[Optimization of artificial respiration parameters in patients with acute pulmonary parenchymal damage syndrome]

The relationship between the mean pressure in the trachea, generated in mechanical ventilation of the lungs (Ptr.m), and normal arterial oxygenation is linear in ventilated patients with severe bilateral acute parenchymatous damage to the lungs. Under conditions of mechanical ventilation of the lungs (MVL) with regulated volume, constant end-expiratory pressure (PEEP) and inspiratory pause (eIP) are effective methods for regulating Ptr.m. However, the efficacy of regulating Ptr.m by PEEP and IF for each clinical case is different. The algorithm of using PEEP and IF for optimizing the respiratory pattern in this category of patients is not clear, too. The results indicate that optimization of MVL with controlled volume should be started with selecting the optimal level of PEEP for each patient. The level of Ptr.m should not be increased immediately at by of prolonging eIP, because the probability of compromising the hemodynamics is higher in such a case than the probability of improving blood oxygenation. Only after selecting the optimal PEEP is it permissible to try to improve arterial oxygenation by prolonging xx, because under such conditions the efficacy of prolonged inspiration is notably increased. Our data indicate that eIP no higher than 30% of the respiratory cycle (inspiration/expiration = 1.5/1) is the optimal. A further increase of eIP gives rise to a tendency towards decrease of arterial oxygenation and oxygen transport to tissues.