Effect of time to onset on clinical features and prognosis of post-sternotomy mediastinitis

Infectious Mediastinitis: A Retrospective Cohort Study

Background

This study aimed to characterize the demographics, microbiology, management and treatment outcomes of mediastinitis according to the origin of the infection.

Methods

This retrospective observational study enrolled patients who had mediastinitis diagnosed according to the criteria defined by the Centers for Disease Control and Prevention and were treated in Strasbourg University Hospital, France, between 1 January 2010 and 31 December 2020.

Results

We investigated 151 cases, including 63 cases of poststernotomy mediastinitis (PSM), 60 cases of mediastinitis due to esophageal perforation (MEP) and 17 cases of descending necrotizing mediastinitis (DNM). The mean patient age (standard deviation) was 63 (14.5) years, and 109 of 151 patients were male. Microbiological documentation varied according to the origin of the infection. When documented, PSM cases were mostly monomicrobial (36 of 53 cases [67.9%]) and involved staphylococci (36 of 53 [67.9%]), whereas MEP and DNM cases were mostly plurimicrobial (38 of 48 [79.2%] and 8 of 12 [66.7%], respectively) and involved digestive or oral flora microorganisms, respectively. The median duration of anti-infective treatment was 41 days (interquartile range, 21-56 days), and 122 of 151 patients (80.8%) benefited from early surgical management. The overall 1-year survival rate was estimated to be 64.8% (95% confidence interval, 56.6%-74.3%), but varied from 80.1% for DNM to 61.5% for MEP.

Conclusions

Mediastinitis represents a rare yet deadly infection. The present cohort study exhibited the different patterns observed according to the origin of the infection. Greater insight and knowledge on these differences may help guide the management of these complex infections, especially with respect to empirical anti-infective treatments.

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.

Review on risk factors, classification, and treatment of sternal wound infection

Sternal wound infection (SWI) is the most common complication of the median sternal incision. The treatment time is long, and the reconstruction is difficult, which causes challenges for surgeons. Plastic surgeons were often involved too late in such clinical scenarios when previous empirical treatments failed and the wound damage was relatively serious. Accurate diagnosis and risk factors against sternal wound infection need to be in focus. Classification of different types of sternotomy complications post-cardiac surgery is important for specific categorization and management. Not familiar with this kind of special and complex wound, objectively increasing the difficulty of wound reconstruction. The purpose of this comprehensive review is to review the literature, introduce various SWI risk factors related to wound nonunion, various classification characteristics, advantages and disadvantages of various wound reconstruction strategies, to help clinicians understand the pathophysiological characteristics of the disease and choose a better treatment method.

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.

A new clinical classification and reconstructive strategy for post-sternotomy surgical site infection

Introduction

Post-sternotomy surgical site infection (SSI) is a serious complication of cardiovascular surgery. Here, we proposed a new clinical classification and reconstructive strategy for this condition.

Methods

A retrospective study based on medical records was performed on 100 consecutive cases requiring wound management by plastic surgeons for post-sternotomy SSI at Kobe University Hospital between January 2009 and December 2021. We classified 100 cases into four categories according to the anatomical invasiveness of the infection (type 1, superficial SSI; type 2, sternal osteomyelitis; type 3, mediastinitis; and type 4, aortic graft infection). The standard treatment plan comprised initial debridement, negative pressure wound therapy with continuous irrigation, and reconstructive surgery. Reconstructive methods and their outcomes (in-hospital mortality rate, follow-up period, and infection recurrence rate) were investigated for each SSI category.

Results

There were nine SSI cases in type 1, 28 in type 2, 25 in type 3, and 38 in type 4. The pectoralis major (PM) muscle advancement flap was mainly selected in types 1 and 2 (100 and 70.4%, respectively), while the omental flap or latissimus dorsi (LD) myocutaneous flaps were mainly selected in types 3 and 4 (77.3 and 81.8%, respectively) for reconstructive surgery. The in-hospital mortality rates for types 1, 2, 3, 4 were 44.4, 3.6, 12.0, and 15.8%, respectively. The mean follow-up periods for types 1, 2, 3, 4 were 542.8, 1514.5, 1154.5, and 831.1 days, respectively. Infection recurrence rates for types 1, 2, 3, 4 were 0, 11.5, 13.3, and 19.2%, respectively. All of these recurrent cases, except for 4 cases of type 4 that required surgical intervention, were treated with conservative wound management.

