In Vivo Porcine Model of Acute Iliocaval Deep Vein Thrombosis.

CLINICAL IMPACT: The study establishes a rapid, technically straightforward, and reproducible porcine large animal model for acute iliocaval deep vein thrombosis (DVT). The procedure can be performed with basic endovascular skillsets. With its procedural efficiency and consistency, the platform is promising for comparative in vivo testing of venous thrombectomy devices in a living host, and for future verification and validation studies to determine efficacy of novel thrombectomy devices relative to predicates.

Quantitative Assessment of Peripheral Oxidative Metabolism With a New Dynamic 1 H MRI Technique: A Pilot Study in People With and Without Diabetes Mellitus.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is linked to impaired mitochondrial function. Chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) is a gadolinium-contrast-free 1 H method to assess mitochondrial function by measuring low-concentration metabolites. A CEST MRI-based technique may serve as a non-invasive proxy for assessing mitochondrial health. HYPOTHESIS: A 1 H CEST MRI technique may detect significant differences in in vivo skeletal muscle phosphocreatine (SMPCr) kinetics between healthy volunteers and T2DM patients undergoing standardized isometric exercise. STUDY TYPE: Cross-sectional study. SUBJECTS: Seven subjects without T2DM (T2DM-) and seven age, sex, and BMI-matched subjects with T2DM (T2DM+). FIELD STRENGTH/SEQUENCE: Single-shot rapid acquisition with refocusing echoes (RARE) and single-shot gradient-echo sequences, 3 T. ASSESSMENT: Subjects underwent a rest-exercise-recovery imaging protocol to dynamically acquire SMPCr maps in calf musculature. Medial gastrocnemius (MG) and soleus SMPCr concentrations were plotted over time, and SMPCr recovery time, τ $$ \tau $$ , was determined. Mitochondrial function index was calculated as the ratio of resting SMPCr to τ $$ \tau $$ . Participants underwent a second exercise protocol for imaging of skeletal muscle blood flow (SMBF), and its association with SMPCr was assessed. STATISTICAL TESTS: Unpaired t-tests and Pearson correlation coefficient. A P value <0.05 was considered statistically significant. RESULTS: SMPCr concentrations in MG and soleus displayed expected declines during exercise and returns to baseline during recovery. τ $$ \tau $$ was significantly longer in the T2DM+ cohort (MG 83.5 ± 25.8 vs. 54.0 ± 21.1, soleus 90.5 ± 18.9 vs. 51.2 ± 14.5). The mitochondrial function index in the soleus was significantly lower in the T2DM+ cohort (0.33 ± 0.08 vs. 0.66 ± 0.19). SMBF was moderately correlated with the SMPCr in T2DM-; this correlation was not significant in T2DM+ (r = -0.23, P = 0.269). CONCLUSION: The CEST MRI method is feasible for quantifying SMPCr in peripheral muscle tissue. T2DM+ individuals had significantly lower oxidative capacities than T2DM- individuals. In T2DM, skeletal muscle metabolism appeared to be decoupled from perfusion. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 1.

Regional skeletal muscle perfusion distribution in diabetic feet may differentiate short-term healed foot ulcers from non-healed ulcers.

