Resistance of pediatric and neonatal endotracheal tubes: Influence of flow rate, size, and shape

Abstract

Our results suggest that the use of a small-diameter, straight ETT will significantly increase the work of breathing.

Respiratory mechanics in ventilated preterm infants: early determinants and outcome

“…Previous studies showed that correction does not guarantee a better approximation of Rrs. 152,164 In contrast to our findings, Lischka and colleagues described significant associations between their score and Crs within 24 hours after birth. 154 Others described correlations between Giedion scores and parameters of lung function 43,124 , However, these studies were performed before exogenous surfactant therapy had been widely introduced.…”

“…Since endotracheal tube size substantially affects Rrs measurements during mechanical ventilation, 152,164 Rrs,neo was subsequently corrected for this effect by including tube diameter in all regression models. In these cases, we will refer to Rrs,neoC.…”

“…96,101,103 Unfortunately, according to experiments in rodents, the major effect of glucocorticoids on the pre-alveolarized postnatal lung is to decrease alveolar and vascular development. 164 Furthermore, postnatal corticosteroid therapy increases the risk of adverse long-term neurodevelopmental outcome. 95,266 As a consequence of these recent publications, the use of postnatal corticosteroid therapy has been dramatically restricted.…”

“…41 Presence of the endotracheal tube will add a (non-linear) resistance to the actual resistance of the airways or respiratory system. 152,164 To reduce this effect, routine suctioning, to clear secretions in the endotracheal tube and trachea before respiratory function testing, is required. 220 In infants, endotracheal tubes are uncuffed, increasing the risk of air leakage between tube and trachea.…”

Resistance of Colorimetric Carbon Dioxide Detectors Commonly Utilized in Neonates

“…Although the effects of artificial airways on spontaneous breathing during mechanical ventilation are well studied, their effects on work of breathing during bag mask ventilation or applied CPAP are not. 7 Resistance to flow is a critical factor when providing ventilation or CPAP to the spontaneously breathing infant. Imposed work of breathing can occur when a patient must breathe spontaneously through an artificial apparatus placed between the lungs and the air, such as ETTs, ETCO 2 detectors, flow sensors, and expiratory valves.…”