4,835 research outputs found

    Prediction of postoperative liver regeneration from clinical information using a data-led mathematical model

    No full text
    Although the capacity of the liver to recover its size after resection has enabled extensive liver resection, post-hepatectomy liver failure remains one of the most lethal complications of liver resection. Therefore, it is clinically important to discover reliable predictive factors after resection. In this study, we established a novel mathematical framework which described post-hepatectomy liver regeneration in each patient by incorporating quantitative clinical data. Using the model fitting to the liver volumes in series of computed tomography of 123 patients, we estimated liver regeneration rates. From the estimation, we found patients were divided into two groups: i) patients restored the liver to its original size (Group 1, n?=?99); and ii) patients experienced a significant reduction in size (Group 2, n?=?24). From discriminant analysis in 103 patients with full clinical variables, the prognosis of patients in terms of liver recovery was successfully predicted in 85–90% of patients. We further validated the accuracy of our model prediction using a validation cohort (prediction?=?84–87%, n?=?39). Our interdisciplinary approach provides qualitative and quantitative insights into the dynamics of liver regeneration. A key strength is to provide better prediction in patients who had been judged as acceptable for resection by current pragmatic criteria

    Olfactory groove meningioma: report of 99 cases surgically treated at the Catholic University School of Medicine, Rome

    Get PDF
    OBJECTIVE: We reviewed our series of olfactory groove meningiomas (OGMs) with the aim to relate the surgical approach with outcome and to define clinical and pathologic predictors of prognosis. METHODS: Ninety-nine patients who underwent 113 craniotomies at our Institution between 1984 and 2010 were entered this study. The relationship between surgical approach (bifrontal, fronto-orbito-basal, and pterional) and either tumor diameter, extent of tumor resection, complication rate, need of reoperation, and Karnofsky Performance Status (KPS) was analyzed. The impact of age ( 64 70 vs. > 70 years), sex, tumor diameter (< 6 vs. 65 6 cm), pre- and postoperative KPS (< 80 vs. 65 80), Simpson grade (I-II vs. III-IV), and World Health Organization (WHO) histologic grade (I vs. II-III) on survival was assessed. Kaplan-Meier survival curves were plotted and differences in survival between groups of patients were compared. A multivariate analysis adjusted for age, pre- and postoperative KPS, Simpson grade, tumor diameter, and WHO histologic grade also was performed. RESULTS: The fronto-orbito-basal approach (n = 22) allowed a significantly greater percentage of Simpson I-II removals than the bifrontal (n = 70) and pterional approach (n = 21) (P = 0.0354 and P = 0.0485, respectively). The risk of life-threatening complications trended to be lower in patients operated upon either via the fronto-orbito-basal and via the pterional approach than in those treated via the bifrontal approach. Retraction-related brain swelling did not occur in any case after the fronto-orbito-basal approach (P = 0.0384); however, this approach was associated with a greater rate of cerebrospinal fluid leak (P = 0.0011). Among prognostic factors, age 64 70 years (P = 0.0044), tumor diameter <6 cm (P = 0.0455), pre- and postoperative KPS 65 80 (both P < 0.0001), Simpson grade I-II (P = 0.0096), and WHO histologic grade I (P = 0.0112) were significantly associated with longer overall survival. Age (P = 0.0393) and WHO histologic grade (P = 0.0418) emerged as independent prognostic factors for overall survival on multivariate analysis. CONCLUSION: In the largest series of OGMs published to date, the bifrontal approach was associated with a greater risk of life-threatening complications compared with the lateral pterional and fronto-orbito-basal approaches. The fronto-orbito-basal approach provided greater chances of total tumor removal than the bifrontal and pterional approaches. Two independent factors for overall survival of patients with OGM were identified, namely age and WHO grade

    Characterization of Postoperative Recovery After Cardiac Surgery- Insights into Predicting Individualized Recovery Pattern

