Infected median sternotomy wound. Successful treatment by muscle flaps

An Unusual Case of Sternal Osteomyelitis and Purulent Mediastinitis After a Traumatic Sternal Body Fracture

A 67-year-old female presented to the emergency department after falling on her chest. On initial presentation, her chest wall was tender to palpation with mild overlying ecchymosis. Initial imaging demonstrated a sternal body fracture with minimal retrosternal hematoma. On hospital day four, a fluctuant mass was appreciated over her sternum. A repeat CT scan demonstrated an abscess collection anterior and posterior to her sternum with underlying subcutaneous emphysema. The patient was taken to the operating room for incision and drainage with sternal body debridement. Pathology resulted in acute and chronic osteomyelitis and fluid culture with methicillin-sensitive Staphylococcus aureus (MSSA). Following infectious process resolution, the incision was closed with bilateral pectoralis advancement flaps. This case represents a rare complication of a relatively common traumatic injury, namely, a sternal fracture. In this scenario, due to the high mortality associated with mediastinitis, an immediate intervention and a multidisciplinary approach are cornerstones for optimal outcomes.

[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.

[The split turnover pectoralis muscle flap: an easy and safe method for sternal wound coverage]

The conventional pectoralis muscle flap is well known for the reconstruction of sternal defects after deep sternal wound infection. The pectoralis muscle flap can be harvested as an advancement flap based on the thoracoacromial artery, or it can be harvested as a turnover flap based on intercostal perforators of the internal thoracic artery. A disadvantage of the advancement flap can be seen in its limited reach, especially for covering the lower third of the sternum. The turnover flap is well suited for coverage of the lower and middle sternal third, but then lacks the length for coverage of the cranial third. The authors describe a new method for splitting up the pectoralis turnover muscle flap along its muscle fibres in order to gain additional length. Between 2017 and 2022, we treated 12 patients with this method. Total wound coverage and closure have been achieved in all 12 patients. Thus, the split turnover pectoralis flap is a safe and effective method for sternal wound treatment.

Extensive suprasternal dehiscence reconstruction with NPWT and advancement flaps following cardiac surgery

Treatment of suprasternal wound infection (SSWI) following cardiac surgery is not a clearly developed procedure. We report our female patient's secondary SSWI treatment following bypass surgery. An obese female patient with unstable angina underwent an urgent, uneventful off-pump coronary artery bypass operation. An SSWI appeared within a week. After negative pressure wound therapy (NPWT), the sternum was rewired. In the previously irradiated territory of the left breast necrosis formed, a plastic surgeon reconstructed a defect. This procedure failed NPWT was restarted again, and a secondary reconstructive plastic surgery intervention was necessary. Despite extensive tissue mobilization, the central part of the reconstructive area necrotized, and we had to cover it with a split thickness skin mash graft. The irradiation therapy increases the incidence of suprasternal and/or sternal infection. It was possible to manage large soft tissue defects with bilateral and rotational advancement flaps.

The role of negative pressure wound therapy in the treatment of poststernotomy mediastinitis in Asians: A single-center, retrospective cohort study

Introduction

Poststernotomy mediastinitis (PSM) is a critical and life-threatening complication that can arise after cardiac surgery. The aim of this study was to evaluate and compare the outcomes of negative pressure wound therapy (NPWT) and conventional methods in the management of mediastinitis following heart surgery with a focus on Asian populations.

Methods

For this retrospective study, we included and evaluated a total of 34 patients who had undergone cardiac operations between January 2011 and September 2021 and developed PSM. The patients were divided into two groups, the NPWT group (n = 16, 47.1%) and the conventional treatment group (n = 18, 52.9%), and compared.

Results

The two groups showed no significant differences in terms of patient characteristics, PSM wound classification based on the El Oakley classification, and wound closure methods, but there was a higher incidence of diabetes mellitus in the NPWT group. With regard to mediastinal cultures, a higher prevalence of Staphylococcus epidermidis was observed in the NPWT group. However, we found no significant differences between the two groups regarding the time interval from diagnosis to wound closure, hospitalization duration, and re-exploration rate. Notably, the NPWT group exhibited a significantly higher in-hospital mortality rate than the conventional treatment group (p = 0.024).

Conclusions

Our findings suggest that the use of NPWT might not lead to improved medical outcomes for patients with PSM when compared to conventional treatment methods. As a result, it becomes imperative to exercise great care when choosing patients for NPWT. To obtain more definitive and conclusive results and identify the most appropriate cases for NPWT, conducting larger randomized clinical trials is necessary.

Free Flaps in Sternal Osteomyelitis After Median Sternotomy: A Center's 12-Year Experience

BACKGROUND

 Adequate treatment of deep sternal wound infections (DSWIs) after open thoracic surgery still presents a major challenge. This study retrospectively analyzes the results of a single center's 12-year experience in treating DSWI, with special emphasis on free flap reconstruction.

METHODS

 In this single-center, retrospective study, all patients admitted with the diagnosis of DSWI after open thoracic surgery between 2009 and 2020 were included. A comparative analysis was performed between: (1) pedicled versus free flaps, (2) the center's two workhorse flaps-the pedicled latissimus dorsi (pLD) versus free anterolateral thigh (fALT) flaps, as well as (3) myocutaneous (MC) versus fasciocutaneous (FC) flaps. Primary endpoints were length of hospital stay (LOS) after reconstruction and in-hospital mortality.

RESULTS

 Of a total of 165 patients included, 152 underwent DSWI defect reconstruction with a total of 12 different reconstruction methods. Although the defect size was larger in patients who underwent free flap coverage, and the risk profile in the fALT and FC flap groups was higher, the LOS after reconstruction (in days) did not differ significantly between the groups (pedicled vs. free flaps: 23 vs. 28, p > 0.05; pLD vs. fALT: 24.5 vs. 26, p > 0.05; MC vs. FC flaps: 23 vs. 26, p > 0.05). Also, no significant differences were found in terms of in-hospital mortality when comparing the groups (pedicled vs. free flaps: 11.2 vs. 17.4%, p > 0.05; pLD vs. fALT: 11.5 vs. 12.5%, p > 0.05; MC vs. FC flaps: 12.9 vs. 12.5%, p > 0.05).

CONCLUSION

 With proper patient selection, free tissue transfer is a valuable alternative in the treatment of sternal dehiscence after a DSWI. Furthermore, our data demonstrate that MC flaps are not necessarily superior to FC flaps in the reconstruction of sternal osteomyelitis defects.

