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1.
Crit Care Med ; 52(5): 683-693, 2024 05 01.
Article in English | MEDLINE | ID: mdl-38236076

ABSTRACT

OBJECTIVES: The COVID-19 pandemic significantly impacted global healthcare systems, particularly in managing critically ill mechanically ventilated patients. This study aims to assess the feasibility of robotic-assisted mobilization in COVID-19 patients. DESIGN: Randomized controlled pilot study. SETTING: Four COVID-19 specialized ICUs at Charité-Universitätsmedizin Berlin (March 2021 to February 2022). PATIENTS: Twenty critically ill COVID-19 patients expected to require greater than 24 hours of ventilation. INTERVENTIONS: A 5-day intervention phase with bid robotic-assisted mobilization greater than or equal to 20 minutes and follow-up at day 180, compared with standard care. MEASUREMENTS AND MAIN RESULTS: Intervention sessions were conducted in 98.9% according to protocol, with one session missing due to staff shortage. Primary outcome was the mobilization level measured with the ICU Mobility Scale (IMS) and Surgical ICU Optimal Mobilization Score (SOMS), assessed until day 5 or extubation. Safety events were recorded during mobilization. The median IMS and SOMS were 0 (0-0.16) and 1 (1-1.03) in the intervention group, and 0 (0-0.15) ( p = 0.77) and 0.8 (0.65-1.20) ( p = 0.08) in the standard care group, respectively. Significant secondary outcomes included average number of mobilization sessions (intervention: 8.5 [7.75-10] vs. standard care: 4.5 [3.5-5]; p = 0.001), total mobilization time (intervention: 232.5 min [187.25-266.5 min] vs. standard care: 147.5 min [107.5-167.5 min]; p = 0.011), and healthcare providers per session (intervention: 2 [2-2] vs. standard care: 1 [1-1.4]; p = 0.001) during intervention. Four safety events (hypertension and agitation, n = 2 each) in the intervention group and none in the standard care group were reported. CONCLUSIONS: Robotic-assisted mobilization in mechanically ventilated COVID-19 patients appears to be safe and feasible.


Subject(s)
COVID-19 , Robotic Surgical Procedures , Humans , Pilot Projects , Critical Illness , Pandemics , Respiration, Artificial/methods , Intensive Care Units
2.
J Intensive Care ; 11(1): 56, 2023 Nov 20.
Article in English | MEDLINE | ID: mdl-37986100

ABSTRACT

BACKGROUND: This study aimed to assess the impact of duration of early mobilisation on survivors of critical illness. The hypothesis was that interventions lasting over 40 min, as per the German guideline, positively affect the functional status at ICU discharge. METHODS: Prospective single-centre cohort study conducted in two ICUs in Germany. In 684 critically ill patients surviving an ICU stay > 24 h, out-of-bed mobilisation of more than 40 min was evaluated. RESULTS: Daily mobilisation ≥ 40 min was identified as an independent predictor of an improved functional status upon ICU discharge. This effect on the primary outcome measure, change of Mobility-Barthel until ICU discharge, was observed in three different models for baseline patient characteristics (average treatment effect (ATE), all three models p < 0.001). When mobilisation parameters like level of mobilisation, were included in the analysis, the average treatment effect disappeared [ATE 1.0 (95% CI - 0.4 to 2.4), p = 0.16]. CONCLUSIONS: A mobilisation duration of more than 40 min positively impacts functional outcomes at ICU discharge. However, the maximum level achieved during ICU stay was the most crucial factor regarding adequate dosage, as higher duration did not show an additional benefit in patients with already high mobilisation levels. TRIAL REGISTRATION: Prospective Registry of Mobilization-, Routine- and Outcome Data of Intensive Care Patients (MOBDB), NCT03666286. Registered 11 September 2018-retrospectively registered, https://classic. CLINICALTRIALS: gov/ct2/show/NCT03666286 .

