Postoperative cognitive dysfunction: a concept analysis.

BACKGROUND: Post-operative cognitive dysfunction (POCD) is a concern for clinicians that often presents post-surgery where generalized anesthesia has been used. Its prevalence ranges from 36.6% in young adults to 42.4% in older individuals. Conceptual clarity for POCD is lacking in the currently body literature. Our two-fold purpose of this concept analysis was to (1) critically appraise the various definitions, while also providing the best definition, of POCD and (2) narratively synthesize the attributes, surrogate or related terms, antecedents (risk factors), and consequences of the concept. METHOD: The reporting of our review was guided by the PRISMA statement and the 6-step evolutionary approach to concept analysis developed by Rodgers. Three databases, including Medline, CINAHL, and Web of Science, were searched to retrieve relevant literature on the concept of POCD. Two independent reviewers conducted abstract and full-text screening, data extraction, and appraisal. The review process yielded a final set of 86 eligible articles. RESULT: POCD was defined with varying severities ranging from subtle-to-extensive cognitive changes (1) affecting single or multiple cognitive domains that manifest following major surgery (2), is transient and reversible, and (3) may last for several weeks to years. The consequences of POCD may include impaired quality of life, resulting from withdrawal from the labor force, increased patients' dependencies, cognitive decline, an elevated risk of dementia, rising healthcare costs, and eventual mortality. CONCLUSION: This review resulted in a refined definition and comprehensive analysis of POCD that can be useful to both researchers and clinicians. Future research is needed to refine the operational definitions of POCD so that they better represent the defining attributes of the concept.

User Based Development and Test of the EXOTIC Exoskeleton: Empowering Individuals with Tetraplegia Using a Compact, Versatile, 5-DoF Upper Limb Exoskeleton Controlled through Intelligent Semi-Automated Shared Tongue Control.

This paper presents the EXOTIC- a novel assistive upper limb exoskeleton for individuals with complete functional tetraplegia that provides an unprecedented level of versatility and control. The current literature on exoskeletons mainly focuses on the basic technical aspects of exoskeleton design and control while the context in which these exoskeletons should function is less or not prioritized even though it poses important technical requirements. We considered all sources of design requirements, from the basic technical functions to the real-world practical application. The EXOTIC features: (1) a compact, safe, wheelchair-mountable, easy to don and doff exoskeleton capable of facilitating multiple highly desired activities of daily living for individuals with tetraplegia; (2) a semi-automated computer vision guidance system that can be enabled by the user when relevant; (3) a tongue control interface allowing for full, volitional, and continuous control over all possible motions of the exoskeleton. The EXOTIC was tested on ten able-bodied individuals and three users with tetraplegia caused by spinal cord injury. During the tests the EXOTIC succeeded in fully assisting tasks such as drinking and picking up snacks, even for users with complete functional tetraplegia and the need for a ventilator. The users confirmed the usability of the EXOTIC.

Effects of Exercise on COVID-19 Patients: A Narrative Review.

Background: Challenges concerning patient management exist worldwide, particularly in the critical care. In this review, we have summarized some studies regarding respiratory physiotherapy and exercise in COVID-19 patients. Methods: For searching related articles, PubMed, Google Scholar, Embase, and the Web of Science databases were used. Keywords such as "respiratory physiotherapy" and "COVID-19," "exercise," "effect of exercise in COVID-19," and "respiratory physiotherapy for COVID-19 in ICU" were used to identify related papers until December 2021. The abstracts and entire texts were evaluated by 3 separate reviewers. Results: During the symptomatic phase, individuals may benefit from brief durations of bed rest. Exercise appears to provide both emotional and physical benefits for individuals in the early stages of infection. As a result, it may lower viral load, minimize cytokine storm, shorten the acute phase, and expedite recovery. Mild exercise may also increase the autophagy pathway, which improves the immune system function in response to COVID-19 infection. Keeping this in mind, intense activity, especially without the guidance of an expert physical therapist, is not advantageous during the inflammatory period and may even be regarded a second hit phenomenon. Mild exercises during bed rest (e.g., acute phase) may reduce the risk of pulmonary capillary coagulation and deep vein thrombosis. Conclusion: Although respiratory physiotherapy and prone positioning in hospitalized patients, particularly in critical care, can be challenging for medical staff, they are cost-effective and noninvasive approaches for COVID-19 patients. Early physiotherapy and muscle training exercise for patients in the intensive care unit (ICU) seems to be beneficial for patients and may reduce bed rest-induced weakness, improve oxygenation, and reduce length of stay. Finally, breathing exercises can improve some symptoms of COVID-19, like dyspnea and weakness.