Comparison between Vacuum-Assisted Closure Technique and Conventional Approach in Patients with Mediastinitis After Isolated Coronary Artery Bypass Graft Surgery

INTRODUCTION

Median sternotomy is the most preferred approach in heart surgery. Post-sternotomy mediastinitis is a catastrophic and potentially life-threatening complication with an incidence rate of 0.15% to 5%, and its overall mortality rate reaches 47%. In this study, we aimed to compare the results of vacuum-assisted closure technique and the conventional methods on the management of mediastinitis following isolated coronary artery bypass graft surgery.

METHODS

Between February 2001 and July 2013, 32,106 patients who underwent cardiac operations were evaluated retrospectively. One hundred and fourteen patients who developed post-sternotomy mediastinitis were included in this study. The patients were divided into two groups and compared - vacuum-assisted closure group (n=52, 45.6%) and conventional treatment group (n=62, 54.4%).

RESULTS

There were no differences between the two groups according to the patients' characteristics, surgical data, and mediastinal cultures. However, we found that total treatment duration for post-sternotomy mediastinitis, time interval from diagnosis to negative culture, hospitalization time, and in-hospital mortality were statistically significantly lower in the vacuum-assisted closure group than in the conventional treatment group (P<0.001, P<0.001, P<0.001, and P=0.03, respectively).

CONCLUSION

This study demonstrates that the vacuum-assisted closure technique improves the medical outcome of patients with post-sternotomy mediastinitis compared with the conventional treatment. The vacuum-assisted closure is a safe and more effective treatment modality for patients with post-sternotomy mediastinitis after cardiac surgery with reasonable morbidity and mortality.

Optimal Timing of Multidisciplinary Management of Sternal Wound Complications

Background

Sternal wound complications after median sternotomy increase morbidity and mortality, and plastic and reconstructive surgery is often consulted to provide closure with flap reconstruction. In this study, we investigated how the timing of plastic surgery involvement may influence outcomes in this setting.

Methods

We performed a retrospective review of patients with sternal wound complications cared for at our institution during a 10-year period. Patients were stratified into quartiles based on time from detected complication to plastic surgery consultation. Primary outcome variables included morbidity (postoperative complications and reoperation) and all-cause mortality at 1 year. Univariable followed by multivariable logistic regression was performed to characterize risk factors for these adverse outcomes.

Results

A total of 188 patients composed the study population. The time to plastic surgery consultation quartiles were as follows: immediate, 0 to 1 days (n = 46); early, 2 to 5 days (n = 50); delayed, 6 to 14 days (n = 42); and late, >14 days (n = 50). Patient demographics, comorbidities, and reconstructive characteristics did not differ across groups. Increased time to plastic surgery consultation was associated with sternal wound reoperations (P = .026), 1-year mortality (P = .008), hematoma (P = .044), and sternal dehiscence recurrence (P = .019). Multivariable regression demonstrated that increased time to plastic surgery consultation was associated with increased sternal wound reoperations (odds ratio [OR], 1.1; P = .041), sternal wound recurrence (OR, 1.5; P = .018), and mortality (OR, 1.3; P = .037).

Conclusions

Early involvement of plastic surgery in treating sternal wounds is significantly associated with a reduction in mortality, recurrence of sternal dehiscence, and reoperation. Successful treatment of these challenging complications requires multidisciplinary collaboration, and prompt plastic surgery consultation is recommended.

Combined pectoralis and rectus abdominis flaps are associated with improved outcomes in sternal reconstruction

BACKGROUND

Mortality increases nearly 5-fold in the approximately 5% of patients who develop sternal wound complications after cardiothoracic surgery. Flap-based reconstruction can improve outcomes by providing well-vascularized soft tissue for potential space obliteration, antibiotic delivery, and wound coverage; however, reoperation and readmission rates remain high. This study used the high case volume at a tertiary referral center and a diverse range of reconstructive approaches to compare various types of flap reconstruction. Combined (pectoralis and rectus abdominis) flap reconstruction is hypothesized to decrease sternal wound complication-related adverse outcomes.

METHODS

A retrospective cohort study of consecutive adult patients treated for cardiothoracic surgery sternal wound complications between 2008 and 2018 was performed. Patient demographics, comorbidities, wound characteristics, surgical parameters, and perioperative data were collected. Multivariable regression modeling with stepwise forward selection was used to characterize predictive factors for sternal wound-related readmissions and reoperations.

RESULTS

In total, 215 patients were assessed for sternal wound reconstruction. Patient mortality at 1 year was 12.4%. Flap selection was significantly associated with sternal wound-related readmissions (P = .017) and reoperations (P = .014). Multivariate regression demonstrated rectus abdominis flap reconstruction independently predicted increased readmissions (odds ratio 3.4, P = .008) and reoperations (odds ratio 2.9, P = .038). Combined pectoralis and rectus abdominis flap reconstruction independently predicted decreased readmissions overall (odds ratio 0.4, P = .031) and in the deep sternal wound subgroup (odds ratio 0.1, P = .033).

CONCLUSION

Although few factors can be modified in this complex highly comorbid population with a challenging and rare surgical problem, consideration of a more surgically aggressive multiflap reconstructive approach may be justified to improve outcomes.

Evaluating the effectiveness of using negative pressure wound therapy in the preservation of the infected prosthetic aortic graft

BACKGROUND

Infected deep sternal infection due to an associated infection of the prosthetic aortic graft is a devastating condition. Standard management requires the removal of the graft and substituting it with a new one. Often, removal of the prosthetic graft is close to impossible. Negative pressure wound therapy is currently the treatment of choice for patients with deep sternal infection. However, its use in deep sternal infection with exposed infected prosthetic aortic graft has not been well described.

METHODS

Eight patients were included in this study. All had type A aortic dissection of the ascending aorta and/or aortic arch.

RESULTS

There were 7 men and 1 woman. The median age was 53 years old (range 33-81 years old). The median number of days from the initial aortic operation to the diagnosis of infection was 20 days (range 14-52). The median length of stay in the intensive care unit was 17 days (range 6-338 days). The median time interval from the initial debridement to reconstruction was 20 days (range 6-43 days). The median number of times negative pressure wound therapy was changed was 4 (range 2-9). The most common flap used for reconstruction was the pectoralis major musculocutaneous flap in 7 patients, a free antero-lateral thigh flap in 1 patient, and pedicled omental flap in combination with pectoralis major musculocutaneous flap in 1 patient. One patient had persistent recurrent infection of the graft despite negative pressure wound therapy and flap reconstruction. The median length of follow-up was 38.5 months (range 4-120 months).