4.
PLoS One ; 18(2): e0278751, 2023.
Article in English | MEDLINE | ID: mdl-36809526

ABSTRACT

Algorithms already carry out many tasks more reliably than human experts. Nevertheless, some subjects have an aversion towards algorithms. In some decision-making situations an error can have serious consequences, in others not. In the context of a framing experiment, we examine the connection between the consequences of a decision-making situation and the frequency of algorithm aversion. This shows that the more serious the consequences of a decision are, the more frequently algorithm aversion occurs. Particularly in the case of very important decisions, algorithm aversion thus leads to a reduction of the probability of success. This can be described as the tragedy of algorithm aversion.


Subject(s)
Affect , Decision Making , Humans , Probability , Algorithms
5.
Crit Care ; 27(1): 1, 2023 01 03.
Article in English | MEDLINE | ID: mdl-36597110

ABSTRACT

BACKGROUND: While early mobilization is commonly implemented in intensive care unit treatment guidelines to improve functional outcome, the characterization of the optimal individual dosage (frequency, level or duration) remains unclear. The aim of this study was to demonstrate that artificial intelligence-based clustering of a large ICU cohort can provide individualized mobilization recommendations that have a positive impact on the likelihood of being discharged home. METHODS: This study is an analysis of a prospective observational database of two interdisciplinary intensive care units in Munich, Germany. Dosage of mobilization is determined by sessions per day, mean duration, early mobilization as well as average and maximum level achieved. A k-means cluster analysis was conducted including collected parameters at ICU admission to generate clinically definable clusters. RESULTS: Between April 2017 and May 2019, 948 patients were included. Four different clusters were identified, comprising "Young Trauma," "Severely ill & Frail," "Old non-frail" and "Middle-aged" patients. Early mobilization (< 72 h) was the most important factor to be discharged home in "Young Trauma" patients (ORadj 10.0 [2.8 to 44.0], p < 0.001). In the cluster of "Middle-aged" patients, the likelihood to be discharged home increased with each mobilization level, to a maximum 24-fold increased likelihood for ambulating (ORadj 24.0 [7.4 to 86.1], p < 0.001). The likelihood increased significantly when standing or ambulating was achieved in the older, non-frail cluster (ORadj 4.7 [1.2 to 23.2], p = 0.035 and ORadj 8.1 [1.8 to 45.8], p = 0.010). CONCLUSIONS: An artificial intelligence-based learning approach was able to divide a heterogeneous critical care cohort into four clusters, which differed significantly in their clinical characteristics and in their mobilization parameters. Depending on the cluster, different mobilization strategies supported the likelihood of being discharged home enabling an individualized and resource-optimized mobilization approach. TRIAL REGISTRATION: Clinical Trials NCT03666286, retrospectively registered 04 September 2018.


Subject(s)
Artificial Intelligence , Critical Illness , Humans , Middle Aged , Critical Illness/therapy , Intensive Care Units , Critical Care , Hospitalization , Early Ambulation
6.
Sci Rep ; 12(1): 10866, 2022 06 27.
Article in English | MEDLINE | ID: mdl-35760830

ABSTRACT

Seizures are a common reason for calling emergency medical services. A lack of guidelines on prehospital treatment in Germany leads to high transportation rates and reduced confidence in decision making by professionals. Our aim was to investigate the reasons for hospitalization and evaluate their necessity. A retrospective analysis of all emergency medical services records in Munich, Germany was performed in order to examine the reasons for hospitalization of patients with seizures and to evaluate their trajectory following admission to a university hospital. 8882 records were analyzed with 415 records reporting seizures (4.9%). Primary endpoint was transportation to hospital. In 380 cases (92%) patients were transported, of which 177 patients (47%) had known epilepsy; 35 patients (8%) were left at scene. Older patients and patients with higher amounts of administered medication at the scene were hospitalized significantly more often (p = 0.032 and p = 0.004, respectively). Median hospital length of stay was 1 night [IQR 1-2]. In patients with out-of-hospital seizures, high hospital transportation rates were evident, most of which could be considered as not indicated. One possible reason is the lack of guidelines in Germany, which leads to uncertainty among medical staff. This results in distress for the patients, their caregivers and consequently high costs.


