Subjects and Methods. The study involved 35 vascular surgery patients of varying degrees of cardiological risk. Blood specimens were collected from each patient at 3 time-points: 1. prior to surgery (NT-proBNP₁), 2 — after the procedure (NT-proBNP₂), 3 — before the discharge from the hospital (NT-proBNP₃). Each specimen was split into equal aliquots for biomarker quantification using two different techniques (ELISA using domestic reagents — for the 1st series of analyses, and ICLA using an imported kit — for the 2nd series). Perioperative cardiovascular complications were recorded. The consistency of the measurement results obtained by two different methods was evaluated using the Bland–Altman technique. A discrimination ability of independent variables in relation to a binary dependent variable was studied using ROC analysis.

Results. In the 1^st series, ranges of the biomarker were as follows: NT-proBNP₁ — 24–774 pg/ml, NT-proBNP₂ — 41.2–889.1 pg/ml, NT-proBNP₃ — 39.3–1013.3 pg/ml. In the 2^nd series, NT-proBNP₁ was 31.2–2087.0 pg/ml, NT-proBNP₂ — 32.5–3754.0 pg/ml, NT-proBNP₃ — 34.1–2728.0 pg/ml. In the Bland–Altman analysis, 97.03% of the values fell within the lower and upper limits of consistency (±1.96 SD of the average difference), which indicated comparability of the results in the series, but the values of NT-proBNP in the 1^st series were lower than in the 2^nd ones. Cardiovascular complications were registered in 3 (8.5%) patients. In the 1^st series, NT-proBNP₁ > 218 pg/ml predicted cardiovascular complications with a sensitivity of 66.7% and a specificity of 81.3% (AUC 0.844, 95% CI 0.681–0.944, P = 0.0003). In the 2^nd series, NT-proBNP₁ > 315 pg/ml predicted cardiovascular complications with a sensitivity of 66.7% and a specificity of 75.0% (AUC 0.828, 95% CI 0.663–0.934, P = 0.001).

Conclusion. The domestic ELISA kit for solid-phase enzyme immunoassay proved its clinical informativeness for quantitation of NT-proBNP demonstrating its value for diagnostic and prognostic purposes, or scientific studies. The novel domestic technique provides consistently reproducible results, although with lower reference values as compared to the standard immunochemiluminescence assay.

Incentive spirometry is one of the most common methods used for respiratory rehabilitation in the early period after cardiac surgery. Inspiratory capacity values, obtained by a patient using spirometer, are not reliably trusted.

Objectives. To compare volumetric parameters measured with incentive spirometer and results obtained with bedside ultrasound-based spirometer to assure the feasibility of the use of incentive spirometry to assess the inspiratory capacity and effectiveness of postoperative respiratory rehabilitation.

Materials and methods. The study included 50 patients after elective cardiac surgery. Pulmonary rehabilitation involved the use of various respiratory therapy methods. Spirography was performed before and after each session. Both approaches were used simultaneously to obtain the spirometry maximum inspiratory capacity (SMIC) with a bedside ultrasonic spirography and maximum inspiratory capacity (MIC) index using an incentive spirometer. Patient’s discomfort and adverse events during the procedures were recorded.

Results. The absolute values of the MIC measured before and after each session by the two methods were dissimilar, however, the average increment values (6) did not show statistically significant differences. The correlation analysis revealed a strong positive statistically significant relationship between 6 SMIC and 6 MIC (R = 0.74 before the session, R = 0.79 after the session, R = 0.77 across the whole data set, P < 0.01), also consistent with the Bland–Altman analysis, evidencing that more than 95% of all values fell within ± 1.96 SD of the mean difference. The inspiratory spirometry method showed good diagnostic accuracy (sensitivity 87%, specificity 85%, area under the curve (AUC) 0.8 (95% CI: [0.76; 0.83]), P < 0.001). Refusals of procedure were more often documented with ultrasonic spirography.

Conclusion. The increment in the inspiratory capacity index measured with incentive spirometer shows good agreement with ultrasonic spirography measurements. Therefore, incentive spirometry can be reliably used to assess the effectiveness of respiratory rehabilitation interventions in cardiac surgery patients during early postoperative period.

Materials and methods. This study analyzed the results of treatment of 62 patients with severe COVID-19 in the intensive care unit using selective hemoadsorption of cytokines. All patients with severe COVID-19 were admitted to the intensive care unit within 14 days from the disease onset were subdivided into two groups. Group 1 patients (n=32) received on a top of standard treatment the hemoperfusion (HP) procedure for 4 hours, for 2–3 days in a row, using a cytokine sorption column composed of mesoporous styrene-divinilbenzen copolymer matrix. Group 2 patients were not subjected to extracorporeal blood purification. All patients received IL-6 inhibitors at a baseline in accordance to the temporary guidelines. We evaluated factors of unfavorable outcomes by analyzing changes in biochemical markers of systemic inflammatory response and mortality rates in patients of both groups.