    Get PDF
    Understanding the patterns of postoperative recovery after cardiac surgery is important from several perspectives: to facilitate patient-centered treatment decision making, to inform health care policy targeted to improve postoperative recovery, and to guide patient care after cardiac surgery. Our works aimed to address the following: 1) to summarize existing approaches to measuring and reporting postoperative recovery after cardiac surgery, 2) to develop a framework to efficiently measure patient-reported outcome measures to understand longitudinal recovery process, and 3) to explore ways to summarize the longitudinal recovery data in an actionable way, and 4) to evaluate whether addition of patient information generated through different phases of care would improve the ability to predict patient’s outcome. We first conducted a systematic review of the studies reporting on postoperative recovery after cardiac surgery using patient-reported outcome measures. Our systematic review demonstrated that the current approaches to measuring and reporting recovery as a treatment outcome varied widely across studies. This made synthesis of collective knowledge challenging and highlighted key gaps in knowledge, which we sought to address in our prospective cohort study. We conducted a prospective single-center cohort study of patients after cardiac surgery to measure their recovery trajectory across multiple domains of recovery. Using a digital platform, we measured patient recovery in various domains over 30 days after surgery to visualize a granular evolution of patient recovery after cardiac surgery. We used a latent class analysis to facilitate identification of dominant trajectory patterns that had been obscured in a conventional way of reporting such time-series data using group-level means. For the pain domain, we identified 4 trajectory classes, one of which was a group of patients with persistently high pain trajectory that only became distinguishable from less concerning group after 10 days. Therefore, we obtained a potentially actionable insights to tailoring individualized follow-up timing after surgery to improve the pain control. The prospective study embodied several important features to successfully conducting such studies of patient-reported outcomes. This included the use of digital platform to facilitate efficient data collection extending after hospital discharge, iteratively improving the protocol to optimize patient engagement including evaluation of potential barriers to survey completion, and using latent class analysis to identify dominant patterns of recovery trajectories. We outlined these insights in the protocol manuscript to inform subsequent studies aiming to leverage such a digital platform to measure longitudinal patient-centered outcome. Finally, we evaluated the potential value of incorporating health care data generated in the different phases of patient care in improving the prediction of postoperative outcomes after cardiac surgery. The current standard of risk prediction in cardiac surgery is the Society of Thoracic Surgeons’ (STS) risk model, which only uses patient information available preoperatively. We demonstrated through prediction models fitted on the national STS risk model for coronary artery bypass graft surgery that the addition of intraoperative variables to the conventional preoperative variable set improved the performance of prediction models substantially. Using machine learning approach to such a high-dimensional dataset proved to be marginally important. This work demonstrated the potential value and importance of being able to leverage health care data to continuously update the prediction to inform patient outcomes and guide clinical care. Our work collectively advanced knowledge in several key aspects of postoperative recovery. First, we highlighted the knowledge gap in the existing literature through characterizing the variability in the ways such studies had been conducted. Second, we designed and described a framework to measure postoperative recovery and an analytical approach to informatively characterize longitudinal patient recovery. Third, we employed these designs in a prospective cohort study to measure and analyze recovery trajectories and described clinical insights obtained from the study. Finally, we demonstrated the potential value of a dynamic risk model to iteratively improve its predictive performance by incorporating new data generated as the patient progresses through the phase of care. Such a platform has the potential to individualize patient’s post-acute care in a data-driven manner

    Comparative Effectiveness of Stereo-EEG versus Subdural Grids in Epilepsy Surgery

    Get PDF
    OBJECTIVE: To compare the outcomes of subdural electrode (SDE) implantations versus stereo-electroencephalography (SEEG), the two predominant methods of intracranial EEG (iEEG) performed in difficult to localize drug-resistant focal epilepsy. METHODS: The Surgical Therapies Commission of the International League Against Epilepsy created an international registry of iEEG patients implanted between 2005-2019 with ≥ 1 year follow-up. We used propensity score matching to control exposure selection bias and generate comparable cohorts. Study endpoints: 1) likelihood of resection after iEEG; 2) seizure-freedom at last follow-up; and 3) complications (composite of either post-operative infection, symptomatic intracranial hemorrhage, or permanent neurologic deficit). RESULTS: Ten study sites from seven countries and three continents contributed 2,012 patients, including 1,468 (73%) eligible for analysis (526 SDE, 942 SEEG) of whom 988 (67%) underwent subsequent resection. Propensity score matching improved covariate balance between exposure groups for all analyses. Propensity-matched patients who underwent SDE had higher odds of subsequent resective surgery (odds ratio OR = 1.4, 95% CI 1.05 - 1.84), and higher odds of complications (OR=2.24, 95% CI 1.34-3.74; unadjusted: 9.6% after SDE vs. 3.3% after SEEG). Odds of seizure-freedom in propensity-matched resected patients were 1.66 times higher (95% CI 1.21, 2.26) for SEEG compared to SDE (unadjusted: 55% seizure-free after SEEG-guided resections vs. 41% after SDE) INTERPRETATION: Compared to SEEG, SDE evaluations are more likely to lead to brain surgery in patients with drug-resistant epilepsy, but have more surgical complications and lower probability of seizure-freedom. This comparative-effectiveness study provides the highest feasible evidence level to guide decisions on iEEG. This article is protected by copyright. All rights reserved

