Using Peripheral Venous Pressure Waveforms to Predict Key Hemodynamic Parameters

Analysis of peripheral venous pressure (PVP) waveforms is a novel method of monitoring intravascular volume. Two cohorts were used to study the hemodynamics change of the body state and its influence on the PVP using (1) dehydration setting with infants suffering from pyloric stenosis and (2) hemorrhage setting during a craniosynostosis elective surgery. The goal of this research is to develop a minimally invasive method of analyzing the PVP waveforms and find correlations with volume loss. Twenty-three pyloric stenosis patients PVP were acquired at five stages and were divided into euvolemic, normal fluid volume, and hypovolemic, significant fluid loss. Seven craniosynostosis patients were enrolled and the PVP was acquired at the intervention to explore if the isoflurane dosage influences the PVP. A multivariate analysis of variances (MANOVA) was used to test if the PVP was influenced by the volume change and the anesthetic drugs effect. Prediction algorithms based on Fast Fourier Transform were utilized at the two cohort patients analyses to classify an arbitrary PVP into its correct classification. Our research found that PVP signal is influenced by the different hemodynamics states of the body. Based on MANOVA outcomes, we built prediction systems and they were able to categorize an arbitrary PVP signal into its correct classification. The k-nearest neighbor (k-NN) model correctly predicted 77% of the data in the euvolemic and hypovolemic groups. The k-NN models of the anesthetic drugs were able to correctly predict correctly at least 85% of the preoperative and intraoperative signals of the pyloric stenosis patients and the different isoflurane dosages of the craniosynostosis patients. Analyzing the PVP signal is a promising tool for measuring the dehydration level in acute settings. Our results imply that the subsequent changes in vascular resistance due to inhaled and infused anesthetics are reflected in the peripheral veins. A technology that would accurately assess the volume status of a patient to guide triage and treatment would be a significant improvement in various care settings. This minimally invasive technology utilizes a standard peripheral intravenous line and a commercial pressure-monitoring transducer, which exist today and requires no new clinical skills

Veterans in Crisis: Identifying and Reducing Suicide

The base of this Integrative Review is built on the foundation of information from research by Ramchand (2021), “Veterans are committing suicide at a rate twice the non-veteran.” (p.2) and “From 2005 to 2018 the suicide rate went from 20% to 32%” in the veteran population. (p.3). According to Ahmedani et al. (2019), “The majority of persons committing suicide (71.2%) had received health care in the 180 days prior to their death.” (p.6). This review analyzed and organized the findings to spotlight 4 common themes that lead to a better understanding of best practices. Eligibility criteria started with the PICOT question “In combat veterans, what role does untreated pain play in suicide rates?” The Preferred Reporting Items for Systematic Reviews and Meta-Analyses or PRISMA flow diagram was used to narrow the PubMed search results. The literature review focused directly on combat wounded veterans. The research links Post Traumatic Stress Disorder (PTSD) and chronic pain as a comorbidity that increases suicide risk. According to Chisholm-Burns et. al., (2019), “substantial evidence that pharmacists can make an impact through appropriate pain management.” (p.2) The goal of this review is to identify and reduce suicide in the veteran population

Attacking Shortest Paths by Cutting Edges

Identifying shortest paths between nodes in a network is a common graph analysis problem that is important for many applications involving routing of resources. An adversary that can manipulate the graph structure could alter traffic patterns to gain some benefit (e.g., make more money by directing traffic to a toll road). This paper presents the Force Path Cut problem, in which an adversary removes edges from a graph to make a particular path the shortest between its terminal nodes. We prove that this problem is APX-hard, but introduce PATHATTACK, a polynomial-time approximation algorithm that guarantees a solution within a logarithmic factor of the optimal value. In addition, we introduce the Force Edge Cut and Force Node Cut problems, in which the adversary targets a particular edge or node, respectively, rather than an entire path. We derive a nonconvex optimization formulation for these problems, and derive a heuristic algorithm that uses PATHATTACK as a subroutine. We demonstrate all of these algorithms on a diverse set of real and synthetic networks, illustrating the network types that benefit most from the proposed algorithms.Comment: 37 pages, 11 figures; Extended version of arXiv:2104.0376

GRASP: Accelerating Shortest Path Attacks via Graph Attention

Recent advances in machine learning (ML) have shown promise in aiding and accelerating classical combinatorial optimization algorithms. ML-based speed ups that aim to learn in an end to end manner (i.e., directly output the solution) tend to trade off run time with solution quality. Therefore, solutions that are able to accelerate existing solvers while maintaining their performance guarantees, are of great interest. We consider an APX-hard problem, where an adversary aims to attack shortest paths in a graph by removing the minimum number of edges. We propose the GRASP algorithm: Graph Attention Accelerated Shortest Path Attack, an ML aided optimization algorithm that achieves run times up to 10x faster, while maintaining the quality of solution generated. GRASP uses a graph attention network to identify a smaller subgraph containing the combinatorial solution, thus effectively reducing the input problem size. Additionally, we demonstrate how careful representation of the input graph, including node features that correlate well with the optimization task, can highlight important structure in the optimization solution