Results. Initiation of HP later than 10 days from NCI onset (P < 0.001), length of stay in the ICU, extent of lung damage (P = 0.036) and the SOFA (Sequential Organ Failure Assessment) score (P = 0.009) were the most powerful predictors of unfavorable outcome. Levels of systemic inflammatory response markers (interleukin- 6, CRP, D-dimer) in both groups did not significantly affect the survival rates and length of hospital stay (P > 0.05). HP group demonstrated better survival (P < 0.05). Mean hospital stay was 31 and 27 days, ICU stay — 11 and 8 days for Groups 1 and 2, respectively (P < 0.05).

Conclusion. Treatment of severe COVID-19 patients with HP using novel domestic hemosorbent composed of styrene-divinilbenzen copolymer matrix resulted in decrease in CRP levels on the first day after application and, with early onset, contributed to a significant increase in survival and decreased hospital and ICU stay. Additional studies are warranted to clarify the optimal timing of the initiation of HP in severe COVID-19 patients.

Fundamental research in recent years has allowed us to reassess the molecular and cellular mechanisms of cardiac ontogenesis and its repair after damage. The epicardium, the outer, tightly adjoining layer of the cardiac wall formed by epicardial mesothelial cells, collagen and elastic fibers, has gained special relevance as an important participant of reparative processes. Better insight into poorly understood epicardial function is challenged due to anatomical issues and lack of relevant cellular models.

The aim of this study was to develop a spheroid 3D model of the epicardial microenvironment and determine responses of spheroids to hypoxia.

Materials and methods. Spheroids were harvested in V-shaped culture dishes with a low adhesion coating. Immunofluorescent staining of cryosections, histological methods and real-time PCR were used for characterization of cultured spheroids.

Results. We demonstrated that cultivation of cells under low adhesion conditions in V-shaped culture dishes resulted in the formation of spheroids with an average size of 136+21 µm and cell viability rates of over 98%. The cells in the spheroids cultured under normoxic conditions formed tight junctions and were characterized by a low level of proliferation and the ability to synthesize extracellular matrix proteins. Under hypoxia cells in the spheroids showed partial loss of intercellular contacts, acquired a spindle shape, started to express HIF1a, SNAIL, COL1Al and accumulate collagen. All these features demonstrated the activation of mesothelial(endothelial)-mesenchymal transition strongly resembling epicardial cellular responses to ischemia in vivo.

Conclusion. An epicardial spheroid cell culture model suitable for study cellular responses to hypoxic environment was developed. This model can be used to clarify mechanisms regulating epicardial microenvironment and test new targeted candidate drugs.

Aim. This review aims to inform physicians of different specialties (anesthesiologists, intensivists, neurologists, neurosurgeons, oncologists) about the diagnostic capabilities of microwave radiothermometry, which enables to identify and analyze features of alterations of cerebral temperature in brain damage.

The review displays a critical analysis of 80 recent Russian and foreign open access publications found by keywords.

The review presents major clinical features and pathophysiological mechanisms of cerebral thermal balance disruptions in brain lesions. Slow responsiveness and vulnerability of cerebral thermal homeostasis regulation mechanisms that underlie development of different temperature heterogeneity levels in the cerebral cortex in healthy brain and brain lesions are highlighted. The authors postulate their concept about the critical role of hyperthermia in the pathogenesis of brain damage and disruption of interconnections in the global central regulation system. A body of evidence explaining direct association between the depth of consciousness impairment and degree of cerebral cortex temperature heterogeneity manifestation is presented. It is emphasized that a significant increase in temperature heterogeneity with areas of focal hyperthermia accompanies an acute period of ischemic stroke, while in post-comatose state usually associated with prolonged impairment of consciousness, the temperature heterogeneity significantly subsides. It has been suggested that lowering of an increased and rising of the reduced temperature heterogeneity, for example by using temperature exposure, can improve altered level of consciousness in patients with brain damage. The diagnostic capabilities of various technologies used for cerebral temperature measurement, including microwave radiothermometry (MWR), are evaluated. Data on high accuracy of MWR in measurement of the cerebral cortex temperature in comparison with invasive methods are presented.

