A comprehensive review on hydrogen production, storage, and applications.

The transformation from combustion-based to renewable energy technologies is of paramount importance due to the rapid depletion of fossil fuels and the dramatic increase in atmospheric CO2 levels resulting from growing global energy demands. To achieve the Paris Agreement's long-term goal of carbon neutrality by 2050, the full implementation of clean and sustainable energy sources is essential. Consequently, there is an urgent demand for zero or low-carbon fuels with high energy density that can produce electricity and heat, power vehicles, and support global trade. This review presents the global motivation to reduce carbon dioxide by utilizing hydrogen technology, which is key to meeting future energy demands. It discusses the basic properties of hydrogen and its application in both prototype and large-scale efficient technologies. Hydrogen is a clean fuel and a versatile energy carrier; when used in fuel cells or combustion devices, the final product is water vapor. Hydrogen gas production methods are reviewed across renewable and non-renewable sources, with reaction processes categorized as green, blue, grey, black, pink, and turquoise, depending on the reaction pathway and CO2 emissions management. This review covers the applications of hydrogen technology in petroleum refining, chemical and metrological production, hydrogen fuel cell electric vehicles (HFCEVs), backup power generation, and its use in transportation, space, and aeronautics. It assesses physical and material-based hydrogen storage methods, evaluating their feasibility, performance, and safety, and comparing HFCEVs with battery and gasoline vehicles from environmental and economic perspectives. Finally, the prospects and challenges associated with hydrogen production, handling, storage, transportation, and safety are also discussed.

Metabolic profile and gene expression pattern of cytokines and antioxidants markers during different physiological stages in Barki ewes.

BACKGROUND: In livestock, identifying the physiological and reproductive stages is valuable in guiding management decisions related to nutrition, veterinary procedures, and breeding programs. To achieve this goal, a cohort of Barki ewes in this research underwent observation across three pivotal physiological conditions: pre-pregnancy, late pregnancy, and early lactation. Blood samples were collected to investigate the changes in serum metabolic profile as well as gene expression pattern of cytokines and antioxidants markers during these stages. RESULTS: Our results showed that during late pregnancy, there was a significant (P < 0.05) increase in red blood cells (11.9 ± 0.5 1012/L), hemoglobin (10.8 ± 0.4 g/dl) and neutrophils count (7 ± 0.1 109/L) with significant decrease (P < 0.05) of total white blood cell count (9.1 ± 0.05 109/L). The packed cell volume (%) and monocyte count showed a significant (P < 0.05) decrease during both late pregnancy and early lactation stages. The serum concentrations of glucose, cholesterol, GSH, GPx, SOD and catalase displayed significant (P < 0.05) decrease during late pregnancy and early-lactation. Notably, during late pregnancy, there was a significant (P < 0.05) increase in the serum concentrations of albumin, globulin, urea, IGF-1, and malondialdehyde with significant decrease (P < 0.05) of total protein (4.9 ± 0.08 g/dl). Additionally, during early lactation, there was a significant (P < 0.05) increase in the serum levels of non-esterified fatty acids, triiodothyronine (T3), and thyroxin (T4). The gene expression profiles of cytokines (IL-4, IL-6, IL-8, and NFKB) were decreased in the ewes during late pregnancy compared to pre-pregnant and early lactation stages. In addition, the expression profile of antioxidant genes (SOD, CAT, GPX, and Nrf2) was significantly upsurged in the non-pregnant ewes compared to late pregnancy and early lactation ones. CONCLUSIONS: The results concluded that different physiological status significantly affects the blood metabolic profile and gene expression pattern in Barki sheep. Our findings can be helpful in monitoring animal health and applying in breeding programs of Barki sheep under harsh environmental conditions.

Microbial signature inferred from genomic breeding selection on milk urea concentration and its relation to proxies of nitrogen-utilization efficiency in Holsteins.