Soluble ACE2 as a Risk or Prognostic Factor in COVID-19 Patients: A Cross-sectional Study.

Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel severe acute respiratory syndrome coronavirus. The first known receptor for this virus in the human body is angiotensin-converting enzyme 2 (ACE2), the same receptor for the SARS virus. Methods: A total of 38 hospitalized adult (18 years) patients with laboratory or clinically confirmed coronavirus disease 2019 (COVID-19) were identified in the infectious disease ward of Tehran Imam Khomeini hospital complex in this single-center cross-sectional study. A blood sample was taken at the time of hospitalization and a second one was taken 48 hours later. Blood samples are kept frozen at -80 degrees Celsius. After the complete collection of samples, the ACE2 level of the samples was measured using a serum sACE2 detection ELISA kit. The data were analyzed using SPSS v26. P value of 0.05 was considered statistically significant. An analysis of covariance was performed to examine the mean differences in day 7 serum ACE2 concentration among the 2 groups after adjusting for the baseline serum ACE2 concentration. The 1-way multivariate analysis of variance was used to determine whether there were any differences between independent groups (mechanical ventilation yes/no) on serum ACE2 levels at 3 different times. Results: The mean age of patients was 64.13 ± 16.49 years, 21 patients (55.3%) were men, 16 patients (42%) were polymerase chain reaction test positive, and 15 patients (39.5%) died. A total of 35 individuals (92.1%) had chest computed tomography images that indicated lung involvement. A comparison of the 2 groups of patients who died and were discharged revealed that serum ACE2 at the first (p=0.033) and third (7th day) measurements were statistically different (p=0.026). Patients had a mean of serum ACE2. The results indicated that the day 7 serum ACE2 concentration did significantly differ between the 2 groups after controlling for the baseline serum ACE2 concentration (p=0.023). The model explained about 73.61% of the variance in the 7-day serum ACE2 concentration. Specifically, after adjusting for the baseline concentration, survived patients had the lowest level of serum ACE2 concentration (1 ± 0.65) on the 7th day compared with the deceased patient group (2.83 ± 1.12). Conclusion: Soluble ACE2 in the serum of COVID-19 patients who died, later on, was significantly higher than the discharged patients when the samples were taken seven days after admission. It is suggested that serum soluble ACE2 level could be used as a prognostic factor for COVID-19 patients' outcomes and also their need for mechanical ventilation.

Topical Nifedipine for the Treatment of Pressure Ulcer: A Randomized, Placebo-Controlled Clinical Trial.

BACKGROUND: Effect of nifedipine on pressure ulcer (PU) healing has not been evaluated in the human subjects yet. STUDY QUESTION: In this study, the effect of topical application of nifedipine 3% ointment on PU healing in critically ill patients was investigated. STUDY DESIGN: This was a randomized, double-blind, placebo-controlled clinical. MEASURES AND OUTCOMES: In this study, 200 patients with stage I or II PU according to 2-digit Stirling Pressure Ulcer Severity Scale were randomized to receive topical nifedipine 3% ointment or placebo twice daily for 14 days. Changes in the size and stage of the ulcers were considered as primary outcome of the study. The stage of the ulcers at baseline and on day 7 and day 14 of study was determined by using 2-digit stirling scale. In addition, the surface area of the wounds was estimated by multiplying width by length. RESULTS: In total, 83 patients in each group completed the study. The groups were matched for the baseline stage and size of PUs. Mean decrease in the stage of PU in the nifedipine group was significantly higher than the placebo group on day 7 (-1.71 vs. -0.16, respectively, P < 0.001) and day 14 (-0.78 vs. -0.09, respectively, P < 0.001). Furthermore, the mean decrease in the surface area of PU was significantly higher in the nifedipine group compared with the placebo group on day 7 (-1.44 vs. -0.32, respectively, P < 0.001) and day 14 (-2.51 vs. -0.24, respectively, P < 0.001) of study. CONCLUSIONS: Topical application of nifedipine 3% ointment for 14 days significantly improved the healing process of stage I or II PUs in critically ill patients.

