[Frequency analysis of the ECG of patients with acute respiratory failure]

The author presented the results of an amplitude-frequency analysis of ECG of 64 patients with different forms of acute respiratory insufficiency (101 investigations). Artificial pulmonary ventilation was performed in all the patients, using positive pressure at the end of expiration in 86% of the patients. ECG was recorded in 3 orthogonal deflections after Frank. Spectral analysis was performed using a spectrobiograph CB-1-ts-02. 5-7 cardiocycles were analyzed in each deflection with the processing of 2 ECG segments: the QRS complex, S-T segment and T wave. The gaseous composition of the arterial, capillary and mixed venous blood was determined in all the patients. The deterioration of indices of the blood gaseous composition was accompanied by an increase in Am spectrum power values in the X, Y and Z leads against a background of a rise of the proportion of high frequency components in the ECG spectrum of these leads. Later on in the approximation of the blood gaseous composition values to the critical ones, Am values were lower than those in the control group which was in line with a decrease in the proportion of high frequency components in the ECG signal.