CONCLUSION

This small study suggests that negative pressure wound therapy could be used successfully for the management of deep sternal infection due to infected prosthetic aortic grafts. In most cases, it eliminated the need to replace the infected prosthetic aortic graft in high-risk patients.

Deep sternal wound infection and pectoralis major muscle flap reconstruction: A single-center 20-year retrospective study

Background

One of the most drastic complications of median sternal incision is deep sternal wound infection (DSWI), as it can lead to prolonged hospitalization, increased expected costs, re-entry into the ICU and even reoperation. Since the pectoralis major muscle flap (PMMF) technique was proposed in the 1980s, it has been widely used for sternal reconstruction after debridement. Although numerous studies on DSWI have been conducted over the years, the literature on DSWI in Chinese population remains limited. The purpose of this study was to investigate the clinical characteristics of DSWI in patients and the clinical effect of the PMMF at our institution.

Methods

This study retrospectively analyzed all 14,250 consecutive patients who underwent cardiac surgery in the Department of Cardiothoracic Surgery of Drum Tower Hospital from 2001 to 2020. Ultimately, 134 patients were diagnosed with DSWI.,31 of whom had recently undergone radical debridement and transposition of the PMMF in the cardiothoracic surgery or burns and plastic surgery departments because of DSWIs, while the remaining patients had undergone conservative treatment or other methods of dressing debridement.

Results

In total, 9,824 patients were enrolled in the study between 2001 and 2020, of whom 134 met the DSWI criteria and 9690 served as controls. Body mass index (OR = 1.08; P = 0.02; 95% CI, 1.01∼1.16) and repeat sternotomy (OR = 5.93; P &lt; 0.01; 95% CI, 2.88∼12.25) were important risk factors for DSWI. Of the 134 patients with DSWI, 31 underwent the PMMF technique, and the remaining 103 served as controls. There were significant differences in coronary artery bypass grafting (CABG) (P &lt; 0.01), valve replacement (P = 0.04) and repeat sternotomy (P &lt; 0.01) between the case group and the control group. The postoperative extubation time (P &lt; 0.001), ICU time (P &lt; 0.001), total hospitalization time (P &lt; 0.001) and postoperative hospitalization time (P &lt; 0.001) in the PMMF group were significantly lower than those in the control group. The results of multivariate regression analysis showed that PMMF surgery was an important protective factor for the postoperative survival of DSWI patients (OR = 0.12; P = 0.04; 95% CI, 0.01∼0.90).

Conclusions

Staphylococcus aureus was the most common bacteria causing DSWI, which was associated with BMI and reoperation, and can be validly treated with PMMF.

Efficacy and safety of pectoralis muscle flap combined rectus abdominis muscle sheath fasciocutaneous flap for reconstruction of sternal infection

Few studies have assessed the efficacy and safety of reconstruction of sternal infection using a pectoralis muscle flap combined with a rectus abdominis muscle (RAM) sheath fasciocutaneous flap. We report here our experience with this procedure to reconstruct the sternal defect in patients (n = 46) with a deep sternal wound infection (DSWI) after cardiac surgery. After wound reconstruction, the proportion of prolonged mechanical ventilation use and intensive care unit (ICU) stay were 17.4% (n = 8) and 21.7% (n = 10), respectively. The 30‐day all‐cause mortality was 15.2%; recurrence rate was 17.4%; postoperative complications were 15.2%; and median hospital stay was 31 (0‐157) days. Multivariate logistic regression analysis revealed that hypertension (β = 21.32, 95%CI 4.955‐37.68, P = .014), drainage‐tube use (β = 0.944, 95%CI 0.273‐1.614, P = .008), and prolonged intensive care unit stay (β = 53.65, 95%CI 31.353‐75.938, P < .001) were significantly correlated with hospital stay. In conclusion, a procedure including surgical debridement, sternal reconstruction with bilateral PM and RAM sheath flap, long‐term antibiotics, and adequate drainage is a beneficial technique in the reconstruction of deep sternal wound infection after cardiac surgery. Duration of drainage tube use may be as an index for a hospital stay or wound healing.

Adhesion of bioactive glass-based adhesive to bone

Understanding the failure modes and the fracture resistance is critical in evaluating the performance of an adhesive for sternal fixation. In this paper, a fracture mechanics testing methodology was used to assess the adhesion of a bioactive glass-based adhesive to bovine bone in terms of a measured mode I critical strain energy release rate (G_IC). Reinforced double cantilever beam (DCB) samples were observed to produce repeatable values of G_IC. The measured G_IC was found to increase significantly from 5.41 to 12.60 J/m² with an increase in adhesive thickness from 390 to 990 μm because of the constraint from the two adherends regulating the plastic zone size ahead of the crack. The specimens failed cohesively in all cases demonstrating that there was good adhesion to bone, a condition necessary to restrict micromotion and thus provide rigid sternal fixation when used along with sternal wires. It was also found that when the bone was flooded with liquid during adhesive application a much lower G_IC of between 0.69 and 1.15 J/m² was measured. Overall, the results demonstrate that the fracture mechanics approach can be used to provide a quantitative measure of the adhesion of the bioactive glass-based adhesive to the bone and that the adhesive should only be applied to clean bone in a dry environment.

Partition of Pectoralis Major Musculocutaneous Flap as a Salvage Procedure for Simultaneous Coverage of the Exposed Carotid Artery and Reconstruction of Cervical Esophagus

BACKGROUND

In advanced pharyngoesophageal cancer patients, a critical event is represented by the failure of primary reconstruction with exposure of the carotid artery and partial or total defect of the cervical esophagus. For these high-risk patients, a partitioned pectoralis major musculocutaneous (PMMC) flap can prevent carotid blowout and provide skin for simultaneous esophageal reconstruction.

METHODS

Twenty-six patients needing pharyngoesophageal reconstruction together with coverage of carotid artery exposure were included in this retrospective case series. The patients were treated with a partitioned PMMC flap, based on the branching pattern of the pectoral branch of the thoracoacromial artery and the perforators of the pectoralis major muscle, to simultaneously reconstruct the defect and provide coverage for the carotid artery.