Conclusion

A volume-rich flap (omental or LD flap) was required to fill the dead space after debridement in mediastinitis (type 3) or aortic graft infection (type 4), whereas superficial SSI (type 1) or sternal osteomyelitis (type 2) received a less-invasive flap (PM muscle advancement flap). Our new classification method was based on the anatomical invasiveness of the infection, providing both a simple and easy diagnosis and definitive treatment strategy.

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A clinical classification for post-sternotomy surgical site infection is provided.

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The classification method is based on the anatomical invasiveness of the infection.

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It provides a simple and easy diagnosis and definitive treatment strategy.

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Reconstruction strategy was proposed to treat this condition.

Co-Management Reduces Mortality in Post-Sternotomy Mediastinitis

Background: Post-sternotomy mediastinitis (PSM) is one of the most feared complications of cardiac surgery. The impact of a multidisciplinary management approach on this pathology is yet unknown. Patients and Methods: A multidisciplinary approach based on a co-management model (CMM) of care was initiated in January 2018 because of the incorporation of a hospitalist unit on a cardiac surgery department. An observational retrospective cohort study was designed to evaluate the impact of the CMM of care compared to the standard model (SM) of care in patients diagnosed with PSM. Our primary and secondary outcomes were survival time and treatment failure rate (two or more surgical procedures needed to solve PSM or PSM-related death), respectively. Data related to patient death date were collected from the Spanish National Death Index. A multivariable Cox regression model was created using those variables believed to be clinically relevant. Results: Ninety-one patients developed PSM from January 2010 to June 2020. Regarding the pre-operative clinical status, surgical procedure, and PSM severity, both groups had similar baseline characteristics. Patients were followed for a mean of 27.54 ± 30.5 months. A total of 60.3% of the SM group and 11.1% of the CMM group (p < 0.001) died. Treatment failure occurred in 53 patients (72.6%) in the SM group versus 7 (38.6%) in the CMM group (p = 0.007). The CMM independently reduced overall mortality (hazard ratio [HR], 0.11; 95% confidence interval [CI]. 0.01-0.83) and treatment failure rate (HR, 0.01; 95% CI, 0.001-0.183). Gram-positive bacterial infection (HR, 3.73; 95% CI, .6-8.3), and complete osteosynthesis material removal (HR, 0.47; 95% CI, 0.24-0.91) also influenced mortality in our model. Conclusions: A co-management care model reduced overall mortality in patients diagnosed with post-sternotomy mediastinitis.

Analysis of Risk Factors for Sternal Wound Infection After Off-Pump Coronary Artery Bypass Grafting

Objective

To investigate the risk factors of deep sternal wound infection (DSWI) after off-pump coronary artery bypass grafting and its prevention and treatment strategy.

Methods

The clinical data of 465 patients who underwent OPCABG with a median chest incision were retrospectively analyzed. The patients were divided into the observation group (with DSWI, 32 cases) and the control group (without DSWI, 433 cases) according to the occurrence of DSWI. The preoperative, intraoperative, and postoperative clinical data relevant to DSWI were collected in both groups. The univariate and multivariate logistic regression analyses were adopted to analyze the risk factors for DSWI after OPCABG and investigateand its prevention and treatment strategy.

Results

DSWI occurred in 32 cases with an incidence of infection of 6.89%. There were 5 cases died in the observation group (with DSWI), the overall mortality rate was 1.07% and the intra-group mortality rate was 15.6%. There were 16 cases died in the control group (without DSWI) because of low cardiac output syndrome and multiple organ failure, the overall and intra-group mortality rates were 3.44% and 3.69% respectively. By analyzing the risk factors of DSWI between the two groups, the differences in age, body mass index (BMI), history of diabetes mellitus (DM), operation time, tracheal intubation time, time of stay in thecardiac care unit, blood transfusion (blood plasma)>800mL, blood transfusion (erythrocyte suspension)>6um, secondary thoracotomy were statistically significant between the observation and control groups (P < 0.05 in all).

