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Hard chromium coatings have a wide range of application due to their resistance to corrosion and wear. In the present work, chromium was commercially electroplated on 416 stainless steel. Thermal damage of the chromium coatings was investigated as a function of heating temperature and cooling rate. Specimens were heated to various temperatures and then cooled down either by air cooling or water quenching. An optical microscope was employed to assess the damage due to heating. No thermally-induced cracks were observed for specimens heated up to 600 °C. At 800 °C and higher, thermally-induced cracks were observed and increased with increasing temperature. Cracks generated during heating were likely due to thermal expansion coefficient mismatch between the coating and the substrate. Heating was found to significantly alter the residual stresses state in the coating. Residual stress increased when heated to 600 °C and dropped at 1000 °C. Spherical indentations were employed to evaluation the effects of heating on the mechanical damage of the coatings. Ring, cone, surface radial and radial bend cracks were observed on as-deposited and heated specimens up to 600 °C. Specimen heated up to 800 °C showed partially developed ring and radial bend cracks, while specimen heated up to 1000 °C displayed no indentation related cracks. • Beyond 600 °C, thermally-induced cracks were observed on the coatings. • Thermal cracks were likely caused by thermal expansion coefficient mismatch. • Coating hardness substantially dropped beyond 600 °C. • Heating increases residual stresses in coatings and thermal cracks release stresses. • Thermal cracks changed mechanical response of coatings to indentation loading. [ABSTRACT FROM AUTHOR]

Hard chromium coatings are widely used for high performance components due to their superior wear and corrosion resistance. In this study, 416 stainless steel bars were chromium electroplated commercially with different thickness. Mechanical properties and residual stress were measured using a nano-indentation system and X-ray diffraction, respectively. Image analysis technique was used to measure inherent crack density. Residual stress in the coating increases with increasing thickness leading to an increase in inherent crack density. An indentation study was carried out to investigate the mechanical damage of hard chromium coating as a function of thickness. Different failure modes were observed when hard chromium coatings were indented with a spherical indenter including Hertzian cone cracks, radial cracks, bend cracks, lateral cracks and coating delamination. Three thickness regions of distinctive cracking modes were identified. Thin coating region exhibited through-thickness Hertzian cracks. Hertzian and coating-bend rings, cone, surface radial cracks and coating bottom surface radial cracks were observed in intermediate coating region. This region exhibited highest cracking damage density. In thick coatings Hertzian cracks were observed. It was found that two factors affect the cracking damage: residual stress that increases with increasing thickness and bending stresses that decrease with increasing thickness. The resultant effect was maximized at intermediate coating thickness. [ABSTRACT FROM AUTHOR]

Objectives: To assess engagement in heart-healthy lifestyle practices and adherence to antihypertensive medications with knowledge of hypertension, for more effective blood pressure control. Methodology: It was a cross-sectional study involving adults of more than 18 years diagnosed with hypertension as study participants. Total sample size was 381. Assessment of medication adherence, and responses were calculated using Malaysian Medicine Adherence Score 8 (MALMAS 8) scale. The scoring system utilized in the MALMAS questionnaire, aligned with the MMAS-8, aids in categorizing participants based on their medication adherence levels. Data were collected using a pre-tested, self-administered questionnaire. The data were analysed using the statistical software for social sciences (SPSS26). Results: The prevalence of hypertension among the selected study participants was found to be 71%. High level of adherence was found in 33% of the participants. The medication adherence of the patient was significantly associated with gender (p<0.05). 27% of the study participants belong to the age group of 25-40 years. Around 63% of the females were having high adherence and this association was found to be statistically significant, (p value < 0.05.). There was no statistically significant association between participants' adherence to the age group they belong, marital status, educational level and their occupation. Conclusion: In conclusion, this cross-sectional study highlights the difficulty in adhering to treatment plans, with forgetfulness and trouble taking medications ranking as the biggest obstacles. Interestingly, adherence was higher in females than in males. Nevertheless, no statistically significant correlation was observed between medication adherence and other demographic variables, including age, income level, occupation, marital status, education, or occupation. [ABSTRACT FROM AUTHOR]