RESULTS

In 25 patients, the partitioned PMMC flap reconstructions resulted in complete wound healing without occurrence of carotid blowout syndrome or fistula formation. Minor complications as partial flap necrosis (7.7%) and strictures formation (7.7%) were recorded but did not compromise reconstruction. Twenty-two patients were able to adopt a semisolid diet, and 4 had recurrence of cancer.

CONCLUSIONS

The partitioned PMMC flap reconstruction represents a useful salvage solution to simultaneously restore the continuity of the alimentary tract and provide reliable coverage for the exposed carotid artery.

Early to midterm survival of patients with deep sternal wound infection managed with laparoscopically harvested omentum

OBJECTIVE

The optimal management of deep sternal wound infection (DWSI) remains controversial. Our objective was to evaluate outcomes of patients with DSWI managed with transposition of laparoscopically harvested omentum (LHO).

METHODS

Between 2000 and 2020, a total of 38,623 adult patients who underwent full median sternotomy for cardiac surgery were analyzed retrospectively at our institution. DSWI occurred in 455 (1.2%), of whom 364 (93.2%) were managed with pectoralis myocutaneous flap (PMF) and 33 (7.2%) with LHO. Univariate and multivariate analysis models were used to determine predictors of cumulative late mortality and adjusted survival curves were generated.

RESULTS

Among patients who received LHO, average age was 65.7 ± 9.7 years and a larger proportion of patients were male. A majority of patients (88%) had coronary bypass surgery, with bilateral internal mammary arteries use in only 21.2%. Mean length of stay (LOS) was 58.90 days and early hospital mortality occurred in 4 patients (12.1%). Patients who received LHO compared to only PMF had larger body mass index and had more heart failure. Furthermore, the hospital LOS was also significantly prolonged in the LHO group (58.9 vs. 27.4 days, p = .002), with a slightly higher in-hospital mortality (12.1% vs. 3.3%, p = .03). Late survival for LHO patients at 5 and 10 years was 71.9% and 44.8%, respectively.

CONCLUSION

Use of LHO is a safe and viable alternative to traditional myocutaneous flaps to manage complex DSWI. Early and late survival were favorable in this high-risk population.

An Outcomes Review of 330 Sternal Wound Reconstructions: Timing of Closure Does Make a Difference

BACKGROUND

Sternal wound infection and dehiscence following cardiac surgery remain difficult clinical problems with high morbidity. Older classification systems regarding timing to reconstruction do not take into account recent improvements in critical care, wound vacuum-assisted closure use, or next-generation antibiotic therapies, which may prolong time to reconstruction.

METHODS

Records of patients undergoing sternal wound reconstruction performed by the senior author (J.A.A.) from 1996 to 2018 at a high-volume cardiac surgery center were reviewed. Indications included sternal wound infection or dehiscence. All patients underwent single-stage removal of hardware, débridement, and flap closure. Patients were divided into two groups based on timing of wound closure after cardiac surgery: less than 30 days or greater than or equal to 30 days.

RESULTS

Of the 505 patients identified during the study period, 330 had sufficient data for analysis. Mean time to sternal wound surgery was 15.7 days in the early group compared to 64.4 days (p < 0.01) beyond 30 days. Postdébridement cultures were positive in 72 percent versus 62.5 percent of patients (p = 0.11), whereas rates of postoperative infection were significantly higher in the delayed group: 1.9 percent versus 9.5 percent (p < 0.01). Partial wound dehiscence rates were also higher after 30 days (1.9 percent versus 11.3 percent; p < 0.01), whereas total length of stay was decreased. Use of wound vacuum-assisted closure was significantly associated with reconstruction beyond 30 days (p < 0.01).

CONCLUSIONS

Although performing sternal wound reconstruction more than 30 days after initial cardiac surgery was associated with a shorter overall hospital length of stay and higher extubation rates in the operating room, these patients also had elevated postoperative infection and wound complication rates. The authors thus recommend not delaying definitive surgical reconstruction when possible.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Fluorescence in situ Hybridization (FISH) in the Microbiological Diagnostic of Deep Sternal Wound Infection (DSWI)

Purpose

Postoperative mediastinitis after cardiac surgery is still a devastating complication. Insufficient microbiological specimens obtained by superficial swabbing may only detect bacteria on the surface, but pathogens that are localized in the deep tissue may be missed. The aim of this study was to analyze deep sternal wound infection (DSWI) samples by conventional microbiological procedures and fluorescence in situ hybridization (FISH) in order to discuss a diagnostic benefit of the culture-independent methods and to map spatial organization of pathogens and microbial biofilms in the wounds.

Methods

Samples from 12 patients were collected and analyzed using classic microbiological culture and FISH in combination with molecular nucleic acid amplification techniques (FISHseq). Frequency of and the time to occurrence of a DSWI was recorded, previous operative interventions, complications, as well as individual risk factors and the microbiologic results were documented.

Results

Tissue samples were taken from 12 patients suffering from DSWI. Classical microbiological culture resulted in the growth of microorganisms in the specimens of five patients (42%), including bacteria and in one case Candida. FISHseq gave additional diagnostic information in five cases (41%) and confirmed culture results in seven cases (59%).

Conclusion

Microbial biofilms are not always present in DSWI wounds, but microorganisms are distributed in a “patchy” pattern in the tissue. Therefore, a deep excision of the wound has to be performed to control the infection. We recommend to analyze at least two wound samples from different locations by culture and in difficult to interpret cases, additional molecular biological analysis by FISHseq.

The management of deep sternal wound infection: Literature review and reconstructive algorithm

Deep sternal wound infection (DSWI) is an important complication of open thoracic surgery, with a reported incidence of 0.5-6%. Given its association with increased morbidity, mortality, inpatient duration, financial burden, and re-operation rates, an aggressive approach to treatment is mandated. Flap reconstruction has become the standard of care, with studies demonstrating improved outcomes with reduced mortality and resource usage in patients undergoing early versus delayed flap reconstruction. Despite this, no evidence-based standard for the management of DSWI exists. We performed a thorough review of the literature to identify principles in management, using a PRISMA compliant methodology. Ovid-Embase, Medline and PubMed databases were searched for relevant papers using the search terms "deep sternal wound infection," and "post-sternotomy mediastinitis" to December 2019. Duplicates were removed, and the search narrowed to look at specific areas of interest i.e. negative pressure wound therapy, flap reconstruction, and rigid fixation. The reference list of included articles underwent full text review. No randomized controlled trials were identified. We review the current management techniques for patients with DSWI, and raise awareness for the need for further high quality studies, and a standardized national cardiothoracic-plastic surgery guideline to guide management. Based on our findings and the authors' own experience in this area, we provide evidence-based recommendations. We also propose a reconstructive algorithm.