Early Hemoperfusion for Cytokine Removal May Contribute to Prevention of Intubation in Patients Infected with COVID-19.

Hemoperfusion (HP) was helpful to prevent the development and progression of acute respiratory distress syndrome (ARDS), acute kidney injury (AKI), liver failure, and septic shock by removing cytokines and other inflammatory mediators and ultimately preventing progression toward multiple organ failure. A 54-year-old man diagnosed with COVID-19 was hospitalized in the intensive care unit. The patient's O2 saturation was 80% using an oxygen mask, which was gradually declining. After 4 sessions of HP/continuous renal replacement therapies (CRRT), O2 saturation reached to 95%, and the patient was transferred to the general ward. Performing HP/CRRT at the early stages of ARDS can obviate the need for intubating patients with COVID-19. Punctual and early use of HP and CRRT in the treatment of ARDS in patients with COVID-19 prevented the progression of ARDS and patient intubation, reduced respiratory distress and the patient's dependence on oxygen, prevented other complications such as AKI and septic shock in the patient, and reduced mortality and hospital length of stay.

Effect of magnesium supplementation on lactate clearance in critically ill patients with severe sepsis: a randomized clinical trial.

OBJECTIVES: In this study, changes in lactate clearance following magnesium supplementation were evaluated in critically ill patients with severe sepsis. METHODS: Fifty-eight patients with severe sepsis were randomly assigned to receive either magnesium (n = 30) or placebo (n = 28). Patients in the magnesium group received intravenous magnesium sulfate to maintain serum magnesium level around 3 mg/dL for 3 days. The placebo group received the same volume of normal saline. Change in lactate clearance was considered primary outcome of the study. RESULTS: Mean increase in the lactate clearance in the magnesium group was significantly higher than the placebo group on day 2 (27.53% vs. 23.79% respectively, p < 0.001) and day 3 (49.83% vs. 37.02% respectively, p < 0.001). Time to lactate clearance was also significantly shorter in the magnesium group than the placebo group (47.28 ± 20.59 vs. 61.20 ± 24.31 h respectively, p = 0.03). Sepsis-related mortality was not significantly different but median length of ICU stay was significantly shorter in the magnesium group than the placebo group (8 vs. 15 days respectively, p < 0.01). CONCLUSIONS: Magnesium supplementation increased lactate clearance in critically ill patients with severe sepsis. Optimizing serum magnesium level near the upper limit of the normal range may improve severe sepsis outcomes.

Effect of Magnesium Loading Dose on Insulin Resistance in Patients With Stress-Induced Hyperglycemia: A Randomized Clinical Trial.

OBJECTIVES: There is currently no evidence that whether magnesium supplementation would improve stress-induced hyperglycemia (SIH) in critically ill patients. In this study, effects of magnesium loading dose on insulin resistance (IR) indices were evaluated in critically ill patients without diabetes having SIH. METHODS: Seventy critically ill patients with SIH were assigned to receive a loading dose of magnesium (7.5 g of magnesium sulfate in 500 mL normal saline as intravenous infusion over an 8-hour period) or placebo. Changes in baseline of serum and intracellular magnesium and serum adiponectin (AD) levels, homeostasis model assessment of IR (HOMA-IR), and HOMA-AD ratio were assessed in this study. RESULTS: Serum and intracellular magnesium levels increased significantly in patients in the magnesium group (P < .001). At day 3, there were significant differences between the magnesium group and the placebo group in the mean changes from baseline in the HOMA (between-group difference: -0.11; 95% confidence interval [CI]: -0.19 to -0.01; P = .02), the AD (between-group difference: 0.94; 95% CI: 0.41-1.48; P = .04), and the HOMA-AD ratio (between-group difference: -0.03; 95% CI: -0.04 to -0.01; P < .001). CONCLUSION: In the present study, a single-loading dose of intravenous magnesium improved IR indices in critically ill patients with SIH.