Conclusion

Obesity, history of DM, prolonged operation time and tracheal intubation time, time of stay in CCU, utilization of blood product and secondary thoracotomy were DSWI independent risk factors after OPCABG.Some preventive measure should been implemented to reduce the incidence of DSWI, such as shorter operation time and tracheal intubation time, reducing the utilization of blood product.

Gram-negative bacteria as a cause of mediastinitis after cardiac surgery

PURPOSE OF REVIEW

Poststernotomy mediastinitis (PSM) remains a serious infection and is significantly associated with high morbidity, short-term and long-term mortality. Gram-negative bacteria (GNB) are an underestimated cause of PSM, and there is little information on the risk factors, prevention, diagnosis and management of GNB PSM.

RECENT FINDINGS

The pathogenesis of PSM is the result of a complex and multifactorial interplay between intraoperative wound contamination, host-related and surgical host factors but GNB are probably mostly translocated from other host site infections. GNB are frequent cause of PSM (18-38% of cases) and GNB PSM have shown to more frequently polymicrobial (20-44%). GNG PSM has shown to occur earlier than Gram-positive PSM. Early diagnosis is crucial to successful treatment. The management of PSM needs a combination of culture-directed antimicrobial therapy and an early extensive surgical debridement with either immediate or delayed closure of the sternal space. Antibiotic treatment choice and duration should be based on clinical evaluation, evolution of inflammatory markers, microbiological tests and imaging studies. Mortality has shown to be significantly higher with GNB PSM compared with other causes and the inappropriateness of initial antibiotic therapy may explain the worse outcome of GNB PSM.

SUMMARY

GNB PSM is usually undervalued in the setting of PSM and have shown to be a frequent cause of inappropriate treatment with adverse prognostic potential. There is a need for efforts to improve knowledge to prevent and adequately treat GNB PSM.

Use of Smart Technology for the Early Diagnosis of Complications After Cardiac Surgery: The Box 2.0 Study Protocol

BACKGROUND

Atrial fibrillation (AF), sternal wound infection, and cardiac decompensation are complications that can occur after cardiac surgery. Early detection of these complications is clinically relevant, as early treatment is associated with better clinical outcomes. Remote monitoring with the use of a smartphone (mobile health [mHealth]) might improve the early detection of complications after cardiac surgery.

OBJECTIVE

The primary aim of this study is to compare the detection rate of AF diagnosed with an mHealth solution to the detection rate of AF diagnosed with standard care. Secondary objectives include detection of sternal wound infection and cardiac decompensation, as well as assessment of quality of life, patient satisfaction, and cost-effectiveness.

METHODS

The Box 2.0 is a study with a prospective intervention group and a historical control group for comparison. Patients undergoing cardiac surgery at Leiden University Medical Center are eligible for enrollment. In this study, 365 historical patients will be used as controls and 365 other participants will be asked to receive either The Box 2.0 intervention consisting of seven home measurement devices along with a video consultation 2 weeks after discharge or standard cardiac care for 3 months. Patient information will be analyzed according to the intention-to-treat principle. The Box 2.0 devices include a blood pressure monitor, thermometer, weight scale, step count watch, single-lead electrocardiogram (ECG) device, 12-lead ECG device, and pulse oximeter.

RESULTS

The study started in November 2018. The primary outcome of this study is the detection rate of AF in both groups. Quality of life is measured with the five-level EuroQol five-dimension (EQ-5D-5L) questionnaire. Cost-effectiveness is calculated from a society perspective using prices from Dutch costing guidelines and quality of life data from the study. In the historical cohort, 93.9% (336/358) completed the EQ-5D-5L and patient satisfaction questionnaires 3 months after cardiac surgery.