Background: Diabetes is a risk factor for infection with coronaviruses. This study describes the demographic, clinical data, and outcomes of critically ill patients with diabetes and Middle East Respiratory Syndrome (MERS).Methods: This retrospective cohort study was conducted at 14 hospitals in Saudi Arabia (September 2012-January 2018). We compared the demographic characteristics, underlying medical conditions, presenting symptoms and signs, management and clinical course, and outcomes of critically ill patients with MERS who had diabetes compared to those with no diabetes. Multivariable logistic regression analysis was performed to determine if diabetes was an independent predictor of 90-day mortality.Results: Of the 350 critically ill patients with MERS, 171 (48.9%) had diabetes. Patients with diabetes were more likely to be older, and have comorbid conditions, compared to patients with no diabetes. They were more likely to present with respiratory failure requiring intubation, vasopressors, and corticosteroids. The median time to clearance of MERS-CoV RNA was similar (23 days (Q1, Q3: 17, 36) in patients with diabetes and 21.0 days (Q1, Q3: 10, 33) in patients with no diabetes). Mortality at 90 days was higher in patients with diabetes (78.9% versus 54.7%, p < 0.0001). Multivariable regression analysis showed that diabetes was an independent risk factor for 90-day mortality (odds ratio, 2.09; 95% confidence interval, 1.18-3.72).Conclusions: Half of the critically ill patients with MERS have diabetes; which is associated with more severe disease. Diabetes is an independent predictor of mortality among critically patients with MERS. [ABSTRACT FROM AUTHOR]

Background The objective of this study was to evaluate the effect of ribavirin and recombinant interferon (RBV/rIFN) therapy on the outcomes of critically ill patients with Middle East respiratory syndrome (MERS), accounting for time-varying confounders. Methods This is a retrospective cohort study of critically ill patients with laboratory-confirmed MERS from 14 hospitals in Saudi Arabia diagnosed between September 2012 and January 2018. We evaluated the association of RBV/rIFN with 90-day mortality and MERS coronavirus (MERS-CoV) RNA clearance using marginal structural modeling to account for baseline and time-varying confounders. Results Of 349 MERS patients, 144 (41.3%) patients received RBV/rIFN (RBV and/or rIFN-α2a, rIFN-α2b, or rIFN-β1a; none received rIFN-β1b). RBV/rIFN was initiated at a median of 2 days (Q1, Q3: 1, 3 days) from intensive care unit admission. Crude 90-day mortality was higher in patients with RBV/rIFN compared to no RBV/rIFN (106/144 [73.6%] vs 126/205 [61.5%]; P =.02]. After adjusting for baseline and time-varying confounders using a marginal structural model, RBV/rIFN was not associated with changes in 90-day mortality (adjusted odds ratio, 1.03 [95% confidence interval {CI},.73–1.44]; P =.87) or with more rapid MERS-CoV RNA clearance (adjusted hazard ratio, 0.65 [95% CI,.30–1.44]; P =.29). Conclusions In this observational study, RBV/rIFN (RBV and/or rIFN-α2a, rIFN-α2b, or rIFN-β1a) therapy was commonly used in critically ill MERS patients but was not associated with reduction in 90-day mortality or in faster MERS-CoV RNA clearance. [ABSTRACT FROM AUTHOR]

Background: Noninvasive ventilation (NIV) has been used in patients with the Middle East respiratory syndrome (MERS) with acute hypoxemic respiratory failure, but the effectiveness of this approach has not been studied. Methods: Patients with MERS from 14 Saudi Arabian centers were included in this analysis. Patients who were initially managed with NIV were compared to patients who were managed only with invasive mechanical ventilation (invasive MV). Results: Of 302 MERS critically ill patients, NIV was used initially in 105 (35%) patients, whereas 197 (65%) patients were only managed with invasive MV. Patients who were managed with NIV initially had lower baseline SOFA score and less extensive infiltrates on chest radiograph compared with patients managed with invasive MV. The vast majority (92.4%) of patients who were managed initially with NIV required intubation and invasive mechanical ventilation, and were more likely to require inhaled nitric oxide compared to those who were managed initially with invasive MV. ICU and hospital length of stay were similar between NIV patients and invasive MV patients. The use of NIV was not independently associated with 90‐day mortality (propensity score‐adjusted odds ratio 0.61, 95% CI [0.23, 1.60] P = 0.27). Conclusions: In patients with MERS and acute hypoxemic respiratory failure, NIV failure was very high. The use of NIV was not associated with improved outcomes. [ABSTRACT FROM AUTHOR]

