Financial Impact of Deep Sternal Wound Infections After Coronary Surgery: A Microcosting Analysis.

INTRODUCTION: Deep sternal wound infections (DSWI) are so serious and costly that hospital services continue to strive to control and prevent these outcomes. Microcosting is the more accurate approach in economic healthcare evaluation, but there are no studies in this field applying this method to compare DSWI after isolated coronary artery bypass grafting (CABG). This study aims to evaluate the incremental risk-adjusted costs of DSWI on isolated CABG. METHODS: This is a retrospective, single-center observational cohort study with a propensity score matching for infected and non-infected patients to compare incremental risk-adjusted costs between groups. Data to homogeneity sample was obtained from a multicentric database, REPLICCAR II, and additional sources of information about costs were achieved with the electronic hospital system (Si3). Inflation variation and dollar quotation in the study period were corrected using the General Market Price Index. Groups were compared using analysis of variance, and multiple linear regression was performed to evaluate the cost drivers related to the event. RESULTS: As expected, infections were costly; deep infection increased the costs by 152% and mediastinitis by 188%. Groups differed among hospital stay, exams, medications, and multidisciplinary labor, and hospital stay costs were the most critical cost driver. CONCLUSION: In summary, our results demonstrate the incremental costs of a detailed microcosting evaluation of infections on CABG patients in São Paulo, Brazil. Hospital stay was an important cost driver identified, demonstrating the importance of evaluating patients' characteristics and managing risks for a faster, safer, and more effective discharge.

Cost-Effectiveness of Negative Pressure Incision Management System in Cardiac Surgery.

BACKGROUND: Sternal wound infections (SWIs) can be a devastating long-term complication with significant morbidity and health care cost. The purpose of this analysis was to evaluate the cost-effectiveness of negative pressure incision management systems (NPIMS) in cardiac surgery. MATERIALS AND METHODS: All cardiac surgery cases at an academic hospital with risk scores available (2009-2017) were extracted from an institutional database (n = 4455). Patients were stratified by utilization of NPIMS, and high risk was defined as above the median. Costs included infection-related readmissions and were adjusted for inflation. Multivariable regression models assessed the risk-adjusted cost of SWI and efficacy of NPIMS use. Cost-effectiveness was modeled using TreeAge Pro using institutional results. RESULTS: The rate of deep SWI was 0.9% with an estimated cost of $111,175 (P < 0.0001). The rate of superficial SWI was 0.8% at a cost of $7981 (P = 0.08). Risk-adjusted NPIMS use was not significantly associated with reduced SWI (OR 1.2, P = 0.62) and thus not cost-effective. However, in the high-risk cohort with an OR 0.84 (P = 0.72) and SWI rate of 2.3%, NPIMS use cost $205 per patient with an incremental cost-effectiveness ratio of $179,092. Therefore, NPIMS is estimated to be cost-effective with a deep SWI rate over 1.3% or improved efficacy (OR < 0.83). CONCLUSIONS: SWIs are extremely expensive complications with estimates of $111,175 for deep yet only $7981 for superficial. Although NPIMS was not cost-effective for SWI prevention as currently utilized, a protocol for use on patients with a higher risk of sternal infection could be cost-effective.

Different Nuss procedures and risk management for pectus excavatum after surgery for congenital heart disease.