OBJECTIVES: The purpose of this study was to leverage a magnetic resonance imaging (MRI) approach to characterize foot perfusion distribution in patients with diabetes, with or without foot ulcers, and determine the ability of the regional perfusion measurements to identify ulcer-healing status. METHODS: Three groups of participants (n = 15 / group) were recruited: controls (without diabetes), type II diabetes, and type II diabetes with foot ulcers. All participants underwent MRI evaluating foot perfusion in three muscle layers (from plantar to dorsal) at rest and during a standardized toe-flexion exercise. The exercise perfusion and perfusion reserve values were analyzed around and away from ulcers. Participants with foot ulcers were followed up 3 months after the MRI exams to determine the foot healing status. RESULTS: Foot plantar muscle perfusion reserves were progressively lower from controls to diabetes, and to diabetes with foot ulcers (e.g., 2.58 ± 0.67, 1.48 ± 0.71, 1.12 ± 0.35, p < 0.001). In controls, the plantar layer had significantly higher perfusion reserve than the dorsal layer, whereas in either diabetes group, there was no significant difference in perfusion reserve among muscle layers. Using the ratio of total exercise perfusion around ulcers to that away from ulcers, the sensitivity and specificity to differentiate healing from non-healed ulcers were 100% and 86%, respectively. CONCLUSIONS: Our study reveals significantly different foot perfusion distribution among controls, diabetes, and diabetes with foot ulcers. The prognostic value of MRI regional perfusion assessments has the potential to monitor interventions to improve ulcer healing outcomes. KEY POINTS: • Contrast-free MRI permits quantitative assessment of regional foot muscle perfusion at rest and during isometric exercise. • Patients with diabetes and foot ulcers, without clinical evidence of peripheral arterial disease, had significantly impaired foot muscle perfusion and perfusion reserve. • Regional foot perfusion distribution may be used to predict the short-term healing status of foot ulcers in diabetes.

Chronic anti-coagulation therapy reduced mortality in patients with high cardiovascular risk early in COVID-19 pandemic.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is associated with provoked thrombo-inflammatory responses. Early in the COVID-19 pandemic this was thought to contribute to hypercoagulability and multi-organ system complications in infected patients. Limited studies have evaluated the impact of therapeutic anti-coagulation therapy (AC) in alleviating these risks in COVID-19 positive patients. Our study aimed to investigate whether long-term therapeutic AC can decrease the risk of multi-organ system complications (MOSC) including stroke, limb ischemia, gastrointestinal (GI) bleeding, in-hospital and intensive care unit death in COVID-19 positive patients hospitalized during the early phase of the pandemic in the United States. METHODS: A retrospective analysis was conducted of all COVID-19 positive United States Veterans between March 2020 and October 2020. Patients receiving continuous outpatient therapeutic AC for a least 90 days prior to their initial COVID-19 positive test were assigned to the AC group. Patients who did not receive AC were included in a control group. We analyzed the primary study outcome of MOSC between the AC and control groups using binary logistic regression analysis (Odd-Ratio; OR). RESULTS: We identified 48,066 COVID-19 patients, of them 879 (1.8%) were receiving continuous therapeutic AC. The AC cohort had significantly worse comorbidities than the control group. On the adjusted binary logistic regression model, therapeutic AC significantly decreased in-hospital mortality rate (OR; 0.67, p = 0.04), despite a higher incidence of GI bleeding (OR; 4.00, p = 0.02). However, therapeutic AC did not significantly reduce other adverse events. CONCLUSION: AC therapy reduced in-hospital death early in the COVID-19 pandemic among patients who were hospitalized with the infection. However, it did not decrease the risk of MOSC. Additional trials are needed to determine the effectiveness of AC in preventing complications associated with ongoing emerging strains of the COVID-19 virus.

Impact of N-Acetyl-Cysteine on Ischemic Stumps Following Major Lower Extremity Amputation: A Pilot Randomized Clinical Trial.

