Risk Factors for Stroke Development After Thoracic Aortic Surgery.

OBJECTIVES: Stroke after thoracic aortic surgery is a complication that is associated with poor outcomes. The aim is to characterize the intraoperative risk factors for stroke development. DESIGN: A retrospective analysis. SETTING: Tertiary, high-volume cardiac surgery center. PARTICIPANTS: Patients who had surgical repair of thoracic aortic diseases from January 1, 2017, through December 31, 2021. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 704 patients were included, of whom 533 had ascending aortic aneurysms, and 171 had type A aortic dissection. The incidence of postoperative stroke was 4.5% (95% CI 2.9%-6.6%) for ascending aortic aneurysms compared with 12.3% (95% CI 7.8%-18.16%) in type-A aortic dissections. Patients who developed postoperative strokes had significantly lower intraoperative hemoglobin median (7.5 gm/dL [IQR 6.8-8.6] v 8.55 gm/dL [IQR 7.3-10.0]; p < 0.001). The median cardiopulmonary bypass time was 185 minutes (IQR 136-328) in the stroke group versus 156 minutes (IQR 113-206) in the nonstroke group (p = 0.014). Circulatory arrest was used in 57.8% versus 38.5% of the nonstroke patients (p = 0.017). The initial temperature after leaving the operating room was lower, with a median of 35.0°C (IQR 34-35.92) in the stroke group versus 35.5°C (IQR 35-36) in the nonstroke cohort (p = 0.021). CONCLUSIONS: This single-center study highlighted the potential importance of intra-operative factors in preventing stroke. Lower hemoglobin, longer duration of cardiopulmonary bypass, deep hypothermic circulatory arrest, and postoperative hypothermia are potential risk factors for postoperative stroke. Further studies are needed to prevent this significant complication in patients with thoracic aortic diseases.

The financial burden associated with endovascular repair of thoracoabdominal and pararenal aortic aneurysms using physician-modified fenestrated-branched endografts.

OBJECTIVE/BACKGROUND: Endovascular thoracoabdominal and pararenal aortic aneurysm repair is more complex and requires more devices than infrarenal aneurysm repair. It is unclear if current reimbursement covers the cost of delivering this more advanced form of vascular care. The objective of this study was to evaluate the economics of fenestrated-branched (FB-EVAR) physician-modified endograft (PMEG) repairs. METHODS: We obtained technical and professional cost and revenue data for four consecutive fiscal years (July 1, 2017, to June 30, 2021) at our quaternary referral institution. Inclusion criteria were patients who underwent PMEG FB-EVAR in a uniform fashion by a single surgeon for thoracoabdominal/pararenal aortic aneurysms. Patients in industry-sponsored clinical trials or receiving Cook Zenith Fenestrated grafts were excluded. Financial data were analyzed for the index operation. Technical costs were divided into direct costs that included devices and billable supplies and indirect costs including overhead. RESULTS: 62 patients (79% male, mean age: 74 years, 66% thoracoabdominal aneurysms) met inclusion criteria. The mean aneurysm size was 6.0 cm, the mean total operating time was 219 minutes, and the median hospital length of stay was 2 days. PMEGs were created with a mean number of 3.7 fenestrations, using a mean of 8.6 implantable devices per case. The average technical cost per case was $71,198, and the average technical reimbursement was $57,642, providing a net negative technical margin of $13,556 per case. Of this cohort, 31 patients (50%) were insured by Medicare remunerated under diagnosis-related group code 268/269. Their respective average technical reimbursement was $41,293, with a mean negative margin of $22,989 per case, with similar findings for professional costs. The primary driver of technical cost was implantable devices, accounting for 77% of total technical cost per case over the study period. The total operating margin, including technical and professional cost and revenue, for the cohort during the study period was negative $1,560,422. CONCLUSIONS: PMEG FB-EVAR for pararenal/thoracoabdominal aortic aneurysms produces a substantially negative operating margin for the index operation driven largely by device costs. Device cost alone already exceeds total technical revenue and presents an opportunity for cost reduction. In addition, increased reimbursement for FB-EVAR, especially among Medicare beneficiaries, will be important to facilitate patient access to such innovative technology.

Recovery of critical metals from spent Li-ion batteries: Sequential leaching, precipitation, and cobalt-nickel separation using Cyphos IL104.