PURPOSE: In Nuss procedure for pectus excavatum (PE) after surgery for congenital heart disease (CHD), retrosternal adhesion may increase the risk of cardiac injury. This study aimed to explore different Nuss procedures and their implications for reducing the incidence of serious complications and improving surgical safety. METHODS: We retrospectively reviewed 49 cases (29 male and 20 female) of Nuss procedures for PE after surgery for CHD that were performed between April 2003 and December 2016. The median age was 5.8 years (range, 3.0-17.9), and the median Haller index was 4.6 (3.2-17.7). All patients were evaluated on their cardiac function and severity of PE by echocardiography and computed tomography scan, respectively. Three surgical procedures were used. Perioperative conditions were analyzed, including CHD type, interval between two operations, blood loss, operation time, hospital stay, complications, and postoperative results. RESULTS: All 49 cases were completed successfully. Fourteen cases (28.6%) involved the standard three-incision thoracoscopic Nuss procedure, 30 cases (61.2%) involved the Nuss procedure assisted by a median sternum incision, and 5 cases (10.2%) involved the Nuss procedure with sternal suspension. The median interval between the CHD surgery and Nuss procedure was 4.0 years (0.5-12.0). The median blood loss was 2.0 mL (1.0-150.0 mL). The median operation time was 45.0 min (27.0-230.0), and the median hospital stay was 6.0 days (5.0-9.0). Three patients (6.1%) experienced severe surgical complications: 2 experienced a rupture of the right atrium and 1 had pericardial injury. Patients were followed up for 7-120 months after surgery. The postoperative results were excellent in 46 cases (93.9%) and good in 3 (6.1%). Twenty-four of the 49 patients have had their bars removed. The median time for bar removal was 36.0 months (24.0-47.0). The outcome after bar removal surgery was excellent in 20 cases and good in 4. CONCLUSIONS: Patients may develop PE or worsening of preexisting PE after open heart surgery for CHD. Surgery for PE can still be performed by the standard Nuss technique without increasing the risk of cardiac injury for the patients that have had interventional cardiology procedures for CHD previously. However, the risk of cardiac injury during the Nuss procedure dramatically increases due to retrosternal adhesions that develop after open heart surgery for CHD. In our experience, the Nuss procedure is safe and feasible after open heart surgery for CHD when performed by an experienced pectus surgeon using an individualized surgical plan for each patient. TYPE OF STUDY: Retrospective study. LEVEL OF EVIDENCE: Level IV.

Rigid Plate Fixation Versus Wire Cerclage: Patient-Reported and Economic Outcomes From a Randomized Trial.

BACKGROUND: In a multicenter randomized trial, sternal closure after cardiac operations using rigid plate fixation (RPF) compared with wire cerclage (WC) resulted in improved sternal healing, reduced sternal complications, and was cost neutral at 6 months. Additional secondary end points are presented from this trial. METHODS: Twelve United States centers randomized 236 patients to RPF (n = 116) or WC (n = 120). Patient-reported outcomes measures, including pain, function, and quality of life scores, were assessed through 6 months and correlated to computed tomography-derived sternal healing scores using logistic regression. Cost analysis through 90 days was performed to mimic bundled care models. RESULTS: All patient-reported outcomes measures were numerically better in RPF patients than in WC patients at all assessments. RPF resulted in more patients reporting no sternal pain after coughing at 3 weeks (41.1% vs 19.6%; p = 0.001) and 6 weeks (54.5% vs 35.1%; p = 0.005) and at rest at 6 weeks (74.1% vs 58.8%; p = 0.02) and 3 months (87.6% vs 75.9%; p = 0.03) compared with WC. Better sternal healing scores correlated to having no sternal pain at rest (odds ratio, 1.6; 95% confidence interval, 1.2 to 2.2; p = 0.002) and after coughing (odds ratio, 1.6; 95% confidence interval, 1.2 to 2.2; p = 0.0007). RPF resulted in improvements in the 36-Item Short Form Health Survey quality of life scores at 3 weeks (53.5 ± 8.7 vs 50.5 ± 10.4; p = 0.03), 6 weeks (45.3 ± 8.4 vs 42.7 ± 8.4; p = 0.03), and 6 months (56.4 ± 6.8 vs 53.9 ± 9.0; p = 0.04) compared with WC. Through 90 days, RPF compared with WC was $1,888 less (95% confidence interval, -$8,889 to $4,273; p = 0.52). CONCLUSIONS: In patients undergoing sternal closure after median sternotomy, RPF compared with WC resulted in reduced sternal pain, improved upper extremity function, and similar total 90-day costs.