OBJECTIVE: To evaluate the impact of N-acetyl-cysteine (NAC) on amputation stump perfusion and healing in patients with critical limb-threatening ischemia (CLTI). BACKGROUND: Patients with CLTI are at increased risk of poor amputation site healing leading to increased procedure-associated morbidity. METHODS: In a pilot, double-blind, placebo-controlled, randomized controlled trial, patients with CLTI undergoing major elective lower extremity amputation were randomized 1:1 to intravenous NAC (1200 mg twice-daily) or placebo for up to 5 days postoperatively. Primary outcomes were change in stump perfusion at postoperative day 3 (POD3) and POD5, and healing at POD30. Stumps were serially evaluated for wound healing, and tissue perfusion was evaluated using noninvasive laser-assisted fluorescent angiography. RESULTS: Thirty-three patients were randomized to NAC (n = 16) or placebo (n = 17). Thirty-one patients were eligible for intent-to-treat analysis (NAC14; placebo17). Twenty patients (NAC7; placebo13) had amputation stump perfusion defects at POD0 and were considered high-risk for poor healing. Intent-to-treat analysis revealed no significant differences between treatment groups. Subgroup analysis of high-risk patients revealed differences in stump perfusion defect size (NAC-0.53-fold, placebo +0.71-fold; 95% confidence interval -2.11 to-0.35; P < 0.05) and healing (NAC [100%], placebo [46%]; P < 0.01) between study treatments. CONCLUSIONS: Postoperative NAC administration may improve amputation stump perfusion and healing in patients with CLTI and tissue perfusion defects at the time of amputation. Intraoperative laser-assisted fluorescent angiogra-phy may help surgeons identify high-risk patients with stump perfusion defects and provide early adjunctive interventions. Future studies can further explore the therapeutic benefits of NAC in the healing and perfusion of other surgical operative sites in high-risk individuals. TRIAL REGISTRATION: clinicaltrials.gov, Identifier: NCT03253328.

Non-Enzymatic Phenylboronic Acid-Based Optode Membrane for Glucose Monitoring in Serums of Diabetic Patients and in the Culture Medium of Human Embryos.

Monitoring glucose levels is important not only for diabetics, but also for tracking embryonic development in human embryo culture media. In this study, an optochemical sensor (glucose-selective polymer membrane) was fabricated for the determination of glucose in serum from diabetic patients and the culture media of human embryos. The optode membranes were formulated using polyvinyl chloride (PVC) as the polymer matrix and 4',5'-dibromofluorescein octadecyl ester (ETH 7075) as the chromoionophore. The sensitivity of the optode membranes was optimized using two different plasticizers (tricresyl phosphate-TCP and nitrophenyloctyl ether-NOPE) and three ionophores (nitrophenylboronic acid-NPBA, trifluorophenyboronic acid-TFPBA, 4'-nitrobenzo-15-crown-5) and tested for glucose detection. The best optode membrane was formulated from 49.5% PVC, 49.5% TCP, 1% NPBA, and 1% ETH 7075. It showed a linear dynamic range of 10-3 M to 10-1 M, with a detection limit of 9 × 10-4 M and a response time of 2 min. The detection mechanism involves H-bonding between NPBA and glucose, which was confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR). The reaction also involves the formation of boronate esters in basic media with deprotonation of the chromoionophore (ETH 7075), leading to a decrease in UV-Vis absorbance at λmax = 530 nm. The membrane optode was used for glucose determination in synthetic culture medium, commercial embryo culture medium (GLOBAL® TOTAL® W/HEPES), and serum from normal and diabetic patients, showing good accuracy and precision of the optode.

Literature review and meta-analysis of the efficacy of cilostazol on limb salvage rates after infrainguinal endovascular and open revascularization.

