F.Y. Bhora

Targeted detoxification of selected reactive oxygen species in the vascular endothelium.

Oxidative stress underlies diverse vascular diseases, but its management remains elusive, in part because of our inability to selectively detoxify reactive oxygen species (ROS) in pathological sites and our limited understanding which species need to be eliminated. The antioxidant enzymes (AOEs) superoxide dismutase (SOD) and catalase (which decompose and H2O2, respectively), conjugated with an antibody to platelet-endothelial cell adhesion molecule-1 (PECAM-1), bind to endothelial cells and alleviate oxidative stress in cell culture models. Here, we studied the effects of these antioxidant conjugates in mouse models of vascular oxidative stress. Anti-PECAM/catalase and anti-PECAM/SOD conjugates, in contrast to control IgG/AOE conjugates, accumulated in the lungs and vascularized organs after intravenous injection in wild-type, but not PECAM KO mice. Anti-PECAM/catalase, but not anti-PECAM/SOD, protected mice from lung injury induced by H2O2 produced by glucose oxidase deposited in the pulmonary vasculature. Anti-PECAM/catalase also reduced alveolar edema and attenuated decline in arterial oxygen in mice that underwent unilateral lung ischemia/reperfusion, whereas anti-PECAM/SOD was not effective, implying the key role of H2O2 in tissue damage in this pathology. In contrast, anti-PECAM/SOD, but not anti-PECAM/catalase prevented oxidation of tetrahydrobiopterin and normalized vasoreactivity in the vessels of mice rendered hypertensive by pretreatment with angiotensin-II. This outcome agrees with reports implicating superoxide and peroxynitrite in altered endothelium-dependent vasodilatation in hypertension. Therefore, the use of endothelial cell-targeted antioxidants identifies the key specific species of ROS involved in various forms of vascular disease and holds promise for the mechanistically tailored treatment of these pathologies.

Timely Airway Stenting Improves Survival in Patients With Malignant Central Airway Obstruction

BACKGROUNDnThe survival of patients with malignant central airway obstruction is very limited. Although airway stenting results in significant palliation of symptoms, data regarding improved survival after stenting for advanced thoracic cancer with central airway obstruction are lacking.nnnMETHODSnFifty patients received a total of 72 airway stents for malignant central airway obstruction over a two-year period at a single institution. The Medical Research Council (MRC) dyspnea scale and Eastern Cooperative Oncology Group (ECOG) performance status were used to divide patients into a poor performance group (MRC = 5, ECOG = 4) and an intermediate performance group (MRC ≤ 4, ECOG ≤ 3). The SPSS version 16.0 (SPSS Inc, Chicago, IL) and Microsoft Excel (Microsoft, Redmond, WA) were used to analyze the data. Survival curves were constructed using the Kaplan-Meier survival analysis method and a log-rank test was used to compare the survival distributions among different groups.nnnRESULTSnSuccessful patency of the airway was achieved in all patients with no procedure-related mortality. Stenting resulted in significant improvement in MRC and ECOG performance scores (p < 0.01). Significantly improved survival was observed only in patients in the intermediate performance group compared with patients in the poor performance group (p < 0.05).nnnCONCLUSIONSnAirway stenting resulted in significant palliation of symptoms in both groups as evaluated by MRC dyspnea scale and ECOG performance status. Compared with historic controls, a significant survival advantage was seen only in the intermediate performance group. We postulate that timely stenting of the airway, before the morbid complications of malignant central airway obstruction have set in, results in improved survival.