Increasing the nitrogen-utilization efficiency (NUE) of dairy cows by breeding selection would offer advantages from nutritional, environmental, and economic perspectives. Because data collection of NUE phenotypes is not feasible in large cow cohorts, the cow individual milk urea concentration (MU) has been suggested as an indicator trait. Considering the symbiotic interplay between dairy cows and their rumen microbiome, individual MU was thought to be influenced by host genetics and by the rumen microbiome, the latter in turn being partly attributed to host genetics. To enhance our knowledge of MU as an indicator trait for NUE, we aimed to identify differential abundant rumen microbial genera between Holstein cows with divergent genomic breeding values for MU (GBVMU; GBVHMU vs. GBVLMU, where H and L indicate high and low MU phenotypes, respectively). The microbial genera identified were further investigated for their correlations with MU and 7 additional NUE-associated traits in urine, milk, and feces in 358 lactating Holsteins. Statistical analysis of microbial 16S rRNA amplicon sequencing data revealed significantly higher abundances of the ureolytic genus Succinivibrionaceae UCG-002 in GBVLMU cows, whereas GBVHMU animals hosted higher abundances of Clostridia unclassified and Desulfovibrio. The entire discriminating ruminal signature of 24 microbial taxa included a further 3 genera of the Lachnospiraceae family that revealed significant correlations to MU values and were therefore proposed as considerable players in the GBVMU-microbiome-MU axis. The significant correlations of Prevotellaceae UCG-003, Anaerovibrio, Blautia, and Butyrivibrio abundances with MU measurements, milk nitrogen, and N content in feces suggested their contribution to genetically determined N-utilization in Holstein cows. The microbial genera identified might be considered for future breeding programs to enhance NUE in dairy herds.

Irradiation impact on biological activities of Anthraquinone pigment produced from Talaromyces purpureogenus and its evaluation, characterization and application in beef burger as natural preservative.

BACKGROUND: The demand for natural coloring and preservative agents in food industry is increasing day by day as a result of awareness of the negative health effects of synthetic color preservatives. Consumers want foods with less processing, a longer shelf life, and clear labels that list only natural ingredients and food additives with familiar names that promote good health. In order to meet consumer demands and regain consumers' confidence in the safety of food products, the food industry was compelled to search for natural alternatives with strong antibacterial and antioxidant properties. Therefore, the objective of this study was to produce a microbial pigment that not only serve as food coloring agents but also provide health advantages owing to their bioactivities. Additionally, the potential use of anthraquinone pigment (AQP) as a natural food preservative compared to gamma irradiation was also examined to extend the shelf life of the beef burger and improve its hygienic quality. RESULTS: This study used Talaromyces purpureogenus AUMC2603 to produce the red natural pigment, which was identified as an anthraquinone pigment (AQP). According to the results, gamma (γ) radiation had no significant effect on AQP's antibacterial properties. However, it has a negative, considerable effect on antioxidant activity, where a large dose of γ-ray may change the antioxidant components and lessen the AQP's capacity to scavenge free radicals. Additionally, the γ ray-treated AQP had a strong cytotoxic activity in relation to a high γ-ray dose. As a result, it is suggested that AQP-containing foods should not be irradiated. The extracted AQP was applied as a food additive to improve the quality and increase the shelf life of beef burgers. Significant antibacterial and antioxidant action has been shown at 2% (w/v) AQP. The findings demonstrated that the treatment of beef burger with AQP decreased the initial total bacterial count and psychrophilic bacteria and extended the shelf-life of beef burger in comparison to the control (beef burger with no addition of AQP, butylated hydroxytoluene (BHT) or gamma radiation treatment). On the other hand, there was no substantial difference in the overall amount of mold and yeast or coliform at zero time. According to sensory characteristics, beef burgers had a shelf life of 6 days for controls and 9, 12, and 15 days for AQP-treated samples at 0.5, 1 and 2%, respectively, compared to γ- irradiated samples, 9 and 21 days, at 3 and 5 Kilo Gray (KGy), respectively. CONCLUSIONS: This research provides a natural red pigment from Talaromyces purpureogenus with potent biological activities as antimicrobials and antioxidants to be applied as coloring, additive, and preservative agent in the food industry. Also, the tested pigment offers a powerful alternative to gamma irradiation for extending the shelf life of food products.

Optic Nerve Sheath Diameter Ultrasound for Raised Intracranial Pressure: A Literature Review and Meta-analysis of its Diagnostic Accuracy.