Prediction of environmental effects in received signal strength in FM/TV station based on meteorological parameters using artificial neural network and data mining.

In this paper, meteorological parameters, electric field strength and transmitters' output power measured during six months in a TV/FM station. There are 13 frequencies in FM and UHF frequency bands in pilot broadcast station. The analysis of results were carried out using data mining techniques. In addition, a prediction model on the basis of a Neural Network is identified. The electric field is affected by distance between the antenna and the receiver point, transmitters' output power and meteorological constituents of air pressure, temperature and humidity. The meteorological parameters and transmitters' power are used as inputs and the electric field is used as the output. After data acquisition, preprocessing is performed and the Neural Network of a multilayer perceptron model is applied. In addition, Multi Linear Regression is performed. In evaluation, the performance of the proposed techniques is based on the root mean square error (RMSE) property. The least MSE obtained for the proposed model based on Neural Network amounted to 0.198 while the least MSE of Regression was 0.280. The results showed that for a given input of the atmospheric parameters as well as the transmitter power, the intensity of electric field can be predicted as well as the determining the relationship between the atmospheric parameters, transmitters' power and electric field strength. The statistical and correlation analysis used to assess the relation between each parameter and signal strength concluded that the temperature and wind direction have an inverted linear relationship with the signal level while the others have a direct linear relationship.

Topical pentoxifylline for pressure ulcer treatment: a randomised, double-blind, placebo-controlled clinical trial.

OBJECTIVE: To evaluate the effectiveness of topical pentoxifylline (PTX) on pressure ulcer (PU) healing in critically ill patients. METHOD: In this randomised, double blind, placebo-controlled clinical trial, patients with category I or II PUs were randomly assigned to receive either topical PTX 5% or a placebo twice daily for 14 days. Changes in PU characteristics (category and size) were assessed. The category of the PU was determined by the Stirling Pressure Ulcer Severity Scale (two-digit) at baseline (day zero), day seven and day 14 of treatment. PU length and width was measured with a disposable ruler and expressed as cm2. RESULTS: A total of 112 adult patients were enrolled in the study. Median PU size and score at day zero were 32 (10.00-69.33)cm2 and 1(1.00-2.00) respectively. In the PTX group, the mean differences (95% confidence interval, CI) of all PU scores and sizes decreased significantly across the intervals (day seven versus day zero, day 14 versus day zero, and day 14 versus day seven), compared with the placebo group Conclusion: The severity and size of PUs improved significantly in patients who received topical PTX 5% ointment twice a day for 14 days compared with those in the placebo group. Topical PTX may be considered as a potential option in the treatment of categories I and II PUs in critically ill patients.

Cyproheptadine for the Prevention of Postoperative Delirium: A Pilot Study.

BACKGROUND: Postoperative delirium is a common neurobehavioral complication after major surgeries. There is no conclusive approach for prevention of delirium in these patients. OBJECTIVE: In this study, efficacy of cyproheptadine for prevention of postoperative delirium was evaluated. METHODS: Delirium status of surgical patients was evaluated postoperatively at the time of admission to the intensive care unit (ICU) using the Confusion Assessment Method (CAM-ICU) scale. Patients without delirium were assigned to the cyproheptadine or placebo group based on the simple randomization method. Patients received cyproheptadine or placebo tablet at a dose of 4 mg 3 times per day for 7 days. Patients were monitored daily for incidence of delirium. RESULTS: Changes in the incidence rates of delirium over time during the study phase (P = 0.04) and between the groups showed statistically significant differences (P = 0.029). However, severity of delirium was not significantly different between the cyproheptadine and placebo groups during the study period. CONCLUSION: It seems that cyproheptadine with its diverse effects can be a potential option for prevention of postoperative delirium. In this pilot study, cyproheptadine significantly decreased the incidence but not severity of postoperative delirium.

The Protective Effect of α-Hederin, the Active Constituent of Nigella sativa, on Lung Inflammation and Blood Cytokines in Ovalbumin Sensitized Guinea Pigs.