Conclusion. In healthy individuals MWR revealed a distinct daily rhythmic changes of the cerebral cortex temperature, and badly violated circadian rhythms in patients with brain lesions. Since MWR is an easy-toperform, non-invasive and objective diagnostic tool, it is feasible to use this technology to detect latent cerebral hyperthermia and assess the level of temperature heterogeneity disruption, as well as to study the circadian rhythm of temperature changes.

Impairment of higher mental functions can complicate the course of the postoperative period even after short and minimally invasive, including laparoscopic, surgical procedures. Postoperative cognitive dysfunction significantly challenges patients’ quality of life, negating real success of surgical intervention and anesthetic support. In some cases, early postoperative cognitive dysfunction may be one of the main predictors of persistent cognitive impairment.

The purpose of the review. To contemplate etiology, pathogenesis and the current perspective of postoperative cognitive dysfunction.

We analyzed 96 publications in various databases (PubMed, Medline, RSCI and others), including 67 papers published over the past 5 years.

The review provides an overview of current definitions and classification of postoperative cognitive dysfunction, data on the prevalence, polyethyology and risk factors, potential impact of the type of anesthesia and surgical intervention on the development of postoperative cognitive dysfunction. Various pathogenetic mechanisms of higher mental functions impairment alongside with available effective pharmacotherapies to correct them were considered.

Conclusion. Numerous adverse factors of the perioperative period, such as neurotoxic effects of general anesthetics, neuroinflammation in response to operational stress and surgical trauma, impaired autoregulation of the cerebral blood flow, imperfect oxygen homeostasis, interactions of neurotransmitter, etc., can potentially cause postoperative cognitive dysfunction. Further deeper insights into etiology and pathogenesis of early postoperative cognitive dysfunction are relevant and necessary to improve prevention strategies and identify most effective pharmacotherapies to correct such disorders.

The aim of the study. To study the achievability and contingency to maintain an effective plasma lithium concentration in the perioperative period in patients undergoing carotid endarterectomy (CEAE) with oral intake of lithium carbonate pills.

Materials and methods. It was a prospective study, as a preparatory stage of the multicenter «BINOS» (NCT05126238) RCT. The sample included 15 patients undergoing elective CEAE. In the course of this study, patients were administered oral lithium carbonate, 900 mg per day during 4 perioperative days: two days before the procedure, in the day of surgery and in the 1st postoperative day. Plasma lithium concentration was monitored every 24 hours during all 4 days from the onset of treatment.

Results. Increased plasma lithium concentrations were found in blood samples taken at 48 hours (0.68 mmol/l [0.53–0.84, P = 0.004) and 72 hours (0.68 mmol/l [0.62–0.90, P < 0.001), as compared with the initial values (0.14 mmol/l [0.11–0.17).While during the period between 48 and 72 hours from the onset of treatment the plasma lithium concentration remained in the therapeutic range (0.4–1.2 mmol/l) in 100% of patients.

Conclusion. Oral intake of lithium carbonate pills at a dose of 900 mg/day during 2 preoperative days provided an effective and safe plasma lithium concentration in 100% of patients enrolled in the study.

Determination of brain dying means reversible or irreversible injury to the brain, including the brainstem. Current guidelines rely on clinical examination including the proof of coma, absent brain stem reflexes, and apnoea test. Neurophysiological testing using electroencephalography and evoked potentials — somatosensory evoked potentials and brainstem auditory evoked potential could have been helpful in the final diagnostic brain death conclusion, but the diagnostic accuracy of these methods in the last years has revealed controversies. Here, we present data on quantitative EEG signal evaluation (qEEG) by a 3-dimensional brain mapping (3D BM) as developing tool to clarify whether the transverse and anterior posterior coherences such as connectivity indices may demonstrate connection in transversal or anterior posterior dimensions with «wavelet transformation» and if the 3D BM visualization of the of representative EEG signals may improve informative value of EEG signals quantification when evaluating the brain dying.

The purpose of our work is to provide an update on the evidence and controversies on the use of EEG for determining brain dying and raise discussion on EEG applications to improve the transplantation program.

Results. We analyzed the EEG records of 10 patients admitted for cardiopulmonary resuscitation (CPR) during September, 2017 — August, 2018. Data from one patient, ŽM, 33 years old, after haemorrhagic shock (August 2018) were analyzed in details. Quantitative EEG dynamics by images and clinical course of brain dying were monitored prior and after the amantadine sulfate intravenous administration for brain revival. Data demonstrated the ability of brain to survive; the cause of final brain death was heart failure.

Conclusion. Data confirm the hope for survival of the brain in a coma and demonstrate brain capability to keep functionally optimal state as a potential for a good social adaptation.