BACKGROUND: Current clinical guidelines recommend the use of cilostazol in the treatment of patients with infrainguinal peripheral artery disease (PAD) who experience intermittent claudication. However, the role of cilostazol therapy in patients with advanced PAD and critical limb ischemia (CLI) remains unclear. To conduct a meta-analysis of randomized controlled trials and cohort studies that evaluated the effect of cilostazol vs standard antiplatelet therapy on limb-related and arterial patency-related outcomes. We also reviewed literature pertinent to the effect of cilostazol on wound healing in patients with advanced PAD. METHODS: We performed a MEDLINE, EMBASE, COCHRANE (CENTRAL), SCOPUS, and US Clinical Trials database search for all trials and studies since 1999 that compared cilostazol with standard antiplatelet therapy in the setting of infrainguinal PAD revascularization procedures (endovascular or open). Aggregate data was collected from four randomized control trials and six retrospective cohort studies. The end point incidence ratios and treatment effects were generated from each study and reported as hazard ratios (HR) using a random-effect model. We also reviewed 10 studies that evaluated the effect of cilostazol on wound healing in patients with advanced PAD. RESULTS: From more than 25,000 total patients, 3136 patients met our inclusion criteria. All patients had at least lifestyle-impacting intermittent claudication, and more than 50% met the definition of CLI (Rutherford class ≥4). Patient age range was 53 to 83 years, and the majority were male (66%). The mean follow-up time averaged 2 years across all studies. Meta-analysis revealed that cilostazol treatment favored amputation-free survival (hazard ratio [HR], 0.79; 95% confidence interval [CI], 0.69-0.91), limb salvage rate (HR, 0.42; 95% CI, 0.27-0.66), decreased repeat revascularization (risk ratio [RR], 0.44; 95% CI, 0.37-0.52), and decreased restenosis (RR, 0.68; 95% CI, 0.61-0.76). Cilostazol treatment also increased freedom from target lesion revascularization (RR, 1.35; 95% CI, 1.21-1.53) with no difference in all-cause mortality. Effective wound healing was found to be an inconsistent outcome measure in patients receiving cilostazol therapy. CONCLUSIONS: We observed that cilostazol therapy has a beneficial impact on all limb-related and arterial patency-related outcomes, but no effect on all-cause mortality in patients with advanced PAD and CLI undergoing revascularization procedures. Additional studies are needed to evaluate the effect of cilostazol therapy on wound healing in patients with advanced PAD.

Endovascular Removal of Thrombus and Right Heart Masses Using the AngioVac System: Results of 234 Patients from the Prospective, Multicenter Registry of AngioVac Procedures in Detail (RAPID).

PURPOSE: To assess device and procedural safety and technical success associated with the use of the AngioVac System to remove vascular thrombi and cardiac masses. MATERIALS AND METHODS: The Registry of AngioVac Procedures in Detail (RAPID) study prospectively collected data for 234 patients receiving treatment with AngioVac at 21 sites between March 2016 and August 2019: 84 (35.9%) with caval thromboemboli (CTEs), 113 (48.3%) with right heart masses (RHMs), 20 (8.5%) with catheter-related thrombi (CRTs), and 4 (1.7%) with pulmonary emboli (PEs). Thirteen patients had a combination of procedures during the same admission. RESULTS: Using the AngioVac system, 70%-100% thrombus or mass removal was achieved in 73.6% of patients with CTEs, 58.5% of patients with RHMs, 60% of patients with CRTs, and 57.1% of patients with PEs. Extracorporeal bypass time was < 1 hour for 176 (75.2%) procedures. Estimated blood loss was < 250 mL for 179 procedures (76.5%). Mean hemoglobin decreased from 10.4 g/dL ± 2.9 preoperatively to 9.4 g/dL ± 2.6 postoperatively. Transfusions were administered in 59 procedures (25.2%) with 47 transfusions (78.2%) being ≤ 2 U. There were 36 procedure-related complications, including 1 death. CONCLUSIONS: The RAPID registry data demonstrate that the AngioVac System can be safely and effectively used to remove vascular thrombi and cardiac masses across a broad range of patient populations. The limited use of the device to remove pulmonary emboli in the present series precludes recommending the use of the AngioVac device for this indication.

Pilot study of contrast-free MRI reveals significantly impaired calf skeletal muscle perfusion in diabetes with incompressible peripheral arteries.

