End-to-end anastomosis as a superior repair type to prevent recurrence of arteriovenous fistula aneurysms and improve patency outcomes.

BACKGROUND: Arteriovenous fistulae (AVF) complicated by aneurysms are repaired through several mechanisms. Little is known about risk factors for aneurysm recurrence or the efficacy of subsequent repair of recurring aneurysms. METHODS: About 291 patients underwent AVF aneurysm repair between 2009 and 2019 at a large urban medical center. Patients who underwent staged repair, had a primary graft with pseudoaneurysm, were status-post kidney transplant, or using other dialysis access at the time of repair were excluded. One hundred sixty-two patients were included in the study, of which 52 developed a secondary aneurysm. Chi-square and t-test analyses were used to compare demographics. Multivariate logistic regression was used to examine independent risk factors for aneurysm recurrence. Of the 52 patients with recurrent aneurysms, 41 were repaired again. Patency was examined for each group 1 year postoperatively. RESULTS: Patients without secondary aneurysms were more likely to have a Charlson Comorbidity Index score ⩾5 (p = 0.045). Males were 2.8 times more likely to develop a secondary aneurysm compared to females (p = 0.023). Patients who underwent elective compared to emergent or urgent surgery for primary aneurysms were significantly less likely to recur (OR = 0.222; p = 0.016). Primary aneurysms repaired by end-to-end anastomosis, compared to aneurysmorrhaphy or graft, were significantly less likely to recur (OR = 0.239; p = 0.041). Among patients with secondary aneurysms, those repaired via end-to-end anastomosis had a significantly higher primary patency rate 1 year postoperatively (p = 0.024). Secondary aneurysm repairs exhibited 1-year primary and secondary patency rates of 51.2% and 82.9%, respectively. CONCLUSIONS: End-to-end anastomosis reduces risk of recurrence and demonstrates superior patency rates when repairing recurrent aneurysms. It remains unclear why some patients are prone to aneurysm recurrence, however continued attempts to repair existing vascular access are proven to be successful.

Graft repair of arteriovenous fistula aneurysms is associated with decreased long-term patency.

INTRODUCTION: Arteriovenous fistula (AVF) aneurysms are a chronic complication which can be disfiguring, painful, and can rupture. Here, we compare the outcomes between three different methods of AVF aneurysm repair. METHODS: One-way ANOVA, Chi-square, and Fisher Exact analyses were used to compare demographics. Multivariate logistic regression compared outcomes. Kaplan-Meier estimate illustrated long-term fistula patency. RESULTS: There were no differences between demographics in the aneurysmorrhaphy, end-to-end anastomosis, and synthetic graft groups. The odds of patients who received graft repair losing primary patency within one year compared to the aneurysmorrhaphy group was 3.5 (p = 0.025). Graft repair patients were 6.7 times more likely to develop an infection compared to aneurysmorrhaphy (p = 0.014). Synthetic grafts also exhibited accelerated rates of complete access loss compared to autogenous methods (p = 0.034). CONCLUSIONS: Graft repair of AVF aneurysms results in higher rates of infection and decreased primary and ultimate patency compared to autogenous repair techniques. Therefore, synthetic grafts should be avoided whenever possible.

Acute Large Vessel Ischemic Stroke in Patients With COVID-19-Related Multisystem Inflammatory Syndrome.

BACKGROUND: Acute ischemic stroke (AIS) is rare in children, and diagnosis is often delayed. Neurological involvement may occur in multisystem inflammatory syndrome in children (MIS-C), but very few cases of AIS in patients with MIS-C have been reported. PATIENT DESCRIPTIONS: We two patients with AIS presenting with large vessel occlusive disease in previously healthy adolescents recently exposed to SARS-CoV-2 infection. RESULTS: Both patients were subsequently diagnosed with and treated for MIS-C. Here, we discuss the course of their treatments and clinical responses. CONCLUSION: Early recognition and diagnosis of AIS with large vessel occlusion in children with MIS-C is critical to make available all treatment options to improve clinical outcomes.

Patients With Combined Thermal and Intraabdominal Injuries: More Salvageable Than Not.

This study aims to better characterize the course and outcome of the uncommon subset of trauma patients with combined thermal and intraabdominal organ injuries. The National Trauma Data Bank was queried for burn patients with intraabdominal injury treated in all U.S. trauma centers from July 1, 2011 to June 30, 2015. General demographics, Glasgow coma scale (GCS), shock index (SI), Abbreviated Injury Scale (AIS) for burn, Injury Severity Score (ISS), blood transfusions, and abdominal surgery were evaluated. During the 5-year study period, there were 334 burn patients with intraabdominal injury, 39 (13.2%) of which received abdominal surgery. Burn patients who underwent operations had more severe injuries reflected by higher SI, AIS, ISS, blood transfusion, and worse outcomes including higher mortality, longer hospital and ICU length of stay, and more ventilator days compared to patients who did not undergo an operation. Nonsurvivors also exhibited more severe injuries, and a higher proportion received abdominal operation compared to survivors. Multivariate logistic regression analysis revealed that GCS on arrival, SI, AIS, ISS, blood transfusion, and abdominal operation to be independent risk factors for mortality. Propensity score matching to control covariables (mean age, systolic blood pressure on arrival, GCS on arrival, SI, ISS, time to operation, blood transfusion, and comorbidities) showed that of trauma patients who received abdominal operation, those with concomitant burn injury exhibited a higher rate of complications but no significant difference in mortality compared to those without burns, suggesting that patients with concomitant burns are not less salvageable than nonburned trauma patients.

