Modified Harborview Risk Score improves ease in predicting mortality after ruptured abdominal aortic aneurysm repair.

OBJECTIVE: The Harborview Risk Score (HRS) is a simple, accurate 4-point preoperative risk scoring system used to predict 30-day mortality following ruptured abdominal aortic aneurysm (rAAA) repair. The HRS assigns 1 point for each of the following: age >76 years, pH <7.2, creatinine >2 mg/dL, and any episode of severe hypotension (systolic blood pressure <70 mmHg). One potential limitation of this risk scoring system is that arterial blood gas (ABG) analysis is required to determine arterial pH. Because ABG analysis is not routinely performed prior to patient transfer or rAAA repair, we sought to determine if the HRS could be modified by replacing pH with the international normalized ratio (INR), a factor that has been previously shown to have a strong and independent association with 30-day death after rAAA repair. METHODS: A retrospective review of all rAAA repairs done at a single academic medical center between January 2002 and December 2018 was performed. Our traditional HRS was compared with a modified score, in which pH <7.2 was replaced with INR >1.8. Patients were included if they underwent rAAA repair (open or endovascular), and if they had preoperative laboratory values available to calculate both the traditional and modified HRS. RESULTS: During the 17-year study period, 360 of 391 repairs met inclusion criteria. Observed 30-day mortality using the modified scoring system was 17% (18/106) for a score of 0 points, 43% (53/122) for 1 point, 54% (52/96) for 2 points, 84% (27/32) for 3 points, and 100% (4/4) for 4 points. Receiver operating characteristic analysis revealed similar ability of the two scoring systems to predict 30-day death: there was no significant difference in the area under the curve (AUC) comparing the traditional (AUC = 0.74) and modified (AUC = 0.72) HRS (P = .3). CONCLUSIONS: Although previously validated among a modern cohort of patients with rAAA, our traditional 4-point risk score is limited in real-world use by the need for an ABG. Substituting INR for pH improves the usefulness of our risk scoring system without compromising accuracy in predicting 30-day mortality after rAAA repair.

Intraoperative consultation of vascular surgeons is increasing at a major American trauma center.

OBJECTIVE: Vascular surgeons are often called to aid other surgical specialties for complex exposure, hemorrhage control, or revascularization. The evolving role of the vascular surgeon in the management of intraoperative emergencies involving trauma patients remains undefined. The primary aims of this study included determining the prevalence of intraoperative vascular consultation in trauma, describing how these interactions have changed over time, and characterizing the outcomes achieved by vascular surgeons in these settings. We hypothesized that growing endovascular capabilities of vascular surgeons have resulted in an increased involvement of vascular surgery faculty in the management of the trauma patient over time. METHODS: A retrospective review of all operative cases at a single level I trauma center where a vascular surgeon was involved, but not listed as the primary surgeon, between 2002 and 2017 was performed. Cases were abstracted using Horizon Surgical Manager, a documentation system used in our operating room to track staff present, the type of case, and use. All elective cases were excluded. RESULTS: Of the 256 patients initially identified, 22 were excluded owing to the elective or joint nature of the procedure, leaving 234 emergent operative vascular consultations. Over the 15-year study period, a 529% increase in the number of vascular surgery consultations was seen, with 65% (n = 152) being intraoperative consultations requiring an immediate response. Trauma surgery (n = 103 [44%]) and orthopedic surgery (n = 94 [40%]) were the most common consulting specialties, with both demonstrating a trend of increasing consultations over time (general surgery, 1400%; orthopedic surgery, 220%). Indications for consultation were extremity malperfusion, hemorrhage, and concern for arterial injury. The average operative time for the vascular component of the procedures was 2.4 hours. Of patients presenting with ischemia, revascularization was successful in 94% (n = 116). Hemorrhage was controlled in 99% (n = 122). In-hospital mortality was relatively low at 7% (n = 17). Overall, despite the increase in intraoperative vascular consultations over time, a concomitant increase in the proportion of procedures done using endovascular techniques was not seen. CONCLUSIONS: Vascular surgeons are essential team members at a level I trauma center. Vascular consultation in this setting is often unplanned and often requires immediate intervention. The number of intraoperative vascular consultations is increasing and cannot be attributed solely to an increase in endovascular hemorrhage control, and instead may reflect the declining experience of trauma surgeons with vascular trauma. When consulted, vascular surgeons are effective in quickly gaining control of the situation to provide exposure, hemorrhage control, or revascularization.