In the present study, the preventive effect of two different concentrations of α-hederin, the active constituent of Nigella sativa, on lung inflammation and blood cytokines in ovalbumin sensitized guinea pigs was examined. Forty eight male adult guinea pigs were divided into control (C), sensitized (S) and sensitized pretreated groups; with thymoquinone (S+TQ), low dose (S+LAH) and high dose of α-hederin (S+HAH) and inhaled fluticasone propionate (S+FP). The lung histopathology and blood levels of IL-4, IFN-γ and IL-17 were assessed. Compared to sensitized animals, all pathological changes improved significantly in pretreated groups (p < 0.001 to p < 0.05). These improvements in α-hederin pretreated groups were similar to S+TQ and S+FP groups except cellular infiltration in S+LAH and S+HAH groups which was lower than S+TQ group (p < 0.05). The blood IL-4 and IL-17 levels in S+HAH groups showed a significant decrease compared to S group (p < 0.05) which were similar to S+TQ and S+FP groups. The level of IFN-γ in S+LAH and S+HAH groups increased significantly compared to S group (p < 0.05) which was higher than S+FP group (p < 0.05). Blood IL-4 in S+HAH group was significantly lower than S+LAH group (p < 0.05). In conclusion, α-hederin could attenuate the lung inflammation and improve the changes of cytokines like thymoquinone and fluticasone in used dosages.

An investigation of the associations between contingent self-worth and aspirations among Iranian university students.

This study investigated the novel associations between intrinsic and extrinsic aspirations and internal and external domains of contingent self-worth among a sample of 502 Iranian university students. We found a meaningful pattern showing that intrinsic aspirations were positively associated with internal domains, whereas extrinsic aspirations were positively associated with external domains. Our survey data also suggested that the factor structure of the Aspiration Index, as well as the factor structure of the Contingencies of Self-Worth Scale in our Iranian sample were consistent with factor structures of foreign samples. Finally, the types of aspirations and domains of contingencies of self-worth meaningfully predicted variables related to well-being, confirming previous research. We discuss the nature of the associations between the aspirations and the domains of contingent self-worth.

First diatom-based assessment of Lower Hari Rud River (a transboundary system) in Afghanistan.

It is essential to determine the dominant/indicator species and their ecological preferences to develop a comprehensive bioassessment strategy for rivers. The objective of this work was to provide dependable ecological evaluation techniques for ecosystems that experience significant human-induced disruptions, with the Hari Rud River (a transboundary water resource) serving as a case study during the May (wet) and July (dry) periods of 2023. Canonical correspondence analysis revealed that electrical conductivity (EC), dissolved oxygen, ortho-phosphate (P O 4 3 - ), and nitrate (N O 3 - ) had substantial impacts on the spatial distribution of diatom species in the basin. Relatively pollution-tolerant species, including Nitzschia brevissima, N. capitellata, N. umbonata, N. palea, N. dissipata, and Navicula cryptocephala, had close relationships with EC and P O 4 3 - , integrated with Joi Injil and Karbar streams. Of the sampling stations, especially Hari Rud River1 and Hari Rud River2, exhibited pollution-sensitive diatom species, Cymbella excisa, Achnanthidium minutissimum, Diatoma moniliformis, Cymbella affinis, and Meridion circulare. Various eco-regional diatom metrics exhibited distinct scores, indicating a range of ecological status from high to bad in the Lower Hari Rud River basin. European diatom indices revealed good ecological status for Hari Rud River 1 and 4, but poor or bad ecological statuses for Joi Injil and Karbar streams. The findings of the current study emphasize the requirements of autecological studies to understand the regional diatom compositions and their ideal survival ranges in different locations before considering using non-regional diatom indices to evaluate the ecological status of lotic systems.

Immediate effects of kinesiology tape on quadriceps muscle peak torque and knee joint repositioning error in healthy males: Effects of different tensions and directions.