Preoperative stimulation of resolution and inflammation blockade eradicates micrometastases.

Cancer therapy is a double-edged sword, as surgery and chemotherapy can induce an inflammatory/immunosuppressive injury response that promotes dormancy escape and tumor recurrence. We hypothesized that these events could be altered by early blockade of the inflammatory cascade and/or by accelerating the resolution of inflammation. Preoperative, but not postoperative, administration of the nonsteroidal antiinflammatory drug ketorolac and/or resolvins, a family of specialized proresolving autacoid mediators, eliminated micrometastases in multiple tumor-resection models, resulting in long-term survival. Ketorolac unleashed anticancer T cell immunity that was augmented by immune checkpoint blockade, negated by adjuvant chemotherapy, and dependent on inhibition of the COX-1/thromboxane A2 (TXA2) pathway. Preoperative stimulation of inflammation resolution via resolvins (RvD2, RvD3, and RvD4) inhibited metastases and induced T cell responses. Ketorolac and resolvins exhibited synergistic antitumor activity and prevented surgery- or chemotherapy-induced dormancy escape. Thus, simultaneously blocking the ensuing proinflammatory response and activating endogenous resolution programs before surgery may eliminate micrometastases and reduce tumor recurrence.

Suppression of chemotherapy-induced cytokine/lipid mediator surge and ovarian cancer by a dual COX-2/sEH inhibitor.

Although chemotherapy is a conventional cancer treatment, it may induce a protumorigenic microenvironment by triggering the release of proinflammatory mediators. In this study, we demonstrate that ovarian tumor cell debris generated by first-line platinum- and taxane-based chemotherapy accelerates tumor progression by stimulating a macrophage-derived "surge" of proinflammatory cytokines and bioactive lipids. Thus, targeting a single inflammatory mediator or pathway is unlikely to prevent therapy-induced tumor progression. Here, we show that combined pharmacological abrogation of the cyclooxygenase-2 (COX-2) and soluble epoxide hydrolase (sEH) pathways prevented the debris-induced surge of both cytokines and lipid mediators by macrophages. In animal models, the dual COX-2/sEH inhibitor PTUPB delayed the onset of debris-stimulated ovarian tumor growth and ascites leading to sustained survival over 120 days postinjection. Therefore, dual inhibition of COX-2/sEH may be an approach to suppress debris-stimulated ovarian tumor growth by preventing the therapy-induced surge of cytokines and lipid mediators.

Chemotherapy-generated cell debris stimulates colon carcinoma tumor growth via osteopontin.

Colon cancer recurrence after therapy, such as 5-fluorouracil (5-FU), remains a challenge in the clinical setting. Chemotherapy reduces tumor burden by inducing cell death; however, the resulting dead tumor cells, or debris, may paradoxically stimulate angiogenesis, inflammation, and tumor growth. Here, we demonstrate that 5-FU-generated colon carcinoma debris stimulates the growth of a subthreshold inoculum of living tumor cells in subcutaneous and orthotopic models. Debris triggered the release of osteopontin (OPN) by tumor cells and host macrophages. Both coinjection of debris and systemic treatment with 5-FU increased plasma OPN levels in tumor-bearing mice. RNA expression levels of secreted phosphoprotein 1, the gene that encodes OPN, correlate with poor prognosis in patients with colorectal cancer and are elevated in chemotherapy-treated patients who experience tumor recurrence vs. no recurrence. Pharmacologic and genetic ablation of OPN inhibited debris-stimulated tumor growth. Systemic treatment with a combination of a neutralizing OPN antibody and 5-FU dramatically inhibited tumor growth. These results demonstrate a novel mechanism of tumor progression mediated by OPN released in response to chemotherapy-generated tumor cell debris. Neutralization of debris-stimulated OPN represents a potential therapeutic strategy to overcome the inherent limitation of cytotoxic therapies as a result of the generation of cell debris.-Chang, J., Bhasin, S. S., Bielenberg, D. R., Sukhatme, V. P., Bhasin, M., Huang, S., Kieran, M. W., Panigrahy, D. Chemotherapy-generated cell debris stimulates colon carcinoma tumor growth via osteopontin.

Resolvins suppress tumor growth and enhance cancer therapy.

Cancer therapy reduces tumor burden by killing tumor cells, yet it simultaneously creates tumor cell debris that may stimulate inflammation and tumor growth. Thus, conventional cancer therapy is inherently a double-edged sword. In this study, we show that tumor cells killed by chemotherapy or targeted therapy ("tumor cell debris") stimulate primary tumor growth when coinjected with a subthreshold (nontumorigenic) inoculum of tumor cells by triggering macrophage proinflammatory cytokine release after phosphatidylserine exposure. Debris-stimulated tumors were inhibited by antiinflammatory and proresolving lipid autacoids, namely resolvin D1 (RvD1), RvD2, or RvE1. These mediators specifically inhibit debris-stimulated cancer progression by enhancing clearance of debris via macrophage phagocytosis in multiple tumor types. Resolvins counterregulate the release of cytokines/chemokines, including TNFα, IL-6, IL-8, CCL4, and CCL5, by human macrophages stimulated with cell debris. These results demonstrate that enhancing endogenous clearance of tumor cell debris is a new therapeutic target that may complement cytotoxic cancer therapies.