Bilateral internal iliac branch device with ipsilateral deployment.

Iliac branch endograft devices offer an elegant solution to preserve perfusion to the internal iliac artery when treating aortoiliac aneurysms; however, they are difficult to perform when bilateral access is not available owing to aortoiliac anatomy or previous endovascular aortic aneurysm repair. We present a technique to perform iliac branch endograft deployment from ipsilateral access in a patient with a prior EVAR endovascular aortic aneurysm repair, obviating the need for a difficult up-and-over access.

Preoperative risk score accuracy confirmed in a modern ruptured abdominal aortic aneurysm experience.

OBJECTIVE: Various risk score calculators used to predict 30-day mortality after treatment of ruptured abdominal aortic aneurysms (rAAAs) have produced mixed results regarding their usefulness and reproducibility. We prospectively validated the accuracy of our preoperative scoring system in a modern cohort of patients with rAAAs. METHODS: A retrospective review of all patients wiith rAAAs who had presented to a single academic center from January 2002 to December 2018 was performed. The patients were divided into three cohorts according to when the institutional practice changes had occurred: the pre-endovascular aneurysm repair (EVAR) era (January 2002 to July 2007), the pre-Harbor View risk score era (August 2007 to October 2013), and the modern era (November 2013 to December 2018). The primary outcome measure was 30-day mortality. Our preoperative risk score assigns 1 point for each of the following: age >76 years, pH <7.2, creatinine >2 mg/dL, and any episode of hypotension (systolic blood pressure <70 mm Hg). The previously reported mortality from a retrospective analysis of the first two cohorts was 22% for 1 point, 69% for 2 points, 78% for 3 points, and 100% for 4 points. The goal of the present study was to prospectively validate the Harborview scoring system in the modern era. RESULTS: During the 17-year study period, 417 patients with rAAAs were treated at our institution. Of the 118 patients treated in the modern era, 45 (38.1%) had undergone open aneurysm repair (OAR), 61 (51.7%) had undergone EVAR, and 12 (10.2%) had received comfort measures only. Excluding the 12 patients without aneurysm repair, we found a statistically significant linear trend between the preoperative risk score and subsequent 30-day mortality for all patients combined (P < .0001), for OAR patients alone (P = .0003), and for EVAR patients alone (P < .0001). After adjustment for the Harborview risk score, the 30-day mortality was 41.3% vs 31.6% after OAR vs EVAR, respectively (P = .2). For all repairs, the 30-day mortality was 14.6% for a score of 0, 35.7% for a score of 1, 68.4% for a score of 2, and 100% for a score of 3 or 4. CONCLUSIONS: Our results, representing one of the largest modern series of rAAAs treated at a single institution, have confirmed the accuracy of a simple 4-point preoperative risk score in predicting 30-day mortality in the modern rAAA patient. Such tools should be used when discussing the treatment options with referring physicians, patients, and their family members to help guide transfer and treatment decision-making.

Initial experience with the Terumo aortic Treo device for fenestrated endovascular aneurysm repair.