Superior epigastric artery perforator flap for reconstruction of deep sternal wound infection

BACKGROUND

The treatment of deep wound sternal infection requires loco-regional pedicled flaps, usually with muscular flaps. Perforator propeller flaps represent the ultimate progress in the history of reconstructive surgery. We report here our experience with the superior epigastric artery perforator (SEAP) flaps to repair sternal defect.

PATIENTS AND METHODS

Six patients presenting deep sternal wounds infection were treated with SEAP propeller flap, between March 2015 and June 2017. The mean age was 71.5 (range 53-83) years. The mean length and width of the defect were 16.2 × 7 cm (ranging 8-20 × 4-10). An elliptical skin flap pedicled on the SEAP was harvested in the inframammary fold and rotated up to 90° to cover the defect.

RESULTS

All SEAP flaps achieved a successful entire coverage of the defect. The mean size of the skin paddle of the flap was 20.2 × 7.3 cm (ranging 14-27 × 6-9). All flaps were able to provide a complete sternal wound cover. Venous congestion was present in five cases and adequately treated by leech therapy; necrosis was distal in one case, and interesting the entire superficial flap in two cases but with deep tissues remaining viable and able to cover the mediastinum: an infected flap required revision. Satisfyingly, at 2-years postoperative follow-up all-patients were alive with a successful mediastinal cover.

CONCLUSIONS

The SEAP Perforator propeller flap is an alternative to muscle flaps to achieve treatment of deep and large sternal wound infection.

Sternotomy Wound Closure: Equivalent Results with Less Surgery

Background:

Mediastinitis after a median sternotomy can be life-threatening. The advent of pedicle flap–based treatment has resulted in an improvement in both morbidity and mortality. However, significant morbidities can still occur following the use of flaps for sternal closure, particularly in patients with comorbidities. To minimize an extensive surgical dissection, we modified our approach to reconstruction using a modified subpectoral approach, leaving the overlying skin attached. This technique focuses primarily on controlling wound tension rather than on maximal muscle coverage. This study is a retrospective review of 58 consecutive patients treated with this approach, by a single surgeon.

Methods:

Fifty-eight consecutive patients treated between 2008 and 2019 were included. All patients received the same procedure regardless of the degree of illness, the extent of tissue loss, and the size of sternal defect. Treatment included thorough debridement, with total sternectomy (if required); limited dissection of the pectoralis major muscle off the chest wall to the level of the pectoralis minor without skin and subcutaneous undermining; no release of the insertion of the pectoralis or use of the rectus abdominis; and midline closure over drains connected to wall suction to obliterate dead space.

Results:

Reoperations were required in 7 patients (12%). Of these, only 4 (6.9%) were related to continued sternal osteomyelitis. The other reoperations were for hematoma evacuation, breast fat necrosis, and skin necrosis. There were no operative mortalities.

Conclusion:

Chest closure using minimal dissection and tension release is safe, efficient, and associated with a complication rate equivalent to more extensive procedures reported in the literature despite significant comorbidities.

Deep sternal wound infection following cardiac surgery: A comparison of the monolateral with the bilateral pectoralis major flaps

Deep sternal wound infections are a serious complication following sternotomy for cardiothoracic surgery. "Conventional" treatment provides debridement and secondary closure or closed catheter irrigation. The combination of the Negative Pressure Therapy with flap coverages is an accepted technique and one or both Pectoralis Major muscles could be chosen. A multistep protocol was adopted. One hundred and sixty seven patients were treated with the combination of Negative Pressure Therapy with the Pectoralis Major muscle flap: 86 monolateral flap and 81 bilateral flap reconstruction. The main complications (hematoma, seroma, dehiscence, and re-infection), the need for re-intervention, mortality rates, Intensive Care Unit, and hospitalisation time were assessed. The mono-pectoralis group had fewer complications and need for revision, with a shorter hospital stay. A statistically significant difference emerged for the hematoma rate (P = .0079). Monolateral flap should to be preferred because with the same coverage effectiveness, it guarantees the saving of controlateral muscle with its functionality and the possibility of its use in case of failure. Furthermore, as the technique is less invasive, it can be reserved for more fragile patients.

Vacuum-assisted closure therapy combined with bi-pectoral muscle flap for the treatment of deep sternal wound infections

Deep sternal wound infection (DSWI) is a fatal complication after median sternotomy. This study was to assess the effect of vacuum-assisted closure (VAC) combined with bi-pectoral muscle advancement flap therapy on rehabilitation for the treatment of DSWI. Fifty-two patients with DSWI underwent treatment of VAC and bi-pectoral muscle flap. These patients were followed-up 12 months postoperation. The patient characteristics, duration of VAC therapy, the mean hospital stay, and postoperative complications were retrospectively analysed. All patients underwent 1 to 3 VAC treatment sessions before closure. Fifty-one of 52 DSWI patients were cured to discharge; the mean hospital stay was 26.5 days. The drainage tube continued to drain a large amount of bloody fluid in three patients after the wound was closed. Respiratory failure occurred in one patient with severe mediastinal and pulmonary infections and died eventually in hospital. One patient died of acute cerebral haemorrhage during the12-month follow-up. VAC therapy combined with bi-pectoral muscle flap is a simple and effective treatment for DSWIs with short hospital stays and few complications. However, this is a retrospective case series presentation with no comparison group; further large-scale controlled studies are needed.

Reconstruction of a deep sternal wound with exposed pericardium using an IMAP propeller flap: A case report

The results of this case suggest that the IMAP propeller flap may be a viable and safe option for deep sternal wound reconstruction with minimal donor-site morbidity.

Deep sternal wound infection - latissimus dorsi flap is a reliable option for reconstruction of the thoracic wall

Background

At present, data describing patients’ long-term outcomes, quality of life, and survival after deep sternal wound infection are rarely available.

The purpose of our study was to evaluate functional outcome and patient well-being after debridement and reconstruction of the sternal defect using a pedicled latissimus dorsi flap following deep sternal wound infection (DSWI).

Methods

This retrospective analysis reviewed 106 cases of DSWI after open-heart surgery treated between May 1, 2012, and May 31, 2015. The parameters of interest were demographic and medical data, including comorbidity and mortality. Follow-up consisted of physical examination of the patients using a specific shoulder assessment, including strength tests and measurements of pulmonary function.