Optic nerve sheath diameter (ONSD) ultrasound is becoming increasingly more popular for estimating raised intracranial pressure (ICP). We performed a systematic review and analysis of the diagnostic accuracy of ONSD when compared to the standard invasive ICP measurement. METHOD: We performed a systematic search of PUBMED and EMBASE for studies including adult patients with suspected elevated ICP and comparing sonographic ONSD measurement to a standard invasive method. Quality of studies was assessed using the QUADAS-2 tool by two independent authors. We used a bivariate model of random effects to summarize pooled sensitivity, specificity, and diagnostic odds ratio (DOR). Heterogeneity was investigated by meta-regression and sub-group analyses. RESULTS: We included 18 prospective studies (16 studies including 619 patients for primary outcome). Only one study was of low quality, and there was no apparent publication bias. Pooled sensitivity was 0.9 [95% confidence intervals (CI): 0.85-0.94], specificity was 0.85 (95% CI: 0.8-0.89), and DOR was 46.7 (95% CI: 26.2-83.2) with partial evidence of heterogeneity. The Area-Under-the-Curve of the summary Receiver-Operator-Curve was 0.93 (95% CI: 0.91-0.95, P < .05). No covariates were significant in the meta-regression. Subgroup analysis of severe traumatic brain injury and parenchymal ICP found no heterogeneity. ICP and ONSD had a correlation coefficient of 0.7 (95% CI: 0.63-0.76, P < .05). CONCLUSION: ONSD is a useful adjunct in ICP evaluation but is currently not a replacement for invasive methods where they are feasible.

Reverse Triggering Dyssynchrony 24 h after Initiation of Mechanical Ventilation.

BACKGROUND: Reverse triggering is a delayed asynchronous contraction of the diaphragm triggered by passive insufflation by the ventilator in sedated mechanically ventilated patients. The incidence of reverse triggering is unknown. This study aimed at determining the incidence of reverse triggering in critically ill patients under controlled ventilation. METHODS: In this ancillary study, patients were continuously monitored with a catheter measuring the electrical activity of the diaphragm. A method for automatic detection of reverse triggering using electrical activity of the diaphragm was developed in a derivation sample and validated in a subsequent sample. The authors assessed the predictive value of the software. In 39 recently intubated patients under assist-control ventilation, a 1-h recording obtained 24 h after intubation was used to determine the primary outcome of the study. The authors also compared patients' demographics, sedation depth, ventilation settings, and time to transition to assisted ventilation or extubation according to the median rate of reverse triggering. RESULTS: The positive and negative predictive value of the software for detecting reverse triggering were 0.74 (95% CI, 0.67 to 0.81) and 0.97 (95% CI, 0.96 to 0.98). Using a threshold of 1 µV of electrical activity to define diaphragm activation, median reverse triggering rate was 8% (range, 0.1 to 75), with 44% (17 of 39) of patients having greater than or equal to 10% of breaths with reverse triggering. Using a threshold of 3 µV, 26% (10 of 39) of patients had greater than or equal to 10% reverse triggering. Patients with more reverse triggering were more likely to progress to an assisted mode or extubation within the following 24 h (12 of 39 [68%]) vs. 7 of 20 [35%]; P = 0.039). CONCLUSIONS: Reverse triggering detection based on electrical activity of the diaphragm suggests that this asynchrony is highly prevalent at 24 h after intubation under assist-control ventilation. Reverse triggering seems to occur during the transition phase between deep sedation and the onset of patient triggering.

Duration of diaphragmatic inactivity after endotracheal intubation of critically ill patients.

BACKGROUND: In patients intubated for mechanical ventilation, prolonged diaphragm inactivity could lead to weakness and poor outcome. Time to resume a minimal diaphragm activity may be related to sedation practice and patient severity. METHODS: Prospective observational study in critically ill patients. Diaphragm electrical activity (EAdi) was continuously recorded after intubation looking for resumption of a minimal level of diaphragm activity (beginning of the first 24 h period with median EAdi > 7 µV, a threshold based on literature and correlations with diaphragm thickening fraction). Recordings were collected until full spontaneous breathing, extubation, death or 120 h. A 1 h waveform recording was collected daily to identify reverse triggering. RESULTS: Seventy-five patients were enrolled and 69 analyzed (mean age ± standard deviation 63 ± 16 years). Reasons for ventilation were respiratory (55%), hemodynamic (19%) and neurologic (20%). Eight catheter disconnections occurred. The median time for resumption of EAdi was 22 h (interquartile range 0-50 h); 35/69 (51%) of patients resumed activity within 24 h while 4 had no recovery after 5 days. Late recovery was associated with use of sedative agents, cumulative doses of propofol and fentanyl, controlled ventilation and age (older patients receiving less sedation). Severity of illness, oxygenation, renal and hepatic function, reason for intubation were not associated with EAdi resumption. At least 20% of patients initiated EAdi with reverse triggering. CONCLUSION: Low levels of diaphragm electrical activity are common in the early course of mechanical ventilation: 50% of patients do not recover diaphragmatic activity within one day. Sedatives are the main factors accounting for this delay independently from lung or general severity. Trial Registration ClinicalTrials.gov (NCT02434016). Registered on April 27, 2015. First patients enrolled June 2015.