Defense Against Shortest Path Attacks

Identifying shortest paths between nodes in a network is an important task in applications involving routing of resources. Recent work has shown that a malicious actor can manipulate a graph to make traffic between two nodes of interest follow their target path. In this paper, we develop a defense against such attacks by modifying the weights of the graph that users observe. The defender must balance inhibiting the attacker against any negative effects of the defense on benign users. Specifically, the defender's goals are: (a) to recommend the shortest paths possible to users, (b) for the lengths of the shortest paths in the published graph to be close to those of the same paths in the true graph, and (c) to minimize the probability of an attack. We formulate the defense as a Stackelberg game in which the defender is the leader and the attacker is the follower. In this context, we also consider a zero-sum version of the game, in which the defender's goal is to minimize cost while achieving the minimum possible attack probability. We show that this problem is NP-hard and propose heuristic solutions based on increasing edge weights along target paths in both the zero-sum and non-zero-sum settings. Relaxing some constraints of the original problem, we formulate a linear program for local optimization around a feasible point. We present defense results with both synthetic and real network datasets and show that these methods often reach the lower bound of the defender's cost

Six-year follow-up of a pulmonary autograft in the mitral position: The Ross II procedure

AbstractJ Thorac Cardiovasc Surg 1999;117:614-

Oral thearubigins do not protect against acetaminopheninduced hepatotoxicity in mice

Purpose: To investigate the potential protective effect of oral repeated doses of thearubigins against acetaminophen-induced hepatotoxicity in mice.Methods: Mice were randomly divided into six groups (n=8) and administered the following: Control group (saline), acetaminophen group (saline), N-acetylcysteine group (500 mg/kg/day), and thearubigins groups (60, 70, 100 mg/kg/day). The drugs were given orally by gavage for seven days. On day 7, 1 h after the last dose of treatment, the mice (except control group) were given a single dose of acetaminophen (n-acetyl-p-aminophenol, APAP) orally by gavage (350 mg/kg) and then sacrificed 4 h post-APAP intake. Blood was collected for biochemical measurements and their liver were subjected to biochemical and histopathological assessment.Results: The acetaminophen group showed significant increases (p < 0.001) in serum alanine aminotransferase level, hepatic cytochrome P2E1 level, and serum and hepatic malondialdehyde levels. Moreover it showed significant decrease (p < 0.001) in serum and hepatic glutathione levels. Morphologically, the liver sections showed cellular necrosis, vacuolization, and degeneration around the centrilobular veins. Pretreatment with N-acetylcysteine reversed all acetaminophen-induced changes (p < 0.001 for all biomarkers except for hepatic MDA (p = 0.014) while pretreatment with thearubigins failed to reverse any of them.Conclusion: Oral repeated doses of thearubigins failed to protect against acetaminophen-induced hepatotoxicity in mice and didn't affect hepatic cytochrome P2E1 level.Keywords: Acetaminophen, Hepatotoxicity, Thearubigins, N-acetylcysteine, Cellular necrosis, Vacuolization, Hepatic cytochrome P2E

Hand hygiene knowledge and attitude of medical students in western Saudi Arabia

Background The practice of hand hygiene (HH) has prime importance among Health Care Professionals (HCPs) and non-compliance could cause adverse consequences. By keeping the importance of HH in mind, this study aims at investigating the knowledge and attitudes towards HH among medical students and interns at King Abdulaziz University (KAU), Jeddah, Saudi Arabia (SA). Methods The study includes 453 medical students and interns (189 males & 264 females). This study was completed in three months; from September to November 2017. The World Health Organization (WHO) HH questionnaire was used and data were analyzed on SPSS-21. Results Two-third of the participants 292 (64.2%) had formal training in HH in the last three years. Almost half of the participants 254 (56.1%) had correct knowledge regarding the major course of transmission of potentially detrimental microbes among patients in the healthcare premises. Just 124 (27.4%) of the respondents had the correct knowledge about the most common basis of germs accountable for healthcare-related infections. Females had significantly better knowledge than males regarding the type of HH technique needed before palpation of the abdomen (177(54%) Vs. 151(46%); P < 0.002), before an injection (175(54.5%) Vs. 146(45.5%); P < 0.007), after emptying a bedpan (207(64.7%) Vs. 113(35.3%); P < 0.001), following discarding examination gloves (256(60.4% Vs. 168(39.6%); P < 0.001] and after exposure to blood (200(64.1%) Vs. 112(35.%); P < 0.001). Female participants had better knowledge than males regarding the type of HH actions. Females also had a significantly better attitude towards the importance of HH than males (240(62.5%) Vs. 144(37.5%); P < 0.001). Conclusion The majority of the participants’ knowledge regarding HH was not up to the mark; however, female students had better knowledge compared to male students. The medical students and interns’ knowledge and positive attitude towards HH can play a pivotal role in preventing HCPs associated infections and it would overall decrease the infection-related burden on the hospital and governmental budgets. It is suggested that multi-dimensional plans are required to change this low compliance to a higher rate