Mediastinitis After Congenital Heart Surgery: Epidemiology, Clinical Features and Outcomes.

Mediastinitis after surgery for congenital heart disease has a great impact on morbidity and mortality. However, there are scarce studies focused on the epidemiology of postsurgical mediastinitis in pediatric patients. In this 18-year period retrospective study, the cumulative incidence of mediastinitis was low: 0.64%, (95% confidence interval: 0.36-1.1). Gram-negative bacilli were common (35%). The mortality rate was 7.1%, associated with fungal infection.

Post-cardiac surgery fungal mediastinitis: clinical features, pathogens and outcome.

OBJECTIVES: The occurrence of mediastinitis after cardiac surgery remains a rare and severe complication associated with poor outcomes. Whereas bacterial mediastinitis have been largely described, little is known about their fungal etiologies. We report incidence, characteristics and outcome of post-cardiac surgery fungal mediastinitis. METHODS: Multicenter retrospective study among 10 intensive care units (ICU) in France and Belgium of proven cases of fungal mediastinitis after cardiac surgery (2009-2019). RESULTS: Among 73,688 cardiac surgery procedures, 40 patients developed fungal mediastinitis. Five were supported with left ventricular assist device and five with veno-arterial extracorporeal membrane oxygenation before initial surgery. Twelve patients received prior heart transplantation. Interval between initial surgery and mediastinitis was 38 [17-61] days. Only half of the patients showed local signs of infection. Septic shock was uncommon at diagnosis (12.5%). Forty-three fungal strains were identified: Candida spp. (34 patients), Trichosporon spp. (5 patients) and Aspergillus spp. (4 patients). Hospital mortality was 58%. Survivors were younger (59 [43-65] vs. 65 [61-73] yo; p = 0.013), had lower body mass index (24 [20-26] vs. 30 [24-32] kg/m2; p = 0.028) and lower Simplified Acute Physiology Score II score at ICU admission (37 [28-40] vs. 54 [34-61]; p = 0.012). CONCLUSION: Fungal mediastinitis is a very rare complication after cardiac surgery, associated with a high mortality rate. This entity should be suspected in patients with a smoldering infectious postoperative course, especially those supported with short- or long-term invasive cardiac support devices, or following heart transplantation.

Kazachstania slooffiae: An unexpected journey to a human pleural sample.

We report a case of a 50-year-old shepherd hospitalized in intensive care unit for hiatal hernia complicated by an occlusive syndrome. In post-surgery, an acute respiratory distress occurs due to mediastinitis with large pleural effusion. At the laboratory, direct examination of the pleural sample revealed the presence of pseudohyphae. Kazachstania slooffiae was identified by Mass Spectrometry and confirmed by DNA sequencing. This uncommon yeast has never been previously described in human infections. Although its pathogenicity is not well known, K. slooffiae should be considered in the case of critically ill patients.

Prevention of Sternal Wound Infections in Women Using an External Sternum Fixation Corset.

PURPOSE: Deep sternal wound infection (DSWI) and mediastinitis are devastating complications after median sternotomy. Previous studies demonstrated an effective prevention of sternal wound infection (SWI) using an external sternal corset in high-risk cardiac surgery patients. The aim of this study is to assess the preventive effect of the Stern-E-Fix corset in high-risk poststernotomy female patients. METHODS: A total of 145 high-risk female patients undergoing cardiac surgery through median sternotomy were retrospectively analyzed. Patients were divided into group A (n = 71), who received the Stern-E-Fix corset (Fendel & Keuchen GmbH, Aachen, Germany), and group B (n = 74), who received the elastic thorax bandage (SanThorax) postoperatively for 6 weeks. The mean follow-up period was 12 weeks. RESULTS: Incidence of SWI was 7% in group A vs. 17.6% in group B (p = 0.025). One patient presented with DSWI in group A vs. seven patients in group B (p = 0.063). No patient developed mediastinitis in group A vs. four patients in group B (p = 0.121). In all, 4.2% of group A patients required operative wound therapy vs. 16.2% of group B patients (p = 0.026). The length of hospital stay was significantly longer in group B (p = 0.006). CONCLUSION: Using an external supportive sternal corset (Stern-E-Fix) yields a significantly better and effective prevention against development of sternal dehiscence, DSWI, and mediastinitis in high-risk poststernotomy female patients.

Descending Necrotizing Mediastinitis: Analysis of 9 Cases in Our Hospital.