Potential for Lung Recruitment Estimated by the Recruitment-to-Inflation Ratio in Acute Respiratory Distress Syndrome. A Clinical Trial.

Rationale: Response to positive end-expiratory pressure (PEEP) in acute respiratory distress syndrome depends on recruitability. We propose a bedside approach to estimate recruitability accounting for the presence of complete airway closure.Objectives: To validate a single-breath method for measuring recruited volume and test whether it differentiates patients with different responses to PEEP.Methods: Patients with acute respiratory distress syndrome were ventilated at 15 and 5 cm H2O of PEEP. Multiple pressure-volume curves were compared with a single-breath technique. Abruptly releasing PEEP (from 15 to 5 cm H2O) increases expired volume: the difference between this volume and the volume predicted by compliance at low PEEP (or above airway opening pressure) estimated the recruited volume by PEEP. This recruited volume divided by the effective pressure change gave the compliance of the recruited lung; the ratio of this compliance to the compliance at low PEEP gave the recruitment-to-inflation ratio. Response to PEEP was compared between high and low recruiters based on this ratio.Measurements and Main Results: Forty-five patients were enrolled. Four patients had airway closure higher than high PEEP, and thus recruitment could not be assessed. In others, recruited volume measured by the experimental and the reference methods were strongly correlated (R2 = 0.798; P < 0.0001) with small bias (-21 ml). The recruitment-to-inflation ratio (median, 0.5; range, 0-2.0) correlated with both oxygenation at low PEEP and the oxygenation response; at PEEP 15, high recruiters had better oxygenation (P = 0.004), whereas low recruiters experienced lower systolic arterial pressure (P = 0.008).Conclusions: A single-breath method quantifies recruited volume. The recruitment-to-inflation ratio might help to characterize lung recruitability at the bedside.Clinical trial registered with www.clinicaltrials.gov (NCT02457741).

Implementing a bedside assessment of respiratory mechanics in patients with acute respiratory distress syndrome.

BACKGROUND: Despite their potential interest for clinical management, measurements of respiratory mechanics in patients with acute respiratory distress syndrome (ARDS) are seldom performed in routine practice. We introduced a systematic assessment of respiratory mechanics in our clinical practice. After the first year of clinical use, we retrospectively assessed whether these measurements had any influence on clinical management and physiological parameters associated with clinical outcomes by comparing their value before and after performing the test. METHODS: The respiratory mechanics assessment constituted a set of bedside measurements to determine passive lung and chest wall mechanics, response to positive end-expiratory pressure, and alveolar derecruitment. It was obtained early after ARDS diagnosis. The results were provided to the clinical team to be used at their own discretion. We compared ventilator settings and physiological variables before and after the test. The physiological endpoints were oxygenation index, dead space, and plateau and driving pressures. RESULTS: Sixty-one consecutive patients with ARDS were enrolled. Esophageal pressure was measured in 53 patients (86.9%). In 41 patients (67.2%), ventilator settings were changed after the measurements, often by reducing positive end-expiratory pressure or by switching pressure-targeted mode to volume-targeted mode. Following changes, the oxygenation index, airway plateau, and driving pressures were significantly improved, whereas the dead-space fraction remained unchanged. The oxygenation index continued to improve in the next 48 h. CONCLUSIONS: Implementing a systematic respiratory mechanics test leads to frequent individual adaptations of ventilator settings and allows improvement in oxygenation indexes and reduction of the risk of overdistention at the same time. TRIAL REGISTRATION: The present study involves data from our ongoing registry for respiratory mechanics (ClinicalTrials.gov identifier: NCT02623192 . Registered 30 July 2015).

