A comparison of the hemodynamic and respiratory effects of surfactant instillation during interrupted ventilation versus noninterrupted ventilation in rabbits with severe respiratory failure.

The purpose of this study was to evaluate whether avoiding interruption of ventilation during surfactant instillation improves the effects on lung function and surfactant distribution and whether it prevents the adverse effects on blood pressure and cerebral blood flow. The study was performed using rabbits with severe respiratory failure induced by lung lavages. These rabbits were randomized to 99mTc-Nanocoll labeled surfactant instillation through a side lumen of the endotracheal tube without interrupting ventilation or instillation during a short interruption of ventilation.

Surfactant nebulization versus instillation during high frequency ventilation in surfactant-deficient rabbits.

Surfactant nebulization improves lung function at low alveolar doses of surfactant. However, efficiency of nebulization is low, and lung deposition seems to depend on lung aeration. High frequency ventilation (HFV) has been shown to improve lung aeration.

Surfactant nebulisation prevents the adverse effects of surfactant therapy on blood pressure and cerebral blood flow in rabbits with severe respiratory failure.

Objective: Surfactant replacement therapy for the neonatal respiratory distress syndrome has shown beneficial effects on lung function and survival. Recently, rapid fluctuations of haemodynamics and cerebral perfusion following surfactant instillation have been described and an association with the development of intraventricular haemorrhage has been proposed. Therefore, alternative methods of surfactant therapy that reduce the effects on cerebral perfusion have to be explored.

Surfactant nebulisation: lung function, surfactant distribution and pulmonary blood flow distribution in lung lavaged rabbits.

Objective: Surfactant nebulisation is a promising alternative to surfactant instillation in newborns with the respiratory distress syndrome. Although less surfactant is deposited in the lung, it improves gas exchange, probably due to a superior distribution. We hypothesize that a more uniform distribution of nebulised surfactant results in a more uniform pulmonary blood flow and consequently a more efficient gas exchange.

Surfactant nebulisation: safety, efficiency and influence on surface lowering properties and biochemical composition.

Objective: The objectives of this study were, to select a nebuliser first, that operates safely in a neonatal ventilator setting and, second, that is most efficient. Thirdly, we studied the particle sizes of the surfactant aerosol. Fourthly, we studied where the nebulised surfactant is deposited in the tubing system of the ventilator.