BACKGROUND: Knee joint injuries may result from compromised quadriceps muscle strength or diminished knee joint proprioception. The application of Kinesio tape (KT) on the quadriceps muscle from origin to insertion (OTI-KT) or insertion to origin (ITO-KT) could impact knee joint proprioception and quadriceps muscle strength. This study aims to assess the effects of different tensions and directions of KT application on active and passive knee joint repositioning errors (AJRE and PJRE) and peak concentric and eccentric peak torque (CPT and EPT) of the quadriceps muscles in healthy males. METHOD: Twenty-one healthy males participated in this repeated-measures study design. CPT, EPT, AJRE, and PJRE of the dominant limb were measured by a Biodex dynamometer before and after applying OTI-KT with 0%, 15%, and 40% extra tensions and ITO-KT with 0% tension. RESULTS: ITO-KT demonstrated a significant reduction in AJRE (p < 0.05). Meanwhile, for OTI-KT, a statistically significant difference was observed in both AJRE and PJRE concerning time (F1,126 = 19.74, p < 0.05 for AJRE; F1,126 = 9.96, p < 0.05 for PJRE) and tension (F2,126 = 22.14, p < 0.05 for AJRE; F2,126 = 20.67, p < 0.05 for PJRE). CONCLUSION: Applying KT, especially OTI KT with 40% and 15% extra tension, shows potential in enhancing knee proprioception without immediate impacts on quadriceps muscle torque. This suggests applications in sports performance and knee injury rehabilitation.

Burden of nosocomial infections in intensive care units: Cost of antibiotics, the extra length of stay and mortality rate.

Background: Healthcare-associated infections (HAIs) in intensive care unit (ICU) patients significantly complicate the normal hospitalization process and affect patients' condition, length of hospitalization, mortality, and treatment cost. In this study, we aimed to determine the prevalence and economic burden of HAIs. Methods: The study involved all patients with a confirmed HAIs (based on CDC/NHSN case-definitions); in the general ICU of a tertiary university hospital in Tehran, from April 2020 to March 2021. The patients' information, including length of hospitalization, outcome, type and cost of prescribed antibiotics, were recorded. Results: During the study period, 119 HAIs were found in 1395 (43% F / 57% M) patients. The prevalence of nosocomial infections was 8.53%. The mean duration of hospitalization in all ICU patients was 4.7 ± 3.1 days, and 31.85 ± 18.96 days in patients with HAIs. The most common organisms involved in HAIs are Acinetobacter baumannii (54.6%), Klebsiella pneumoniae (30.3%), E. coli (15.1%), and Enterococcus spp. (12%). Incidence density of ventilator-associated pneumonia (VAP), central line-associated bloodstream infection (CLA-BSI), and catheter-associated urinary tract infection (CA-UTI) per 1000 device-days were 36.08, 17.57, and 8.86, respectively. The total cost of antibiotics for HAIs was € 105,407. Among these, the highest consumption costs were for carbapenems, followed by colistin and caspofungin. Conclusion: This study showed the high burden of nosocomial infections in ICUs. Strategies for more strict infection prevention and control are necessary to reduce this burden.

Adherence to recommendations for the evaluation and management of fungal infections in a referral teaching hospital in Iran: A retrospective cross-sectional study.

INTRODUCTION: Early diagnosis and appropriate management of fungal infections are critical for reducing complications and mortality in hospitalized patients. Due to the lack of appropriate local management protocols as well as the unavailability and cost of advanced tests for diagnosis of fungal infections, the irrational use of antifungals is a concern in developing countries. OBJECTIVES: This study was designed to evaluate diagnosis and management of fungal infections in hospitalized patients. METHODS: In a retrospective cross-sectional study, the use of parenteral antifungal medications among hospitalized patients was evaluated according to the prepared protocols adapted from the international guidelines. RESULTS: Among 151 patients, diagnostic approaches were appropriate and inappropriate in 90 and 61 patients respectively. Indications for antifungal drug administration were empiric therapy (80.1%) followed by targeted therapy (19.2%) and prophylaxis (0.7%). The indications were appropriate and inappropriate in 123 and 28 patients respectively. Selection of antifungals was appropriate in 117 patients, inappropriate in 16 patients, and was not assessable in other cases. The doses of antifungal medications were appropriate and inappropriate in 111 and 14 patients respectively. Among 151 patients, the duration of treatment was appropriate just in 33 cases. The techniques for antifungal administration were appropriate in 133 patients and inappropriate in 18 cases. CONCLUSIONS: Due to limited access to diagnostic tests, most parenteral antifungal medications were administered as empiric therapy. The diagnostic workups, treatment monitoring, and follow-up were inadequate in most patients. Development of local diagnostic and management protocols for invasive fungal infections and considering a stewardship program for antifungal medications are essential for each medical center.