Trials directly comparing alternative spontaneous breathing trial techniques: a systematic review and meta-analysis.

BACKGROUND: The effect of alternative spontaneous breathing trial (SBT) techniques on extubation success and other clinically important outcomes is uncertain. METHODS: We searched MEDLINE, EMBASE, CENTRAL, CINAHL, Evidence-Based Medicine Reviews, Ovid Health Star, proceedings of five conferences (1990-2016), and reference lists for randomized trials comparing SBT techniques in intubated adults or children. Primary outcomes were initial SBT success, extubation success, or reintubation. Two reviewers independently screened citations, assessed trial quality, and abstracted data. RESULTS: We identified 31 trials (n = 3541 patients). Moderate-quality evidence showed that patients undergoing pressure support (PS) compared with T-piece SBTs (nine trials, n = 1901) were as likely to pass an initial SBT (risk ratio (RR) 1.00, 95% confidence interval (CI) 0.89-1.11; I 2 = 77%) but more likely to be ultimately extubated successfully (RR 1.06, 95% CI 1.02-1.10; 11 trials, n = 1904; I 2 = 0%). Exclusion of one trial with inconsistent results for SBT and extubation outcomes suggested that PS (vs T-piece) SBTs also improved initial SBT success (RR 1.06, 95% CI 1.01-1.12; I 2 = 0%). Limited data suggest that automatic tube compensation plus continuous positive airway pressure (CPAP) vs CPAP alone or PS increase SBT but not extubation success. CONCLUSIONS: Patients undergoing PS (vs T-piece) SBTs appear to be 6% (95% CI 2-10%) more likely to be extubated successfully and, if the results of an outlier trial are excluded, 6% (95% CI 1-12%) more likely to pass an SBT. Future trials should investigate patients for whom SBT and extubation outcomes are uncertain and compare techniques that maximize differences in support.

Genome-Wide Association Analysis of Semen Characteristics in Piétrain Boars.

Since artificial insemination is common practice in pig breeding, the quality and persistence of the semen are decisive for the usability of individual boars. In the current study, genome-wide association analyses were performed to investigate the genetic variability underlying phenotypic variations in semen characteristics. These traits comprise sperm morphology and sperm motility under different temporal and thermal storage conditions, in addition to standard semen quality parameters. Two consecutive samples of the fourth and fifth ejaculates from the same boar were comprehensively analyzed in a genotyped Piétrain boar population. A total of 13 genomic regions on different chromosomes were identified that contain single-nucleotide polymorphisms significantly associated with these traits. Subsequent analysis of the genomic regions revealed candidate genes described to be involved in spermatogenesis, such as FOXL3, GPER1, PDGFA, PRKAR1B, SNRK, SUN1, and TSPO, and sperm motility, including ARRDC4, CEP78, DNAAF5, and GPER1. Some of these genes were also associated with male fertility or infertility in mammals (e.g., CEP78, GPER1). The analyses based on these laboriously determined and valuable phenotypes contribute to a better understanding of the genetic background of male fertility traits in pigs and could prospectively contribute to the improvement of sperm quality through breeding approaches.

Electrical and dielectric characteristics of molybdenum dioxide nanoparticles for high-performance electrocatalysis.

As an attempt to improve the catalytic processes in different electrochemical systems, molybdenum dioxide nanoparticles were prepared using the hydrothermal method, and their electrical and dielectric properties were investigated. The nanoparticles were polycrystalline with an orthorhombic structure. AC electrical transport properties of the pressed disc were conducted over a temperature range of 303-423 K and a frequency range of 42-5 × 106 Hz. The AC conductivity follows Jonscher's universal dynamic law, and it has been determined that correlated barrier hopping (CBH) is the primary conduction mechanism. The maximum barrier height (WM) was found to be 0.92 eV. The low activation energy showed that hopping conduction is the dominant mechanism of transporting current. The dielectric parameters were analyzed using both complex permittivity and complex electric modulus, with a focus on how they vary with temperature and frequency. At relatively high temperatures and low frequencies, the dielectric parameters showed a high-frequency dependence. The dielectric modulus showed that relaxation peaks move towards lower frequency when temperature increases. The dielectric relaxation activation energy, Δ Eω was determined to be 0.31 eV.