A New Device for Securing Sternal Wires After Median Sternotomy: Biomechanical Study and Retrospective Clinical Assessment.

OBJECTIVE: Morbidity due to sternotomy continues to be a significant clinical problem. Poor approximation of the sternum may lead to complications such as sternal dehiscence, infection, and pain. A device to assist in tensioning and twisting standard steel wires during sternal closure has been developed (TORQ sternal closure device). Manually tightened interrupted wire closures were compared with those tightened and secured with the aid of the device. Performance of the device was assessed clinically. METHODS: Four cardiovascular surgeons performed manual and device-assisted closures on a biofidelic model. Closure force was measured to determine the residual force and its intraoperator variation. A retrospective review of patients treated before and after the introduction of the device was conducted. Predicted and actual outcomes were compared for the two groups (manual closure and device-assisted closure). RESULTS: Biomechanical testing measured a 75% increase in residual closure force (P < 0.001) and a significant reduction in the variability of the closure force (P = 0.045) for device-assisted closures compared with manual closures. In the retrospective study, 3 of 173 manually closed patients had sterile sternal dehiscence and 1 of 173 had a deep sternal wound infection. In the device closure group, 2 of 127 had a sterile sternal dehiscence and no deep sternal wound infections were reported. No other device-related serious adverse events were reported. CONCLUSIONS: Biomechanical data showed stronger, more consistent closure forces with the device. The retrospective data attest to the performance of the device.

Randomized, multicenter trial comparing sternotomy closure with rigid plate fixation to wire cerclage.

OBJECTIVE: To evaluate sternal healing, complications, and costs after sternotomy closure with rigid plate fixation or wire cerclage. METHODS: This prospective, single-blinded, multicenter trial randomized 236 patients at 12 US centers at the time of sternal closure to either rigid plate fixation (n = 116) or wire cerclage (n = 120). The primary endpoint, sternal healing at 6 months, was evaluated by a core laboratory using computed tomography and a 6-point scale (greater scores represent greater healing). Secondary endpoints included sternal complications and costs from the time of sternal closure through 6 months. RESULTS: Rigid plate fixation resulted in better sternal healing scores at 3 (2.6 ± 1.1 vs 1.8 ± 1.0; P < .0001) and 6 months (3.8 ± 1.0 vs 3.3 ± 1.1; P = .0007) and greater sternal union rates at 3 (41% [42/103] vs 16% [16/102]; P < .0001) and 6 months (80% [81/101] vs 67% [67/100]; P = .03) compared with wire cerclage. There were fewer sternal complications through 6 months with rigid plate fixation (0% [0/116] vs 5% [6/120]; P = .03) and a trend towards fewer sternal wound infections (0% [0/116] vs 4.2% [5/120]; P = .06) compared with wire cerclage. Although rigid plate fixation was associated with a trend toward greater index hospitalization costs ($23,437 vs $20,574; P = .11), 6-month follow-up costs tended to be lower ($9002 vs $13,511; P = .14). As a result, total costs from randomization through 6 months were similar between groups ($32,439 vs $34,085; P = .61). CONCLUSIONS: Sternotomy closure with rigid plate fixation resulted in significantly better sternal healing, fewer sternal complications, and no additional cost compared with wire cerclage at 6 months after surgery.

The Impact of Deep Sternal Wound Infection on Mortality and Resource Utilization: A Population-based Study.