Subject(s)
Emergency Medical Services , Germany/epidemiology , Hospitalization , Humans , Retrospective Studies , Seizures/epidemiology , Seizures/therapy
7.
Front Med (Lausanne) ; 8: 748812, 2021.
Article in English | MEDLINE | ID: mdl-34805218

ABSTRACT

Background: Long-term outcome is determined not only by the acute critical illness but increasingly by the reduced functional reserve of pre-existing frailty. The patients with frailty currently account for one-third of the critically ill, resulting in higher mortality. There is evidence of how frailty affects the intrahospital functional trajectory of critically ill patients since prehospital status is often missing. Methods: In this prospective single-center cohort study at two interdisciplinary intensive care units (ICUs) at a university hospital in Germany, the frailty was assessed using the Clinical Frailty Scale (CFS) in the adult patients with critical illness with an ICU stay >24 h. The functional status was assessed using the sum of the subdomains "Mobility" and "Transfer" of the Barthel Index (MTB) at three time points (pre-hospital, ICU discharge, and hospital discharge). Results: We included 1,172 patients with a median age of 75 years, of which 290 patients (25%) were frail. In a propensity score-matched cohort, the probability of MTB deterioration till hospital discharge did not differ in the patients with frailty (odds ratio (OR) 1.3 [95% CI 0.8-1.9], p = 0.301), confirmed in several sensitivity analyses in all the patients and survivors only. Conclusion: The patients with frailty have a reduced functional status. Their intrahospital functional trajectory, however, was not worse than those in non-frail patients, suggesting a rehabilitation potential of function in critically ill patients with frailty.

8.
Sci Rep ; 11(1): 16317, 2021 08 11.
Article in English | MEDLINE | ID: mdl-34381086

ABSTRACT

Diaphragm weakness affects up to 60% of ventilated patients leading to muscle atrophy, reduction of muscle fiber force via muscle fiber injuries and prolonged weaning from mechanical ventilation. Electromagnetic stimulation of the phrenic nerve can induce contractions of the diaphragm and potentially prevent and treat loss of muscular function. Recommended safety distance of electromagnetic coils is 1 m. The aim of this study was to investigate the magnetic flux density in a typical intensive care unit (ICU) setting. Simulation of magnetic flux density generated by a butterfly coil was performed in a Berlin ICU training center with testing of potential disturbance and heating of medical equipment. Approximate safety distances to surrounding medical ICU equipment were additionally measured in an ICU training center in Bern. Magnetic flux density declined exponentially with advancing distance from the stimulation coil. Above a coil distance of 300 mm with stimulation of 100% power the signal could not be distinguished from the surrounding magnetic background noise. Electromagnetic stimulation of the phrenic nerve for diaphragm contraction in an intensive care unit setting seems to be safe and feasible from a technical point of view with a distance above 300 mm to ICU equipment from the stimulation coil.


Subject(s)
Phrenic Nerve/physiopathology , Safety Management/methods , Berlin , Diaphragm/physiopathology , Electromagnetic Phenomena , Humans , Intensive Care Units , Muscle Contraction/physiology , Muscle Weakness/physiopathology , Muscular Atrophy/physiopathology , Respiration, Artificial/methods
9.
Resuscitation ; 166: 85-92, 2021 09.
Article in English | MEDLINE | ID: mdl-34302927