Intraventricular Tigecycline as a Last Resort Therapy in a Patient with Difficult-to-Treat Healthcare-Associated Acinetobacter baumannii Ventriculitis: a Case Report.

Healthcare-associated ventriculitis and meningitis is a common complication in patients who suffer from head trauma or have undergone a neurosurgery. Healthcare-associated ventriculitis and meningitis is associated with significant morbidity and mortality. Complications of healthcare-associated ventriculitis and meningitis include persistent vegetative state, moderate and severe disability, and death. Acinetobacter baumannii is the causative pathogen in 3.6-11.2% of cases of healthcare-associated ventriculitis and meningitis. Cases of difficult-to-treat healthcare-associated A. baumannii ventriculitis and meningitis are being reported more frequently. However, in most of these cases, a combination of intravenous (IV) and intraventricular (IVT)/intrathecal colistin achieves good therapeutic outcome. This report describes a clinical case of difficult-to-treat healthcare-associated A. baumannii ventriculitis. The A. baumannii strain was sensitive to colistin and trimethoprim-sulfamethoxazole, intermediate to tigecycline, and resistant to other antibiotics. While colistin was the drug of choice in our case, the patient developed anaphylactoid reaction during the IV administration of the loading dose of colistin, which mandated us to discontinue colistin and complicated the treatment of our patient. The patient did not respond to a combination of IV antibiotics that included meropenem, trimethoprim-sulfamethoxazole, and tigecycline. However, when IVT tigecycline was added as a last-resort therapeutic option, the patient's ventriculitis dramatically improved, and the patient was discharged from the hospital. Physicians who treat patients with healthcare-associated A. baumannii ventriculitis might resort to IVT tigecycline when they run out of therapeutic options.

Tocilizumab in the treatment of rapidly evolving COVID-19 pneumonia and multifaceted critical illness: A retrospective case series.

BACKGROUND: COVID-19 associated critical illness characterized by rapidly evolving acute respiratory failure (ARF) can develop, especially on the grounds of hyperinflammation. AIM AND METHODS: A case-series of 61 patients admitted to our intensive care unit (ICU) between August 12 and September 12, 2020 with confirmed COVID-19 pneumonia and rapidly evolving ARF requiring oxygen support therapy and/or mechanical ventilation was retrospectively analyzed. We examined whether intravenous administration of tocilizumab, a monoclonal interleukin-6 receptor antibody, was associated with improved outcome. All patients received empiric antivirals, dexamethasone 6 mg/day for 7 days, antibiotics, and prophylactic anticoagulation. Tocilizumab was administered at a dosage of 8 mg/kg [two consecutive intravenous infusions 12 h apart]. Outcome measures such as mortality on day-14, ICU length of stay, and rate of nosocomial acquired bacterial infections were also analyzed. Results: Patients were males (88.2%) aged 51 [interquartile range (IQR): 42.5-58.75)], with admission Acute Physiology and Chronic Health Evaluation (APACHE) 4 score of 53 (IQR: 37.75-72.5), and had more than one comorbidity (62.3%). On admission, twenty nine patients (47.5%) were mechanically ventilated, and thirty two patients (52.5%) were receiving oxygen therapy. No serious adverse effects due to tocilizumab therapy were recorded. However, twelve patients (19.6%) developed nosocomial acquired infections. ICU length of stay was 13 (IQR: 9-17) days, and mortality on day-14 was 24.6%. Six patients were shifted to other hospitals but were followed-up. The overall mortality on day-30 was 31.1%. Non-mechanically ventilated patients had higher survival rates compared to mechanically ventilated patients although results were not significant [hazards ratio = 2.6 (95% confidence intervals: 0.9-7.7), p = 0.08]. Tocilizumab did not affect the mortality of critically ill COVID-19 patients. CONCLUSION: Tocilizumab could be an adjunct safe therapy in rapidly evolving COVID-19 pneumonia and associated critical illness.

Impact on Efficacy and Safety of Hydrocortisone in Sepsis and Septic Shock - A Systematic Literature Review and Meta-analysis.