This study presents a novel recycling scheme for spent Li-ion batteries that involves the leaching of lithium in hot water followed by the dissolution of all transition metals in HCl solution and their separation using the ionic liquid Cyphos IL104. The parametric studies revealed that >84 % Li was dissolved while the cathode material was leached at 90 °C for 2 h. Approximately 98 % Li from the non-acidic solution was directly precipitated as Li2CO3 at a Li+:CO32- ratio of 1:1.5. The transition metals from the Li-depleted cathode mass were efficiently (>98 %) dissolved in 3.0 mol·L-1 HCl at 90 °C for a 3 h leaching process. Manganese from the chloride leach liquor was selectively precipitated by adding KMnO4 at a 1.25-fold higher quantity than the stoichiometric ratio, pH value 2.0, and temperature 80 °C. The remaining co-existing metals (Ni and Co) were separated from the chloride solution by contacting it with a phosphonium-based ionic liquid at an equilibrium pH value of 5.4 and an organic-to-aqueous phase ratio of 2/3. The loaded ionic liquid was quantitatively stripped in 2.0 mol·L-1 H2SO4 solution, which yielded high-purity CoSO4·xH2O crystals after evaporation of the stripped liquor. Subsequently, ∼99 % nickel was recovered as nickel carbonate [NiCO3·2Ni(OH)2] from the Co-depleted raffinate by the precipitation performed at Ni2+:CO32- ratio of 1:2.5, pH value of 10.8, and temperature of 50 °C. Finally, a process flow with mass and energy balances yielding a high recovery rate of all metals in the exhausted cathode powder of spent LiBs was proposed.

Management of the no-option foot: Deep vein arterialization.

The incidence of peripheral artery disease continues to rise worldwide, with a concomitant rise in the subset of patients who manifest with chronic limb-threatening ischemia (CLTI). A mainstay of CLTI treatment is revascularization through open surgical bypass, endovascular therapy, or hybrid approaches combining the two modalities. However, a significant proportion of these patients are considered to have nonreconstructable, or no-option, CLTI. This is related to either significant pedal arterial occlusive disease or lack of a bypass conduit. Deep vein arterialization has been used as a potential treatment option for this cohort of patients. We explore the various described methodologies of deep vein arterialization, including open, hybrid, and totally percutaneous. These studies suggest that deep vein arterialization is a promising treatment paradigm for patients with no-option CLTI, with encouraging results in terms of technical feasibility, wound healing, and ultimately limb salvage. However, further study of appropriate patient selection, standardization of techniques, and long-term follow-up are needed.

Non-guideline-compliant endovascular abdominal aortic aneurysm repair in women is associated with increased mortality and reintervention compared with men.

OBJECTIVE: Sex-based disparities in surgical outcomes have emerged as an important focus in contemporary healthcare delivery. Likewise, the appropriate usage of endovascular abdominal aortic aneurysm repair (EVAR) in the United States remains a subject of ongoing controversy, with a significant number of U.S. EVARs failing to adhere to the Society for Vascular Surgery (SVS) clinical practice guideline (CPG) diameter thresholds. The purpose of the present study was to determine the effect of sex among patients undergoing EVAR that was not compliant with the SVS CPGs. METHODS: All elective EVAR procedures for abdominal aortic aneurysms without a concomitant iliac aneurysm (≥3.0 cm) in the SVS Vascular Quality Initiative were analyzed (2015-2019; n = 25,112). SVS CPG noncompliant repairs were defined as a size of <5.5 cm for men and <5.0 cm for women. The primary endpoint was 30-day mortality. The secondary endpoints were all-cause mortality, complications, and reintervention. Logistic regression was performed to control for surgeon- and patient-level factors. Freedom from the endpoints was determined using the Kaplan-Meier method. RESULTS: Noncompliant EVAR was performed in 9675 patients (38.5%). Although men were significantly more likely to undergo such procedures (90% vs 10%; odds ratio [OR], 3.1; 95% confidence interval [CI], 2.9-3.4; P < .0001), the 30-day mortality was greater for the women than the men (1.8% vs 0.5%; P = .0003). Women also experienced significantly higher rates of multiple complications, including postoperative myocardial infarction (1% vs 0.3%; P = .006), respiratory failure (1.4% vs 0.6%; P = .01), intestinal ischemia (0.7% vs 0.2%; P = .003), access vessel hematoma (3% vs 1.2%; P = .0006), and iliac access vessel injury (2.4% vs 0.8%; P < .0001). Additionally, women experienced increased overall 1-year reintervention rates (11.5% vs 5.8%; P < .0001). In the adjusted analysis, 30-day mortality and any in-hospital complication risk remained significantly greater for the women (30-day death: OR, 3.1; 95% CI, 1.6-5.8; P = .0005; in-hospital complication: OR, 1.9; 95% CI, 1.4-2.6; P < .0001). Women also experienced increased reintervention rates over time compared with men (OR, 1.5; 95% CI, 1.1-2.2; P = .02). CONCLUSIONS: Although men were more likely to undergo non-CPG compliant EVAR, women experienced increased short-term morbidity and 30-day mortality and higher rates of reintervention when undergoing non-CPG compliant EVAR. These unanticipated findings necessitate increased scrutiny of current U.S. sex-based EVAR practice and should caution against the use of non-CPG compliant EVAR for women.