NASAM (National Approach to Standardize and Improve Mechanical Ventilation) is a national collaborative quality improvement project in Saudi Arabia. It aims to improve the care of mechanically ventilated patients by implementing evidence-based practices with the goal of reducing the rate of ventilator-associated events and therefore reducing mortality, mechanical ventilation duration and intensive care unit (ICU) length of stay. The project plans to extend the implementation to a total of 100 ICUs in collaboration with multiple health systems across the country. As of March 22, 2019, a total of 78 ICUs have registered from 6 different health sectors, 48 hospitals, and 27 cities. The leadership support in all health sectors for NASAM speaks of the commitment to improve the care of mechanically ventilated patients across the kingdom. [ABSTRACT FROM AUTHOR]

• More than one-third of critically ill patients with Middle East Respiratory Syndrome Coronavirus (MERS-CoV) received empiric therapy with macrolides. • Macrolide therapy is not significantly associated with a reduction in 90-day mortality of critically ill patients with MERS-CoV. • Macrolide therapy is not significantly associated with improvement in MERS-CoV RNA clearance of critically ill patients with MERS-CoV. Macrolides have been reported to be associated with improved outcomes in patients with viral pneumonia related to influenza and other viruses, possibly because of their immune-modulatory effects. Macrolides have frequently been used in patients with Middle East Respiratory Syndrome (MERS). This study investigated the association of macrolides with 90-day mortality and MERS coronavirus (CoV) RNA clearance in critically ill patients with MERS. This retrospective analysis of a multicenter cohort database included 14 tertiary-care hospitals in five cities in Saudi Arabia. Multivariate logistic-regression analysis was used to determine the association of macrolide therapy with 90-day mortality, and the Cox-proportional hazard model to determine the association of macrolide therapy with MERS-CoV RNA clearance. Of 349 critically ill MERS patients, 136 (39%) received macrolide therapy. Azithromycin was most commonly used (97/136; 71.3%). Macrolide therapy was commonly started before the patient arrived in the intensive care unit (ICU) (51/136; 37.5%), or on day1 in ICU (53/136; 39%). On admission to ICU, the baseline characteristics of patients who received and did not receive macrolides were similar, including demographic data and sequential organ failure assessment score. However, patients who received macrolides were more likely to be admitted with community-acquired MERS (P = 0.02). Macrolide therapy was not independently associated with a significant difference in 90-day mortality (adjusted odds ratio [OR]: 0.84; 95% confidence interval [CI] :0.47–1.51; P = 0.56) or MERS-CoV RNA clearance (adjusted HR: 0.88; 95% CI:0.47–1.64; P = 0.68). These findings indicate that macrolide therapy is not associated with a reduction in 90-day mortality or improvement in MERS-CoV RNA clearance. [ABSTRACT FROM AUTHOR]

Background: Middle East Respiratory Syndrome Coronavirus (MERS-CoV) leads to healthcare-associated transmission to patients and healthcare workers with potentially fatal outcomes. Aim: We aimed to describe the clinical course and functional outcomes of critically ill healthcare workers (HCWs) with MERS. Methods: Data on HCWs was extracted from a multi-center retrospective cohort study on 330 critically ill patients with MERS admitted between (9/2012–9/2015). Baseline demographics, interventions and outcomes were recorded and compared between survivors and non-survivors. Survivors were approached with questionnaires to elucidate their functional outcomes using Karnofsky Performance Status Scale. Findings: Thirty-Two HCWs met the inclusion criteria. Comorbidities were recorded in 34% (11/32) HCW. Death resulted in 8/32 (25%) HCWs including all 5 HCWs with chronic renal impairment at baseline. Non-surviving HCW had lower PaO2/FiO2 ratios 63.5 (57, 116.2) vs 148 (84, 194.3), p = 0.043, and received more ECMO therapy compared to survivors, 9/32 (28%) vs 4/24 (16.7%) respectively (p = 0.02).Thirteen of the surviving (13/24) HCWs responded to the questionnaire. Two HCWs confirmed functional limitations. Median number of days from hospital discharge until the questionnaires were filled was 580 (95% CI 568, 723.5) days. Conclusion: Approximately 10% of critically ill patients with MERS were HCWs. Hospital mortality rate was substantial (25%). Patients with chronic renal impairment represented a particularly high-risk group that should receive extra caution during suspected or confirmed MERS cases clinical care assignment and during outbreaks. Long-term repercussions of critical illness due to MERS on HCWs in particular, and patients in general, remain unknown and should be investigated in larger studies. [ABSTRACT FROM AUTHOR]