BACKGROUND: Recent national infection control efforts have been directed at reducing postsurgical infection rates, related morbidity, and cost. We sought to evaluate population-level rates of deep sternal wound infection (DSWI) after cardiac surgery, associated mortality, and resource use compared to patients undergoing cardiac surgery without postoperative DSWI relative to historical trends. METHODS: We analyzed the MarketScan ® Commercial Claims Databases from 2009 to 2013 to identify adult patients who developed DSWI after open cardiac surgery. Patients with and without DSWI were compared. The outcomes of interest included 30-day, 90-day, and 1-year in-hospital mortality. Utilization outcomes, including total hospital days and inpatient costs, were calculated in the time period from the index cardiac surgery through 90 days after DSWI diagnosis. RESULTS: In this cohort, 176,537 patients underwent one or more cardiac surgery procedures. DSWI occurred in 2835 (1.6 %) patients. One-year mortality for patients with DSWI was 10.7 versus 2.5 % (P < 0.001) in patients without DSWI. Mean hospital days in patients with DSWI were 33 versus 9 days for patients without DSWI (P < 0.001). Mean cost for patients with DSWI was greater than 2.5 times that of patients without DSWI ($211,478 vs $82,089, P < 0.001). CONCLUSIONS: Treatment of DSWI results in substantial morbidity, mortality, and excess cost for treating facilities. The rates of DSWI have not decreased dramatically over the last 10-20 years. Thus, more attention needs to be focused toward understanding treatment variation that exists in patients diagnosed with DSWI.

Delayed Sternal Closure After Continuous Flow Left Ventricle Assist Device Implantation: Analysis of Risk Factors and Impact on Outcomes and Costs.

Patient and institutional factors predictive of delayed sternal closure (DSC) practice and its impact on clinical and cost outcomes when compared with primary sternal closure (PSC) following continuous-flow left ventricular assist device (CF-LVAD) implantation were examined. Statewide Society of Thoracic Surgeons and hospital cost data on CF-LVADs implanted were analyzed. Between January 2007 and December 2013, 558 CF-LVADs were implanted (PSC = 464, 83.2%; DSC = 94, 16.8%). Among the six institutions implanting CF-LVADs, DSC practice ranged from 3.1% to 37.8%. Compared with PSC, the DSC group had higher body mass index (BMI), renal failure, anemia, IIb/IIIa inhibitor use, emergency surgery, and extracorporeal membrane oxygenation (ECMO) support. Delayed sternal closure patients had significantly longer bypass time (139 ± 63 min vs. 107.6 ± 42 min) and higher use of intraoperative blood products (82% vs. 69%) and right ventricular assist device (RVAD) support (4.3% vs. 0.2%). Postoperative morbidities and mortality (23.4% vs. 6.5%; p ≤ 0.0001) were higher in the DSC group compared with PSC. Mean hospital costs for DSC were higher than PSC ($249,144 ± 123,273 vs. $155,915 ± 95,032; p ≤ 0.0001). Multivariate predictors of DSC include institution with higher DSC practice, preoperative ECMO support, use of IIb/IIIa inhibitors, tricuspid valve surgery, and intraoperative red blood cell transfusion. Delayed sternal closure was an independent risk factor for postoperative mortality, odds ratio 3.0 (1.2-7.2).

Cost analysis of gentamicin-impregnated collagen sponges in preventing sternal wound infection post cardiac surgery.

OBJECTIVE: The use of antibiotic-impregnated sponges (Collatamp) during cardiac surgery is controversial. We analysed the cost-effectiveness of its selective use in patients at high-risk of sternal wound infection (SWI). METHOD: Postoperative costs were analysed in two groups of patients undergoing heart surgery between 2011 and 2013: those with SWI (group 1) and in high-risk patients without SWI (group 2). The potential cost of gentamicin-impregnated collagen sponges (GCS) use in high-risk patients was compared with our current practice. RESULTS: We identified 1,251 patients with at least one recognised risk factor for developing SWI in this period. Of these, 18 developed SWI (incidence 1.4%). The median postoperative cost per patient without SWI was £9,617. The additional cost per patient incurred by SWI was £4,860.75. The annual additional cost for treating patients with SWI was £43,749. With a 50% reduction in SWI, the annual additional cost of treating these patients would be reduced to £21,873. The cost of GCS is £80 per patient. Adding this to £21,873 gives a potential total cost of £71,913 in the treated high-risk cohort. CONCLUSION: In our practice the annual cost of treating SWI in high-risk patients without use of GCS is lower than the annual cost of using GCS in all high-risk patients (£43,749 versus £71,913) if it produces a 50% reduction in SWI. The reduction in the incidence of SWI poses no economic benefit when the cost of the product is factored in.