CONCLUSIONS

The rationale and design of a study to investigate mHealth devices in postoperative cardiac surgery patients are presented. The first results are expected in September 2020.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03690492; http://clinicaltrials.gov/show/NCT03690492.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/16326.

Cellulose-Derived Absorbable Hemostatic Product as a Risk Factor for Mediastinitis after Cardiac Surgery

Background: We describe the management and control of an outbreak of mediastinitis in a cardiac surgery department. Method: We performed a retrospective cohort study of 87 patients who underwent coronary artery bypass grafting (CABG), valve replacement, or both during a five-month period with a higher than normal number of cases of post-operative mediastinitis. In addition to medical records review, a survey was conducted among surgeons to estimate the frequency of cellulose-derived absorbable hemostatic (CDAH) use. Results: Eleven patients (12.5%) developed mediastinitis during the period. None of them died, and the course of the infections was benign. No differences were found between the infected and non-infected patients regarding clinical or demographic characteristics. The rate of infection by surgeon ranged from 0 to 21.4%. (p = 0.38). We found a significant linear relation between the frequency of CDAH use and the risk of infection, from 3.3% to 22.6% (p = 0.024). Cultures of unused CDAHs were negative. Cessation of product use led to no new cases for the following year and to a mediastinitis rate <1% for the following 24 months. Conclusion: We identified a cluster of undesired clinical outcomes compatible with mediastinitis that added morbidity and associated cost, but not deaths, related to the use of CDAH as a hemostatic. These data suggest keeping the use of CDAH in cardiothoracic surgery to a minimum.

Prevention of deep sternal wound infection in cardiac surgery: a literature review

BACKGROUND

Deep sternal wound infection (DSWI) is a dreaded complication of cardiac surgery with considerable consequences in terms of mortality, morbidity and treatment costs. In addition to standard surgical site infection prevention guidelines, multiple specific measures in the prevention of DSWI have been developed and evaluated in the past decades. This review focuses on these specific measures to prevent DSWI.

METHODS

An extensive literature search was performed to assess interventions in the prevention of DSWI. Articles describing results of a randomized controlled trial were categorized by type of intervention. Results were yielded and, if possible, pooled.

RESULTS

From a total of 743 articles found, 48 randomized controlled trials were selected. Studies were divided into 12 categories, containing pre-, peri- and postoperative preventive measures. Specific measures shown to be effective were: antibiotic prophylaxis with a first-generation cephalosporin for at least 24 h, application of local gentamicin before chest closure, sternal closure with figure-of-eight steel wires, and postoperative chest support using a corset or vest.

CONCLUSION

This study identified several measures that prevent DSWI after cardiac surgery that are not frequently applied in current practice. It is recommended that the guidelines on prevention of surgical site infection in cardiac surgery should be updated.

Standard restrictive sternal precautions and modified sternal precautions had similar effects in people after cardiac surgery via median sternotomy ('SMART' Trial): a randomised trial

QUESTION

In people who have undergone cardiac surgery via median sternotomy, does modifying usual sternal precautions to make them less restrictive improve physical function, pain, kinesiophobia and health-related quality of life?

DESIGN

Two-centre, randomised, controlled trial with concealed allocation, blinded assessors and intention-to-treat analysis.

PARTICIPANTS

Seventy-two adults who had undergone cardiac surgery via a median sternotomy were included.

INTERVENTION

Participants were randomly allocated to one of two groups at 4 (SD 1) days after surgery. The control group received the usual advice to restrict their upper limb use for 4 to 6 weeks (ie, restrictive sternal precautions). The experimental group received advice to use pain and discomfort as the safe limits for their upper limb use during daily activities (ie, less restrictive precautions) for the same period. Both groups received postoperative individualised education in hospital and via weekly telephone calls for 6 weeks.

OUTCOME MEASURES

The primary outcome was physical function assessed by the Short Physical Performance Battery. Secondary outcomes included upper limb function, pain, kinesophobia, and health-related quality of life. Outcomes were measured before hospital discharge and at 4 and 12 weeks postoperatively. Adherence to sternal precautions was recorded.