Recognition of human gastrointestinal cancer neoantigens by circulating PD-1+ lymphocytes.

Tumor-resident lymphocytes can mount a response against neoantigens expressed in microsatellite-stable gastrointestinal (GI) cancers, and adoptive transfer of neoantigen-specific lymphocytes has demonstrated antitumor activity in selected patients. However, whether peripheral blood could be used as an alternative minimally invasive source to identify lymphocytes targeting neoantigens in patients with GI cancer with relatively low mutation burden is unclear. We used a personalized high-throughput screening strategy to investigate whether PD-1 expression in peripheral blood could be used to identify CD8+ or CD4+ lymphocytes recognizing neoantigens identified by whole-exome sequencing in 7 patients with GI cancer. We found that neoantigen-specific lymphocytes were preferentially enriched in the CD8+PD-1+/hi or CD4+PD-1+/hi subsets, but not in the corresponding bulk or PD-1- fractions. In 6 of 7 individuals analyzed we identified circulating CD8+ and CD4+ lymphocytes targeting 6 and 4 neoantigens, respectively. Moreover, neoantigen-reactive T cells and a T cell receptor (TCR) isolated from the CD8+PD-1+ subsets recognized autologous tumor, albeit at reduced levels, in 2 patients with available cell lines. These data demonstrate the existence of circulating T cells targeting neoantigens in GI cancer patients and provide an approach to generate enriched populations of personalized neoantigen-specific lymphocytes and isolate TCRs that could be exploited therapeutically to treat cancer.

Survey of Surgical Oncology Fellowship Graduates 2005-2016: Insight into Initial Practice.

BACKGROUND: Despite burgeoning interest in Complex General Surgical Oncology (CGSO) fellowship training, little is reported about postgraduate employment. The goal of this study was to characterize CGSO graduates' first employment and to identify factors that influenced this decision. METHODS: The National Cancer Institute (NCI) and Society of Surgical Oncology developed and distributed an electronic survey to CGSO fellows who graduated from 2005 to 2016. RESULTS: The survey response rate was 47% (237/509). Fifty-seven percent of respondents were first employed as faculty surgeons at a university-based/affiliated hospital, with 15% returning to their residency institution. The distribution of respondents' current employment across the United States mirrored the locations of their hometowns. Eighty-five percent of respondents care for patients across at least three disease types, most commonly hepatopancreatobiliary (81%), esophagus/gastric (75%), and sarcoma (74%). Twenty-seven percent of respondents spend the majority of their time in one area of surgical oncology; melanoma, breast, and head/neck were the most common. Two-thirds of respondents (67%) reported that they performed either clinical or basic science research as part of their current position. Multiple factors influenced the decision of first faculty position. CONCLUSIONS: Most CGSO graduates are employed at academic medical centers across the country in proximity to NCI-designated centers, treat a variety of disease types, and spend a percentage of their time dedicated to clinical research.

Randomized, Prospective Evaluation Comparing Intensity of Lymphodepletion Before Adoptive Transfer of Tumor-Infiltrating Lymphocytes for Patients With Metastatic Melanoma.

PURPOSE: Adoptive cell transfer, the infusion of large numbers of activated autologous lymphocytes, can mediate objective tumor regression in a majority of patients with metastatic melanoma (52 of 93; 56%). Addition and intensification of total body irradiation (TBI) to the preparative lymphodepleting chemotherapy regimen in sequential trials improved objective partial and complete response (CR) rates. Here, we evaluated the importance of adding TBI to the adoptive transfer of tumor-infiltrating lymphocytes (TIL) in a randomized fashion. PATIENTS AND METHODS: A total of 101 patients with metastatic melanoma, including 76 patients with M1c disease, were randomly assigned to receive nonmyeloablative chemotherapy with or without 1,200 cGy TBI before transfer of tumor-infiltrating lymphcytes. Primary end points were CR rate (as defined by Response Evaluation Criteria in Solid Tumors v1.0) and overall survival (OS). Clinical and laboratory data were analyzed for correlates of response. RESULTS: CR rates were 24% in both groups (12 of 50 v 12 of 51), and OS was also similar (median OS, 38.2 v 36.6 months; hazard ratio, 1.11; 95% CI, 0.65 to 1.91; P = .71). Thrombotic microangiopathy was an adverse event unique to the TBI arm and occurred in 13 of 48 treated patients. With a median potential follow-up of 40.9 months, only one of 24 patients who achieved a CR recurred. CONCLUSION: Adoptive cell transfer can mediate durable complete regressions in 24% of patients with metastatic melanoma, with median survival > 3 years. Results were similar using chemotherapy preparative regimens with or without addition of TBI.

