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Concept: Sternum

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OBJECTIVE: Anterior chest thrusts (with the subject sitting or standing and thrusts applied to the lower sternum) are recommended by the Australian Resuscitation Council as part of the sequence for clearing upper airway obstruction by a foreign body. Lateral chest thrusts (with the victim lying on their side) are no longer recommended due to a lack of evidence. We compared anterior, lateral chest and abdominal thrusts in the generation of airway pressures using a suitable animal model. METHODS: This was a repeated-measures, cross-over, clinical trial of eight anaesthetised, intubated, adult pigs. For each animal, ten trials of each technique were undertaken with the upper airway obstructed. A chest/abdominal pressure transducer, a pneumotachograph and an intra-oesophageal balloon catheter recorded chest/abdominal thrust, expiratory air flows, airway and intrapleural pressures, respectively. RESULTS: The mean (SD) thrust pressures generated for the anterior, lateral and abdominal techniques were 120.9 (11.0), 135.2 (20.0), and 142.4 (27.3) cmH(2)O, respectively (p<0.0001). The mean (SD) peak expiratory airway pressures were 6.5 (3.0), 18.0 (5.5) and 13.8 (6.7) cmH(2)O, respectively (p<0.0001). The mean (SD) peak expiratory intrapleural pressures were 5.4 (2.7), 13.5 (6.2) and 10.3 (8.5) cmH(2)O, respectively (p<0.0001). At autopsy, no rib, intra-abdominal or intra-thoracic injury was observed. CONCLUSION: Lateral chest and abdominal thrust techniques generated significantly greater airway and pleural pressures than the anterior thrust technique. We recommend further research to provide additional evidence that may inform management guidelines for clearing foreign body upper airway obstruction.

Concepts: Sternum, Pressure, Thorax, Obstructive lung disease, Pleural cavity, Victim, Thrust, Pressure sensor

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BACKGROUND: This study investigated the incidence, imaging characteristics and mechanical factors in scoliotic patients with pectus excavatum. METHODS: A total of 142 scoliostic patients with pectus excavatum were evaluated prior to operation. The evaluation included a complete physical exam, phenotype and severity of the pectus excavatum, incidence and severity of scoliosis, and analysis of radiological images, including calculation of the Haller index. RESULTS: Twenty five out of 142 patients (17.61%) with pectus excavatum had scoliosis with a Cobb angle >10 degrees, and in 80.00% of the cases the spinal column was bent to the right. Seventeen patients had bent-to-the-right spines that involved the 6th to 10 th thoracic vertebrae. We found that 23 out of 25 patients with a Cobb angle more than 10 [degree sign] were teenagers and adults. The incidence of scoliosis was only 6.06% in the children under 11 years whereas it was 21.79% in the teenage group. CONCLUSIONS: Mechanical forces appear to play a role in the coexistence of pectus excavatum and scoliosis. There is a relationship between age, severity (Haller index), asymmetry and scoliosis. The heart and mediastinum play a role in providing an outward force to the left of the sternum which may be an important reason for the coexistence of pectus excavatum and scoliosis, but the correlation needs further proof.

Concepts: Vertebral column, Pectus excavatum, Haller index, Chest, Degree, Sternum, Scoliosis

