51 research outputs found

    Hierarchical Traffic Management of Multi-AGV Systems With Deadlock Prevention Applied to Industrial Environments

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    This paper concerns the coordination and the traffic management of a group of Automated Guided Vehicles (AGVs) moving in a real industrial scenario, such as an automated factory or warehouse. The proposed methodology is based on a three-layer control architecture, which is described as follows: 1) the Top Layer (or Topological Layer) allows to model the traffic of vehicles among the different areas of the environment; 2) the Middle Layer allows the path planner to compute a traffic sensitive path for each vehicle; 3) the Bottom Layer (or Roadmap Layer) defines the final routes to be followed by each vehicle and coordinates the AGVs over time. In the paper we describe the coordination strategy we propose, which is executed once the routes are computed and has the aim to prevent congestions, collisions and deadlocks. The coordination algorithm exploits a novel deadlock prevention approach based on time-expanded graphs. Moreover, the presented control architecture aims at grounding theoretical methods to an industrial application by facing the typical practical issues such as graphs difficulties (load/unload locations, weak connections,), a predefined roadmap (constrained by the plant layout), vehicles errors, dynamical obstacles, etc. In this paper we propose a flexible and robust methodology for multi-AGVs traffic-aware management. Moreover, we propose a coordination algorithm, which does not rely on ad hoc assumptions or rules, to prevent collisions and deadlocks and to deal with delays or vehicle motion errors. Note to Practitioners-This paper concerns the coordination and the traffic management of a group of Automated Guided Vehicles (AGVs) moving in a real industrial scenario, such as an automated factory or warehouse. The proposed methodology is based on a three-layer control architecture, which is described as follows: 1) the Top Layer (or Topological Layer) allows to model the traffic of vehicles among the different areas of the environment; 2) the Middle Layer allows the path planner to compute a traffic sensitive path for each vehicle; 3) the Bottom Layer (or Roadmap Layer) defines the final routes to be followed by each vehicle and coordinates the AGVs over time. In the paper we describe the coordination strategy we propose, which is executed once the routes are computed and has the aim to prevent congestions, collisions and deadlocks. The coordination algorithm exploits a novel deadlock prevention approach based on time-expanded graphs. Moreover, the presented control architecture aims at grounding theoretical methods to an industrial application by facing the typical practical issues such as graphs difficulties (load/unload locations, weak connections, ), a predefined roadmap (constrained by the plant layout), vehicles errors, dynamical obstacles, etc. In this paper we propose a flexible and robust methodology for multi-AGVs traffic-aware management. Moreover, we propose a coordination algorithm, which does not rely on ad hoc assumptions or rules, to prevent collisions and deadlocks and to deal with delays or vehicle motion errors

    Adjunctive therapy with vitamin c and thiamine in patients treated with steroids for refractory septic shock: A propensity matched before-after, case-control study

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    Purpose: Triple therapy with steroids, vitamin C and thiamine has been recently proposed as a safe and beneficial in patients with sepsis. In 2017, we added the use of intravenous vitamin C and thiamine in septic shock patients receiving low dose hydrocortisone because poorly responsive to vasopressors. Aim of this study is to verify whether triple therapy rather than steroids alone can improve outcome in patients with refractory shock. Materials and methods: In this before-after retrospective analysis, we compared septic shock patients admitted to our intensive care unit (ICU) who received triple therapy from June 2017 to November 2019 to septic shock patients who received only hydrocortisone from January 2015 to June 2017. Patients of the two study periods were matched 1:1 using a propensity score model. Results: A final cohort of 56 patients treated with triple therapy were matched to 56 patients treated only with steroids. Triple therapy reduced the length of mechanical ventilation (p = 0,01) and showed a trend in lowering the 30-day and hospital mortality compared to therapy with only hydrocortisone. Conclusions: Although with significant limitations, our experience indicated that triple therapy seems to provide an improvement of clinical outcomes in patients with refractory septic shock

    Guide-wire replacement of a mini-midline catheter with a central venous catheter: A retrospective study on 63 cases

