Cerebral oxygenation and hemodynamics during open and closed endotracheal suctioning in ventilated preterm infants

Objective To investigate the effects of open, closed and sham endotracheal suctioning on changes in cerebral oxygenation and hemodynamics and some selected physiological variables in ventilated preterm infants. Methods In ten ventilated preterm infants open, closed and sham endotracheal suctioning were performed in random order with an interval between interventions of 1 h. Changes in cerebral concentration of oxyhemoglobin and deoxyhemoglobin and changes in cerebral blood volume were measured using near infra-red spectrophotometry; changes in cerebral blood flow velocity in the internal carotid artery were measured using pulsed Doppler ultrasound. Results Closed endotracheal suctioning resulted in the same decrease of cerebral oxyhemoglobin concentration and a smaller increase of deoxyhemoglobin concentration as compared to open and sham endotracheal suctioning, but the same fluctuations of cerebral blood volume and cerebral blood flow velocity still occurred. The use of the closed endotracheal suctioning device resulted in increased cerebral blood flow velocity and cerebral blood volume due to hypercapnia. Conclusions Closed endotracheal suctioning in ventilated preterm infants results in a smaller decrease of cerebral oxygen supply but the same fluctuation in cerebral hemodynamics when compared to open and sham endotracheal suctioning. The large dead space of the suctioning device facilitates hypercapnia resulting in cerebral hyperperfusion.