Basic principles of mechanical ventilation in immature newborns and used ventilation modes

Overview

The chapter reflects, in a modified form, European recommendations that are standardized in the workplace in writing. Although the mechanisms of lung injury due to mechanical ventilation have universal effects on lung tissue, in premature newborns, they have specific impacts due to the fetal stage of lung development and frequently present fetal inflammatory responses. One of the fundamental principles of protecting immature lungs during mechanical ventilation is to maintain the lungs in a relatively homogeneous state without adverse effects on circulation. From this perspective, the parameters used can be divided into less and more injurious ones. Dynamic changes in lung volume are more injurious than static ones. During conventional mechanical ventilation modes, we adhere to the use of physiological tidal volumes and achieve their even distribution by optimizing the positive end-expiratory pressure level. At the same time, we prefer conventional modes that allow for the highest degree of synchronization with the patient's own breathing effort or even proportional support throughout the patient's entire respiratory cycle. For severe forms of respiratory failure and extremely premature infants < 26 weeks of gestation, we electively indicate high frequency oscillatory ventilation with the assumption of reducing the impact of shear forces in the canalicular-saccular developmental stage of the lungs. During mechanical ventilation, we prefer the prone position, which we consider a protective factor facilitating the even distribution of gas in the lungs. The chapter also deals with the use of inhaled nitric oxide in premature newborns with a history of severe oligohydramnios of various etiologies and maternal preeclampsia, where a reduction in endogenous nitric oxid can be expected in the adaptation phase after birth. The use of postnatal steroids, their choice, and dosage are related to the diagnosis and postnatal age of extremely premature newborns, not only on mechanical ventilation.

Keywords:

mechanical ventilation, lung injury, homogeneous ventilation, synchronized, proportional ventilation, inhaled nitric oxide, postnatal steroids