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    Background: Achieving a reliable venous access in a particular subset of patients and/or in emergency settings can be challenging and time-consuming. Furthermore, many hospitalized patients do not meet the criteria for central venous catheter positioning, unless an upgrade of the treatment is further needed. The mini-midline catheter has already showed to be reliable and safe as a stand-alone device, since it is easily and rapidly inserted and can indwell up to 1 month. Methods: In this further case series, we retrospectively evaluated data from 63 patients where a previously inserted mini-midline catheter was upgraded to a central venous catheter (the devices inserted in the arm replaced by peripherally inserted central catheter and others inserted “off-label” in the internal jugular replaced by single lumen centrally inserted central catheter), being used as introducer for the Seldinger guidewire. Results: The guidewire replacement was been made even early (after 1 day) or late (more than 10 days), usually following a need for an upgrade in treatment. No early or late complications were reported. Conclusion: According to the preliminary data we collected, this converting procedure seems to be feasible and risk-free, since neither infectious nor thrombotic complications were reported

    Randomised controlled trial comparing efficacy and safety of high versus low Low-Molecular Weight Heparin dosages in hospitalized patients with severe COVID-19 pneumonia and coagulopathy not requiring invasive mechanical ventilation (COVID-19 HD): a structured summary of a study protocol.

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    To assess whether high doses of Low Molecular Weight Heparin (LMWH) (i.e. Enoxaparin 70 IU/kg twice daily) compared to standard prophylactic dose (i.e., Enoxaparin 4000 IU once day), in hospitalized patients with COVID19 not requiring Invasive Mechanical Ventilation [IMV], are: a)more effective in preventing clinical worsening, defined as the occurrence of at least one of the following events, whichever comes first: 1.Death2.Acute Myocardial Infarction [AMI]3.Objectively confirmed, symptomatic arterial or venous thromboembolism [TE]4.Need of either: a.Continuous Positive Airway Pressure (Cpap) or Non-Invasive Ventilation (NIV) orb.IMV in patients who at randomisation were receiving standard oxygen therapy5.IMV in patients who at randomisation were receiving non-invasive mechanical ventilationb)Similar in terms of major bleeding risk TRIAL DESIGN: Multicentre, randomised controlled, superiority, open label, parallel group, two arms (1:1 ratio), in-hospital study

    Marked T cell activation, senescence, exhaustion and skewing towards TH17 in patients with Covid-19 pneumonia.

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    We provide an in-depth investigation of the T cell compartment and functionality, cytokine production and plasma levels in a total of 39 patients affected by Covid-19 pneumonia. At admission, patients were lymphopenic; for all, SARS-CoV-2 was detected in a nasopharyngeal swab specimen by real-time RT-PCR, and pneumonia was subsequently confirmed by X-rays. Detailed 18-parameter flow cytometry coupled with unsupervised data analysis revealed that patients showed similar percentages of CD4+ and CD8+ T cells, but a decreased absolute number in both populations. For CD4+ T lymphocytes, we found a significant decrease in the number of na\uefve, central and effector memory cells and an increased percentage of terminally differentiated cells, regulatory T cells, and of those that were activated or that were expressing PD1 and CD57 markers. Studies on chemokine receptors and lineage-specifying transcription factors revealed that, among CD4+ T cells, patients displayed a lower percentage of cells expressing CCR6 or CXCR3, and of those co-expressing CCR6 and CD161, but higher percentages of 62 CXCR4+ or CCR4+ cells. No differences were noted in the expression of T-bet or GATA-3. Analyses of patients' CD8+ T cells showed decreased numbers of na\uefve and central memory and increased amounts of activated cells, accompanied by increased percentages of activated cells and of lymphocytes expressing CD57, PD1, or both. CD8+ T cells expressed lower percentages of CCR6+, CXCR3+ or T-bet+ cells and of CXCR3+,T-bet+ or CCR6+,CD161+ lymphocytes. We also found higher percentages of cells expressing CCR4+, CXCR4 or GATA-3. Analyses of lymphocyte proliferation revealed that terminally differentiated CD4+ and CD8+ T cell from patients had a lower proliferative index than controls, whereas cellular bioenergetics, measured by the quantification of mitochondrial oxygen consumption and extracellular acidification rate, was similar in CD4+ T cells from both groups. We measured plasma level of 31 cytokines linked to inflammation, including T helper (TH)type-1 and TH2 cytokines, chemokines, galectins, pro- and anti-inflammatory mediators, finding that most were dramatically increased in Covid-19 patients, confirming the presence of a massive cytokine storm. Analysis of the production of different cytokines after stimulation by anti-CD3/CD28 monoclonal antibodies revealed that patients not only had a high capacity to produce tumour necrosis factor (TNF)-\u3b1, interferon (IFN)-\u3b3 and interleukin (IL)-2, but also showed a significant skewing of CD4+ T cells towards the TH17 phenotype. A therapeutic approach now exists based on the administration of drugs that block IL-6pathway, and seems to improve the disease. IL-17 is crucial in recruiting and activating neutrophils, cells that can migrate to the lung and are heavily involved in the pathogenesis of Covid-19. We show here that a skewing of activated T cells towards the TH17 functional phenotype exists in Covid-19 patients. We therefore suggest that blocking the IL-17 pathway by biological drugs that are already used to treat different pathologies could provide a novel, additional strategy to improve the health of patients infected by SARS-CoV-2