OBJECTIVE: The Terumo aortic (TA) Treo device (Terumo, Somerset, NJ) is an endograft with unique features that lends itself to fenestrated endovascular aneurysm repair (FEVAR), including a low device profile, a wide amplitude stent design, and an increased interstent distance. We have described our initial experience with the Treo device for FEVAR to treat short neck and juxtarenal abdominal aortic aneurysms. METHODS: As part of an ongoing physician-sponsored investigational device exemption clinical trial (ClinicalTrials.gov identifier, NCT01538056), subjects were prospectively enrolled and underwent elective FEVAR using a variety of devices. Demographic and procedural details were collected. The data from subjects treated specifically with the Treo device from November 3, 2016 to May 2, 2019 were collected and analyzed. RESULTS: Of a cohort of 161 patients who had undergone elective FEVAR, 46 had been treated with the TA Treo device. Most patients were men (70%), with a mean age of 75 years and high rates of hypertension (74%), hyperlipidemia (83%), coronary artery disease (33%), and chronic obstructive pulmonary disease (33%). The mean aneurysm size was 66 mm, the mean preoperative infrarenal neck length was 5 mm, and the mean final seal zone length was 45 mm. The average hospital and intensive care unit lengths of stay were 2.4 and 1.5 days, respectively. A total of 129 fenestrations were created for 44 superior mesenteric and 85 renal arteries (2.8 fenestrations per patient). Technical success, defined as successful implantation of the device with all target vessels preserved, was 98% (45 of 46), with only one renal artery not successfully preserved. The mean follow-up period was 598 days. During the study period, 18 endoleaks were detected (17 type II and 1 type III), with one patient with a type III endoleak requiring reintervention. Three subjects had died within 30 days, one of intracranial hemorrhage, one of respiratory failure, and one of ischemic colitis. The graft modification times for the TA Treo were significantly shorter (43 minutes) than those for other commercially available devices (Cook Zenith, 55 minutes; Medtronic Endurant, 54 minutes; P < .0001). CONCLUSIONS: Our institution has reported exclusive worldwide experience using the TA Treo device for FEVAR. This device provides for a highly efficient and technically successful procedure for most patients. The procedural and fluoroscopy times were low even in the setting of high complexity. The technical success rates and simplification of the FEVAR procedure have made this approach a preferred technique for most patients at our institution.

Emerging practice patterns in vascular surgery during the COVID-19 pandemic.

OBJECTIVE: Ever since the first positive test was identified on January 21, 2020, Washington State has been on the frontlines of the coronavirus disease 2019 (COVID-19) pandemic. Using information obtained from Italian surgeons in Milan and given the concerns regarding the increasing case numbers in Washington State, we implemented new vascular surgery guidelines, which canceled all nonemergent surgical procedures and involved significant changes to our inpatient and outpatient workflow. The consequences of these decisions are not yet understood. METHODS: The vascular surgery division at Harborview Medical Center immediately instituted new vascular surgery COVID-19 practice guidelines on March 17, 2020. Subsequent clinic, operative, and consultation volume data were collected for the next 4 weeks and compared with the historical averages. The Washington State case and death numbers and University of Washington Medical Center (UW Medicine) hospital case volumes were collected from publicly available sources. RESULTS: Since March 10, 2020, the number of confirmed positive COVID-19 cases within the UW Medicine system has increased 1867%, with floor and intensive care unit bed usage increasing by 120% and 215%, respectively. After instituting our new COVID-19 guidelines, our average weekly clinical volume decreased by 96.5% (from 43.1 patients to 1.5 patients per week), our average weekly surgical volume decreased by 71.7% (from 15 cases to 4.25 cases per week), and our inpatient consultation volume decreased to 1.81 consultations daily; 60% of the consultations were completed as telemedicine "e-consults" in which the patient was never evaluated in-person. The trainee surgical volume has also decreased by 86.4% for the vascular surgery fellow and 84.8% for the integrated resident. CONCLUSIONS: The COVID-19 pandemic has changed every aspect of "normal" vascular surgical practice in a large academic institution. New practice guidelines effectively reduced operating room usage and decreased staff and trainee exposure to potential infection, with the changes to clinic volume not resulting in an immediate increase in emergency department or inpatient consultations or acute surgical emergencies. These changes, although preserving resources, have also reduced trainee exposure and operative volume significantly, which requires new modes of education delivery. The lessons learned during the COVID-19 pandemic, if analyzed, will help us prepare for the next crisis.

