .04, respectively). Survival was 88.1%, 77.0%, 70.6% and 100%, 94.0% and 94.0% at 1, 3, and 5 years in the early and late DSWI groups, respectively (log-rank = 0.074). Those diagnosed early were more likely to have a positive wound culture (odds ratio [OR], 0.06; 95% CI, 0.01-0.69; p = .024) and diagnosed late were more likely to be female (OR, 8.75; 95% CI, 2.0-38.4; p = .004) and require an urgent DSWI procedure (OR, 9.25; 95% CI, 1.86-45.9; p = .007). Both early diagnosis of DSWI and initial attempted medial management were strongly associated with mortality (HR, 7.48; 95% CI, 1.38-40.4; p = .019 and HR, 7.76; 95% CI, 1.67-35.9; p = .009, respectively).

CONCLUSIONS

Early aggressive surgical therapy for DSWI after cardiac surgery results in excellent outcomes. Those diagnosed with DSWI early and who have failed initial medical management have increased mortality.

[Treatment of postoperative anterior mediastinitis, sternal osteomyelitis in a patient with a novel coronavirus infection]

The incidence of mediastinitis after median sternotomy makes up 1-3%. This complication results prolonged hospital-stay, significant increase in treatment cost and high mortality (up to 75%). Severe COVID-19 pneumonia is often manifested by coughing, that impairs sternum stability after osteosynthesis. Moreover, concomitant leukopenia increases the risk of mediastinitis. Viral pneumonia and mediastinitis are complicated by respiratory failure and mutually potentiate the negative effect. Negative pressure wound therapy (NPWT) with combined antibiotic therapy ensures a favorable outcome even in patients with postoperative mediastinitis and osteomyelitis combined with viral pneumonia.

[Additional vascularization of the omental flap using mammary-gastroepiploic bypass grafting in the treatment of deep sternal wound infection]

Incidence of postoperative sternomediastinitis depends on various risk factors and makes up 8%. Surgical debridement with local management of the wound are used to achieve wound sterility. In some cases, sternectomy or subtotal sternal resection are performed for total sternal osteomyelitis with osteoporotic bone and multiple fractures. This procedure results an extensive bone defect. The final stage is anterior chest wall reconstruction. The most popular method is wound closure with autologous muscle or omental flaps. The authors describe a patient with sternomediastinitis who underwent staged treatment. At the final stage, subtotal sternectomy with simultaneous omentoplasty were performed. Additionally, mammary-gastroepiploic bypass grafting with right internal mammary artery and right gastroepiploic artery was carried out for additional vascularization of the omental flap. We found no similar surgery for sternomediastinitis in the literature. Long-term treatment outcome was followed-up (>50 months of relapse-free period and good quality of life).

Population pharmacokinetics of cefazolin before, during and after cardiopulmonary bypass in adult patients undergoing cardiac surgery

PURPOSE

The aims of the present study were to establish a population pharmacokinetic (PPK) model of cefazolin for adult patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) and to assess the probability of target attainment (PTA) for the prophylaxis of surgical site infection (SSI) using cefazolin.

METHODS

Adult patients who underwent cardiac surgery with CPB were enrolled in the prospective study. Blood samples for plasma cefazolin assay were collected, and total and unbound drug concentrations were measured and analysed using the nonlinear mixed-effects modelling (NONMEM) software considering saturable plasma protein binding. Using the PPK model, plasma unbound cefazolin concentration-time courses with current prophylaxis protocols were simulated, and the PTA for common SSI pathogens was estimated.

RESULTS

A total of 199 blood samples were obtained from 27 patients. A one-compartment model with first-order elimination plus an on/off CPB compartment best described the data. The population mean for systemic drug clearance (CL) was reduced and that for the volume of distribution (V) was increased during CPB compared with the pre-CPB values. CPB-induced hypoalbuminemia was associated with reduced maximum protein binding (B_max). The simulation studies suggested that the current dosing protocols are insufficient for attaining PTA > 0.9 throughout surgery against pathogens with minimum inhibitory concentrations (MICs) >8 mg/L. A new dosing protocol that achieves a PTA > 0.9 for pathogens with a MIC of 16 mg/L was proposed.

