The article summarizes the experience of leading professional communities in organizing the work of lung function laboratories during the COVID-19 pandemic. Recommendations on the choice of methods, indications for pulmonary function testing and infection control measures aimed at minimizing the risk of cross-infection of medical staff and patients are presented.

Improvements in equipment, new research studies and enhanced quality assurance approaches have led to the need to update the 2005 technical standards for spirometry. The article presents the main updates, developed by an international joint task force by the American Thoracic Society and the European Respiratory Society in 2019. The characteristics of acceptability, usability, and repeatability, criteria grading the quality of the test session, the choice of main reported values are described.

The present report introduces the electrophysiological conception of charging current in myocardium, alteration of ECG in different intensity of necrosis of myocardium, introduces parameter of topical diagnostics of focal changing of myocardium. Numerous clinical-ECG examples show specific ECG patterns in diagnostics of different types of myocardial infarction.

Objective: to assess the safety of indicators of electrical activity of the brain for the approach to the analysis of the basic neurophysiological mechanisms of the brain in patients after cardiac arrest.

Materials and methods: 52 patients were examined (age — 54,68 ± 19,33) after cardiac arrest. At the time of recording the electroencephalogram (EEG), the level of wakefulness of the examined patients on the Glasgow coma scale was in the range of 3 to 13 points. In 35 patients, EEG recording was performed starting from the first three days from the moment of cardiac arrest, in 17 patients — from the fourth to the 18th day. EEG was registered on electroencephalographs ‘Encephalan–EEGR–19/26’ by ‘Medikom MTD’, ‘Neuron-Spectrum–5/EP’ and ‘Neuron-Spectrum–65’ by ‘Neurosoft’ in accordance with the recommendations of the International Federation of Clinical Neurophysiologists (IFCN). The duration of a single EEG recordings lasted at least 30 min. To localize equivalent dipole sources of pathological activity we used the program ‘BrainLoc 6.0’, (Russia). In 19 patients EEG was recorded in dynamics from 2 to 8 times.

Results: all patients showed EEG changes of varying severity, which can be divided into three groups (according to the severity of changes in the EEG: moderate, severe and rough). In the group of patients with gross changes in EEG can be identified 4 variants: the first variant — absence of the alpha rhythm and the dominance of slow-wave fluctuations of the frequency spectrum; variant II — continuous generalized paroxysmal activity; variant III — phenomenon of ‘burst-suppression’; variant IV — a marked decrease in the amplitude of electrical activity of the brain to the level of 2–4 microvolt.

Conclusions: based on the dynamics of the EEG pattern in patients after cardiac arrest, it is possible to assume with a certain degree of probability the level of violations in the basic mechanisms of the brain.

Practical neurophysiology, as a rule, have limited knowledge of filtration in EEG. The author outlines the basic principles of filtering in electroencephalography, he clarifies the terminology, and explains the existing confusion in the concept of high and low frequency filters and analyzes the principles of selective filtering and possible errors in the interpretation of EEG with the wrong filtering mode selected.

Purpose: to evaluate the left ventricular (LV) echocardiographic indices of myocardial work using the LV pressure-strain loops method in healthy individuals.

Material and methods. The study included 50 healthy subjects (28 men, mean age: 44 ± 14 years). The inclusion criteria were the absence of any cardiovascular diseases and diabetes mellitus. After calculating global longitudinal strain (GLS) from speckle-tracking Echo and inserting values of brachial artery cuff blood pressure (BP), the vendor-specific module constructed non-invasive LV pressure-strain loops. The following parameters were calculated: global myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW), global work efficiency (GWE).

Results. The lowest values of GWI in men and women were 1382 mmHg% and 1821 mmHg%, the highest values were 2875 mmHg% and 2589 mmHg%, mean values were 2056 ± 326 mmHg% and 2109 ± 200 mmHg%, respectively. Mean values of GCW were 2292 ± 329 mmHg% in men and 2304 ± 211 mmHg% in women. The median and the highest value of GWW were 66 mmHg% and 313 mmHg% in men and 79,5 mmHg% and 172 mmHg% in women, respectively. The lowest value of GWE were 89% in men and 91% in women. GWI was significantly and naturally correlated only with systolic BP (r = 0,30, р = 0,03) and GLS (r = -0,72, р < 0,001). GCW was significantly correlated with systolic BP (r = 0,36, р = 0,01) and GLS (r = -0,72, р < 0,001) too, however, the negative relationship with the age of the patients was found (r = -0,27, р = 0,04). LV myocardial work indices did not significantly differ between men and women. Coefficients of variation for GWI, GCW and GWE did not exceed 10%, which is typical for good reproducible indices.

Conclusion. The study presents values of the echocardiographic LV myocardial work indices, obtained with help of the LV pressure-strain loops method in healthy individuals. The natural correlation of LV myocardial work indices with strain and blood pressure was demonstrated, as well as a dependence on the age of the subjects and good reproducibility.

The most rapid and complex ultrasound diagnosis is acute hemotamponade. The method of clinical management of the patient depends on the correct diagnosis: dynamic observation, pericardiocentesis or cardiac surgery.

Important for a doctor of ultrasound specialty to understand the technique of pericardiocentesis for proper ultrasound support of the puncture. Technically correct puncture almost immediately leads to improvement of the patient’s condition and normalization of hemodynamics.