Regional cerebral saturation monitoring with near-infrared spectroscopy during selective antegrade cerebral perfusion: Diagnostic performance and relationship to postoperative stroke

ObjectiveTo investigate whether regional cerebral tissue oxygen saturation monitoring during hypothermic selective antegrade cerebral perfusion in surgery involving the aortic arch can predict neurologic sequelae and to evaluate the diagnostic performance of near-infrared spectroscopy monitoring in this setting.MethodsData from 46 consecutive patients were analyzed. Selective antegrade cerebral perfusion was established by perfusion of the right subclavian artery (with or without left carotid artery perfusion) or by separate concomitant perfusion of the innominate and the left carotid arteries. The bilateral regional cerebral tissue oxygen saturation index was monitored by using near-infrared spectroscopy equipment (INVOS 4100). Stroke was the primary clinical end point, along with the indices of diagnostic performance.ResultsSix patients died in the hospital, and 6 patients (13%) experienced a perioperative stroke. In patients with stroke, regional cerebral tissue oxygen saturation values were significantly lower during selective antegrade cerebral perfusion, and regional cerebral tissue oxygen saturation tended to be lower in the affected hemisphere. In receiver operating characteristic curve analysis, the area under the curve for relative regional cerebral tissue oxygen saturation values ranged from 0.72 to 0.87. During selective antegrade cerebral perfusion, regional cerebral tissue oxygen saturation between 76% and 86% of baseline had a sensitivity up to 83% and a specificity up to 94% in identifying individuals with stroke. The associated odds ratio for stroke was 5.6 (95% confidence interval, 0.5-144) to 21 (95% confidence interval, 1.8-566).ConclusionsMonitoring of regional cerebral tissue oxygen saturation by using near-infrared spectroscopy during selective antegrade cerebral perfusion allows detection of clinically important cerebral desaturation. It can help predict perioperative neurologic sequelae. Its performance as a diagnostic instrument is satisfying and supports its use as a noninvasive trend monitor of cerebral saturation

Coagulation, fibrinolysis, and cell activation in patients and shed mediastinal blood during coronary artery bypass grafting with a new heparin-coated surface

AbstractObjectives: Heparin coating of the cardiopulmonary bypass circuit is shown to improve the biocompatibility of the surface. We have studied a new heparin surface, the Corline Heparin Surface, applied to a complete set of an extracorporeal device used during coronary artery bypass grafting in terms of activation of inflammation, coagulation, and fibrinolysis in patients and in shed mediastinal blood. Methods: Sixty patients scheduled for coronary artery bypass grafting were randomized to one of 3 groups with heparin-coated devices receiving either a standard, high, or low dose of systemic heparin or to an uncoated but otherwise identical circuit receiving a standard dose of systemic heparin. Samples were drawn before, during, and after the operation from the pericardial cavity and in shed mediastinal blood. No autotransfusion of shed mediastinal blood was performed. Results: The Corline Heparin Surface significantly reduced the activation of coagulation, fibrinolysis, platelets, and inflammation compared with that seen with the uncoated surface in combination with a standard dose of systemic heparin during cardiac surgery with cardiopulmonary bypass. Both a decrease and an increase of systemic heparin in combination with the coated heparin surface resulted in higher activation of these processes. A significantly higher expression of all studied parameters was found in the shed mediastinal blood compared with in systemic blood at the same time. Conclusions: The Corline Heparin Surface used in cardiopulmonary bypass proved to be more biocompatible than an uncoated surface when using a standard systemic heparin dose. The low dose of systemic heparin might not be sufficient to maintain the antithrombotic activity, and the high dose resulted in direct cell activation rather than a further anti-inflammatory and anticoagulatory effect.J Thorac Cardiovasc Surg 2002;124:321-3

Aortic rupture after spinal correction for scoliosis in the presence of a thoracic stent graft