CONCLUSION

PPK modelling with simulation may be valuable for devising a cefazolin prophylaxis protocol for patients undergoing cardiac surgery with CPB.

Sternal Wound Complications: Results of Routine Use of Negative Pressure Wound Therapy

INTRODUCTION

Negative pressure wound therapy (NPWT) has significantly improved outcomes in individuals with superficial and deep sternal wound dehiscence (SWD). We report our experience with NPWT to evaluate factors influencing effectiveness, duration of treatment and postoperative hospital stay.

METHODS

We reviewed 92 patients with postoperative SWD following a median sternotomy. Patients were divided into 2 groups: those with a superficial SWD (Group 1; 72, 78%) and those with a deep SWD (Group 2; 20, 28%). Group 1 was further divided into 3 subgroups based on NPWT duration.

RESULTS

In both groups, none of the preoperative characteristics examined showed a significant association with longer NPWT duration. In Group 2, there was a trend for postoperative bleeding and neurological complications to be associated with longer treatment duration. In the entire series, staph infection resulted a weak predictor of NPWT duration. In each Group 1 subgroup and in Group 2, treatment days were compared with duration of hospitalization until discharge. Mean post-NPWT hospital stay was 6 days in subgroup 1, 12 days in subgroup 2 and 20 days in subgroup 3 (P<0.0001). At a median 3-year follow-up, there were 4 late deaths, none related to wound complications. No cases of SWD recurrence were observed.

CONCLUSION

Our results confirm the effectiveness of NPWT in SWD management, while excessive treatment duration might have a negative impact on the length of hospital stay. Further studies are needed to define an optimal use of NPWT protocol.

[Combined thoracoplasty using titanium mesh implant in patients with total sternal instability following postoperative sternomediastinitis]

OBJECTIVE

To analyze the results of chest wall reconstruction with titanium mesh implant in patients with total sternal instability following postoperative sternomediastinitis.

MATERIAL AND METHODS

There were 100 patients with total sternal instability for the period from January 2016 to December 2018. Median of age was 62 (58; 68) years. Male/female ratio was 82/18. All patients were treated in accordance with standardized protocol. Postoperative complications were assessed using Clavien-Dindo scale. Staged surgical treatment including one or more debridement procedures before the final thoracoplasty was performed in 62 (62%) out of 100 patients. Aseptic sternal instability was observed in 38 patients.

RESULTS

Follow-up period ranged from 3 weeks to 35 months after the final thoracoplasty. Complicated postoperative period occurred in 15 (15%) out of 100 patients (95% CI 9.3-23.3). One patient died in 9 days after surgery from acute heart failure. Complications without need for redo surgery, postoperative wound suppuration and seroma were noted in 3 patients. Redo surgery was required in 11 patients due to postoperative wound suppuration, eventration after thoracoomentoplasty, intermuscular hematoma and delayed divergence of major pectoral muscles. Removal of mesh implant was performed in 1 out of 100 patient (95% CI 0.2-5.5) in 7 days after surgery due to suppuration. There was no recurrent sternal instability within 30 days.

CONCLUSION

Anterior chest wall reconstruction using titanium mesh implant is an effective and safe procedure in patients with postoperative sternal instability following postoperative sternomediastinitis.

Effects of cardiopulmonary bypass on the disposition of cefazolin in patients undergoing cardiothoracic surgery

The aim of the study was to evaluate the disposition of plasma unbound cefazolin in patients undergoing cardiothoracic surgery with cardiopulmonary bypass (CPB). Adult patients undergoing cardiothoracic surgery with CPB were enrolled in the study. Cefazolin sodium was given intravenously before skin incision (1 g) and at the beginning of CPB (2 g). Thereafter, an additional dose (1 g) was given every 4 hours. Seven to ten blood samples were collected before and during surgery. Plasma total and unbound (ultrafiltrated) cefazolin concentrations were analyzed using an HPLC-UV method. Plasma protein binding was analyzed with the Langmuir model. Twenty-seven patients (aged 70 ± 12 years, body weight 62 ± 12 kg, mean ± SD) with GFR >30 mL min-1 completed the study. There was a significant (P < 0.001) increase in median plasma unbound fraction of cefazolin from 21% before skin incision to 45% during CPB (P < 0.001), which was accompanied by a significant (P < 0.001) reduction in median plasma albumin concentration from 36 to 27 g L-1. Plasma concentrations of unbound cefazolin exceeded the assumed target thresholds of 2 μg mL-1 in all samples and of 8 μg mL-1 in all but one of 199 samples. The increased plasma unbound fraction of cefazolin would be attributable to dilutional reduction of serum albumin at the beginning of CPB and to saturable plasma protein binding of cefazolin. These data reveal CPB may alter the plasma protein binding and possibly distribution of cefazolin. Further studies are warranted to reappraise the protocol of antimicrobial prophylaxis with cefazolin in patients undergoing surgery with CPB.