RESULTS

There were no statistically significant differences in physical function between the groups at 4 weeks (MD 1.0, 95% CI -0.2 to 2.3) and 12 weeks (MD 0.4, 95% CI -0.9 to 1.6) postoperatively. There were no statistically significant between-group differences in secondary outcomes.

CONCLUSION

Modified (ie, less restrictive) sternal precautions for people following cardiac surgery had similar effects on physical recovery, pain and health-related quality of life as usual restrictive sternal precautions. Similar outcomes can be anticipated regardless of whether people following cardiac surgery are managed with traditional or modified sternal precautions.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry ANZCTRN12615000968572. [Katijjahbe MA, Granger CL, Denehy L, Royse A, Royse C, Bates R, Logie S, Nur Ayub MA, Clarke S, El-Ansary D (2018) Standard restrictive sternal precautions and modified sternal precautions had similar effects in people after cardiac surgery via median sternotomy ('SMART' Trial): a randomised trial. Journal of Physiotherapy 64: 97-106].

Deep sternal wound infection after cardiac surgery: a comparison of three different wound infection types and an analysis of antibiotic resistance

Background

Deep sternal wound infection (DSWI) is a severe complication following cardiac surgery. We compared epidemiology, clinical features, and microbiology of three types of DSWI and examined the antibiotic resistance in DSWI patients.

Methods

From 2011 to 2015, 170 adult post-cardiac surgery DSWI patients were recruited for this study and underwent the pectoralis major muscle flap transposition in our department.

Results

Of 170 adult patients with DSWI (mean age of 54 years), the majority (99 patients, 58.2%) had type II DSWI. The three types of DSWI patients showed significant differences in terms of gender, smoking history, chronic obstructive pulmonary disease (COPD), length of intensive care unit (ICU) stay, and hospitalization cost (P<0.05). The most common symptoms of DSWI patients were fever and wound dehiscence accompanied by purulent secretions. Types I and II DSWI were more frequently associated with hypoproteinemia and high leucocyte count (P<0.05). Microbiological diagnosis was available for 77 of 170 patients (45.3%). Of 157 pathogens detected, 87 (55.4%) species of gram negative bacilli were identified and most commonly were Pseudomonas aeruginosa (25.5%) and methicillin-susceptible Staphylococcus aureus (20.4%). However, no statistically significant microbiological differences among the three DSWI types were observed (P>0.05). Notably, P. aeruginosa isolates showed 100% resistance to cefazolin and cefuroxime. Meanwhile, the resistance rate of Acinetobacter baumannii isolates to commonly used antibiotics was greater than 70%, while resistance rates of staphylococcus to penicillin-G were 100% and to clindamycin were over 70%. No isolates were resistant to vancomycin, linezolid, and tigecycline.

Conclusions

Three types of DSWI exhibit differences in epidemiology and clinical features. P. aeruginosa and S. aureus are the most common pathogens in DSWI patients and antibiotic resistance is a serious concern in these patients. Therefore, prevention and treatment of DSWI should be closely tailored to clinical features, local microbiological characteristics, and resistance patterns of commonly encountered pathogens.

Surgical site infection with extended-spectrum β-lactamase-producing Enterobacteriaceae after cardiac surgery: incidence and risk factors

OBJECTIVE

To determine the incidence, microbiology and risk factors for sternal wound infection (SWI) with extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) following cardiac surgery.

METHODS

We performed a retrospective analysis between January 2006 and December 2015 of prospective surveillance of a cohort of patients with cardiac surgery at a single centre (Paris, France). SWI was defined as the need for reoperation due to sternal infection. All patients with an initial surgery under extracorporeal circulation and diagnosed with an SWI caused by Enterobacteriaceae isolates were included. We compared patients infected with at least one ESBL-PE with those with SWI due to other Enterobacteriaceae by logistic regression analysis.