Patients with diabetes mellitus (DM) are more likely to have densely calcified lesions in the below-the-knee tibial arteries. However, the relationship between peripheral arterial calcification and local skeletal muscle perfusion has not been explored. Thirty subjects were prospectively recruited into three groups in this pilot study: (1) Non-DM: 10 people without DM; (2) DM, ABI < 1.3: 10 people with DM and normal ankle-brachial index (ABI) (0.9-1.3); and (3) DM, ABI ⩾ 1.3: 10 people with DM and ABI ⩾ 1.3. All subjects underwent calf perfusion measurements at rest and during an isometric plantarflexion contraction exercise within the magnetic resonance imaging (MRI) system. The noncontrast MRI techniques were applied to quantitatively assess skeletal muscle blood flow (SMBF) and oxygen extraction fraction (SMOEF) in medial gastrocnemius and soleus muscles. Both SMBF and SMOEF reserves were calculated as the ratio of the exercise value to the resting value. Exercise SMBF and SMOEF values in the medial gastrocnemius muscle were lower in the two DM groups than in the non-DM group (p < 0.05). The SMBF reserve in medial gastrocnemius was significantly lower in the DM, ABI ⩾ 1.3 group compared to the DM, ABI < 1.3 group (p < 0.05). This study demonstrates that people with DM and calcified arteries had lower perfusion in gastrocnemius muscle compared to those without DM and those with DM and a normal ABI.

Canagliflozin impedes ischemic hind-limb recovery in the setting of diabetes.

There is a reported increased incidence of lower extremity amputations in individuals with diabetes who are treated with canagliflozin (an SGLT2 receptor inhibitor). It is unclear whether this is an unintended consequence of therapy, or whether canagliflozin can affect peripheral limb perfusion in the setting of underling arterial malperfusion. To evaluate this we explored the effect of canagliflozin on tissue recovery following unilateral hind-limb ischemia (HLI). Adult wildtype (+/+) and diabetic (db/db) mice were maintained on 8 weeks of a regular chow diet, or a chow diet containing canagliflozin (200 mg/kg). Following HLI, hind-limb appearance, function, and Doppler perfusion were serially evaluated. Gastrocnemius muscle fiber size and microvessel density were also evaluated 21 days following HLI. We observed that db/db that received a diet containing canagliflozin had significantly worse hind-limb function and appearance scores compared to both db/db mice that received a regular diet and +/+ mice that received a canagliflozin diet. At post-HLI day 21, db/db mice that received a canagliflozin diet also had decreased Doppler perfusion, gastrocnemius muscle fiber size, and microvessel density compared to +/+ mice that received a canagliflozin diet. These findings indicate that canagliflozin appears to impede ischemic peripheral tissue recovery and warrant further clinical investigation in individuals with diabetes and a history of peripheral artery disease.

Comprehensive Assessment of Current Management Strategies for Patients With Diabetes and Chronic Limb-Threatening Ischemia.

Chronic limb-threatening ischemia (CLTI) is the most severe form of peripheral artery disease. It is estimated that 60% of all nontraumatic lower-extremity amputations performed annually in the United States are in patients with diabetes and CLTI. The consequences of this condition are extraordinary, with substantial patient morbidity and mortality and high socioeconomic costs. Strategies that optimize the success of arterial revascularization in this unique patient population can have a substantial public health impact and improve patient outcomes. This article provides an up-to-date comprehensive assessment of management strategies for patients afflicted by both diabetes and CLTI.

Intravenous contrast-free standardized exercise perfusion imaging in diabetic feet with ulcers.