    Development and validation of a prediction model for tocilizumab failure in hospitalized patients with SARS-CoV-2 infection

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    Background The aim of this secondary analysis of the TESEO cohort is to identify, early in the course of treatment with tocilizumab, factors associated with the risk of progressing to mechanical ventilation and death and develop a risk score to estimate the risk of this outcome according to patients' profile. Methods Patients with COVID-19 severe pneumonia receiving standard of care + tocilizumab who were alive and free from mechanical ventilation at day 6 after treatment initiation were included in this retrospective, multicenter cohort study. Multivariable logistic regression models were built to identify predictors of mechanical ventilation or death by day-28 from treatment initiation and β-coefficients were used to develop a risk score. Secondary outcome was mortality. Patients with the same inclusion criteria as the derivation cohort from 3 independent hospitals were used as validation cohort. Results 266 patients treated with tocilizumab were included. By day 28 of hospital follow-up post treatment initiation, 40 (15%) underwent mechanical ventilation or died [26 (10%)]. At multivariable analysis, sex, day-4 PaO2/FiO2 ratio, platelets and CRP were independently associated with the risk of developing the study outcomes and were used to generate the proposed risk score. The accuracy of the score in AUC was 0.80 and 0.70 in internal validation and test for the composite endpoint and 0.92 and 0.69 for death, respectively. Conclusions Our score could assist clinicians in identifying, early after tocilizumab administration, patients who are likely to progress to mechanical ventilation or death, so that they could be selected for eventual rescue therapies

    Better prognosis in females with severe COVID-19 pneumonia: possible role of inflammation as potential mediator.

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    Objectives: Sex differences in COVID-19 severity and mortality have been described. Key aims of this analysis were to compare the risk of invasive mechanical ventilation (IMV) and mortality by sex and to explore whether variation in specific biomarkers could mediate this difference. Methods: This was a retrospective, observational cohort study among patients with severe COVID- 19 pneumonia. A survival analysis was conducted to compare time to the composite endpoint of IMV or death by sex. Interaction was formally tested to compare the risk difference by sex in subsets. Mediation analysis with a binary endpoint IMV or death (yes/no) by end of follow-up for a number of inflammation/coagulation biomarkers in the context of counterfactual prediction was also conducted. Results: Among 415 patients, 134 were females (32%) and 281 males (67%), median age 66 years (IQR 54-77). At admission, females showed a significantly less severe clinical and respiratory profiles with a higher PaO2/FiO2 (254 mmHg vs 191 mmHg; p=0.023). By 28 days from admission, 49.2% (95% CI: 39.6-58.9%) of males vs. 31.7% (17.9-45.4%) of females underwent IMV or death (log-rank pvalue<0.0001) and this amounted to a difference in HR of 0.40 (0.26-0.63, p=0.0001). The AUC in Creactive protein (CRP) over the study period appeared to explain 85% of this difference in risk by sex. Conclusions: Our analysis confirms a difference in the risk of COVID-19 clinical progression by sex and provides a hypothesis for potential mechanisms leading to this. CRP showed a predominant role to mediate the difference in risk by sex