RESULTS

Of the 11 167 patients who underwent cardiac surgery, 412 (3.7%) developed SWI, among which Enterobacteriaceae were isolated in 150 patients (36.5%), including 29 ESBL-PE. The main Enterobacteriaceae (n = 171) were Escherichia coli in 49 patients (29%) and Enterobacter cloacae in 26 (15%). Risk factors for SWI with ESBL-PE in the multivariate logistic regression were previous intensive care unit admission during the preceding 6 months (adjusted odds ratio (aOR) 12.2; 95% CI 3.3-44.8), postoperative intensive care unit stay before surgery for SWI longer than 5 days (aOR 4.6; 95% CI 1.7-11.9) and being born outside France (aOR 3.2; 95% CI 1.2-8.3).

CONCLUSIONS

Our results suggest that SWI due to ESBL-PE was associated with preoperative and postoperative unstable state, requiring an intensive care unit stay longer than the usual 24 or 48 postoperative hours, whereas being born outside France may indicate ESBL-PE carriage before hospital admission.

The Sternal Management Accelerated Recovery Trial (S.M.A.R.T) - standard restrictive versus an intervention of modified sternal precautions following cardiac surgery via median sternotomy: study protocol for a randomised controlled trial

Background

The routine implementation of sternal precautions to prevent sternal complications that restrict the use of the upper limbs is currently worldwide practice following a median sternotomy. However, evidence is limited and drawn primarily from cadaver studies and orthopaedic research. Sternal precautions may delay recovery, prolong hospital discharge and be overly restrictive. Recent research has shown that upper limb exercise reduces post-operative sternal pain and results in minimal micromotion between the sternal edges as measured by ultrasound. The aims of this study are to evaluate the effects of modified sternal precautions on physical function, pain, recovery and health-related quality of life after cardiac surgery.

Methods/design

This study is a phase II, double-blind, randomised controlled trial with concealed allocation, blinding of patients and assessors, and intention-to-treat analysis. Patients (n = 72) will be recruited following cardiac surgery via a median sternotomy. Sample size calculations were based on the minimal important difference (two points) for the primary outcome: Short Physical Performance Battery. Thirty-six participants are required per group to counter dropout (20%). All participants will be randomised to receive either standard or modified sternal precautions. The intervention group will receive guidelines encouraging the safe use of the upper limbs. Secondary outcomes are upper limb function, pain, kinesiophobia and health-related quality of life. Descriptive statistics will be used to summarise data. The primary hypothesis will be examined by repeated-measures analysis of variance to evaluate the changes from baseline to 4 weeks post-operatively in the intervention arm compared with the usual-care arm. In all tests to be conducted, a p value <0.05 (two-tailed) will be considered statistically significant, and confidence intervals will be reported.

Discussion

The Sternal Management Accelerated Recovery Trial (S.M.A.R.T.) is a two-centre randomised controlled trial powered and designed to investigate whether the effects of modifying sternal precautions to include the safe use of the upper limbs and trunk impact patients’ physical function and recovery following cardiac surgery via median sternotomy.

Trial registration

Australian and New Zealand Clinical Trials Registry identifier: ACTRN12615000968572. Registered on 16 September 2015 (prospectively registered).

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-1974-8) contains supplementary material, which is available to authorized users.

[Rational antibiotic treatment of mediastinitis]