From open packing to negative wound pressure therapy: A critical overview of deep sternal wound infection treatment strategies after cardiac surgery

Deep sternal wound infection is a challenging aspect of modern cardiac surgery. The considerable mortality rate, devastating morbidity and, negative impact on long-term survival has driven cardiac and plastic surgeons to seek a more advantageous treatment solution. This review summarizes progress in the field of deep sternal wound infection treatment after cardiac surgery. Emphasis is placed on outcomes analysis of contemporary treatment strategy based on negative pressure wound therapy followed by sternotomy wound reconstruction, and its comparison with conventional treatment modalities used afore. Furthermore, complications and drawbacks of treatment strategies are critically evaluated to outline current options for successfully managing this life-threatening complication following cardiac surgery.

Effect of negative pressure wound therapy followed by tissue flaps for deep sternal wound infection after cardiovascular surgery: propensity score matching analysis

OBJECTIVES

Deep sternal wound infection (DSWI) after cardiovascular surgery via median sternotomy remains a severe complication associated with a drastic decrease in the quality of life. We assessed the risk factors for in-hospital death caused by DSWI and the available treatments for DSWI.

METHODS

Between January 1991 and August 2015, we retrospectively reviewed 73 patients (51 males and 22 females, mean age 67.5 ± 10.3 years) who developed DSWI after cardiovascular surgery via median sternotomy. Pathogenic bacteria mainly comprised methicillin-resistant Staphylococcus aureus (MRSA) (49.3%). Fifteen patients (20.5%) died in hospital with DSWI. Treatment of DSWI consisted of open daily irrigation (up to 2006) or negative pressure wound therapy (NPWT) (2007 onwards), followed by primary closure or reconstruction of tissue flaps. We assessed the risk factors for in-hospital mortality from DSWI by comparing data from the 15 patients who died and the 58 survivors using propensity score matching analysis of the treatments used for DSWI.

RESULTS

Univariate analysis identified age, use of intra-aortic balloon pumping, prolonged mechanical ventilation, tracheotomy, prolonged intensive care unit stay, postoperative low output syndrome, postoperative myocardial infarction, postoperative renal failure, postoperative use of haemodialysis, postoperative pneumonia, postoperative cerebral disorder, MRSA infection, NPWT and tissue flaps as being associated with in-hospital mortality (P < 0.05). Multivariate analysis identified NPWT (odds ratio, 0.062; 95% confidence interval, 0.004-0.897; P = 0.041) and tissue flaps (odds ratio, 0.022; 95% confidence interval, 0.000-0.960; P = 0.048) as independently associated with reduced in-hospital mortality after DSWI. On comparing 22 patients receiving NPWT with 22 not on NPWT using propensity score matching, patients on NPWT had significantly lower in-hospital mortality than those without NPWT (NPWT vs non-NPWT, 5 vs 36%, P = 0.021). In DSWI infected by MRSA, NPWT significantly reduced the in-hospital mortality caused by DSWI (NPWT vs non-NPWT, 0 vs 52%, P = 0.003).

CONCLUSIONS

NPWT and tissue flaps may be favourable factors associated with reduced in-hospital mortality attributable to DSWI. NPWT as a bridge therapy to tissue flaps may play a major role in treating DSWI and improve the prognosis for patients with MRSA-infected DSWI.

Defining post-sternotomy mediastinitis for clinical evidence-based studies

Background

Considerable advances have already been made in the treatment of deep thoracic wound infections following a median sternotomy for cardiac surgery. Further improvement in diagnosis, treatment, and outcome will require a targeted approach by multidisciplinary teams. Clear communication and synergy between the various clinical and supportive disciplines would assist in removing the last barriers to standardized evidence-based studies and the development of improved evidence-based guidelines.