BACKGROUND: Sepsis and septic shock are major causes of morbidity and mortality worldwide, associated with a high economic and social burden on healthcare systems and communities, yet with few definite treatment modalities. The efficacy of steroids in the management of sepsis or septic shock remains a controversy and subject of investigation due to their theoretical beneficial effects. METHODS: This was a systematic literature review and meta-analysis on randomized controlled trials of hydrocortisone usage in sepsis or septic shock as of 2000, following the GRADE methodology, considering a primary outcome of 28 day all-cause mortality. RESULTS: Ten randomized control trials were included in the review, 9 of which reported 28 day mortality either as a primary or secondary outcome. Relative risk of dying at 28 days was 0.93 in favor of hydrocortisone (95% CI: 0.86-1.01; P = 0.056). Other secondary outcomes of the review were similarly statistically insignificant. The quality of evidence was graded as very low to low. CONCLUSION: Hydrocortisone, when used in sepsis or septic shock, in critically ill adult patients showed a statistically insignificant trend towards decreasing 28 day all-cause mortality. This warrants consideration of clinical significance for each patient individually.

Improved Outcomes following the Establishment of a Neurocritical Care Unit in Saudi Arabia.

BACKGROUND: Dedicated neurocritical care units have dramatically improved the management and outcome following brain injury worldwide. AIM: This is the first study in the Middle East to evaluate the clinical impact of a neurocritical care unit (NCCU) launched within the diverse clinical setting of a polyvalent intensive care unit (ICU). DESIGN AND METHODS: A retrospective before and after cohort study comparing the outcomes of neurologically injured patients. Group one met criteria for NCCU admission but were admitted to the general ICU as the NCCU was not yet operational (group 1). Group two were subsequently admitted thereafter to the NCCU once it had opened (group 2). The primary outcome was all-cause ICU and hospital mortality. Secondary outcomes were ICU length of stay (LOS), predictors of ICU and hospital discharge, ICU discharge Glasgow Coma Scale (GCS), frequency of tracheostomies, ICP monitoring, and operative interventions. RESULTS: Admission to NCCU was a significant predictor of increased hospital discharge with an odds ratio of 2.3 (95% CI: 1.3-4.1; p=0.005). Group 2 (n = 208 patients) compared to Group 1 (n = 364 patients) had a significantly lower ICU LOS (15 versus 21.4 days). Group 2 also had lower ICU and hospital mortality rates (5.3% versus 10.2% and 9.1% versus 19.5%, respectively; all p < 0.05). Group 2 patients had higher discharge GCS and underwent fewer tracheostomies but more interventional procedures (all p < 0.05). CONCLUSION: Admission to NCCU, within a polyvalent Middle Eastern ICU, was associated with significantly decreased mortality and increased hospital discharge.

New Optic Nerve Sonography Quality Criteria in the Diagnostic Evaluation of Traumatic Brain Injury.

BACKGROUND: New sonographic quality criteria to optimize optic nerve sheath diameter (ONSD) measurements were suggested. The latter were correlated to elevated intracranial pressure (ICP) in traumatic brain injury (TBI). AIM: We investigated whether ONSD measurements were correlated to simultaneous ICP measurements in severe TBI. METHODS: Forty patients with severe TBI (Marshall Scale ≥II and GCS ≤8) participated in the study. All patients had an intraparenchymal ICP catheter inserted, while ONSD was measured bilaterally, upon admission and over the next 48 hours, based on the new sonographic criteria. A total of 400 ONSD measurements were performed, while mean ONSD values of both eyes were used in the analysis. RESULTS: ONSD measurements were strongly correlated to ICP values (r=0.74, p < 0.0001). Receiver operator curve (ROC) analysis revealed that the ONSD cutoff value for predicting elevated ICP was 6.4 mm when using the mean of both eyes (AUC = 0.88, 95% CI = 0.80 to 0.95; sensitivity = 85.3%, specificity = 82.6%). Linear regression analysis nested models revealed that sex (p=0.006) and height (p=0.04) were significant predictors of ONSD values. CONCLUSION: When applying the new sonographic quality criteria, ONSD is strongly correlated to ICP in severe TBI. Whether to use such criteria to monitor ONSD as a proxy for ICP trend in TBI remains to be further explored.