OBJECTIVES: Descending necrotizing mediastinitis (DNM) is a serious and progressive infection involving the neck and chest and with high mortality if not treated quickly and properly. The aim of this study is to share our practices for managing this condition. METHODS: We retrospectively evaluated 9 patients diagnosed with DNM in our hospital between January 2006 and October 2019. Age, gender, origin of infection, length of hospital stay, microorganisms present, type of surgical treatment, and clinical outcomes were reviewed. RESULTS: All patients underwent surgery to drain neck and mediastinal secretions and collections. Three (33.3%) patients were treated with transcervical drainage alone, and 6 (66.7%) patients were treated with combined transcervical and transthoracic drainage. Reoperations were reported in 3 (33.3%) cases. The average length of hospital stay was 22.78 ± 10.05 days (range: 9-40 days). The average length of intensive care unit stay was 6.44 ± 10.10 days (range: 0-25 days). There were no in-hospital deaths, and all patients were discharged home with good outcomes. CONCLUSIONS: To improve the prognosis of DNM, we suggest early and adequate debridement of all affected areas along with the proper use of antibiotics. A multidisciplinary approach involving both cardiothoracic and ENT surgeons is also required.

Emerging trends in mediastinitis: National Veterans Health Administration experience with methicillin-resistant Staphylococcus aureus prevention.

OBJECTIVES: Perioperative bacterial decolonization and prophylactic antibiotic therapy at the Veterans Affairs Health Care System have changed over the past decade. Our objectives were to identify associated changes in the microbiology of mediastinitis and to perform a contemporary survival analysis in patients with mediastinitis after isolated coronary artery bypass grafting procedure. METHODS: From January 2006 to December 2015, 45,323 consecutive patients underwent coronary artery bypass grafting at 83 medical centers. The Veterans Affairs Health Care System nationwide administrative database was queried to identify patients with postoperative mediastinitis and obtain patient-level data. Simple descriptive statistics and multivariable logistic regression were used to analyze microbiologic data and identify risk factors for infection. Poisson regression was used to determine yearly incidence estimates. Cox proportional hazard model identified predictors of long-term survival from date of operation. RESULTS: During the study period, 348 patients (0.78%) developed postoperative mediastinitis-with a stable rate of incidence (Cochrane-Armitage test, P = .69). Of patients with microbiologic data, 75.5% of infections (n = 188) were caused by gram-positive and 24.5% (n = 61) gram-negative organisms. The incidence of methicillin-resistant Staphylococcus aureus mediastinitis decreased during the study period (Cochrane-Armitage test, P = .013). Gram-negative mediastinitis occurred earlier than gram-positive mediastinitis (median, 15.0 vs 25.0 days; P < .0001). Patients with mediastinitis did not have increased 30-day mortality (2.0% vs 1.9%; P = .9), but had worse long-term survival compared with uninfected patients (P < .0001). CONCLUSIONS: The incidence of methicillin-resistant S aureus mediastinitis has decreased over the past decade. Gram-negative bacteria are responsible for 1 in 4 cases of mediastinitis and infection is diagnosed earlier in the postoperative period than gram-positive mediastinitis. These findings highlight the need for efforts to prevent gram-negative and methicillin-susceptible S aureus mediastinitis.

Staphylococcus aureus Descending Necrotizing Mediastinitis in a Healthy Adult.

Descending necrotizing mediastinitis (DNM) is a severe form of mediastinitis with high mortality rates due to the rapid progression of infection into the mediastinum through tissue planes, often from a dental or pharyngeal source. We present a case of monomicrobial methicillin-resistant Staphylococcus aureus DNM in a healthy young man who was initially misdiagnosed with strep throat. This is well described in the pediatric literature; however, DNM in adults is typically polymicrobial and occurs in those with comorbidities such as diabetes mellitus and older age. Survival is excellent with early identification of mediastinitis, prompt surgical intervention, and appropriate antibiotics.

Deep Neck Infection Complicated by Phlegmonous Esophagitis and Mediastinitis.

Descending necrotizing mediastinitis is a life-threatening disease that extends into the pretracheal, perivascular, retrovisceral, and/or prevertebral spaces, generally sparing the esophagus. We report a case of deep neck abscess complicated by phlegmonous esophagitis and mediastinitis. The patient was successfully treated with antibiotics and surgery, combining transcervical and bilateral thoracoscopic transthoracic mediastinal drainage. However, a pseudo-lumen with a large amount of pus remained in the esophagus. The septum between the true and the pseudo-lumen was cut endoscopically, after which the patient recovered well without any complications.

Aspergillus mediastinitis in a post-operative immunocompetent child.