Background: It had been more than 5 years since the first case of Middle East Respiratory Syndrome coronavirus infection (MERS-CoV) was recorded, but no specific treatment has been investigated in randomized clinical trials. Results from in vitro and animal studies suggest that a combination of lopinavir/ritonavir and interferon-β1b (IFN-β1b) may be effective against MERS-CoV. The aim of this study is to investigate the efficacy of treatment with a combination of lopinavir/ritonavir and recombinant IFN-β1b provided with standard supportive care, compared to treatment with placebo provided with standard supportive care in patients with laboratory-confirmed MERS requiring hospital admission.Methods: The protocol is prepared in accordance with the SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) guidelines. Hospitalized adult patients with laboratory-confirmed MERS will be enrolled in this recursive, two-stage, group sequential, multicenter, placebo-controlled, double-blind randomized controlled trial. The trial is initially designed to include 2 two-stage components. The first two-stage component is designed to adjust sample size and determine futility stopping, but not efficacy stopping. The second two-stage component is designed to determine efficacy stopping and possibly readjustment of sample size. The primary outcome is 90-day mortality.Discussion: This will be the first randomized controlled trial of a potential treatment for MERS. The study is sponsored by King Abdullah International Medical Research Center, Riyadh, Saudi Arabia. Enrollment for this study began in November 2016, and has enrolled thirteen patients as of Jan 24-2018.Trial Registration: ClinicalTrials.gov, ID: NCT02845843 . Registered on 27 July 2016. [ABSTRACT FROM AUTHOR]

Objectives: To describe patient characteristics, clinical manifestations, disease course including viral replication patterns, and outcomes of critically ill patients with severe acute respiratory infection from the Middle East respiratory syndrome and to compare these features with patients with severe acute respiratory infection due to other etiologies.Design: Retrospective cohort study.Setting: Patients admitted to ICUs in 14 Saudi Arabian hospitals.Patients: Critically ill patients with laboratory-confirmed Middle East respiratory syndrome severe acute respiratory infection (n = 330) admitted between September 2012 and October 2015 were compared to consecutive critically ill patients with community-acquired severe acute respiratory infection of non-Middle East respiratory syndrome etiology (non-Middle East respiratory syndrome severe acute respiratory infection) (n = 222).Interventions: None.Measurements and Main Results: Although Middle East respiratory syndrome severe acute respiratory infection patients were younger than those with non-Middle East respiratory syndrome severe acute respiratory infection (median [quartile 1, quartile 3] 58 yr [44, 69] vs 70 [52, 78]; p < 0.001), clinical presentations and comorbidities overlapped substantially. Patients with Middle East respiratory syndrome severe acute respiratory infection had more severe hypoxemic respiratory failure (PaO2/FIO2: 106 [66, 160] vs 176 [104, 252]; p < 0.001) and more frequent nonrespiratory organ failure (nonrespiratory Sequential Organ Failure Assessment score: 6 [4, 9] vs 5 [3, 7]; p = 0.002), thus required more frequently invasive mechanical ventilation (85.2% vs 73.0%; p < 0.001), oxygen rescue therapies (extracorporeal membrane oxygenation 5.8% vs 0.9%; p = 0.003), vasopressor support (79.4% vs 55.0%; p < 0.001), and renal replacement therapy (48.8% vs 22.1%; p < 0.001). After adjustment for potential confounding factors, Middle East respiratory syndrome was independently associated with death compared to non-Middle East respiratory syndrome severe acute respiratory infection (adjusted odds ratio, 5.87; 95% CI, 4.02-8.56; p < 0.001).Conclusions: Substantial overlap exists in the clinical presentation and comorbidities among patients with Middle East respiratory syndrome severe acute respiratory infection from other etiologies; therefore, a high index of suspicion combined with diagnostic testing is essential component of severe acute respiratory infection investigation for at-risk patients. The lack of distinguishing clinical features, the need to rely on real-time reverse transcription polymerase chain reaction from respiratory samples, variability in viral shedding duration, lack of effective therapy, and high mortality represent substantial clinical challenges and help guide ongoing clinical research efforts. [ABSTRACT FROM AUTHOR]