The ITMIG/IASLC thymic epithelial tumors staging project: A proposed lymph node map for thymic epithelial tumors in the forthcoming 8th edition of the TNM classification of malignant tumors

Although the presence of nodal disease is prognostic in thymic malignancy, the significance of the extent of nodal disease has yet to be defined. Lymph node dissection has not been routinely performed, and there is currently no node map defined for thymic malignancy. To establish a universal language for reporting as well as characterize the staging of this disease more accurately, an empiric node map is proposed here. This was developed using prior classification systems, series reporting specifics of nodal involvement, anatomical studies of lymphatic drainage, and preexisting node maps of the chest as defined by the International Association for the Study of Lung Cancer and the neck as defined by the American Academy of Otolaryngology—Head and Neck Surgery and the American Society for Head and Neck Surgery. The development of this node map was a joint effort by the International Thymic Malignancy Interest Group and the Thymic Domain of the IASLC Staging and Prognostic Factors Committee. It was reviewed and subsequently approved by the members of ITMIG. This map will be used as an adjunct to define node staging as part of a universal stage classification for thymic malignancy. As more data are gathered using definitions set forth by this node map, a revision may be undertaken in the future.

Surgical Residents' Perception of the 16-Hour Work Day Restriction: Concern for Negative Impact on Resident Education and Patient Care

BACKGROUNDnEffective July 1, 2011, the Accreditation Council for Graduate Medical Education (ACGME) instituted a 16-hour duty period limitation for postgraduate year I (PGY I) residents. Our aim was to assess the attitudes and perception of general surgery residents regarding the new duty hour limitation as well as the transfer of care process under the new guidelines.nnnSTUDY DESIGNnAn anonymous, web-based survey was conducted nationally 7 months after the institution of the 16-hour duty limitation.nnnRESULTSnA total of 464 completed surveys were analyzed. Overall, 75% of residents expressed dissatisfaction with the new duty hour limitation. PGY II to V residents reported a higher level of dissatisfaction compared with PGY I residents (87% vs 54%, p < 0.01). Eighty-nine percent of PGY II to V residents responded that there has been a shift of responsibilities from the PGY I class to PGY II to V residents, with 73% reporting increased fatigue as a result. Seventy-five percent of PGY I and 94% of PGY II to V residents expressed concerns about the adverse impact of the restrictions on the education of PGY I residents (p < 0.01). Residents at all PGY training levels reported encountering problems due to inadequate sign-outs (PGY I, 59%; PGY II to V, 85%; p < 0.01). Sixty-two percent of PGY I residents and 54% of PGY II to V residents believed that the new 16-hour duty restriction contributes to inadequate sign-outs (p = NS). Most PGY II to V residents (86%) believe there is a decreased level of patient ownership due to the work hour restrictions.nnnCONCLUSIONSnThe results of the survey suggest that the majority of general surgery residents are concerned over the potential negative impact of the duty limitation on resident education and patient care. Further research is needed to address these concerns.

A Modern Definition of Mediastinal Compartments

Division of the mediastinum into compartments is used to help narrow the differential diagnosis of newly detected mediastinal masses, to assist in planning biopsy and surgical procedures, and to facilitate communication among clinicians of multiple disciplines. Several traditional mediastinal division schemes exist based upon arbitrary landmarks on the lateral chest radiograph. We describe a modern, computed tomography-based mediastinal division scheme, which has been accepted by the International Thymic Malignancy Interest Group as a new standard. This clinical classification defines a prevascular (anterior), a visceral (middle), and a paravertebral (posterior) compartment, with anatomic boundaries defined clearly by computed tomography. It is our intention that this definition be used in the reporting of clinical cases and the design of prospective clinical trials.

Robotic intercostal nerve graft for reversal of thoracic sympathectomy: a large animal feasibility model

A subset of patients who undergo video‐assisted thoracoscopic sympathectomy for hyperhydrosis develop post‐procedure compensatory sweating that is perceived as more debilitating than their initial complaints. We propose a novel treatment to reverse sympathectomy by implantation of an intercostal nerve graft using the da Vinci robot.