Assessment of the Association of Bilateral Internal Thoracic Artery Skeletonization and Sternal Wound Infection After Coronary Artery Bypass Grafting.

BACKGROUND: Skeletonization is a technique of bilateral internal thoracic artery (BITA) harvest that preserves sternal blood flow. We sought to identify the relationship of skeletonization and sternal wound infection in a population undergoing BITA harvest. METHODS: Demographics and outcomes were recorded from patients undergoing coronary artery bypass graft surgery with BITA using either skeletonized (n = 531) or nonskeletonized (n = 970) techniques. The primary outcome was total infection. Propensity scores analysis as well as univariable and multivariable analysis was performed to determine the effect of skeletonization in the total cohort and in each sex. RESULTS: Although patients undergoing skeletonized BITA had a lower body mass index, they were significantly older, with a higher proportion of women, diabetes mellitus, urgent or emergent surgery, renal failure, vascular and lung disease, and lower preoperative hemoglobin. There was a significant effect of skeletonization in decreasing total infection incidence (odds ratio [OR] 0.606, 95% confidence interval [CI]: 0.383 to 0.959, p = 0.032). The effect of skeletonization on total infection in men was more prominent (OR 0.466, 95% CI: 0.290 to 0.870), whereas there was no effect in women (OR 0.887, 95% CI: 0.441 to 1.786). Multivariable analysis confirmed that skeletonization was protective (OR 0.606, 95% CI: 0.383 to 0.957, p = 0.032). Other factors associated included being female (OR 3.327, 95% CI: 2.080 to 5.322, p < 0.001), insulin-dependent diabetes mellitus (OR 2.638, 95% CI: 1.506 to 4.624, p = 0.001), peripheral vascular disease (OR 2.101, 95% CI: 1.247 to 3.539, p = 0.005), increased body mass index (OR 1.100, 95% CI: 1.054 to 1.149, p < 0.001), and decreased preoperative hemoglobin (OR 0.984, 95% CI: 0.972 to 0.997, p = 0.013). CONCLUSIONS: Skeletonization is associated with a significant protective effect with regard to sternal infection after coronary artery bypass graft surgery with BITA. Being female is a major risk factor for infection, and the risk is not modified significantly with a strategy of skeletonization in women.

Nitinol flexigrip sternal closure system and standard sternal steel wiring: insight from a matched comparative analysis.

OBJECTIVE: We sought to assess the efficiency of two different sternal closure techniques in preventing sternal wound instability in high-risk patients. MATERIALS AND METHODS: Between January 2009 and February 2012, 2068 consecutive cardiac patients were prospectively collected in our database. The 561 patients in whom the thermoreactive nitilium clips (Flexigrip) have been used (group A) were matched 1 : 1 with 561 patients who received a standard parasternal wiring technique (group B) on 10 available risk factors known to affect sternal wound healing (age, age >75 years, sex, diabetes mellitus, cardiac procedure, obesity, re-intervention, cross-clamp, and total operative times). The study was completed with a cost analysis. RESULTS: The two groups were well matched, although different for bilateral internal thoracic harvesting, chronic obstructive pulmonary disease, renal insufficiency, and congestive heart failure, which were significantly more frequent in group A. At 30 days of follow-up, the association of wound complication and sternal instability was significantly less frequent in group A versus group B (0.2 versus 1.6%) (P = 0.04). Overall incidence of sternal wound complication was lower in group A (2 versus 3.5%) (P = 0.28). In the presence of wound infection, a sternal wound instability was never observed in group A (P = 0.06). Overall costs were €8,701,854 and €9,243,702 in groups A and B, respectively; thus the Flexigrip closure technique offered a €541,848 cost saving. CONCLUSIONS: Flexigrip use in high-risk patients showed a lower incidence of sternal wound instability with no need for sternal re-wiring in any case, even in the presence of wound infection.