Prospective identification of neoantigen-specific lymphocytes in the peripheral blood of melanoma patients.

Detection of lymphocytes that target tumor-specific mutant neoantigens--derived from products encoded by mutated genes in the tumor--is mostly limited to tumor-resident lymphocytes, but whether these lymphocytes often occur in the circulation is unclear. We recently reported that intratumoral expression of the programmed cell death 1 (PD-1) receptor can guide the identification of the patient-specific repertoire of tumor-reactive CD8(+) lymphocytes that reside in the tumor. In view of these findings, we investigated whether PD-1 expression on peripheral blood lymphocytes could be used as a biomarker to detect T cells that target neoantigens. By using a high-throughput personalized screening approach, we identified neoantigen-specific lymphocytes in the peripheral blood of three of four melanoma patients. Despite their low frequency in the circulation, we found that CD8(+)PD-1(+), but not CD8(+)PD-1(-), cell populations had lymphocytes that targeted 3, 3 and 1 unique, patient-specific neoantigens, respectively. We show that neoantigen-specific T cells and gene-engineered lymphocytes expressing neoantigen-specific T cell receptors (TCRs) isolated from peripheral blood recognized autologous tumors. Notably, the tumor-antigen specificities and TCR repertoires of the circulating and tumor-infiltrating CD8(+)PD-1(+) cells appeared similar, implying that the circulating CD8(+)PD-1(+) lymphocytes could provide a window into the tumor-resident antitumor lymphocytes. Thus, expression of PD-1 identifies a diverse and patient-specific antitumor T cell response in peripheral blood, providing a novel noninvasive strategy to develop personalized therapies using neoantigen-reactive lymphocytes or TCRs to treat cancer.

Landscape of Tumor Antigens in T Cell Immunotherapy.

Cancer immunotherapy is a rapidly evolving field that exploits T cell responses to tumor-associated Ags to induce tumor rejection. Molecular identification of tumor rejection Ags has helped define several classes of Ags, including tissue differentiation and tumor germline Ags. The ability to genetically engineer Ag-specific receptors into T cells provides an opportunity to translate these findings into therapies. New immunotherapy agents, notably checkpoint inhibitors, have demonstrated unprecedented efficacy in certain cancers. However, the nature of the Ags driving those beneficial immune responses remains unclear. New evidence suggests that tumors express immunogenic, tumor-specific epitopes generated from the same mutations that drive cancer development. Correlations between cancer types responding to immunotherapies and the frequency of somatic mutations may clarify what drives natural antitumor immune responses. This fusion of tumor immunology and genetics is leading to new ways to target this class of ideal tumor-specific Ags and could allow the application of immunotherapy to many cancers.

Successful placement of intracranial pressure monitors by trauma surgeons.

BACKGROUND: The Brain Trauma Foundation guidelines advocate for the use of intracranial pressure (ICP) monitoring following traumatic brain injury (TBI) in patients with a Glasgow Coma Scale (GCS) score of 8 or less and an abnormal computed tomographic scan finding. The absence of 24-hour in-house neurosurgery coverage can negatively impact timely monitor placement. We reviewed the safety profile of ICP monitor placement by trauma surgeons trained and credentialed in their insertion by neurosurgeons. METHODS: In 2005, the in-house trauma surgeons at a Level I trauma center were trained and credentialed in the placement of ICP parenchymal monitors by the neurosurgeons. We abstracted all TBI patients who had ICP monitors placed during a 6-year period. Demographic information, Injury Severity Score (ISS), outcome, and monitor placement by neurosurgery or trauma surgery were identified. Misplacement, hemorrhage, infections, malfunctions, and dislodgement were considered complications. Comparisons were performed by χ testing and Student's t tests. RESULTS: During the 6-year period, 410 ICP monitors were placed for TBI. The mean (SD) patient age was 40.9 (18.9) years, 73.7% were male, mean (SD) ISS was 28.3 (9.4), mean (SD) length of stay was 19 (16) days, and mortality was 36.1%. Motor vehicle collisions and falls were the most common mechanisms of injury (35.2% and 28.7%, respectively). The trauma surgeons placed 71.7 % of the ICP monitors and neurosurgeons for the remainder. The neurosurgeons placed most of their ICP monitors (71.8%) in the operating room during craniotomy. The overall complication rate was 2.4%. There was no significant difference in complications between the trauma surgeons and neurosurgeons (3% vs. 0.8%, p = 0.2951). CONCLUSION: After appropriate training, ICP monitors can be safely placed by trauma surgeons with minimal adverse effects. With current and expected specialty shortages, acute care surgeons can successfully adopt procedures such as ICP monitor placement with minimal complications. LEVEL OF EVIDENCE: Therapeutic/care management study, level IV.