Predictors of Non-invasive Ventilation Failure and Associated Factors Among the COVID-19 Patients Admitted to Intensive Care Unit.

Background: Non-invasive ventilation (NIV) is a method of oxygenation supply that eliminates the need for an endotracheal airway. Non-invasive ventilation failure is defined as the necessity for endotracheal intubation or death during the NIV trial. Objectives: This study aimed to identify the predictors and associated factors of NIV failure in coronavirus disease 2019 (COVID-19) patients admitted to an intensive care unit (ICU). Methods: This retrospective, longitudinal cohort study utilized electronic medical records of COVID-19 patients admitted to the ICU. A total of 150 patients were included in the study. Patient demographics, medical history, laboratory tests, partial pressure of carbon dioxide (PCO2), oxygen saturation (SpO2), heart rate, acidosis, consciousness, oxygenation, and respiratory rate (HACOR score), and the ratio of oxygen saturation (ROX) index (the SpO2/fraction of inspired oxygen [FIO2] to respiratory rate [SF] ratio) were recorded. Non-invasive ventilation failure was determined based on the need for endotracheal intubation or cardiac-respiratory arrest while on NIV. Results: Of 150 patients, 55.3% were male (mean age: 55.9 years), with an NIV failure rate of 67.3%, a mortality rate of 66.7%, and 3.3% of patients requiring tracheostomy after NIV failure. The ROX index consistently decreased over time, and an increase in the HACOR score and PCO2 after 6 hours of commencing NIV were the predictors of NIV failure. Additionally, higher levels of lactate dehydrogenase, lower SF ratios, and higher APACHE scores upon ICU admission were significantly associated with NIV failure. Notably, the erythrocyte sedimentation rate (ESR) as an inflammatory index, SF ratio upon ICU admission, HACOR score, ROX index, and PCO2 after 12 hours were significant predictors of in-hospital mortality in patients receiving NIV. Conclusions: The ROX index, HACOR scale, and PCO2 are significant predictors of both NIV failure and in-hospital mortality.

Simulation-based design optimization of a wrist exoskeleton.

Exoskeletons are widely used in the field of rehabilitation robotics. Upper limb exoskeletons (ULEs) can be very useful for patients with diminished ability to control their limbs in aiding activities of daily living (ADLs). The design of ULEs must account for a human's limitations and ability to work with an exoskeleton. It can typically be achieved by the involvement of vulnerable end-users in each design cycle. On the other hand, simulation-based design methods on a model with human-in-the-loop can limit the design cycles, thereby reducing research time and dependency on end users. This study makes it evident by using a case where the design of an exoskeleton wrist can be optimized with the usage of a torsional spring at the joint, that compensates for the required motor torque. Considering the human-in-the-loop system, the multibody modeling results show that the usage of a torsional spring in the joint can be useful in designing a lightweight and compact exoskeleton joint by downsizing the motor.Clinical Relevance- The proposed methodology of designing an upper-limb exoskeleton has a utility in limiting design cycles and making it both convenient and useful to assist users with severe impairment in ADLs.

Using workspace restrictiveness for adaptive velocity adjustment of assistive robots and upper limb exoskeletons.

Individuals with severe disabilities can benefit from assistive robotic systems (ARS) for performing activities of daily living. However, limited control interfaces are available for individuals who cannot use their hands for the control, and most of these interfaces require high effort to perform simple tasks. Therefore, autonomous and intelligent control strategies were proposed for assisting with the control in complex tasks. In this paper, we presented an autonomous and adaptive method for adjusting an assistive robot's velocity in different regions of its workspace and reducing the robot velocity where fine control is required. Two participants controlled a JACO assistive robot to grasp and lift a bottle with and without the velocity adjustment method. The task was performed 9.1% faster with velocity adjustment. Furthermore, analyzing the robot trajectory showed that the method recognized highly restrictive regions and reduced the robot end-effector velocity accordingly.Clinical relevance- The autonomous velocity adjustment method can ease the control of ARSs and improve their usability, leading to a higher quality of life for individuals with severe disabilities who can benefit from ARSs.