Methods

An extensive literature search without language restrictions was carried out on PubMed (Medline), EMBASE, and Web of Science, covering the period 1988 to week 16, 2014, and a manual search of the reference lists was performed regarding all possible definitions and classifications of post-sternotomy mediastinitis. Two hundred and eighteen papers describing post-sternotomy infections in a multitude of terms were identified, and the strengths and weaknesses of the most popular definitions and terms relating specifically to post-sternotomy infections were examined.

Results

This study revealed that clinicians use a multitude of terms to describe post-sternotomy infections without defining the condition under treatment. Occasionally, older epidemiological (surveillance) definitions were used. It also shows that supportive disciplines have their own definitions, or interpretations of existing definitions, to describe these infections.

Conclusion

The outcome of this study is that clinicians have adopted no single definition, which is essential for further improvement for evidence-based studies. We suggest that it is possible to adopt a single term for thoracic infection after a sternotomy (and only sternotomy), and propose a clinical definition for this purpose.

Deep sternal wound infection after cardiac surgery: Evidences and controversies

Despite many advances in prevention and perioperative care, deep sternal wound infection (DSWI) remains a pressing concern in cardiac surgery, with a still relevant incidence and with a considerable impact on in-hospital mortality and also on mid- and long-term survival. The permanent high impact of this complication is partially related to the increasing proportion of patients at high-risk for infection, as well as to the many patient and surgical risk factors involved in the pathogenesis of DSWI. The prophylactic antibiotic therapy is one of the most important tools in the prevention of DSWI. However, the choice of antibiotic, the dose, the duration, the adequate levels in serum and tissue, and the timing of antimicrobial prophylaxis are still controversial. The treatment of DSWI ranges from surgical revision with primary closure to surgical revision with open dressings or closed irrigation, from reconstruction with soft tissue flaps to negative pressure wound therapy (NPWT). However, to date, there have been no accepted recommendations regarding the best management of DSWI. Emerging evidence in the literature has validated the efficacy and safety of NPWT either as a single-line therapy, or as a “bridge” prior to final surgical closure. In conclusion, the careful control of patient and surgical risk factors - when possible, the proper antimicrobial prophylaxis, and the choice of validated techniques of treatment could contribute to keep DSWIs at a minimal rate.

Therapeutic Outcomes of Pectoralis Major Muscle Turnover Flap in Mediastinitis

Background

This study aimed to evaluate the therapeutic results and safety of pectoralis major muscle turnover flaps in the treatment of mediastinitis after coronary artery bypass grafting (CABG) procedures.

Methods

Data regarding 33 patients with post-CABG deep sternal wound infections (DSWIs) who underwent pectoralis major muscle turnover flap procedures in the Emam Reza and Ghaem Hospitals of Mashhad, Iran were reviewed in this study. For each patient, age, sex, hospital stay duration, remission, recurrence, and associated morbidity and mortality were evaluated.

Results

Of the 2,447 CABG procedures that were carried out during the time period encompassed by our study, DSWIs occurred in 61 patients (2.5%). Of these 61 patients, 33 patients (nine females [27.3%] and 24 males [72.7%]) with an average age of 63±4.54 years underwent pectoralis major muscle turnover flap placement. Symptoms of infection mainly occurred within the first 10 days after surgery (mean, 10.24±13.62 days). The most common risk factor for DSWIs was obesity (n=16, 48.4%) followed by diabetes mellitus (n=13, 39.4%). Bilateral and unilateral pectoralis major muscle turnover flaps were performed in 20 patients (60.6%) and 13 patients (39.4%), respectively. Complete remission was achieved in 25 patients (75.7%), with no recurrence in the follow-up period. Four patients (12.1%) needed reoperation. The mean hospitalization time was 11.69±6.516 days. Four patients (12.1%) died during the course of the study: three due to the postoperative complication of respiratory failure and one due to pulmonary thromboembolism.

Conclusion

Pectoralis major muscle turnover flaps are an optimal technique in the treatment of post-CABG mediastinitis. In addition to leading to favorable therapeutic results, this flap is associated with minimal morbidity and mortality, as well as a short hospitalization time.