Post-operative Aspergillus mediastinitis is regarded to be a devastating infection, usually affecting patients undergoing cardiothoracic surgery with specific predisposing factors characterised by a high mortality and chronic morbidity. Patient outcome after such a complication is extremely poor despite antifungal therapy and surgery. We describe the case of an immunocompetent 2-month-old child with obstructed supracardiac total anomalous pulmonary venous circulation (TAPVC) and severe pulmonary artery hypertension, who underwent TAPVC repair through median sternotomy and developed post-operative mediastinitis due to Aspergillus flavus.

[Infectious and inflammatory complications occurring after cardiac surgery in cardiac rehabilitation centres]. / Complications infectieuses et inflammatoires après chirurgie cardiaque survenues dans les services de réadaptations cardiaques.

Patients undergoing cardiac surgery are older, have complex pathologies and several comorbidities, but need to leave the hospital quickly! Therefore, the mission of cardiac rehabilitation centres has substantially changed. Indeed, if 15 to 25% of patients undergoing cardiac surgery will have a postoperative complication requiring a hospital management (infectious, pericardial, rhythmic, neurologic, pulmonary, digestive, etc.), more than 2/3 of these acute events could be managed by cardiac rehabilitation centres for a lower cost. Therefore, the quickest the patient is transferred to a cardiac rehabilitation centre, the easier the cardiac surgery centre could manage his beds. Infectious complications are the most dreadful, particularly mediastinitis.

Mediastinal tissue friability-An unreported complication from Mycobacterium chimaera infection post-cardiac surgery.

Mycobacterium chimaera can cause disseminated infection following cardiac surgery with cardiopulmonary bypass and contaminated heater-cooler devices. We discuss a 41-year-old man with a disseminated M. chimaera infection following surgery for a type A aortic dissection. His presentation included cachexia and dorsalgia with a work-up revealing vertebral osteomyelitis with an epidural abscess, bone marrow, and pulmonary infiltration, and fluid collection around his aortic graft. He received 1 month of antibiotics before the explantation of infected foreign material, mediastinal debridement, and aortic reconstruction. Complications included septic shock, respiratory and renal failure, mediastinitis, and four distal aortic anastomotic dehiscences from friable tissue and persistent infection.

Acute mediastinitis associated with tracheobronchial tuberculosis and aspergillosis: a case report and literature review.

Acute mediastinitis (AM) is a rare but life-threatening disease. Here, we report a case of AM secondary to endobronchial tuberculosis (EBTB) and pseudomembranous Aspergillus tracheobronchitis (PMATB) co-infection. EBTB was confirmed by tissue culture for Mycobacterium tuberculosis and GeneXpert MTB/RIF (Cepheid, Sunnyvale, CA, USA) detection (simultaneous detection of M. tuberculosis and resistance to rifampin) using endobronchial biopsies; PMATB was confirmed by histopathology. Even with antibiotic treatment and systemic support treatment, the patient died of massive hemoptysis on day 10 after admission. When immunocompromised hosts have AM, especially with central airway involvement, EBTB and aspergillosis should be considered potential causes. Bronchoscopy is helpful for rapid diagnosis and administering precise treatment.

[Clinical analysis of 61 cases of deep neck infection].

Objective: To explore the clinical experience in care for deep neck infection (DNI) and to analyze the factors influencing surgical treatment outcome. Methods: A retrospective analysis was conducted on 61 patients with DNI admitted to the Department of Otorhinolaryngology Head and Neck Surgery of Yantai Yuhuangding Hospital from March 2013 to April 2019, including 33 males and 28 females, aged from 6 months to 81 years with a median age of 49 years. Patients were divided into two groups, 31 cases with localized infection (neck abscess) in Group A and 30 cases with diffuse infection (neck necrotizing fasciitis) in Group B. Patients in two groups were compared for sex, age, hospital stay, diabetes, tracheostomy, drainage methods, mediastinal infection, and pathogenic bacteria. The influence of different drainage methods on hospital stay in Group A was analyzed. SPSS 25.0 software was used for statistical analysis. Results: Of the 61 patients, 45 patients underwent surgical incision and drainage (21 cases in Group A and 24 cases in Group B), 23 patients underwent ultrasound-guided fine needle aspiration (UG-FNA) and catheter drainage (10 cases in Group A and 13 cases in Group B), and 7 patients in Group B were treated with both drainage methods. Pathogens were cultured in 31 cases (50.82%). There were significant differences in hospital stay, drainage method and mediastinal infection (χ(2) values were 26.890, 8.687 and 6.035, respectively, P<0.05), but no significant difference was found in sex, age, diabetes, tracheotomy and pathogenic bacteria (χ(2) values were 0.157, 3.685, 2.434, 3.631 and 0.807, respectively, P>0.05) between the two groups. There was no significant difference in hospital stay between two drainage methods in patients in Group A (χ(2)=1.560, P>0.05). Conclusions: There were significant differences in hospital stay, drainage method and mediastinal infection between patients with localized infection and diffuse infection, as diffuse infection is often associated with serious complications. UG-FNA and catheter drainage is an optional method for the treatment of localized infection, with minimal invasion and no influence on hospital stay.

