[Relations between several parameters of respiratory mechanics after radical correction of congenital heart defects]. / Sviaz' mezhdu nekotorymi pokazateliami mekhaniki dykhaniia posle radikal'noi korrektsii vrozhdennykh porokov serdtsa.

The results of this study are at variance with highly prevalent opinion that an increase in Vinsp leads to a parallel growth of Cst. A different degree of relationship between Vinsp and Cst was observed in the studied groups (from 0.33 to 0.92). These relationships in children with congenital heart disease are determined by the state of pulmonary circulation and lung parenchyma before surgery and after correction and depend on the form of the defect and patient's age. Such a variety of values is due to specificity of changes in the lungs depending on the pathomorphology of congenital heart disease and progress of these changes with age.

[The mechanical properties of the lungs in patients with congenital heart defects in the immediate postoperative period]. / Mekhanicheskie svoistva legkikh u bol'nykh s vrozhdennymi porokami serdtsa v blizhaishem posleoperatsionnom periode.

Static compliance and inspiratory resistance were assessed in 218 patients aged over 3 years after open-heart surgery for correction of congenital heart disease during the immediate postoperative period without complications. Cst in the immediate postoperative period in patients with Fallot's tetralogy, intraventricular septum defect, intraatrial septum defect, and incomplete form of atrioventricular communication was higher than in patients operated on for Fallot's tetralogy with a previous systemic-pulmonary anastomosis and pulmonary artery atresia, whereas Rinsp was virtually the same in all groups. Age-specific differences were noted. The data are recommended for use as reference values in stress.

[The use of a pressure-support ventilation regimen in the recovery of spontaneous respiration after heart operations]. / Ispol'zovanie rezhima ventiliatsii podderzhkoi davleniem pri vosstanovlenii spontannogo dykhaniia posle operatsii na serdtse.

Pressure-support ventilation (PSV) with supporting pressure (SP) levels 20, 15, 13, 10, and 8 mm H2O was used in 111 patients with congenital heart disease after open-heart surgery during transfer to spontaneous respiration. PSV was associated with a significant decrease of respiratory rate and increase of respiratory volume (RV) at high SP levels. Respiration in the PSV mode permits the patient to control the inspiration flow, duration of inspiration phase, and RV, thus improving the patient-device synchronization. Cardiac index (CI) was changing with decrease of SP from 20-15 to 13 mm H2O in patients with different diseases during high SP PSV. This is caused by changed pulmonary circulation (transfer to intraacinar type) which increased the negative correlation between CI and chosen SP. In addition, CI depends not only on RV, but on the status of lung parenchyma as well.

[The cardiac index dynamics of patients after the radical correction of tetralogy of Fallot depending on the level of the pressure-support ventilation (PSV) regimen]. / Dinamika serdechnogo indeksa u bol'nykh posle radikal'noi korrektsii tetraday Fallo v zavisimosti ot urovnia podderzhivaiushchego davleniia rezhima ventiliatsii PSV.

Seventeen patients were examined, reoperated on for correction of Fallot's tetralogy on the open heart after a previous aortopulmonary anastomosis. Pressure support ventilation (PSV) was used in all patients during transfer to spontaneous pressure, making use of different levels of pressure support (20, 15, 13, 10, and 8 mm H2O). Decrease of pressure support from 20-15 mm H2O to 13 mm H2O resulted in a sharp increase of cardiac index. We explain this phenomenon by a drastic increase of the respiratory volume during the use of high PSV levels (20-15 mm H2O), surpassing 1.5-2 times the physiological and age-specific norm; this leads to a sharp increase of the mean intrathoracic pressure, disturbing the cardiovascular function.