A simple protocol for the management of deep sternal surgical site infection: a retrospective study of twenty-five cases

BACKGROUND

Deep sternal incisional surgical site infection is a serious and potentially life-threatening complication after open heart surgery. Although a rare post-operative complication, the rates of post-operative morbidity and mortality are greater in patients who develop a deep sternal incisional surgical site infection than in those who do not.

METHODS

We evaluated retrospectively the results of patients who developed a deep sternal incisional surgical site infection who were treated with either a pectoralis major flap or delayed primary closure after previous negative-pressure wound therapy (NWPT). From July 2007 to July 2012, 25 patients had a deep sternal incisional surgical site infection after open heart surgery in the Departments of Plastic Surgery and Cardiac Surgery of the Tri-Service General Hospital Medical Center. Sternal refixation was not performed in our patients.

RESULTS

In 15 patients, a unilateral or bilateral pectoralis major advancement flap with a myocutaneous or muscle flap was used. In seven patients, delayed primary closure was performed after NPWT. One patient received a rectus abdominis myocutaneous flap and another received a free anterior lateral thigh flap. One patient died after developing nosocomial pneumonia with severe sepsis after debridement.

CONCLUSIONS

In our series, no patient required sternal re-fixation. Our findings suggest that delayed primary closure and use of a unilateral or bilateral pectoralis major flap following NPWT for a deep sternal incisional surgical site infection are simple and quick methods for managing such difficult surgical incisions even if the deep sternal surgical site infection is located in the lower one-third of the sternum.

Poststernotomy mediastinitis: a classification to initiate and evaluate reconstructive management based on evidence from a structured review

Early recognition and, where possible, avoidance of risk factors that contribute to the development of poststernotomy mediastinitis (PSM) form the basis for successful prevention. Once the presence of PSM is diagnosed, the known risk factors have been shown to have limited influence on management decisions. Evidence-based knowledge on treatment decisions, which include the extent and type of surgical intervention (other than debridement), timing and others is available but has not yet been incorporated into a classification on management decisions regarding PSM. Ours is a first attempt at developing a classification system for management of PSM, taking the various evidence-based reconstructive options into consideration. The classification is simple to introduce (there are four Types) and relies on the careful establishment of two variables (sternal stability and sternal bone viability and stock) prior to deciding on the best available reconstructive option. It should allow better insight into why treatment decisions fail or have to be altered and will allow better comparison of treatment outcomes between various institutions.

Risk factors for complications after reconstructive surgery for sternal wound infection

Background

Although the utility of flaps for the treatment of sternal wound infections following median sternotomy has been reported for 30 years, there have been few reports on the risk factors for complications after reconstruction. The objective of this investigation was to identify factors related to complications after the reconstruction of sternal wound infections.

Methods

A retrospective analysis of 74 patients with reconstructive surgery after sternal wound infection over a 5-year period was performed. Clinical data including age, sex, body mass index (BMI), comorbidities, bacterial culture, previous cardiac surgery, wound depth, mortality rate, type of reconstructive procedure, and complication rate were collected.

Results

The patients' BMI ranged from 15.2 to 33.6 kg/m² (mean, 23.1±3.74 kg/m²). Wound closure complications after reconstructive surgery were observed in 36.5% of the cases. The mortality rate was 2.7%. Diabetes mellitus significantly affected the rate of wound closure complications (P=0.041). A significant difference in the number of complications was seen between Staphylococcus aureus (S. aureus) and coagulase-negative Staphylococci (P=0.011). There was a correlation between harvesting of the internal thoracic artery and postoperative complications (P=0.048). The complication rates of the pectoralis major flap, rectus abdominis flap, omentum flap, a combination of pectoralis major flap and rectus abdominis flap, and direct closure were 23.3%, 33.3%, 100%, 37.5%, and 35.7%, respectively.

Conclusions

Diabetes mellitus, S. aureus, harvesting of the internal thoracic artery, and omentum flap were significant factors for complications after reconstruction. The omentum flap volume may be related to the complications associated with the omentum flap transfer in the present study.

Methicillin-resistant Staphylococcus aureus infection: an independent risk factor for mortality in patients with poststernotomy mediastinitis

OBJECTIVE

The mortality rate of patients with poststernotomy mediastinitis remains very high. The aim of this study was to identify the risk factors associated with mortality in these patients.