Descending necrotizing mediastinitis caused by Streptococcus constellatus in an immunocompetent patient: case report and review of the literature.

Descending necrotizing mediastinitis is a severe infection of the mediastinum. This syndrome manifests as fever and chest pain following cough and sputum production. A 49-year-old woman presented with fever and a 14-day history of pneumonia. CT showed mediastinal abscesses with a giant calcified mediastinal lymph node (21 × 18 mm) and pneumonia. Bronchoscopy by EBUS-TBNA under general anesthesia was performed. The pathogen found in the puncture culture was Streptococcus constellatus, and antibiotics (mezlocillin/sulbactam 3.375 IVGTT q8h) was administered. A proximal right main bronchial neoplasm, suspected lung cancer, was found and conformed to inflammatory granuloma. A total of 22 months post-discharge the patient was clinically stable. We also conducted a review of the literature for all Streptococcus constellatus descending necrotizing mediastinitis infections between 2011 and 2017.

Clinical study of an outbreak of postoperative mediastinitis caused by Serratia marcescens in adult cardiac surgery.

OBJECTIVES: Nosocomial infection caused by Serratia marcescens after cardiac surgery is rare but causes high rates of morbidity and mortality. Knowledge about postoperative mediastinitis due to S. marcescens is limited. The purpose of this work was to study the clinical presentation, management and outcome of an outbreak of postoperative sternal infection due to S. marcescens. METHODS: During a 7-week period, a total of 54 patients underwent open heart procedures in our hospital. A postoperative wound infection caused by S. marcescens was diagnosed in 10 patients. We performed a clinical study to investigate patient characteristics and outcomes as well as the possible source of the infection. RESULTS: The mean age of the infected patients was 74.5 ± 10 years. Mediastinitis was present in 6 cases, superficial wound infection in 3 and isolated bacteraemia in 1. Purulent exudate through the sternal incision was observed in all infected cases except in 1 patient, who presented only with bacteraemia. Serratia marcescens was isolated from the samples taken from all infected wounds. The mean time elapsed between the operation and the isolation S. marcescens was 5.9 ± 2.4 days. Response to treatment was favourable in all cases except 1, who died. Contamination of the aqueous chlorhexidine solution used to prepare the patients' skin with S. marcescens was reported. Microbiological studies demonstrated that S. marcescens strains isolated from patients and from the aqueous chlorhexidine solution belonged to the same clone. CONCLUSIONS: The use of an aqueous chlorhexidine solution contaminated with S. marcescens caused an outbreak of postoperative sternal wound infections. The time elapsed between wound contamination and signs of infection was brief, but the systemic inflammatory response and tissue necrosis were limited. Alcohol-based solutions are recommended for the prevention of surgical site infections.

Contained rupture of right ventricular outflow tract after Rastelli-type operation.

This report describes a 3-year-old infant with post-operative mediastinitis complicated by a contained rupture of the right ventricle. A contained rupture is recognised as the huge pulsating prominence of the anterior chest wall. CT confirmed blood communication between the right ventricular outflow tract and the cavity surrounded by the pectoral major musculocutaneous flap. This is a significant case in which severe adhesion between the right ventricle and the musculocutaneous flap could maintain her stable haemodynamics with a pulsating prominence.

A Technique for 360-Degree Rigid Sternal Fixation with Sternal Plates and Wire Cerclage.

Sternal instability after cardiac surgery can lead to poor bony healing, as well as deep sternal wound infections and mediastinitis. Rigid plate fixation is associated with greater stability and fewer complications compared with wire cerclage, however, rigid plate fixation alone lacks posterior stability of the sternum and may be less effective in morbidly obese or osteoporotic patients. This article describes a surgical technique of combined rigid plate fixation and wire cerclage that provides 360-degree stabilization for sternotomies in high-risk patients. We employed this technique in 40 patients with no incidence of deep sternal wound infection.

Mediastinitis in the intensive care unit patient: a narrative review.