Mediastinitis occurs as a severe complication of thoracic and cardiac surgical interventions and is the result of traumatic esophageal perforation, conducted infections or as a result of lymphogenic and hematogenic spread of specific infective pathogens. Treatment must as a rule be accompanied by antibiotics, whereby knowledge of the spectrum of pathogens depending on the pathogenesis is indispensable for successful antibiotic therapy. Polymicrobial infections with a high proportion of anaerobes are found in conducted infections of the mediastinum and after esophageal perforation. After cardiac surgery Staphylococci are the dominant pathogens and a nasal colonization with Staphylococcus aureus seems to be a predisposing risk factor. Fungi are the predominant pathogens in immunocompromised patients with consumptive underlying illnesses and can cause acute or chronic forms with granulomatous inflammation. Resistant pathogens are increasingly being found in high-risk patient cohorts, which must be considered for a calculated therapy. For calculated antibiotic therapy the administration of broad spectrum antibiotics, mostly beta-lactams alone or combined with metronidazole is the therapy of choice for both Gram-positive and Gram-negative bacteria inclusive of anaerobes. For patients at risk, additional antibiotic classes with a spectrum against methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) can be administered. Increasing rates of multidrug-resistant Gram-negative bacteria (e.g. Enterobacteriaceae) and non-fermenting bacteria (e.g. Pseudomonas and Acinetobacter) in individual cases necessitates the use of polymyxins (e.g. colistin), new tetracyclines (e.g. glycylglycines) and newly developed combinations of beta-lactams and beta-lactam inhibitors. For treatment of fungal infections (e.g. Candida, Aspergillus and Histoplasma) established and novel azoles, amphotericin B and echinocandins seem to be successful; however, detection of Candida, particularly in mixed infections does not always necessitate treatment. Mediastinitis is still a severe infectious disease with a high mortality, which necessitates an early and broad spectrum antibiotic therapy; however, with respect to optimal duration of therapy and selection of antibiotics, data from good quality comparative studies are lacking.

Sternal Wound Infection after Cardiac Surgery: Management and Outcome

Background

Sternal Wound Infection (SWI) is a severe complication after cardiac surgery. Debridement associated with primary closure using Redon drains (RD) is an effective treatment, but data on RD management and antibiotic treatment are scarce.

Methods

We performed a single-center analysis of consecutive patients who were re-operated for SWI between 01/2009 and 12/2012. All patients underwent a closed drainage with RD (CDRD). Patients with endocarditis or those who died within the first 45 days were excluded from management analysis. RD fluid was cultured twice weekly. Variables recorded were clinical and biological data at SWI diagnosis, severity of SWI based on criteria for mediastinitis as defined by the Centers for Disease Control (CDC), antibiotic therapy, RD management and patient’s outcome.

Results

160 patients developed SWI, 102 (64%) fulfilled CDC criteria (CDC+) and 58 (36%) did not (CDC- SWI). Initial antibiotic treatment and surgical management were similar in CDC+ and CDC- SWI. Patients with CDC+ SWI had a longer duration of antibiotic therapy and a mortality rate of 17% as compared to 3% in patients with CDC- SWI (p = 0.025). Rates of superinfection (10% and 9%) and need for second reoperation (12% and 17%) were similar. Failure (death or need for another reoperation) was associated with female gender, higher EuroScore for prediction of operative mortality, and stay in the ICU.

Conclusion

In patients with SWI, initial one-stage surgical debridement with CDRD is associated with favorable outcomes. CDC+ and CDC- SWI received essentially the same management, but CDC+ SWI has a more severe outcome.

Factors associated with methicillin-resistant coagulase-negative staphylococci as causing organisms in deep sternal wound infections after cardiac surgery

Established preoperative antibiotic prophylaxis in cardiac surgery is ineffective against methicillin-resistant coagulase-negative staphylococci (CoNS). This case-control study aimed to determine factors predicting deep sternal wound infections due to methicillin-resistant CoNS. All cardiac surgery patients undergoing sternotomy between June 2009 and March 2013 prospectively documented in a Swiss tertiary care center were included. Among 1999 patients, 82 (4.1%) developed deep sternal wound infection. CoNS were causal in 36 (44%) patients, with 25/36 (69%) being methicillin resistant. Early reintervention for noninfectious causes (odds ratio (OR) 4.3; 95% confidence interval (CI) 1.9-9.5) was associated with methicillin-resistant CoNS deep sternal wound infection. Among CoNS deep sternal wound infection, perioperative antimicrobial therapy (p 0.002), early reintervention for noninfectious causes (OR 7.9; 95% CI 0.9-71.1) and time between surgery and diagnosis of infection over 21 days (OR 10.8; 95% CI 1.2-97.8) were associated with methicillin resistance. These findings may help to better tailor preoperative antimicrobial prophylaxis.

Clinical evolution of mediastinitis in patients undergoing adjuvant hyperbaric oxygen therapy after coronary artery bypass surgery

Objective:

To evaluate the use of hyperbaric oxygen therapy as an adjunctive treatment in mediastinitis after coronary artery bypass surgery.