Corrective surgery for scoliosis often results in a lengthening of the spinal column and relative change of the position of the adjacent anatomical structures such as the aorta. The extent of these anatomical changes could be affected by the presence of a rigid aortic stent graft in the descending thoracic aorta. We present a case of aortic rupture after spinal correction for scoliosis in a 56-year-old female with a thoracic aortic stent graft. Extensive elongation of the aorta with concentration of the stress forces at the lower margin of the stent graft resulted in a weakening of the aortic wall and subsequent rupture

Quorum Sensing Regulation of the Two hcp Alleles in Vibrio cholerae O1 Strains

BACKGROUND: The type VI secretion system (T6SS) has emerged as a protein secretion system important to several gram-negative bacterial species. One of the common components of the system is Hcp, initially described as a hemolysin co-regulated protein in a serotype O17 strain of Vibrio cholerae. Homologs to V. cholerae hcp genes have been found in all characterized type VI secretion systems and they are present also in the serotype O1 strains of V. cholerae that are the cause of cholera diseases but seemed to have non-functional T6SS. METHODOLOGY/PRINCIPAL FINDINGS: The serotype O1 V. cholerae strain A1552 was shown to express detectable levels of Hcp as determined by immunoblot analyses using polyclonal anti-Hcp antiserum. We found that the expression of Hcp was growth phase dependent. The levels of Hcp in quorum sensing deficient mutants of V. cholerae were compared with the levels in wild type V. cholerae O1 strain A1552. The expression of Hcp was positively and negatively regulated by the quorum sensing regulators HapR and LuxO, respectively. In addition, we observed that expression of Hcp was dependent on the cAMP-CRP global transcriptional regulatory complex and required the RpoN sigma factor. CONCLUSION/SIGNIFICANCE: Our results show that serotype O1 strains of V. cholerae do express Hcp which is regarded as one of the important T6SS components and is one of the secreted substrates in non-O1 non-O139 V. cholerae isolates. We found that expression of Hcp was strictly regulated by the quorum sensing system in the V. cholerae O1 strain. In addition, the expression of Hcp required the alternative sigma factor RpoN and the cAMP-CRP global regulatory complex. Interestingly, the environmental isolates of V. cholerae O1 strains that showed higher levels of the HapR quorum sensing regulator in comparison with our laboratory standard serotype O1 strain A1552 where also expressing higher levels of Hcp

Long-term clinical outcomes after coronary artery bypass grafting with pedicled saphenous vein grafts

BACKGROUND: Coronary artery bypass grafting (CABG) using saphenous vein grafts (SVG) is vitiated by poor long-term patency of the vein grafts. Pedicled SVG harvested with the "no-touch" (NT) technique have demonstrated improved patency and could confer better outcomes. We aim to compare long-term results after CABG where NT or conventional technique was used for vein graft harvesting in a hypothesis-generating registry-based study. METHODS: Two propensity score matched cohorts (1349 patients) undergoing CABG with veins harvested with NT (NTT) or conventional (CT) technique in Sweden over the period 2005-2015 were used to compare long-term outcomes. Mortality, postoperative incidence of coronary angiography and need for reintervention was recorded and multivariable hazard ratios adjusted for risk factors were calculated. RESULTS: The mean follow-up time (SD) was 6.8 (3.3) years for NTT and 6.6 (3.2) years for CT. The adjusted hazard ratios for death, first angiography and need for reintervention for NTT patients were (95% CI) 0.97 (0.80-1.19), 0.76 (0.63-0.93), 0.91 (0.78-1.05), and 0.91 (0.71-1.17), respectively. Failed grafts were found in 43.2% of NTT patients and 53.6% of CT patients at angiography. CONCLUSIONS: In this study NT grafting was associated with a lower risk for repeat angiography, however no difference could be observed for mortality and need for reintervention. The earlier reported improvements in patency of NT veins could possibly be reflected in an improved clinical outcome during the first 10 years after surgery