SUBJECTS AND METHODS

Surveillance of sternal surgical-site infections including mediastinitis was carried out for adult patients undergoing a sternotomy between 2004 and 2012. Criteria from the US Centers for Disease Control and Prevention were used to make the diagnosis. All data on patients with a diagnosis of mediastinitis who were included in the study and on mortality risk factors were obtained from the hospital database and then analyzed using SPPS 16.0 for Windows.

RESULTS

Of the 19,767 patients undergoing open heart surgery, 117 (0.39%) had poststernotomy mediastinitis; 32% of these 117 died. The independent risk factors for mortality were methicillin-resistant Staphylococcus aureus (MRSA) [odds ratio (OR) 12.11 and 95% confidence interval (CI) 3.15-46.47], intensive-care unit stays >48 h after the first operation (OR 11.21 and 95% CI 3.24-38.84) and surgery that included valve replacement (OR 6.2 and 95% CI 1.44-27.13). The mortality rate decreased significantly, dropping from 38% (34/89) between 2004 and 2008 to 14% (4/28) between 2009 and 2012 (p = 0.018).

CONCLUSION

In this study, elimination of MRSA from the hospital setting decreased the rate of mortality in patients with poststernotomy mediastinitis.

Failure of secondary wound closure after sternal wound infection following failed initial operative treatment: causes and treatment

BACKGROUND

Patients transferred to Plastic Surgery Departments for sternum osteomyelitis have a high morbidity of about 3%. Despite several known options for sternal wound coverage and salvage operations, wound dehiscence or wound necrosis can occur, increasing patient morbidity.

PATIENTS AND METHODS

One hundred thirty-five patients admitted between January 2007 and December 2010 were evaluated in a retrospective study for wound dehiscence after salvage wound coverage at our institution. Various flaps were applied, such as pectoralis major myocutaneous pedicled flaps, pectoralis major muscle pedicled flaps, latissimus dorsi pedicled flaps, greater omental flaps, and vertical rectus abdominis muscle and transverse rectus abdominis muscle flaps. Inclusion criteria were sternal wound infection, bacterial wound infection, previous wound debridement outside our institution, vacuum-assisted closure device wound treatment at our institution, and secondary flap closure of the sternal defect at our institution. A multivariate regression analysis was performed.

RESULTS

One hundred thirty patients met the inclusion criteria. In all patients, bacterial wound colonization was shown. Forty patients showed wound dehiscence after closure at our institution. Reasons for wound dehiscence were attributed to wound size, >4 different species of bacteria colonizing the wound, gram-negative bacteria, Candida albicans, intensive care unit stay, and female gender. Interestingly, wound dehiscence was not significant correlated to obesity, smoking, atherosclerosis, renal insufficiency or type of closure influenced significantly, or necrosis.

CONCLUSIONS

Female patients after CABG, with large sternal wounds infected with gram-negative bacteria and candida, have an 85% risk of wound dehiscence after flap coverage for sternal wound infection.

Impact of vacuum-assisted closure (VAC) therapy on clinical outcomes of patients with sternal wound infections: a meta-analysis of non-randomized studies

Objective

To examine the impact of VAC therapy on mortality of patients with sternal wound infections after cardiothoracic surgery.

Summary Background Data

Controversial results regarding mortality of patients with sternal wound infections were published.

Methods

We performed a systematic search in PubMed and Scopus. Mortality was the primary outcome of the meta-analysis. Recurrences, complications and length of stay were secondary outcomes.

Results

Twenty-two retrospective studies including 2467 patients were eligible for inclusion. Patients treated with VAC had significantly lower mortality compared to those treated without VAC [2233 patients, RR = 0.40, (95% CI 0.28, 0.57)]. This finding was consistent regardless of the study design, the exclusion of studies with positive findings, the criteria for establishment of the compared groups, the time of mortality assessment or the type of infections under study, provided that adequate data was available. VAC therapy was associated with fewer recurrences (RR = 0.34, 95% CI: 0.19–0.59). The meta-analysis did not show any difference in the length of stay (RR = −2.25, 95% CI: −7.52–3.02).

Conclusions

VAC therapy was associated with lower mortality than other surgical techniques in retrospective cohorts of patients with DSWIs following cardiothoracic surgery.