Results

The population consisted of 69 (65%) male and 37 (35%) female patients. Their average age at the time of plastic surgery was 69 years (range: 35–85). The 30-day mortality was 20% (n = 21); after one-year, mortality was 47% (n = 50), and at follow-up, it was 54% (n = 58).

Heart surgery was elective in 45 cases (42%), urgent in 31 cases (29%) and for emergency reasons in 30 cases (28%). The preoperative European System for Cardiac Operative Risk Evaluation (EuroSCORE) averaged 16.3 (range: 0.88–76.76).

On the dynamometer assessment, a value of 181 Newton (N) (±97) could be achieved on the donor side, in contrast to 205 N (±91) on the contralateral side.

The inspiratory vital capacity of the lung was reduced to an average of 70.58% (range: 26–118), and the forced expiratory volume in 1 s was decreased to an average of 69.85% (range: 38.2–118).

Conclusions

Given that only small adverse effects in shoulder function, strength, and pulmonary function were observed, the latissimus dorsi flap appears to be a safe and reliable option for the reconstruction of the sternal region after DSWI.

Pectoralis major turnover flap based on thoracoacromial vessels for sternal dehiscence

BACKGROUND

Reconstruction of long and deep sternal defects has been challenging. The pectoralis major can be used in the conventional turnover method that requires the internal thoracic vessel. We developed a new turnover pectoralis major flap based on thoracoacromial vessels. The purpose of this report is to present results from 14 patients.

METHODS

Fourteen patients with a mean age of 73.6 years (range, 53-83 years) who had sternal defects underwent reconstruction via this procedure. The defects were caused by mediastinitis and sternal osteomyelitis in six and eight patients, respectively. The internal thoracic artery (ITA) was harvested in two patients. The mean defect size was 2.4 × 15.5 cm (ranging 1-4.3 × 13-18 cm). After elevation of the lateral border of the muscle and ligation of the third to fifth perforators from ITA, the lateral side was turned over and the medial lower portion of the flap was additionally transplanted to the defect.

RESULTS

The mean flap size was 10.7 × 18 cm (ranging 9-13 × 15-21 cm). For 11 patients, defects healed without any complications. Discharge after flap reconstruction was observed in three patients, two of whom were managed using conservative treatments. Only one patient who needed additional debridement required transplantation of the contralateral pectoral major flap.

CONCLUSIONS

This muscle flap is nourished primarily by the thoracoacromial vessel. The long length and large volume of the muscle flap could be successfully turned over with this procedure even in patients that had their internal thoracic artery sacrificed.

Measurement of Adhesion of Sternal Wires to a Novel Bioactive Glass-Based Adhesive

Stainless steel wires are the standard method for sternal closure because of their strength and rigidity, the simplicity of the process, and the short healing time that results from their application. Despite this, problems still exist with sternal stability due to micromotion between the two halves of the dissected and wired sternum. Recently, a novel glass-based adhesive was developed which, in cadaveric trials and in conjunction with wiring, was shown to restrict this micromotion. However, in order to avoid complications during resternotomy, the adhesive should adhere only to the bone and not the sternal wire. In this study, sternal wires were embedded in 8 mm discs manufactured from the novel glass-based adhesive and the constructs were then incubated at 37 °C for one, seven, and 30 days. The discs were manufactured in two different thicknesses: 2 and 3 mm. Wire pull-out tests were then performed on the constructs at three different strain rates (1, 0.1, and 0.01 mm/min). No statistically significant difference in pull-out force was found regardless of incubation time, loading rate, or construct thickness. The pull-out forces recorded were consistent with static friction between the wire and adhesive, rather than the adhesion between them. Scanning electron micrographs provided further proof of this. These results indicate that the novel adhesive may be suitable for sternal fixation without complicating a potential resternotomy.

Cadaveric evaluation of sternal reconstruction using the pectoralis muscle flap

BACKGROUND

Deep sternal wound infection is a significant complication of open cardiac surgery associated with increased mortality and morbidity. The use of muscle flaps, such as the pectoralis major advancement flap, in deep sternal wound infection reconstruction reduces hospital stay and mortality. However, the lower end of the sternum is remote from the vascular supply and cover is therefore problematic in many cases.

METHODS

This study aimed to determine the distance (cm) and surface area (cm² ) of sternum covered when the pectoralis major muscle is sequentially dissected from the sternocostal origin and humeral insertion using 10 cadaveric specimens.

RESULTS

The largest proportion of sternum was covered when both the origin and insertion were divided, allowing the flap to be islanded on its vascular pedicle. There was a statistically significant difference when the pectoralis major was divided from the origin and insertion compared to division of the origin alone (P < 0.01). The average area covered with sternocostal origin division alone was 55.43 cm² compared to 85.36 cm² after division of both the origin and insertion.

CONCLUSION

Division of both the sternocostal origin and humeral insertion of the pectoralis major muscle represents an effective means to increase sternal coverage. This study describes the average distance and area covered by sliding pectoralis major muscle advancement flaps. These measurements could better inform plastic surgeons when evaluating reconstructive options in sternal defects.

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.

Unilateral pectoralis major muscle flap for the treatment of sternal wounds due to Ludwig's angina

Necrotising descending mediastinitis may rarely originate from Ludwig's angina, which is an infection of the submandibular space. The use of the bilateral pectoralis major muscle flap for the treatment of sternal wound dehiscence is common, but reports of the unilateral application of this flap are scarce. This study aims to report the use of the unilateral pectoralis major muscle flap for the treatment of sternotomy dehiscence in a patient with mediastinitis due to Ludwig's angina. A 21-year-old male patient underwent an exploratory cervicotomy and median sternotomy for drainage of a submandibular infection that extended to the anterior, retropharyngeal and mediastinal cervical spaces. The patient had dehiscence of the sternal wound, and the unilateral pectoralis major muscle flap was used for reconstruction of the defect. This flap was able to completely cover the area of dehiscence of the sternotomy, and the patient presented a good postoperative evolution, without complications. The reconstruction technique using the unilateral pectoralis major muscle flap was considered a good option for the treatment of sternotomy dehiscence. It is an adjuvant method in the treatment of infections such as mediastinitis and osteomyelitis of the sternum secondary to Ludwig's angina, allowing a stable coverage of the sternum.