167

OBJECTIVESSternal wound complications following median sternotomy remain a challenge in cardiac surgery. Changes in both patient profile and type of operations have been observed in recent years. Therefore, we analysed current wound healing complications after median sternotomy at our centre.METHODSAll adult patients undergoing a median sternotomy between January 2009 and April 2011 were included in this retrospective analysis. Transplants and assist devices implantations were omitted. We assessed outcome, prognostic factors and microbiological results of standardized wound swabs.RESULTSIn total, 1297 patients with an average age of 67.0 ± 12.7 years were analysed. Operation types included 598 solitary coronary artery bypass grafts (CABGs), 213 solitary valve procedures, 105 CABGs with aortic valve replacement and 116 solitary aortic operations or conduit implantations. Furthermore, 255 of the remaining 265 were combined or otherwise complex procedures. Superficial healing disorders occurred in 43 patients (3.3%), while 33 (2.5%) developed deep wound complications. Six patients with sternal wound complications (7.9%) died in-hospital. In 7 patients, no pathogen was identified and the wound appeared uninfected (21% of all deep complications or 0.05% of all patients). These healing disorders were considered deep dehiscences. Patients with insulin-dependent diabetes mellitus, BMI of >40 kg/m(2) and who underwent reoperation were prone to superficial infections. Risk factors for all deep sternal wound complications were insulin-dependent diabetes mellitus, COPD and reoperation. Moreover, multivariate analysis revealed ‘emergency’ as an independent prognostic factor for all sternal wound complications. Microbial swabs of the sternal wound were taken in 82 of the 1297 patients (6.6%). Pathogens of the normal skin flora represented the majority of pathogens in both superficial and deep wound complications. Eight patients with deep, but only 2 patients with superficial complications suffered from polymicrobial infections. All deep polymicrobial infections involved coagulase-negative Staphylococci.CONCLUSIONSWound complications following median sternotomy remain a challenge to cardiac surgery. Redo and emergency operations are the most important risk factors in this contemporary series. More efforts seem mandatory to decrease this arduous morbidity and the costs of prolonged treatment.

Concepts: Myocardial infarction, Insulin, Diabetes mellitus, Heart, Sternum, Wound, Coronary artery bypass surgery, Median sternotomy

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INTRODUCTION: Blunt cardiac rupture is an exceedingly rare injury. CASE PRESENTATION: We report a case of blunt cardiac trauma in a 43-year-old Caucasian German mother with pectus excavatum who presented after a car accident in which she had been sitting in the front seat holding her two-year-old boy in her arms. The mother was awake and alert during the initial two hours after the accident but then proceeded to hemodynamically collapse. The child did not sustain any severe injuries. Intraoperatively, a combined one-cm laceration of the left atrium and right ventricle was found. CONCLUSION: Patients with pectus excavatum have an increased risk for cardiac rupture after blunt chest trauma because of compression between the sternum and spine. Therefore, patients with pectus excavatum and blunt chest trauma should be admitted to a Level I Trauma Center with a high degree of suspicion.

Concepts: Heart, Pectus excavatum, Chest, Sternum, Ventricle, Left ventricle, Physical trauma, Chest trauma

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The Nuss procedure, which is a minimally invasive approach for treating pectus excavatum, has better functional and cosmetic outcomes than other invasive procedures. Cardiac perforation is the most serious complication and several methods for the prevention of intraoperative events has been developed. Although most cardiac injuries are detected in the operating room, in the case described herein the patient experienced sudden hypovolemic shock during the postoperative recovery period. This indicates that special caution is mandatory even after successful execution of the Nuss procedure.

Concepts: Blood, Surgery, Pectus excavatum, Chest, Sternum, Shock, Minimally invasive, Hypovolemia

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The goal of this study was to investigate alternative strategies to the sternal resection in the treatment of post-sternotomy osteomyelitis. We report our experience in the treatment of chronic infection of median sternotomy following open heart surgery without sternal resection.