    Toward noninvasive assessment of flap viability with time-resolved diffuse optical tomography: a preclinical test on rats

    Get PDF
    The noninvasive assessment of flap viability in autologous reconstruction surgery is still an unmet clinical need. To cope with this problem, we developed a proof-of-principle fully automatized setup for fast time-gated diffuse optical tomography exploiting Mellin–Laplace transform to obtain three-dimensional tomographic reconstructions of oxy- and deoxy-hemoglobin concentrations. We applied this method to perform preclinical tests on rats inducing total venous occlusion in the cutaneous abdominal flaps. Notwithstanding the use of just four source-detector couples, we could detect a spatially localized increase of deoxyhemoglobin following the occlusion (up to 550 μM in 54 min). Such capability to image spatio-temporal evolution of blood perfusion is a key issue for the noninvasive monitoring of flap viability

    Advancing Patient Safety in the U.S. Department of Veterans Affairs

    Get PDF
    As part of a systemwide transformation, the VA formed its National Center for Patient Safety to foster an organizational culture of safety within its nationwide network of hospitals and outpatient clinics. A recent medical team training program designed to improve communication among operating room staff was associated with a reduction in surgical mortality and improvements in quality of care, on-time surgery starts, and staff morale. The program is now being expanded to other clinical units, along with a patient engagement program that prevents errors by facilitating communication relating to patients' daily care plans. A recognition program stimulated facilities to conduct timelier and higher-quality root-cause analyses of reported safety events to identify stronger actions for preventing their recurrence. Other initiatives have reduced rates of health care -- associated infections, patient mortality, and post-operative complications. Success factors include leadership accountability for performance and organizational support for testing, expanding, and adopting improvements

    BIOCONSTRUCTION IN TRAUMATOLOGY

    Get PDF
    In the pages of his book the author shares his experience of inventor and creator of the new system for the situated on bone stable - functional osteosynthesis "METOST". On the most parts of this system components the author received a patent for an invention. Over the past 20–30 years, the stable – functional osteosynthesis of long tubular bones is confidently taking the leading place, as well in our country as abroad. However, the fixatives that are used for this purpose are not ideal and need to be improved. Each step and every element of the METOST system has been subjected to comprehensive analysis, mechanical and mathematical modeling and testing on experimental animals. Only after that, the author started using METOST system in the clinic on patients and achieved excellent results, having operated over 1,500 patients and reducing the percentage of errors and complications to – 1.5 %. This work could be used as a handbook for master classes for creative doctors who have dedicated their efforts to improving the methods of patients treatment. The monograph could be useful for all operating traumatologists - orthopedists, as well experienced doctors, as young aimed to succes – inventors. Indexing:                     In the pages of his book the author shares his experience of inventor and creator of the new system for the situated on bone stable - functional osteosynthesis "METOST". On the most parts of this system components the author received a patent for an invention. Over the past 20–30 years, the stable – functional osteosynthesis of long tubular bones is confidently taking the leading place, as well in our country as abroad. However, the fixatives that are used for this purpose are not ideal and need to be improved. Each step and every element of the METOST system has been subjected to comprehensive analysis, mechanical and mathematical modeling and testing on experimental animals. Only after that, the author started using METOST system in the clinic on patients and achieved excellent results, having operated over 1,500 patients and reducing the percentage of errors and complications to – 1.5 %. This work could be used as a handbook for master classes for creative doctors who have dedicated their efforts to improving the methods of patients treatment. The monograph could be useful for all operating traumatologists - orthopedists, as well experienced doctors, as young aimed to succes – inventors. Indexing:                 &nbsp

    The association of anti-platelet factor 4/heparin antibodies with early and delayed thromboembolism after cardiac surgery

    Get PDF
    Heparin induced thrombocytopenia (HIT) is a prothrombotic response to heparin therapy with platelet activating, anti-PF4/heparin antibodies leading to thrombocytopenia associated with thromboembolism
    corecore