Dietary Flaxseed Protects Against Lung Ischemia Reperfusion Injury Via Inhibition of Apoptosis and Inflammation in a Murine Model

BACKGROUNDnThe hallmark of lung ischemia-reperfusion injury (IRI) is the production of reactive oxygen species (ROS), and the resultant oxidant stress has been implicated in apoptotic cell death as well as subsequent development of inflammation. Dietary flaxseed (FS) is a rich source of naturally occurring antioxidants and has been shown to reduce lung IRI in mice. However, the mechanisms underlying the protective effects of FS in IRI remain to be determined.nnnMETHODSnWe used a mouse model of IRI with 60 min of ischemia followed by 180 min of reperfusion and evaluated the anti-apoptotic and anti-inflammatory effects of 10% FS dietary supplementation.nnnRESULTSnMice fed 10% FS undergoing lung IRI had significantly lower levels of caspases and decreased apoptotic activity compared with mice fed 0% FS. Lung homogenates and bronchoalveolar lavage fluid analysis demonstrated significantly reduced inflammatory infiltrate in mice fed with 10% FS diet. Additionally, 10% FS treated mice showed significantly increased expression of antioxidant enzymes and decreased markers of lung injury.nnnCONCLUSIONSnWe conclude that dietary FS is protective against lung IRI in a clinically relevant murine model, and this protective effect may in part be mediated by the inhibition of apoptosis and inflammation.

Robotic Brachytherapy and Sublobar Resection for T1 Non-Small Cell Lung Cancer in High-Risk Patients

BACKGROUNDnSublobar lung resection and brachytherapy seed placement is gaining acceptance for T1 non-small cell lung cancer (NSCLC) in select patients with comorbidities precluding lobectomy. Our institution first reported utilization of the da Vinci system for robotic brachytherapy developed experimentally in swine and applied to high-risk patients 5 years ago. We now report seed dosimetrics and midterm follow-up.nnnMETHODSnEleven high-risk patients with stage IA NSCLC who were not candidates for conventional lobectomy underwent limited resection of 12 primary tumors. To reduce locoregional recurrence, (125)I brachytherapy seeds were robotically sutured intracorporeally over resection margins to deliver 14,400 cGy 1 cm from the implant plane. Patients were followed with dosimetric computed tomography scans at 30 +/- 16 days. Survival and sites of recurrence were documented.nnnRESULTSnResected tumor size averaged 1.48 +/- 0.38 cm (range, 1.1 to 2.1 cm). Perioperative mortality was 0% and recurrence was 9% (1 of 11 [margin recurrence at 6 months with resultant mortality at 1 year]). Follow-up duration was 31.82 +/- 17.35 months. Dosimetrics confirmed 14,400 cGy delivery using 24.21 +/- 4.6 (125)I seeds (range, 17 to 30 seeds) over a planning target volume of 10.29 +/- 2.39 cc(3). Overall, 84.1% of the planning target volume was covered by 100% of the prescription dose (V100), and 88.2% was covered by 87% of the prescription dose (V87), comparable to open dosimetric data at our institution. Follow-up imaging confirmed seed stability in all patients.nnnCONCLUSIONSnRobotic (125)I brachytherapy seed placement is a feasible adjuvant procedure to reduce the incidence of recurrence after sublobar resection in medically compromised patients. Tailored robotic seed placement delivers an exact dosing regimen in a minimally invasive fashion with equivalent precision to open surgery.

Uncommon etiology of an anterior chest wall mass.

A rare but important constellation of musculoskeletal and cutaneous symptoms, including synovitis, acne, pustulosis, hyperostosis, and osteitis, has recently been designated the SAPHO syndrome. The exact etiology is unknown, although various infectious agents have been proposed. The most common site of osteoarticular involvement is the sternoclavicular joint, and therefore, recognition of this syndrome and appropriate workup and management is crucial in the differential diagnosis of an anterior chest wall mass.

What technical barriers exist for real-time fluoroscopic and video image overlay in robotic surgery?†

A hypothetical advantage of the da Vinci® console is its ability to integrate multiple visual data sources. Current platforms for augmented reality surgery fuse pre‐operative radiographic studies but are limited with their ability to update with intra‐operative imaging. The aim of our study was to evaluate the feasibility of real‐time radiographic image overlay with current technology.