Technical innovation in minimally invasive repair of pectus excavatum.

The aim of study was to introduce technical innovation of MIRPE which reduces the risk of cardiac injury. Modification of MIRPE method with semiflexible thoracoscope and sternum elevating technique has been used. Volkmann bone hook has been inserted percutaneously to the sternum. The hook elevates the sternum forward and enlarges the retrosternal space for safer passage of thoracoscopically guided introducer. Using semiflexible thoracoscope allows better view from various angles via one site of insertion. During the period 2005-2012, the MIRPE was performed on 29 girls and 151 boys; the mean age at the time of surgery was 15.9 years (range 13-18.7 years). The mean Haller index was 4.7 (range 2.7-20.5). The most common complication was pneumothorax (3.3 %) and the incidence of bar displacement was 2 %. The most serious complication was cardiac perforation when inserting Lorenz introducer. This occurred in a 16-year-old girl; she required urgent sternotomy with right atrial repair and recovered well. External elevation of sternum with the hook was used since this case. Subsequent 113 patients underwent surgery without any serious complications. Technical innovation using semiflexible thoracoscope and hook elevation of the sternum reduces the risk of cardiac injury. The hook opens the anterior mediastinum space effectively and makes the following dissection relatively safe and straightforward.

Assessment of sternal closure using titanium plate.

INTRODUCTION: The use of plates and screws for more rigid fixation of the sternum, without maintaining contact between the upper portion of the sternum and mediastinum. The present study seeks new choice of plate with a significant difference, the same does not need to be removed in order to proceed to open when necessary sternal emerging opening of the bone. OBJECTIVE: The current study aims to evaluate the efficacy and safety of this procedure. METHODS: To this end, we selected ten patients with coronary artery disease have shown no significant risk factors for mediastinitis. The surgery was thus performed in the usual way that all patients with coronary artery disease surgeries are done at the institution. Only at the time of sternal closure is that there was a change, with the combination of steel wires and plates. RESULTS: All cases had sternal closure properly with good outcome in the medium term. CONCLUSION: The use of plates ENGIMPLAN proved safe and effective for sternal closure.

Assessment of sternal closure using titanium plate / Avaliação do fechamento esternal com placa de titânio

INTRODUCTION: The use of plates and screws for more rigid fixation of the sternum, without maintaining contact between the upper portion of the sternum and mediastinum. The present study seeks new choice of plate with a significant difference, the same does not need to be removed in order to proceed to open when necessary sternal emerging opening of the bone. OBJECTIVE: The current study aims to evaluate the efficacy and safety of this procedure. METHODS: To this end, we selected ten patients with coronary artery disease have shown no significant risk factors for mediastinitis. The surgery was thus performed in the usual way that all patients with coronary artery disease surgeries are done at the institution. Only at the time of sternal closure is that there was a change, with the combination of steel wires and plates. RESULTS: All cases had sternal closure properly with good outcome in the medium term. CONCLUSION: The use of plates ENGIMPLAN proved safe and effective for sternal closure.

INTRODUÇÃO: A utilização de placas e parafuso para a mais rígida fixação do esterno, sem manter contato entre a porção superior do esterno e o mediastino. O estudo atual busca nova opção de placa, com um diferencial importante; a mesma não precisa ser retirada para que se proceda à abertura esternal em caso de necessidade emergente de abertura do osso. OBJETIVO: O presente estudo tem por objetivo avaliar a eficácia e a segurança de tal procedimento. MÉTODOS: Para tal, foram selecionados dez pacientes portadores de doença arterial coronária que não apresentassem importantes fatores de risco para mediastinite. As cirurgias foram, portanto, realizadas da maneira habitual, a todas os procedimentos em portadores de coronariopatias são feitas na Instituição. Somente no momento do fechamento esternal é que houve uma modificação, com a associação de fios de aço e placas. RESULTADOS: Todos os casos apresentaram fechamento esternal de forma adequada com boa evolução a médio prazo. CONCLUSÃO: O emprego das placas ENGIMPLAN se mostrou seguro e eficaz no fechamento esternal.