BACKGROUND: Impaired foot perfusion is a primary contributor to foot ulcer formation. There is no existing device nor method that can be used to measure local foot perfusion during standardized foot muscle exercise in an MRI environment. PURPOSE: To develop a new MRI-compatible foot dynamometer and MRI methods to characterize local perfusion in diabetic feet with ulcers. STUDY TYPE: Prospective. POPULATION/SUBJECTS: Seven participants without diabetes and 10 participants with diabetic foot ulcers. FIELD STRENGTH/SEQUENCE: 3.0T, arterial spin labeling (ASL). ASSESSMENTS: Using a new MRI-compatible foot dynamometer, all participants underwent MRI ASL perfusion assessment at rest and during a standardized toe-flexion exercise. The participants without diabetes were scanned twice to assess the reproducibility of perfusion measurements. The absolute perfusion and perfusion reserve values were compared between two groups and between regions near ulcers (peri-ulcer) and away from ulcers (away-ulcer). STATISTICAL TESTS: Bland-Altman methods for the calculation of coefficient of repeatability (CR) and two-sided and unpaired Student's t-test to compare multiple differences. RESULTS: The perfusion reserves measured had the best reproducibility (CR in medial region: 1.6, lateral region: 0.9). The foot perfusion reserve was significantly lower in the participants with diabetes compared with the participants without diabetes (1.34 ± 0.32, 95% confidence interval [CI]: 1.1, 1.58 vs. 1.76 ± 0.31, 95% CI: 1.53, 1.98, P = 0.02). Both peri-ulcer exercise perfusion (8.7 ± 3.9 ml/min/100g) and perfusion reserve (1.07 ± 0.39, 95% CI: 0.78, 1.35) were significantly lower than away-ulcer exercise perfusion (12.7 ± 3.8 ml/min/100g, P = 0.02) and perfusion reserve (1.39 ± 0.37, 95% CI: 1.11, 1.66, P = 0.03), respectively. DATA CONCLUSION: This study demonstrates intravenous contrast-free methods for local perfusion in feet with ulcers by standardized exercise-based MRI. Ischemia regions around foot ulcers can be quantitatively distinguished from normal perfused muscle regions. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:474-480.

Postoperative Low-Dose Heparin Infusion Does Not Change Complication Rates after Limb Revascularization.

BACKGROUND: Postoperative subtherapeutic low-dose heparin infusion (LDHI) is sometimes administered in patients undergoing extremity arterial revascularization to maintain graft patency and decrease the risk of thrombosis. However, the safety of this management strategy is unknown. METHODS: From 2013 to 2015, we retrospectively reviewed all patients undergoing upper and lower extremity arterial revascularization at a single university-affiliated medical center. Patients were grouped by receipt of LDHI within the first 24-hour postoperative period. Preoperative demographics, comorbidities, intraoperative measures, 30-day postoperative complications, arterial patency rates, and amputation rates were analyzed for each group. RESULTS: We identified 379 patients who received extremity revascularization, and 56 (14.8%) of them had received LDHI. Patients who received LDHI were less likely to have an elective admission on presentation (26.8% vs. 56%, P < 0.001) or an admission from home (69.6% vs. 81.7%, P = 0.04). They were more likely to have preoperative bleeding (44.6% vs. 22%, P < 0.01) and need for emergent operation (23.2% vs. 11.8%, P = 0.04). Postoperatively, although patients who received LDHI demonstrated a trend toward increased bleeding (48.2% vs. 33.7%, P = 0.053), they did not demonstrate an increase in 30-day mortality (1.79% vs. 1.24%, P = 0.55) or reoperation (19.7% vs. 12.4%, P = 0.21). Multivariable analysis demonstrated that LDHI did not have a significant association with immediate postoperative bleeding (P = 0.99), survival (P = 0.13), primary patency (P = 0.872), and amputation-free survival (P = 0.387). CONCLUSIONS: Although LDHI was more likely to be administered in patients who received emergent operations, risk-adjusted analysis demonstrated that it was not associated with increased postoperative bleeding, mortality, short-term need for reintervention, or amputation after extremity arterial revascularization.

Diabetes adversely affects phospholipid profiles in human carotid artery endarterectomy plaques.

