This study compared survival outcomes between intensive care unit (ICU) patients receiving enteral nutrition (EN) and parenteral nutrition (PN) with vasopressor support, explored risk factors affecting clinical outcomes and established an evaluation model. Data from 1046 ICU patients receiving vasopressor therapy within 24 h from 2008 to 2019 were collected. Patients receiving nutritional therapy within 3 d of ICU admission were divided into EN or PN (including PN+EN) groups. Cox analysis and regression were used to determine relevant factors and establish a nomogram for predicting survival. The 28-d survival rate was significantly better in the EN group compared with the PN/PN+EN group. Risk factors included age, peripheral capillary oxygen saturation, red cell distribution width, international normalised ratio, potassium level, mean corpuscular Hg, myocardial infarction, liver disease, cancer status and nutritional status. The nomogram showed good predictive performance. In ICU patients receiving vasopressor drugs, patients receiving EN had a better survival rate than PN. Our nomogram had favourable predictive value for 28-d survival in patients. However, it needs further validation in prospective trials.

Our study aimed to systematically analyse the risk factors of coronavirus disease 2019 (COVID-19) patients with severe disease. An electronic search in eight databases to identify studies describing severe or critically ill COVID-19 patients from 1 January 2020 to 3 April 2020. In the end, we meta-analysed 40 studies involving 5872 COVID-19 patients. The average age was higher in severe COVID-19 patients (weighted mean difference; WMD = 10.69, 95%CI 7.83–13.54). Patients with severe disease showed significantly lower platelet count (WMD = −18.63, 95%CI −30.86 to −6.40) and lymphocyte count (WMD = −0.35, 95%CI −0.41 to −0.30) but higher C-reactive protein (CRP; WMD = 42.7, 95%CI 31.12–54.28), lactate dehydrogenase (LDH; WMD = 137.4, 95%CI 105.5–169.3), white blood cell count（WBC), procalcitonin（PCT）, D-dimer, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and creatinine（Cr）. Similarly, patients who died showed significantly higher WBC, D-dimer, ALT, AST and Cr but similar platelet count and LDH as patients who survived. These results indicate that older age, low platelet count, lymphopenia, elevated levels of LDH, ALT, AST, PCT, Cr and D-dimer are associated with severity of COVID-19 and thus could be used as early identification or even prediction of disease progression.

Muscle tissue serves as a protein reservoir which is mobilized to meet the specific metabolic needs associated with various catabolic conditions in human subjects, such as trauma and critical illness. Glutathione is one of the most abundant short-chain peptides and a major source of non-protein thiol in the body, and tissue glutathione concentration is related to its oxidative capacity. Skeletal muscle is relatively unique with respect to a variety of metabolic properties, such as oxidative potential, patterns of amino acid utilization, and antioxidant enzyme activity. The glutathione concentration is not influenced by food intake, or by food deprivation. Moreover, there is no diurnal variation on muscle glutathione levels. Following elective surgery the muscle concentration of GSH (the reduced form) decreases by 40 % 24 h post-operatively, while the concentration of GSSG (the oxidized form) remains unaltered. During critical illness a similar decrease in the GSH concentration is seen, but in addition a change in the redox status indicative of an elevated GSSG level occurs. Furthermore, correlations between the concentrations of glutamine as well as glutamate and GSH exist in these patients. From available evidence accumulated it is clear that glutathione plays a pivotal role in the maintenance of the intracellular redox status, the antioxidant vitamin levels, and the antioxidant enzyme functions under various metabolic conditions. The effectiveness of glutathione protection in the individual tissue depends on the tissue concentration of glutathione as well as the capacity of the tissue to import GSH and to export GSSG. The mechanisms by which catabolism regulates tissue glutathione levels and the enzyme activities associated with the γ-glutamyl cycle are not completely understood and further studies need to be conducted.