BACKGROUND: Mediastinitis is a rare but severe infection, defined as an inflammation of the connective tissues and structures within the mediastinum. Due to its proximity to vital structures, mediastinitis represents a highly morbid pathological process associated with a high risk of mortality. In most cases mediastinitis requires treatment in the intensive care unit. OBJECTIVES: To highlight to the reader the clinical features of mediastinitis, to attempt to define each clinical scenario, to describe the responsible pathogens and finally to depict both the medical and surgical treatments. SOURCES: We performed a literature search of the PubMed and Cochrane libraries, limited for articles published between January 2003 and December 2018, reporting on acute mediastinitis. CONTENT: The term covers different entities of different aetiologies including deep sternal wound infection related to sternotomy; oesophageal perforation or anastomosis leakage; and finally descending necrotizing mediastinitis, often secondary to oropharyngeal abscess. The responsible pathogens and therefore subsequent management depends on the underlying aetiology. Empirical antimicrobial therapy should cover the suspected microorganisms while surgery and supportive measures should aim to reduce the inoculum of pathogens by providing adequate drainage and debridement. IMPLICATIONS: Literature concerning mediastinitis in the intensive care unit is relatively scarce. We have collated the evidence and reviewed the different causes and treatment options of acute mediastinitis with a particular focus on microbiological epidemiology. Future research in larger cohorts is needed to better understand the treatment of this difficult disease.

Derivation and validation of an early diagnostic score for mediastinitis after cardiothoracic surgery.

OBJECTIVES: The aim of this study was to elaborate on and validate a score for the early diagnosis of mediastinitis after cardiothoracic surgery. METHODS: Between 2007 and 2017, patients who experienced thoracic surgical-site infection after cardiothoracic surgery were enrolled. Laboratory, clinical, and chest CT findings were retrospectively analyzed. Patients were followed up until hospital discharge or intra-hospital death. Univariate and multivariate regression analyses were performed. RESULTS: 950 surgical-site infections were found and analyzed (131 mediastinitis, 819 superficial/deep infections). Of the 131 mediastinitis episodes, 88% required surgical thoracic debridement,Staphylococcus aureus was identified in 43%, and overall mortality was 42%. The following variables were related to mediastinitis diagnosis: sternal diastasis (OR=2.5; 95% confidence interval [95%CI]: 1.2-5.3; P=0.012), bilateral pleural effusion (OR=1.9; 95%CI: 1.0-3.6; P=0.04), leukocyte count ≥14,000cells/mm3 (OR=2.5; 95%CI: 1.3-4.7; P=0.006), male sex (OR=2; 95%CI: 1.11-4; P=0.022), and positive blood culture (OR=3.0; 95%CI: 1.6-5.6; P=0.001). The score predicted with reasonable accuracy mediastinitis in the derivation cohort (AUC-ROC, 0.7476) and the validation cohort (AUC-ROC, 0.7149). Groups with high (31%) and low (5%) risk of mediastinitis were identified. CONCLUSIONS: An early diagnostic score in patients with surgical-site infection after cardiothoracic surgery identified groups with a low and high risk for mediastinitis.

Clinical and Microbiological Analysis of Deep Sternal Wound Infections in Fifty-Two Consecutive Patients.

Background: Mediastinitis after cardiac surgery can lead to devastating consequences such as deep sternal wound infections (DSWI). Staphylococcus epidermidis and other coagulase-negative staphylococci belong to the physiological skin flora and therefore generally are not considered pathogenic agents. Thus, local resistance patterns of these bacterial species often recovered from wound specimens generally are ignored while choosing antibiotics for peri-operative prophylaxis in cardiac surgery as well as in the selection of empiric antibiotic therapy of DSWI. Methods: During the period May 2012-May 2013, 52 patients suffering from DSWI were treated at our institution. For every patient, deep tissue samples were obtained during surgical debridement procedures and submitted to microbiologic analysis. The frequency of and the time to occurrence of a DSWI was recorded, and baseline data, previous operative interventions, complications, and the technique used for soft tissue reconstruction, as well as the microbiologic results and individual risk factors, were documented. Results: There were 32 male patients (62%) and 20 female. The patients' age at the time of revision was a mean of 67 ± 11.5 years (range 35-83 years). There was bacterial growth in 31 cases (60%), the predominant species being S. epidermidis (20 patients; 65%). Extended antibiotic therapy was indispensable to controlling the infection. Conclusion: The local resistance patterns of antibiotics should have a greater influence on the standardized prophylaxis or empirical therapy of DSWI and need to be discussed specifically for this high-risk population. Because of its multi-resistance spectrum, S. epidermidis must be classified as a potential pathogen. In the cases reported here, extended antibiotic therapy was necessary to support wound healing and thus good patient outcomes.