    L’utilizzo del Lat Gel nell’anestesia locale delle ferite pediatriche in Pronto Soccorso

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    Sedation and analgesia are common strategies to manage acute procedural pain and anxiety in Emergency Department, but no standardized protocol in children is approved. Application of topical LATgel (Lidocaine 4%, Adrenaline 0,05%, Tetracaine 0,5%) on wounds before painful procedures seems to be as effective as intradermal infiltrations in reducing procedural pain. A review of 34 paediatric cases from Pavullo Hospital (MO, Italy) presenting with laceration requiring suture was conducted. Pain assessment was performed in triage and, after 30mins of LATgel application, from parents, children and doctors during the suture. LATgel administration improves children’s compliance, minimizing pain and related fear during procedures. Our findings are consistent with international literature

    Tocilizumab in patients with severe COVID-19: a retrospective cohort study

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    Background: No therapy is approved for COVID-19 pneumonia. The aim of this study was to assess the role of tocilizumab in reducing the risk of invasive mechanical ventilation and death in patients with severe COVID-19 pneumonia who received standard of care treatment. Methods: This retrospective, observational cohort study included adults ( 6518 years) with severe COVID-19 pneumonia who were admitted to tertiary care centres in Bologna and Reggio Emilia, Italy, between Feb 21 and March 24, 2020, and a tertiary care centre in Modena, Italy, between Feb 21 and April 30, 2020. All patients were treated with the standard of care (ie, supplemental oxygen, hydroxychloroquine, azithromycin, antiretrovirals, and low molecular weight heparin), and a non-randomly selected subset of patients also received tocilizumab. Tocilizumab was given either intravenously at 8 mg/kg bodyweight (up to a maximum of 800 mg) in two infusions, 12 h apart, or subcutaneously at 162 mg administered in two simultaneous doses, one in each thigh (ie, 324 mg in total), when the intravenous formulation was unavailable. The primary endpoint was a composite of invasive mechanical ventilation or death. Treatment groups were compared using Kaplan-Meier curves and Cox regression analysis after adjusting for sex, age, recruiting centre, duration of symptoms, and baseline Sequential Organ Failure Assessment (SOFA) score. Findings: Of 1351 patients admitted, 544 (40%) had severe COVID-19 pneumonia and were included in the study. 57 (16%) of 365 patients in the standard care group needed mechanical ventilation, compared with 33 (18%) of 179 patients treated with tocilizumab (p=0\ub741; 16 [18%] of 88 patients treated intravenously and 17 [19%] of 91 patients treated subcutaneously). 73 (20%) patients in the standard care group died, compared with 13 (7%; p<0\ub70001) patients treated with tocilizumab (six [7%] treated intravenously and seven [8%] treated subcutaneously). After adjustment for sex, age, recruiting centre, duration of symptoms, and SOFA score, tocilizumab treatment was associated with a reduced risk of invasive mechanical ventilation or death (adjusted hazard ratio 0\ub761, 95% CI 0\ub740\u20130\ub792; p=0\ub7020). 24 (13%) of 179 patients treated with tocilizumab were diagnosed with new infections, versus 14 (4%) of 365 patients treated with standard of care alone (p<0\ub70001). Interpretation: Treatment with tocilizumab, whether administered intravenously or subcutaneously, might reduce the risk of invasive mechanical ventilation or death in patients with severe COVID-19 pneumonia. Funding: None
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