Nitinol flexigrip sternal closure system and chest wound infections: insight from a comparative analysis of complications and costs.

BACKGROUND: We sought to assess the efficiency of two different sternal closure techniques in preventing sternal wound complications (SWC). A cost analysis was also considered. METHODS: Between January 2008 and April 2010, 1,644 consecutive cardiac surgery patients who underwent cardiac surgery in our institute were prospectively collected. A total of 1,072 patients received a standard parasternal wiring technique (group A), and 572 patients received a new method of sternal closure based on the use of thermoreactive nitillium clips (Flexigrip; Praesidia SRL, Bologna, Italy [group B]). We investigated, by a propensity matched analysis, whether the use of standard or nitinol clip closure would impact on sternal wound outcome. RESULTS: In all, 464 patients of each group were matched for 17 available risk factors. Overall incidence of SWC was significantly higher in group A (4.1% versus 1.7%; p=0.03). Sternal surgical revision to treat a thoracic instability was required in a significantly higher number of patients in group A (9 patients, 1.9%) and in none of group B (p=0.004). The incidence of sternal instability, secondary to wound infection, was significantly lower in group B (p=0.05). Overall costs were €7,407,296 and €6,896,432 in group A and group B, respectively. Thus, nitinol clip closure technique offered a €510,864 cost saving compared with standard steel wiring technique. CONCLUSIONS: The Flexigrip assured a lower incidence of SWC. The use of the nitinol clip favored an improved sternal closure technique preventing mediastinitis. Additionally, the nitinol clip system proved to be cost effective in cardiac surgery.

Diagnostic accuracy of modified transoesophageal echocardiography for pre-incision assessment of aortic atherosclerosis in cardiac surgery patients.

BACKGROUND: Epiaortic ultrasound scanning (EUS) is regarded as the reference standard for detecting atherosclerosis in the ascending aorta (AA). Combined with appropriate surgical modifications, EUS use can significantly reduce the incidence of postoperative stroke when detecting severe AA atherosclerosis. A recently introduced modification of conventional transoesophageal echocardiography (TOE), known as the A-View method, has proven capable of inspecting the distal AA. The objective of this study was to quantify the diagnostic accuracy of modified TOE in assessing atherosclerosis of the distal AA. METHODS: After approval by the institutional medical ethical committee and after obtaining written informed consent, 465 consecutive patients above 65 yr old, undergoing elective cardiac surgery with a median sternotomy, were included. The study followed a cross-sectional diagnostic design. All consecutive patients underwent modified TOE followed by EUS (reference standard) to assess the severity of distal AA atherosclerosis. We constructed contingency tables to compare the presence (and severity) of atherosclerosis, detected by the two techniques. RESULTS: The positive predictive value of modified TOE for the detection of clinically significant atherosclerosis was 67%, and the negative predictive value was 97%. The sensitivity was 95% and the specificity was 79%. One patient suffered a pulmonary haemorrhage, although he recovered without further sequelae. We did not observe any clinical significant haemodynamic or ventilatory effects. CONCLUSIONS: The high negative predictive value and sensitivity show that modified TOE yields adequate diagnostic accuracy for excluding clinically relevant aorta atherosclerosis without significant cardiopulmonary side-effects, provided that the A-View catheter is introduced carefully.

Economic aspects of deep sternal wound infections.