Patients with diabetes are at higher risk of developing carotid artery stenosis and resultant stroke. Arachidonoyl phospholipids affect plaque inflammation and vulnerability, but whether diabetic patients have unique carotid artery phospholipidomic profiles is unknown. We performed a comprehensive paired analysis of phospholipids in extracranial carotid endarterectomy (CEA) plaques of matched diabetic and nondiabetic patients and analyzed mass spectrometry-derived profiles of three phospholipids, plasmenyl-phosphatidylethanolamine (pPE), phosphatidylserine (PS), and phosphatidylinositol (PI), in maximally (MAX) and minimally (MIN) diseased CEA segments. We also measured levels of arachidonic acid (AA), produced by pPE hydrolysis, and choline-ethanolamine phosphotransferase 1 (CEPT1), responsible for most pPE de novo biosynthesis. In paired analysis, MIN CEA segments had higher levels than MAX segments of pPE (P < 0.001), PS (P < 0.001), and PI (P < 0.03). MIN diabetic plaques contained higher levels than MAX diabetic plaques of arachidonoyl pPE38:4 and pPE38:5 and CEPT1 was upregulated in diabetic versus nondiabetic plaques. AA levels were relatively greater in MIN versus MAX segments of all CEA segments, and were higher in diabetic than nondiabetic plaques. Our findings suggest that arachidonoyl phospholipids are more likely to be abundant in the extracranial carotid artery plaque of diabetic rather than nondiabetic patients.

N-Acetylcysteine accelerates amputation stump healing in the setting of diabetes.

Over 60% of lower extremity amputations are performed in patients with diabetes and peripheral arterial disease, and at least 25% require subsequent reamputation due to poor surgical site healing. The mechanisms underlying poor amputation stump healing in the setting of diabetes are not understood. N-acetylcysteine (NAC) is known to promote endothelial cell function and angiogenesis and may have therapeutic benefits in the setting of diabetes. We tested the hypothesis that NAC alters the vascular milieu to improve healing of amputation stumps in diabetes using a novel in vivo murine hindlimb ischemia-amputation model. Amputation stump tissue perfusion and healing were evaluated in C57BL/6J adult mice with streptozotocin-induced diabetes. Compared with controls, mice treated with daily NAC demonstrated improved postamputation stump healing, perfusion, adductor muscle neovascularization, and decreased muscle fiber damage. Additionally, NAC stimulated HUVEC migration and proliferation in a phospholipase C ß-dependent fashion and decreased Gαq palmitoylation. Similarly, NAC treatment also decreased Gαq palmitoylation in ischemic and nonischemic hindlimbs in vivo In summary, we demonstrate that NAC accelerates healing of amputation stumps in the setting of diabetes and ischemia. The underlying mechanism appears to involve a previously unrecognized effect of NAC on Gαq palmitoylation and phospholipase C ß-mediated signaling in endothelial cells.-Zayed, M. A., Wei, X., Park, K., Belaygorod, L., Naim, U., Harvey, J., Yin, L., Blumer, K., Semenkovich, C. F. N-acetylcysteine accelerates amputation stump healing in the setting of diabetes.

Evaluation of planned bicanalicular nasolacrimal tube retention in treating punctal stenosis or occlusion secondary to trachoma.

This article evaluates retaining bicanalicular silicone nasolacrimal tube in patients susceptible to restenosis after punctoplasty. Sixty-nine eyes (38 patients) suffering from epiphora due to stenosis or occlusion of both punctae were included in this prospective study. All had 3 snip punctoplasty and bicanalicular silicone nasolacrimal duct insertion. Cases associated with proximal canalicular stenosis or obstructions were excluded. Tolerance to tube presence until the time of loss or removal was evaluated using a score (0 to 2). Average age was 49.71 ± 11.09 years. Tachomatous lesions were detected in all cases of punctal stenosis (48 eyes/69.57%) and membranous occlusion (21 eyes/30.43%). Common canalicular obstruction was additionally found in 12 eyes (17.39%). Absolute improvement was detected in 85% of cases and mean time for tube retention was (29.6 ± 10.2 months) with no difference in presence of common canalicular obstruction (P value: 0.138). Isolated punctal affection favoured tube retention that was well tolerated throughout the follow-up period (P value <0.001). Silicone bicanalicular nasolacrimal tube is an available option for treating acquired punctal stenosis. It is tolerated especially in cases suffering from isolated punctal stenosis. Tube retention could be of value in patients who are at risk of re-occlusion following tube removal.