Concepts: Sternum, Cardiothoracic surgery, Cardiac surgery

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BACKGROUND: Sternal dehiscence is a grave complication after open heart surgery. Sternal debridement and flap coverage are the mainstays of therapy, but no consensus exists regarding the appropriate level of debridement. More recently, the use of vacuum-assisted closure devices has been advocated as a bridge to definitive closure, but indications for use remain incompletely defined. MATERIALS AND METHODS: A retrospective review of all chest wall reconstructions performed from January 2000 to December 2010 was conducted. The type of operative management was evaluated to assess morbidity, mortality, and length of hospital stay. RESULTS: Fifty-four patients underwent chest wall reconstruction for poststernotomy mediastinitis. Of these patients, 24 underwent conservative sternal debridement with flap closure, 24 underwent radical sternectomy including resection of the costal cartilages followed by flap closure, and 6 underwent radical sternectomy with vacuum-assisted closure therapy followed by flap closure in a delayed fashion. There were 15 patients in the conservative group and 8 patients in the radical sternectomy group who developed postoperative complications (62.5% vs 33.3%, P < 0.05). The conservative sternectomy group had more serious complications requiring reoperation compared to the radical sternectomy group (86.7% vs 25.0%, P < 0.05). The most common complication in the former group was flap dehiscence (8/15, 53.3%), whereas that in the latter group was a superficial wound infection (6/8, 75.0%). There was no significant difference in mortality (25.0% vs 25.0%, P > 0.05%) or length of hospital stay. CONCLUSIONS: Radical sternectomy including the costal cartilages is associated with lower rates of surgical morbidity and reoperation, but not mortality.

Concepts: Heart, Surgery, Sternum, Wound, Cardiothoracic surgery, Cardiac surgery

28

This study documents the prevalence of cut mark characteristics in fresh and burned domestic pig ribs. Stab wounds from single edge serrated and smooth-edged knives were inflicted in the vertebral and sternal regions of each fresh rib. Each rack of ribs was then divided into vertebral and sternal units. Vertebral units were defleshed and their associated cut marks were examined using a stereomicroscope. Sternal units were burned in an outdoor fire pit and examined with the addition of a scanning electron microscope (SEM). Linear cuts, V-shaped cross-sections, mounding, hinge fractures, and wastage were all observed on burned ribs. There was an overall decrease in the prevalence of all features (up to a 40% decrease), regardless of knife type, in burned ribs. Striations within cut marks were not observed in either fresh or burned ribs. Oblique faulting and bone lifts could only be observed using the SEM. Mounding and wastage were obliterated during the burning process. Therefore, cut marks in burned bone should ideally be examined for their characteristics utilizing an SEM.

Concepts: Electron, Electron microscope, Bone, Sternum, Scanning electron microscope, Rib

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Several techniques exist for the repair of complex pectus excavatum. The placement of retrosternal metal bars improves the results by reducing the recurrence rate, but entails several possible risks, complications and disadvantages. A new method, specifically conceived for the repair of severe, asymmetric forms in adult patients, is reported. The corrected bone is fixed in the proper position by two, patient-customized, titanium struts, externally screwed to the manubrium and sternal body. Any retrosternal bar is thus avoided, reducing possible complications, without hampering the chest wall dynamic. In this particularly difficult issue, this technique provides long-term good functional, mechanical and cosmetic results and does not entail a second surgery for struts removal.

Concepts: Heart, Pectus excavatum, Chest, Sternum, Pectus carinatum, Adult, Moral hazard, Fee tail

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Background Postoperative acute pain can cause anxiety and decrease the quality of life in patients. Acute sternal bone pain after cardiac surgery can persist for long time.Objective The aim of this study is to explore the relationships between the degree of sternal misalignment and the degree of acute sternal pain after coronary artery bypass grafting surgery (CABG).Methods We retrospectively reviewed postoperative coronary computed tomographic (CT) angiography and medical records in 104 patients who received CABG between May 1, 2009 and January 31, 2011. CT scan was classified into five categories, and we compared the degree of misalignment and subjective pain via numerical rating scale (NRS) system.Results Positive correlation was noted between NRS and the degree of sternal misalignment (Pearson correlation coefficient 0.660, p = 0.000).Conclusion Postoperative sternal pain is related to the degree of misalignment of the sternal halves. It would be appropriate for surgeons to approximate the sternal halves accurately to decrease the postoperative sternal wound pain in the first place.

Concepts: Atherosclerosis, Heart, Spearman's rank correlation coefficient, Sternum, Correlation and dependence, Coronary artery bypass surgery, Pearson product-moment correlation coefficient, Median sternotomy