Complications arising from splenic artery embolization: a review of an 11-year experience.

BACKGROUND: Splenic artery embolization (SAE) is a staple adjunct in the management of blunt splenic trauma. We examined complications of SAE over an 11-year period. METHODS: Patients who underwent SAE were identified. Demographic data and the location of the SAE-proximal, distal, or combined-were noted. Major and minor complications were identified. RESULTS: Of 1,383 patients with blunt splenic trauma, 298 (21.5%) underwent operative management, and 1,085 (78.5%) underwent nonoperative management (NOM). SAE was performed in 8.1% of the NOM group. Major complications which occurred in 14% of patients, included splenic abscesses, infarction, cysts, and contrast-induced renal insufficiency. Three-fourths of patients with major complications underwent distal embolization. There were more complications in patients who underwent distal embolization (24% distal vs 6% proximal alone; P = .02). Minor complications, which occurred in 34% of patients, included left-sided pleural effusions, coil migration, and fever. CONCLUSIONS: SAE is a useful tool for managing splenic injuries. Major and minor complications can occur. Distal embolization is associated with more major complications.

Column bioleaching of low-grade mining ore containing high level of smithsonite, talc, sphaerocobaltite and azurite.

Present work describes the bioleaching potential of metals from low-grade mining ore containing smithsonite, sphaerocobaltite, azurite and talc as main gangue minerals with adapted consortium of Sulfobacillus thermosulfidooxidans strain-RDB and Thermoplasma acidophilum. Bioleaching potential improved markedly by added energy source, acid preleaching and adaptation of microbial consortium with mixed metal ions. During whole leaching period including acid preleaching stage of 960 h and bioleaching stage of 212 days about 76% Co, 70% Zn, 84% Cu, 72% Ni and 63% Fe leached out.

Laparoscopic management of small bowel obstruction in children.

INTRODUCTION: The use of laparoscopy in the treatment of acute small bowel obstruction (SBO) faces inherent obstacles, including dilated loops of bowel, a limited working space, and postoperative adhesions. The objective of this study was to outline the efficacy of laparoscopic management of SBO in children. METHODS: With Institutional Review Board (IRB) approval, children who presented with a diagnosis of SBO and underwent management via a laparoscopic approach at our institution from January 2001 to December 2008 were retrospectively reviewed. Medical records were reviewed for age, weight, etiology of obstruction, radiographic findings, need for conversion, number of operations, length of stay, and postoperative complications. Statistical analyses of data comparison between those patients who were managed utilizing a laparoscopic approach and those in whom the laparoscopic approach was converted to a laparotomy were performed using a Chi-squared or a two-tailed Student's t-test with significance reported for P < 0.05. RESULTS: Thirty-four patients underwent laparoscopic management of SBO. Mean age was 8.1 ± 5.9 years with a mean weight of 32.8 ± 24.6 kg. Sixty-seven percent were male. A preoperative computed tomography scan was obtained in 21 patients (62%). Eleven cases (32%) required conversion to laparotomy. The most common reason for conversion to the open approach was poor working space (45.4%) followed by intestinal volvulus (27.2%), inability to identify source of obstruction (18.2%), and enterotomy (9%). The most common cause of SBO was postoperative adhesions (73.5%), followed by Meckel's diverticulum (8.8%), volvulus (8.8%), and other (8.8%). Postoperative complications occurred in 5 patients (14.7%). One patient died within 30 days of exploration due to intestinal ischemia secondary to midgut volvulus and subsequent septic shock. Five patients (14.7%) had a recurrent SBO with a mean time to recurrence of 2.6 ± 2.1 months. There were no significant differences in demographic or preoperative variables between patients who were successfully managed with laparoscopy alone versus those patients in whom conversion to laparotomy was necessary. In patients who required conversion, the laparoscopic evaluation did aid in identifying the etiology and allowed for a directed surgical approach when appropriate. CONCLUSIONS: Laparoscopy for the management of SBO in children is safe and can be therapeutic in the majority of patients. We recommend that consideration for initial exploration in children with SBO be carried out via the laparoscopic approach, with an understanding that conversion to an open approach may be necessary to complete the operation.