A telephone call 1 week after hospitalization can identify risk factors for vascular surgery readmission.

OBJECTIVE: Compared with other populations, patients who undergo vascular surgery have higher 30-day hospital readmission rates of up to 25%. Postdischarge telephone call assessments have demonstrated utility in patients with significant medical comorbidities and traditionally high readmission rates. Therefore, we hypothesized that a 1-week postdischarge telephone call evaluation can identify risk factors for readmission among vascular surgery patients. METHODS: Patients who underwent a vascular surgery procedure during a 1-year period by a single vascular surgeon at one hospital received a postdischarge telephone call questionnaire to review postoperative pain, surgical site, constitutional symptoms, and follow-up arrangement. The primary outcome measure was frequency of postoperative symptoms as collected on the telephone call questionnaire. The secondary outcome measure was 30-day hospital readmission rates. RESULTS: Among 167 patients, 131 (78%) received a telephone call after discharge. Calls identified pain relieved by prescription medication (odds ratio, 6.67; confidence interval, 0.82-53.81; P = .05) and continued dressing application (odds ratio, 9.55; confidence interval, 0.54-166.6; P = .04) as risk factors for 30-day readmission. The 30-day readmission was not statistically different in patients who were successfully and not successfully contacted with a postdischarge telephone call (8% and 17%, respectively; P = .37). CONCLUSIONS: Vascular surgery patients are at higher risk of 30-day readmission than are patients in other surgical subspecialties. For the majority of patients, implementing a 1-week postdischarge telephone call for short-term follow-up evaluation is feasible and can help identify potential risk factors for hospital readmission within 30 days.

Plug the Hole--A Bailout Option for Acute Focal Aortic Rupture.

BACKGROUND: Focal aortic rupture may result from expanding aneurysms, penetrating aortic wall ulcerations, or virulent infections. An urgent repair of paravisceral focal aortic rupture is associated with high morbidity. A staged repair approach may provide an alternative option. CASE REPORT: A 64-year-old woman presented with acute focal rupture of the posterior paravisceral aortic wall and was progressing to hemorrhagic shock and mesenteric ischemia. Given the patient's dire condition, an endovascular approach was used to plug her focal aortic wall defect using a ventricular septal defect occluder device. Subsequently, the patient underwent resuscitation, stabilization, and operative exploration. Postoperatively, she recovered well from this staged approach. CONCLUSIONS: This case provides an example of a staged endovascular plugging of an acute paravisceral focal aortic rupture. In select cases, this type of repair strategy is feasible, until off-the-shelf endovascular repair options become a reality.

Novel Use of Google Glass for Procedural Wireless Vital Sign Monitoring.

Purpose This study investigates the feasibility and potential utility of head-mounted displays for real-time wireless vital sign monitoring during surgical procedures. Methods In this randomized controlled pilot study, surgery residents (n = 14) performed simulated bedside procedures with traditional vital sign monitors and were randomized to addition of vital sign streaming to Google Glass. Time to recognition of preprogrammed vital sign deterioration and frequency of traditional monitor use was recorded. User feedback was collected by electronic survey. Results The experimental group spent 90% less time looking away from the procedural field to view traditional monitors during bronchoscopy (P = .003), and recognized critical desaturation 8.8 seconds earlier; the experimental group spent 71% (P = .01) less time looking away from the procedural field during thoracostomy, and recognized hypotension 10.5 seconds earlier. Trends toward earlier recognition of deterioration did not reach statistical significance. The majority of participants agreed that Google Glass increases situational awareness (64%), is helpful in monitoring vitals (86%), is easy to use (93%), and has potential to improve patient safety (85%). Conclusion In this early feasibility study, use of streaming to Google Glass significantly decreased time looking away from procedural fields and resulted in a nonsignificant trend toward earlier recognition of vital sign deterioration. Vital sign streaming with Google Glass or similar platforms is feasible and may enhance procedural situational awareness.