Preliminary result with incisional negative pressure wound therapy and pectoralis major muscle flap for median sternotomy wound infection in a high-risk patient population

Deep sternal wound infection (DSWI) represents a dangerous complication that can follow open-heart surgery with median sternotomy access. Muscle flaps, such as monolateral pectoralis major muscle flap (MPMF), represent the main choices for sternal wound coverage and infection control. Negative pressure incision management system has proven to be able to reduce the incidence of these wounds' complications. Prevena™ represents one of these incision management systems and we aimed to evaluate its benefits. A total of 78 patients with major risk factors that presented post-sternotomy DSWI following cardiac surgery was selected. Thrity patients were treated with MPMF and Prevena™ (study group). Control group consisted of 48 patients treated with MPMF and conventional wound dressings. During the follow-up period, 4 (13%) adverse events occurred in the study group, whereas 18 complications occurred (37·5%) in the control group. Surgical revision necessity and mean postoperative time spent in the intensive care unit were both higher in the control group. Our results evidenced Prevena™ system's ability in improving the outcome of DSWI surgical treatment with MPMF in a high-risk patient population.

A National Study of the Impact of Delayed Flap Timing for Treatment of Patients with Deep Sternal Wound Infection

BACKGROUND

This study aimed to evaluate the impact of delayed flap closure on mortality and resource use for treatment of deep sternal wound infection.

METHODS

The authors analyzed the Truven MarketScan Databases from 2009 to 2013 to identify adult patients who developed deep sternal wound infection after open cardiac surgery and who underwent flap closure for treatment. A multivariable logistic regression model was created to evaluate the relationship between mortality and flap timing. Multivariable Poisson regressions were used to investigate the relationship between flap timing and number of procedures, number of hospitalizations, and length of stay outcomes. A multivariable log-linear regression model was created for cost analysis. All analyses were adjusted for patient risk factors and treatment characteristics.

RESULTS

The authors identified 612 patients with deep sternal wound infection who underwent flap closure. The timing of flap closure was delayed more than 7 days after diagnosis in 39 percent of patients. Delayed time to flap closure greater than 3 days after diagnosis of infection was associated with higher mortality odds for delay 4 to 7 days (OR, 2.94) and delay greater than 7 days (OR, 2.75; p < 0.03), greater additional procedures for delay 4 to 7 days (incidence rate ratio, 1.72) and delay greater than 7 days (incidence rate ratio, 1.93; p < 0.001), and up to 43 percent longer hospital length of stay and 37 percent greater costs compared with patients undergoing flap closure 0 to 3 days after diagnosis.

CONCLUSIONS

Delay in flap closure was associated with greater mortality and resource use. Prompt involvement of reconstructive surgeons may improve quality and efficiency of deep sternal wound infection care.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Omentum flap as a salvage procedure in deep sternal wound infection

INTRODUCTION

Deep sternal wound infections (DSWIs) are rare but devastating complication after median sternotomy following cardiac surgery. Especially in the presence of artificial material or inadequate preliminary muscle flaps, the pedicled omentum flap is due to its immunological properties, the predetermined flap in salvage procedures.

METHODS

We treated 14 patients suffering a mediastinitis and open thorax using a pedicled omentoplasty as a salvage procedure because of persisting DSWIs. Omentoplasty was performed in combination with a split skin graft and the wound was closed by a vacuum-assisted therapy for 7 days. The patients' sex and comorbid risk factors supporting DSWIs as well as the postoperative complications were recorded.

RESULTS

Retrospective analysis of 14 patients (10 males and four females) after a follow-up time of 24 months was performed. The average age was 75 years (range: 67-83). Heart surgery took place electively in eight cases, in three cases urgently and three for emergency reasons. The preoperative Euro Score was 16 (range 3.51-42.58). We had no flap loss in any patients. The skin graft showed a full take in all patients. Two patients needed revision of an abdominal wound dehiscence after laparotomy and one patient developed hernia in the late outcome.

DISCUSSION

The greater omentum flap has, over many years, become an ideal partner in the coverage and treatment of DSWIs. Especially due to its immunologic capacity and amorphous structure, it has the ability to fill up cavities and cover infected artificial material so residual infections can be controlled.

European Association for Cardio-Thoracic Surgery expert consensus statement on the prevention and management of mediastinitis

Mediastinitis continues to be an important and life-threatening complication after median sternotomy despite advances in prevention and treatment strategies, with an incidence of 0.25-5%. It can also occur as extension of infection from adjacent structures such as the oesophagus, airways and lungs, or as descending necrotizing infection from the head and neck. In addition, there is a chronic form of 'chronic fibrosing mediastinitis' usually caused by granulomatous infections. In this expert consensus, the evidence for strategies for treatment and prevention of mediatinitis is reviewed in detail aiming at reducing the incidence and optimizing the management of this serious condition.

Therapy options in deep sternal wound infection: Sternal plating versus muscle flap

Background

Management of deep sternal wound infection (DSWI) in cardiac surgical patients still remains challenging. A variety of treatment strategies has been described. Aim of this cohort study was to analyse two different treatment strategies for DSWI: titanium sternal plating system (TSFS) and muscle flap coverage (MFC).

Methods

Between January 2007 and December 2011, from 3122 patients undergoing cardiac surgery 42 were identified with DSWI and treated with one of the above mentioned strategies. In-hospital data were collected, follow-up performed by telephone and assessment of Quality of Life (QoL) using the SF-12 Health Survey Questionnaire.

Results

20 patients with deep sternal wound infection were stabilized with TSFS and 22 patients treated with MFC. Preoperative demographics and risk factors did not reveal any significant differences. Patients treated with TSFS had a significantly shorter operation time (p<0.05) and shorter hospitalization (p<0.05). A tendency towards lower mortality rate (p = n.s.) and less re-interventions were also noted (plating 0.6 vs. flap 1.17 per patient, n.s.). Quality of Life in the TSFS group for the physical-summary-score was significantly elevated compared to the MFC group (p<0.05). Relating to chest stability and cosmetic result the treatment with TSFS showed superior results, but the usage of MFC gave the patients more freedom in breathing and less chest pain.

Conclusion

Our results demonstrate that the use of TSFS is a feasible and safe alternative in DSWI. However, MFC remains an absolutely essential option for complicated DSWI since the amount of perfused tissue can be the key for infection control.

