[Morphological aspects of diaphragm dysfunction in COVID-19-associated pneumonia]. / Morfologicheskie aspekty disfunktsii diafragmy pri COVID-19-assotsiirovannoi pnevmonii.

OBJECTIVE: To assess morphological changes in the diaphragm and phrenic nerve in patients who died from COVID-19. MATERIAL AND METHODS: In a case-control study, an analysis was made of autopsy material of the diaphragm and phrenic nerve of those who died from COVID-19 infection complicated by SARS-CoV-2-associated pneumonia, confirmed in vivo by the presence of SARS-CoV-2 RNA (Group 1, n=12), and those who died with a diagnosis of acute cerebrovascular accident of the ischemic type without parenchymal respiratory failure (Group 2, n=3). RESULTS: The main histopathological features in the diaphragm of the 1st group were the edema of the pericellular spaces of muscle fibers, edema of perivascular spaces, diapedese hemorrhages, plethora in arteriolas, in most veins and capillaries, red blood clots were revealed; in the diaphragmatic nerve - swelling of the perineral space, severe edema around the nerve fibers inside the nerve trunk. In the diaphragm of group 2, edema of pericellular spaces of muscle fibers and edema of perivascular spaces were less pronounced (p<0.001), hemorrhages were not determined; in the diaphragmatic nerve, moderate edema of the perineral space, mild swelling inside the nerve trunk around the nerve fibers was revealed (p<0.001). The glycogen content in the muscle cells of group 1 is significantly lower compared to group 2 (p<0.001). CONCLUSION: The study confirms the characteristic pathological picture of organ damage in COVID-19. However, the leading pathological mechanism of organ damage requires further investigation.

Metabolic therapy and its impact on lung respiratory function in patients with severe COVID-19

Background. Metabolic disorders, often detected in patients with severe COVID-19 infection, indicate the severity of the infection process and play an important role in the pathogenesis of the disease. Changes in muscle metabolism lead to weakness and reduced mobility of the diaphragm, which exacerbates the progression of respiratory failure. Aim. To evaluate the effect of a meglumine sodium succinate 1.5% solution on the dynamics of metabolic blood parameters and respiratory function of the lungs in patients with COVID-19. Material and methods. The observational prospective study included 105 patients with severe COVID-19 treated in the intensive care unit. As an infusion therapy, patients in the control group (n=54) received Ringer's solution, in the main group (n=51) — 1.5% solution of meglumine sodium succinate. Infusion therapy was carried out for 11 days. All patients underwent standard laboratory tests. Diaphragm mobility was assessed using an ultrasound scanner. Intergroup comparisons were performed using the Mann–Whitney test, and intragroup dynamics were assessed using the Kruskal–Wallis test. Results. Upon admission to the intensive care unit, in 36.2% of patients, the development of respiratory failure was accompanied by a decrease in the excursion of the right dome of the diaphragm to less than 1.7 cm, in 92.4% of patients — the development of hyperglycemia and hyperlactatemia. By the 11th day of ongoing treatment, hyperglycemia persisted in 16.7% of patients in the control group and 3.9% of patients in the main group, hyperlactatemia — in 53.7 and 9.8% of patients, respectively. Maintenance and then gradual restoration of diaphragm excursion in patients of the main group, a decrease in hypercapnia and a gradual increase in the pO2/FiO2 index were registered. Therapy with a solution of meglumine sodium succinate significantly reduced the duration of hospital treatment after transfer from the intensive care unit (p=0.007). Conclusion. The inclusion of a 1.5% solution of meglumine sodium succinate in the therapy of patients with severe COVID-19 can reduce the duration of metabolic disorders, which has a positive effect on the degree of respiratory dysfunction, diaphragmatic excursion depression and the treatment duration after transfer from the intensive care unit. © Eco-Vector, 2022. All rights reserved.

Diaphragm Function Parameters in Patients with Severe COVID-19

The aim of the study was to investigate the feasibility of predicting the need for mechanical ventilation in patients with severe COVID-19 disease using ultrasound assessment of diaphragm function. Material and methods. An open prospective pilot study included 60 patients diagnosed with the novel coronavirus infection, who, at the time of admission to the intensive care unit (NEWS score > 6), underwent ultrasound assessment of diaphragm excursion, thickness and the diaphragm thickening fraction. Group 1 (n=30) included patients who did not require mechanical ventilation, and group 2 (n=30) consisted of patients who were subsequently transferred to mechanical ventilation. Results. Patients in group 2 had significantly lower diaphragm function parameters (left excursion value (P<0.001), right excursion value (P<0.001), diaphragm thickness on inspiration (P=0.043), and thickening fraction (P<0.001) than patients in group 1. Conclusion. Decreased diaphragm excursion of less than 17.1 mm on the right side is a predictor of initiation of mechanical ventilation in patients with the COVID-19 infection (sensitivity 93.3%, specificity 76.7%). Morphological examination in deceased patients of group 2 revealed pericellular and perivascular edema, venular thrombosis, endoneurial edema, and sludge in the lumen of arterioles. © 2022, V.A. Negovsky Research Institute of General Reanimatology. All rights reserved.