APOE3, but not APOE4, bone marrow transplantation mitigates behavioral and pathological changes in a mouse model of Alzheimer disease.

Apolipoprotein E4 (APOE4) genotype is the strongest genetic risk factor for late-onset Alzheimer disease and confers a proinflammatory, neurotoxic phenotype to microglia. Here, we tested the hypothesis that bone marrow cell APOE genotype modulates pathological progression in experimental Alzheimer disease. We performed bone marrow transplants (BMT) from green fluorescent protein-expressing human APOE3/3 or APOE4/4 donor mice into lethally irradiated 5-month-old APPswe/PS1ΔE9 mice. Eight months later, APOE4/4 BMT-recipient APPswe/PS1ΔE9 mice had significantly impaired spatial working memory and increased detergent-soluble and plaque Aß compared with APOE3/3 BMT-recipient APPswe/PS1ΔE9 mice. BMT-derived microglia engraftment was significantly reduced in APOE4/4 recipients, who also had correspondingly less cerebral apoE. Gene expression analysis in cerebral cortex of APOE3/3 BMT recipients showed reduced expression of tumor necrosis factor-α and macrophage migration inhibitory factor (both neurotoxic cytokines) and elevated immunomodulatory IL-10 expression in APOE3/3 recipients compared with those that received APOE4/4 bone marrow. This was not due to detectable APOE-specific differences in expression of microglial major histocompatibility complex class II, C-C chemokine receptor (CCR) type 1, CCR2, CX3C chemokine receptor 1 (CX3CR1), or C5a anaphylatoxin chemotactic receptor (C5aR). Together, these findings suggest that BMT-derived APOE3-expressing cells are superior to those that express APOE4 in their ability to mitigate the behavioral and neuropathological changes in experimental Alzheimer disease.

Ablation of the microglial protein DOCK2 reduces amyloid burden in a mouse model of Alzheimer's disease.

Alzheimer's disease (AD) neuropathology is characterized by innate immune activation primarily through prostaglandin E2 (PGE2) signaling. Dedicator of cytokinesis 2 (DOCK2) is a guanyl nucleotide exchange factor expressed exclusively in microglia in the brain and is regulated by PGE2 receptor EP2. DOCK2 modulates microglia cytokine secretion, phagocytosis, and paracrine neurotoxicity. EP2 ablation in experimental AD results in reduced oxidative damage and amyloid beta (Aß) burden. This discovery led us to hypothesize that genetic ablation of DOCK2 would replicate the anti-Aß effects of loss of EP2 in experimental AD. To test this hypothesis, we crossed mice that lacked DOCK2 (DOCK2-/-), were hemizygous for DOCK2 (DOCK2+/-), or that expressed two DOCK2 genes (DOCK2+/+) with APPswe-PS1Δe9 mice (a model of AD). While we found no DOCK2-dependent differences in cortex or in hippocampal microglia density or morphology in APPswe-PS1Δe9 mice, cerebral cortical and hippocampal Aß plaque area and size were significantly reduced in 10-month-old APPswe-PS1Δe9/DOCK2-/- mice compared with APPswe-PS1Δe9/DOCK2+/+ controls. DOCK2 hemizygous APPswe-PS1Δe9 mice had intermediate Aß plaque levels. Interestingly, soluble Aß42 was not significantly different among the three genotypes, suggesting the effects were mediated specifically in fibrillar Aß. In combination with earlier cell culture results, our in vivo results presented here suggest DOCK2 contributes to Aß plaque burden via regulation of microglial innate immune function and may represent a novel therapeutic target for AD.