Indirect Tire Monitoring System - Machine Learning Approach

The heavy vehicle industry has today no requirement to provide a tire pressure monitoring system by law. This has created issues surrounding unknown tire pressure and thread depth during active service. There is also no standardization for these kind of systems which means that different manufacturers and third party solutions work after their own principles and it can be hard to know what works for a given vehicle type. The objective is to create an indirect tire monitoring system that can generalize a method that detect both incorrect tire pressure and thread depth for different type of vehicles within a fleet without the need for additional physical sensors or vehicle specific parameters. The existing sensors that are connected communicate through CAN and are interpreted by the Drivec Bridge hardware that exist in the fleet. By using supervised machine learning a classifier was created for each axle where the main focus was the front axle which had the most issues. The classifier will classify the vehicles tires condition and will be implemented in Drivecs cloud service where it will receive its data. The resulting classifier is a random forest implemented in Python. The result from the front axle with a data set consisting of 9767 samples of buses with correct tire condition and 1909 samples of buses with incorrect tire condition it has an accuracy of 90.54% (0.96%). The data sets are created from 34 unique measurements from buses between January and May 2017. This classifier has been exported and is used inside a Node.js module created for Drivecs cloud service which is the result of the whole implementation. The developed solution is called Indirect Tire Monitoring System (ITMS) and is seen as a process. This process will predict bad classes in the cloud which will lead to warnings. The warnings are defined as incidents. They contain only the information needed and the bandwidth of the incidents are also controlled so incidents are created within an acceptable range over a period of time. These incidents will be notified through the cloud for the operator to analyze for upcoming maintenance decisions. © 2017 Published under licence by IOP Publishing Ltd

Clinical Outcomes After Surgical Revascularization Using No-Touch Versus Conventional Saphenous Vein Grafts : Mid-Term Follow-Up of Propensity Score Matched Cohorts

Previous studies have demonstrated superior patency of no-touch as compared to conventional saphenous vein grafts in coronary artery bypass grafting. We aimed to compare mid-term clinical outcomes of both techniques in a large cohort of routine patients. We identified all patients undergoing nonemergent primary coronary artery bypass grafting with either no-touch or conventional saphenous vein grafts at our institution between 2000 and 2020. Propensity score matching was used to create adjusted cohorts based on 5288 eligible patients. The primary outcome was the combined endpoint of all-cause mortality and repeat revascularization. Secondary outcomes were individual rates of all-cause mortality and repeat revascularization, surgical complications, and short-term mortality. Propensity score matching resulted in cohorts of no-touch (n = 923) and conventional (n = 923) saphenous vein grafted patients with comparable baseline characteristics. Mean follow-up time was significantly shorter for the no-touch compared to the conventional cohort (4.9 ± 2.3 vs 8.3 ± 2.6 years, P < 0.001). Up to 7-year follow-up, neither the rate of the primary composite endpoint nor death differed significantly between the cohorts. The rate of repeat revascularization was significantly higher in patients in the no-touch cohort (12.9% vs 9.3% at 7-year follow-up, P = 0.022. Post-hoc analysis of percutaneous coronary intervention during follow-up revealed comparable rates of saphenous vein graft failure (no-touch 42/923 (4.6%) vs conventional 32/923 (3.5%), P = 0.286). In this large propensity score matched registry study, coronary artery bypass with no-touch compared to conventional saphenous vein grafting did neither enhance mid-term survival nor reduce the rate of repeat revascularization

Application of cryoenergy to improve septal exposure during transaortic septal myectomy in hypertrophic obstructive cardiomyopathy

For the past few decades, the transaortic septal myectomy (Morrow's procedure) has been the gold standard for treating severe left ventricular outflow tract obstruction in hypertrophic obstructive cardiomyopathy (HOCM) patients. 30-day mortality has been reported at less than 1% in dedicated centers. However, in a subgroup of patients, the interventricular septal obstruction is localized very distally, below the aortic valve plane, and the transaortic approach can be very challenging. A subset of these patients can present with residual obstruction after surgery, due to inadequate length of septal excision, leading to reoperation. The aim of this work is to illustrate an original application of cryoenergy to improve the transaortic exposure of the interventricular septum and thus enable surgeons to perform very distal myectomies in HOCM patients