ABSTRACT

AIM OF THE STUDY: Automated mechanical chest compression devices (AMCCDs) can help performing high-quality cardiopulmonary resuscitation (CPR). Guidelines for CPR are lacking information about the optimal ventilation mode during CPR using AMCCDs. Aim of this pilot study was to compare three common ventilation modes during CPR using AMCCD. METHODS: In this randomized controlled trial, we included patients with an out-of-hospital cardiac arrest arriving at the resuscitation room receiving chest compressions via AMCCD with an expected continuation of at least 15 min. Patients were randomly assigned to three groups: biphasic positive airway pressure with assisted spontaneous ventilation (BIPAP) with assisted spontaneous breathing, continuous positive airway pressure (CPAP) and volume-controlled ventilation (VCV). Outcomes were tidal volume, respiratory minute volume, and end-tidal CO2 during the study period. Groups were compared using generalized linear models. Data is given as median and interquartile ranges. RESULTS: Of 53 screened patients, 30 were randomized. The tidal volume was significantly (p < 0.05) lower in patients of the CPAP group (68 [64-83] ml) compared with those of the BIPAP (349 [137-500] ml), while the respiratory minute volume differed between the CPAP group (6.2 [5.3-8.1] l/min) and both the BIPAP (7.1 [6.7-10.2] l/min) and VCV group (7.2 [3.7-8.4] l/min). CONCLUSIONS: All ventilation modes achieved an adequate respiratory minute volume during CPR with an AMCCD. However, BIPAP seems to be superior due to the higher tidal volume. Therefore, we recommend starting mechanical ventilation when using AMCCD with BIPAP ventilation to avoid risks related to dead space ventilation.


Subject(s)
Cardiopulmonary Resuscitation , Out-of-Hospital Cardiac Arrest , Humans , Out-of-Hospital Cardiac Arrest/therapy , Pilot Projects , Respiration, Artificial , Tidal Volume
10.
Phys Chem Chem Phys ; 18(30): 20270-5, 2016 Jul 27.
Article in English | MEDLINE | ID: mdl-27406407

ABSTRACT

Boron nitride-substituted graphene (BNsG) two-dimensional structures are new materials of wide technological interest due to the rich variety of electronic structures and properties they can exploit. The ability to accurately characterize them is key to their future success. Here we show, by means of ab initio simulations, that the vibrational Raman spectra of such compounds are extremely sensitive to substitution motifs and concentration, and that each structure has unique and distinct features. This result can be useful as a guide for the optimization of production processes.

11.
J Comput Chem ; 35(24): 1789-800, 2014 Sep 15.
Article in English | MEDLINE | ID: mdl-25056422

ABSTRACT

The physisorption of water on graphene is investigated with the hybrid density functional theory (DFT)-functional B3LYP combined with empirical corrections, using moderate-sized basis sets such as 6-31G(d). This setup allows to model the interaction of water with graphene going beyond the quality of classical or semiclassical simulations, while still keeping the computational costs under control. Good agreement with respect to Coupled Cluster with singles and doubles excitations and perturbative triples (CCSD(T)) results is achieved for the adsorption of a single water molecule in a benchmark with two DFT-functionals (Perdew/Burke/Ernzerhof (PBE), B3LYP) and Grimme's empirical dispersion and counterpoise corrections. We apply the same setting to graphene supported by epitaxial hexagonal boron nitride (h-BN), leading to an increased interaction energy. To further demonstrate the achievement of the empirical corrections, we model, entirely from first principles, the electronic properties of graphene and graphene supported by h-BN covered with different amounts of water (one, 10 water molecules per cell and full coverage). The effect of h-BN on these properties turns out to be negligibly small, making it a good candidate for a substrate to grow graphene on.

12.
J Environ Manage ; 127 Suppl: S37-47, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23751946

ABSTRACT

Regarding increasing pressures by global societal and climate change, the assessment of the impact of land use and land management practices on land degradation and the related decrease in sustainable provision of ecosystem services gains increasing interest. Existing approaches to assess agricultural practices focus on the assessment of single crops or statistical data because spatially explicit information on practically applied crop rotations is mostly not available. This provokes considerable uncertainties in crop production models as regional specifics have to be neglected or cannot be considered in an appropriate way. In a case study in Saxony, we developed an approach to (i) derive representative regional crop rotations by combining different data sources and expert knowledge. This includes the integration of innovative crop sequences related to bio-energy production or organic farming and different soil tillage, soil management and soil protection techniques. Furthermore, (ii) we developed a regionalization approach for transferring crop rotations and related soil management strategies on the basis of statistical data and spatially explicit data taken from so called field blocks. These field blocks are the smallest spatial entity for which agricultural practices must be reported to apply for agricultural funding within the frame of the European Agricultural Fund for Rural Development (EAFRD) program. The information was finally integrated into the spatial decision support tool GISCAME to assess and visualize in spatially explicit manner the impact of alternative agricultural land use strategies on soil erosion risk and ecosystem services provision. Objective of this paper is to present the approach how to create spatially explicit information on agricultural management practices for a study area around Dresden, the capital of the German Federal State Saxony.