OBJECTIVES: Surgical-site infections are a very expensive complication in cardiac surgery. Thus, the total costs for coronary artery bypass grafting (CABG) surgery may substantially increase when a deep sternal wound infection (DSWI) occurs. This may be due to an extended length of stay (LOS), the need for additional surgical procedures, vacuum-assisted wound dressing and antibiotic therapy. This study compares the LOS in the hospital and on an intensive care unit (ICU) as well as the total costs for patients undergoing CABG depending upon the occurrence of a subsequent DSWI. METHODS: A case-control study was performed. Total costs of DSWI cases were analysed and compared to patients undergoing CABG without DSWI. Inclusion criterion for cases was the development of a DSWI according to the CDC criteria during hospital stay after CABG. Two control patients without any signs or symptoms of an infection during hospital stay were matched to each case by (1) type of surgery according to their diagnosis-related group (DRG), (2) age +/-5 years, (3) gender and (4) duration of preoperative hospital stay +/-2 days, but at least as long as the time at risk of cases before infection. RESULTS: Between January 2006 and March 2008, 17 CABG patients with DSWI (cases) and 34 matched controls were included. The median overall costs of a CABG case were 36,261 Euro compared with 13,356 Euro per control patient without infection (p<0.0001). The median overall LOS was 34.4 days versus 16.5 days, respectively (p=0.0006). The median LOS on ICU was 6.3 days versus 5.3 days (no significant difference). CONCLUSION: DSWI represents an important economic factor for the hospital as they may almost triple the costs for patients undergoing CABG. Thus, appropriate infection control measures for the prevention of DSWI should be enforced.

Preventing heart injury during negative pressure wound therapy in cardiac surgery: assessment using real-time magnetic resonance imaging.

OBJECTIVE: Heart rupture is a devastating complication to negative pressure wound therapy in cardiac surgery. Also, reduced cardiac output during negative pressure wound therapy has been reported. The present study aimed to examine the effects of negative pressure wound therapy on the position of the heart in relation to the thoracic wall using magnetic resonance imaging in a porcine sternotomy wound model. METHODS: Six pigs had median sternotomy followed by negative pressure wound therapy at -75, -125, and -175 mm Hg. Real-time magnetic resonance imaging movies (10 images/s) were acquired in a midventricular transverse plane or a midsagittal plane during the application of negative pressure wound therapy. RESULTS: Similar finding were observed at all different negative pressures studied. Negative pressure wound therapy caused the heart to be displaced toward the thoracic wall, and in some cases, the right ventricular free wall bulged into the space between the sternal edges, and the sharp edges of the sternum jutted into and deformed the anterior surface of the right ventricular free wall. These events were not affected by the interposition of 4 layers of paraffin gauze dressing but were hindered by the placement of a rigid barrier between the anterior portion of the heart and the inside of the thoracic wall. CONCLUSION: The results show altered position of the heart in relation to the sternum during negative pressure wound therapy. This may explain 2 potentially hazardous events associated with negative pressure wound therapy, namely, risk for heart rupture and reduced cardiac output. Inserting a rigid barrier over the heart may be a protective measure that is clinically practicable.

Radiographic assessment of sternal notch level and its significance in approaching the upper thoracic spine.

In this retrospective study, we used anteroposterior plain radiographs of the neck to analyze sternal notch level in relation to the upper thoracic spine and to assess the usefulness of this relation in deciding how to approach the upper thoracic spine. We reviewed 53 patients' anteroposterior plain radiographs of the cervicothoracic spine and thoracic magnetic resonance imaging (MRI) scans. On the plain radiographs, we drew a horizontal line joining the lower-fifth edge of the medial end of the 2 clavicles; on the midsagittal thoracic MRI scans, we drew a tangential line to the sternal notch. Then we noted the vertebral level of the 2 lines. In all cases, the horizontal line on the plain radiographs and the tangential line on the MRI scans corresponded to each other without discrepancy. We evaluated this method in a patient with a fractured T3 vertebral body, in whom a satisfactory procedure was performed using low anterior cervical spine approach. As the level of sternal notch is found to be present below the level of T2 and T3 radiologically in most cases, a low cervical approach can be contemplated in most patients with upper thoracic spine pathology depending on their sternal level as determined by preoperative radiographs. MRI scans are not needed to decide the approach, as it can be assessed with plain radiographs alone, as shown in this study.