The Split Pectoralis Flap: Combining the Benefits of Pectoralis Major Advancement and Turnover Techniques in One Flap

BACKGROUND

The pectoralis major is a versatile flap used as an advancement or turnover flap for sternal wound treatment. The advancement flap provides suboptimal inferior sternal coverage and poorly fills mediastinal dead space. The turnover flap covers the inferior sternum and fills dead space but requires disinsertion of the muscle from the humerus, resulting in functional loss and cosmetic deformity.

METHODS

The authors describe a new technique of splitting the pectoralis muscle along its fibers, using the superior portion as an advancement flap and the inferior portion as a turnover flap.

RESULTS

Eleven patients underwent the described technique. Nine patients healed without complications or repeated operations. One patient had a recurrent aortic graft infection requiring reoperation. One patient had a postoperative seroma requiring incision and drainage.

CONCLUSION

Using the pectoralis as an advancement and turnover flap allows inferior sternum and mediastinum coverage using one donor site and maintaining the function of the muscle and preventing cosmetic deformity.

Limited Bilateral Advancement of the Sternocostal Head of Pectoralis Major for Sternal Reconstruction: Preserving the Axillary Fold

The introduction of well-vascularized flaps for infected sternotomy wound reconstruction has improved mortality rates dramatically. Multiple variations of the pectoralis major flap have been described in this context. However, unresolved limitations of this flap include poor cosmesis and problematic coverage of the inferior third of the sternotomy wound. We describe an approach to address these issues. The humeral attachments are preserved and bilateral muscles are advanced in a limited fashion. The left sternocostal head is advanced medially and rotated anticlockwise, using this portion to fill the upper half of the sternum while the caudal portion of the right pectoralis muscle is used as a turnover flap at the lower half of the wound. In all 25 patients, the anterior axillary fold was preserved bilaterally and the infection completely resolved. Complications included 3 cases of hematoma, 2 cases of coagulopathy, and 1 late bone sequestrum (aseptic). Although the study had a limited sample size, we had a high rate of success and few complications. With the preservation of bilateral axillary folds, good cosmesis, and adequate wound coverage, we recommend this modification of the pectoralis major flap in even complicated cases of mediastinitis.

Retained Foreign Bodies, The Cause of Postmidsternotomy Sinuses: Case Reports

Postmidsternotomy chronic si nuses have received little attention in the literature. They are usually not a life-threatening complication but may sometimes lead to grave condi tions such as acute mediastinitis, in fection of prosthetic valves or vascu lar grafts, and sternal osteomyelitis.

Most patients suffering from this problem usually undergo several un successful surgical interventions ow ing to failure to recognize the under lying cause in the first place. The cause of the sinus is nearly always a foreign body situated deep within the tissues from the time of the original operation. The authors believe that it is of utmost importance that the ex tent of the sinus be demonstrated prior to surgery by sinogram or other imaging techniques. Unless the for eign object is identified and removed, the sinus will recur.

Over the last four years, they treated 70 patients with postmid sternotomy complications; 14 of them had sternal sinuses. In each of the 14, some grade of wound infection oc curred at the immediate postopera tive period following the original op eration. In all cases, a foreign body was identified prior to or during ex ploration and removed. These in cluded wires, pacemaker electrodes, silk sutures, a Teflon pledget, and a piece of steridrape. Follow-up, rang ing up to twenty-seven months, shows no recurrence of the sinuses.

Latitude of the study place and age of the patient are associated with incidence of mediastinitis and microbiology in open-heart surgery: a systematic review and meta-analysis

OBJECTIVE

We aimed to summarize the pooled frequency of mediastinitis following open-heart surgery caused by Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), and Gram-negative bacteria.

DESIGN

This study was a systematic review and a meta-analysis of prospective and retrospective cohort studies.

MATERIALS AND METHODS

We searched the literature, and a total of 97 cohort studies were identified. Random-effect model was used to synthesize the results. Heterogeneity between studies was examined by subgroup and meta-regression analyses, considering study and patient-level variables. Small-study effect was evaluated.

RESULTS

Substantial heterogeneity was present. The estimated incidence of mediastinitis evaluated from 97 studies was 1.58% (95% confidence intervals [CI] 1.42, 1.75) and that of Gram-positive bacteria, Gram-negative bacteria, and MRSA bacteria evaluated from 63 studies was 0.90% (95% CI 0.81, 1.21), 0.24% (95% CI 0.18, 0.32), and 0.08% (95% CI 0.05, 0.12), respectively. A meta-regression pinpointed negative association between the frequency of mediastinitis and latitude of study place and positive association between the frequency of mediastinitis and the age of the patient at operation. Multivariate meta-regression showed that prospective cohort design and age of the patients and latitude of study place together or in combination accounted for 17% of heterogeneity for end point frequency of mediastinitis, 16.3% for Gram-positive bacteria, 14.7% for Gram-negative bacteria, and 23.3% for MRSA bacteria.

CONCLUSION

Evidence from this study suggests the importance of latitude of study place and advanced age as risk factors of mediastinitis. Latitude is a marker of thermally regulated bacterial virulence and other local surgical practice. There is concern of increasing risk of mediastinitis and of MRSA in elderly patients undergoing sternotomy.

Results of the modified bi-pectoral muscle flap procedure for post-sternotomy deep wound infection

PURPOSE

Post-sternotomy deep sternal wound infection (DSWI) is a severe complication of cardiac surgery. The introduction of omental and muscle flaps has resulted in a significant decrease in morbidity and mortality. In this article, we present the findings for a series of 55 consecutive patients with DSWI treated using an alternative bi-pectoral musculofascial flap technique.

METHODS

The patients were stratified into two groups (one-or two-stage intervention). Patients with septic wounds initially underwent debridement and wound treatment, while vacuum therapy was used in a subset of the subjects. All patients were treated with wound debridement and bi-pectoral advancement flap reconstruction.

RESULTS

30-day mortality was 5.4%. Most patients (72%) were treated in two stages, while vacuum therapy was used in 20% of the patients. The mean number of hospitalization days was 8 and 12 for the one- and the two-stage groups, respectively. Reconstruction was successful in all but three patients, each of whom developed recurrent infection. No major morbidity was reported at a mean follow-up of 82 months with excellent functional and aesthetic outcomes.

CONCLUSIONS

Pectoralis-major muscle flaps remain relevant in the modern management of post-sternotomy mediastinitis. The addition of an omental flap should be considered in cases in which the lower sternum is involved. Prompt diagnosis and a meticulous surgical technique ensure favorable results for the majority of patients.