Methods:

This is a retrospective descriptive study, performed between October 2010 and February 2012. Hyperbaric oxygen therapy was indicated in difficult clinical management cases despite antibiotic therapy.

Results:

We identified 18 patients with mediastinitis during the study period. Thirty three microorganisms were isolated, and polymicrobial infection was present in 11 cases. Enterobacteriaceae were the most prevalent pathogens and six were multi-resistant agents. There was only 1 hospital death, 7 months after the oxygen therapy caused by sepsis, unrelated to hyperbaric oxygen therapy. This treatment was well-tolerated.

Conclusion:

The initial data showed favorable clinical outcomes.

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.

Primary closure using Redon drains for the treatment of post-sternotomy mediastinitis

OBJECTIVES

Post-sternotomy mediastinitis is a severe complication of open heart surgery resulting in prolonged hospital stay and increased mortality. Vacuum-assisted closure is commonly used as treatment for post-sternotomy mediastinitis, but has some disadvantages. Primary closure over high vacuum suction Redon drains previously has shown to be an alternative approach with promising results. We report our short- and long-term results of Redon therapy-treated mediastinitis.

METHODS

We performed a retrospective analysis of 124 patients who underwent primary closure of the sternum over Redon drains as treatment for post-sternotomy mediastinitis in Amphia Hospital (Breda, Netherlands) and St. Antonius Hospital (Nieuwegein, Netherlands). Patient characteristics, preoperative risk factors and procedure-related variables were analysed. Duration of therapy, hospital stay, treatment failure and mortality as well as C-reactive protein and blood leucocyte counts on admission and at various time intervals during hospital stay were determined.

RESULTS

Mean age of patients was 68.7 ± 11.0 years. In 77.4%, the primary surgery was coronary artery bypass grafting. Presentation of mediastinitis was 15.2 ± 9.8 days after surgery. Duration of Redon therapy was 25.9 ± 18.4 days. Hospital stay was 32.8 ± 20.7 days. Treatment failure occurred in 8.1% of patients. In-hospital mortality was 8.9%. No risk factors were found for mortality or treatment failure. The median follow-up time was 6.6 years. One- and 5-year survivals were 86 and 70%, respectively.

CONCLUSIONS

Primary closure using Redon drains is a feasible, simple and efficient treatment modality for post-sternotomy mediastinitis.

Hyperbaric oxygen therapy as an adjunctive treatment for sternal infection and osteomyelitis after sternotomy and cardiothoracic surgery

Purpose

A retrospective study to evaluate the effect of hyperbaric oxygen (HBO2) therapy on sternal infection and osteomyelitis following median sternotomy.

Materials and methods

A retrospective analysis of patients who received sternotomy and cardiothoracic surgery which developed sternal infection and osteomyelitis between 2002 and 2009. Twelve patients who received debridement and antibiotic treatment were selected, and six of them received additional HBO2 therapy. Demographic, clinical characteristics and outcome were compared between patients with and without HBO2 therapy.

Results

HBO2 therapy did not cause any treatment-related complication in patients receiving this additional treatment. Comparisons of the data between two study groups revealed that the length of stay in ICU (8.7 ± 2.7 days vs. 48.8 ± 10.5 days, p < 0.05), duration of invasive (4 ± 1.5 days vs. 34.8 ± 8.3 days, p < 0.05) and non-invasive (4 ± 1.9 days vs. 22.3 ± 6.2 days, p < 0.05) positive pressure ventilation were all significantly lower in patients with additional HBO2 therapy, as compared to patients without HBO2 therapy. Hospital mortality was also significantly lower in patients who received HBO2 therapy (0 case vs. 3 cases, p < 0.05), as compared to patients without the HBO2 therapy.

Conclusions

In addition to primary treatment with debridement and antibiotic use, HBO2 therapy may be used as an adjunctive and safe treatment to improve clinical outcomes in patients with sternal infection and osteomyelitis after sternotomy and cardiothoracic surgery.