Subject(s)
Agriculture/methods , Crops, Agricultural , Environmental Monitoring/methods , Conservation of Natural Resources , Ecosystem , Soil
13.
J Chem Phys ; 137(20): 204119, 2012 Nov 28.
Article in English | MEDLINE | ID: mdl-23205993

ABSTRACT

We present a density fitted local configuration interaction singles (CIS) method for calculating optical bandgaps in 3D-periodic systems. We employ an Ewald technique to carry out infinite lattice summations for the exciton-exciton interaction, and robust product-density specific local density fitting in direct space for the electron-hole interaction. Moreover, we propose an alternative to the usual cyclic model with Born-von Karman periodic boundary conditions, the so called Wigner-Seitz supercell truncated infinite model, which exhibits much improved convergence of the CIS excitation energy with respect to the size of the supercell. Test calculations on a series of prototypical systems demonstrate that the method at the present stage can be used to calculate the excitonic bandgaps of 3D periodic systems with up to a dozen atoms in the unit cell, ranging from wide-gap insulators to semiconductors.

14.
Phys Chem Chem Phys ; 14(21): 7615-28, 2012 Jun 07.
Article in English | MEDLINE | ID: mdl-22334044

ABSTRACT

Cryscor is a periodic post-Hartree-Fock program based on local functions in direct space, i.e., Wannier functions and projected atomic orbitals. It uses atom centered Gaussians as basis functions. The Hartree-Fock reference, as well as symmetry information, is provided by the Crystal program. Cryscor presently features an efficient and parallel implementation of periodic local second order Møller-Plesset perturbation theory (MP2), which allows us to study 1D-, 2D- and 3D-periodic systems beyond 1000 basis functions per unit cell. Apart from the correlation energy also the MP2 density matrix, and from that the Compton profile, are available. Very recently, a new module for calculating excitonic band gaps at the uncorrelated Configuration-Interaction-Singles (CIS) level has been added. Other advancements include new extrapolation techniques for calculating surface adsorption on semi-infinite solids. In this paper the diverse features and recent advances of the present Cryscor version are illustrated by exemplary applications to various systems: the adsorption of an argon monolayer on the MgO (100) surface, the rolling energy of a boron nitride nanoscroll, the relative stability of different aluminosilicates, the inclusion energy of methane in methane-ice-clathrates, and the effect of electron correlation on charge and momentum density of α-quartz. Furthermore, we present some first tentative CIS results for excitonic band gaps of simple 3D-crystals, and their dependence on the diffuseness of the basis set.

15.
J Chem Phys ; 134(9): 094101, 2011 Mar 07.
Article in English | MEDLINE | ID: mdl-21384944

ABSTRACT

We present a density fitted local configuration interaction singles (CIS) method for calculating optical band gaps in 1D-periodic systems. The method is based on the Davidson diagonalization procedure, carried out in the reciprocal space. The one-electron part of the matrix-vector products is also evaluated in the reciprocal space, where the diagonality of the Fock matrix can be exploited. The contraction of the CIS vectors with the two electron integrals is performed in the direct space in the basis of localized occupied (Wannier) and virtual (projected atomic) orbitals. The direct space approach allows to utilize the sparsity of the integrals due to the local representation and locality of the exciton. The density fitting approximation employed for the two electron integrals reduces the nominal scaling with unit cell size to O(N(4)). Test calculations on a series of prototypical systems demonstrate that the method in its present stage can be used to calculate the excitonic band gaps of polymers with up to a few dozens of atoms in the cell. The computational cost depends on the locality of the exciton, but even relatively delocalized excitons occurring in the polybiphenyl in the parallel orientation, can be routinely treated with this method.


Subject(s)
Polymers/chemistry , Quantum Theory
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