Related Experiment Videos
Fluctuations in cerebral oxygenation and blood volume during endotracheal suctioning in premature infants
A R Shah1, C D Kurth, S G Gwiazdowski
1Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia.
Insights
Endotracheal suctioning in infants causes temporary drops in blood oxygen and cerebral blood flow, leading to brain deoxygenation. Preoxygenation effectively prevents these adverse effects during mechanical ventilation.
Area of Science:
- Neonatal Physiology
- Pediatric Critical Care Medicine
- Neurovascular Regulation
Background:
- Endotracheal suctioning is a common procedure in mechanically ventilated infants.
- The effects of suctioning on cerebral circulation in preterm infants are not fully understood.
- Respiratory distress syndrome (RDS) is a significant condition in preterm neonates.
Purpose of the Study:
- To investigate the impact of endotracheal suctioning on cerebral circulation in preterm infants.
- To assess changes in brain intravascular hemoglobin saturation (tHbo2%) and cerebral blood volume (CBV) during suctioning.
- To determine if preoxygenation can mitigate the effects of suctioning on cerebral hemodynamics.
Main Methods:
- Monitoring of tHbo2%, CBV, and arterial hemoglobin saturation (Spo2) in 12 preterm infants (24-33 weeks GA) with RDS.
- Utilized dual-wavelength near-infrared spectroscopy for brain monitoring and pulse oximetry for Spo2.
- Repeated studies in 6 infants after preoxygenation to a baseline Spo2 of 100%.
Main Results:
- Suctioning caused a significant decrease in Spo2 (94% to 84%) and tHbo2%, with a concurrent increase in CBV (p<0.05).
- Cerebral desaturation and vasodilation occurred within 5 seconds of suctioning onset, with delayed brain reoxygenation (15 seconds post-reventilation).
- Preoxygenation prevented significant changes in Spo2, tHbo2%, and CBV during suctioning.
Conclusions:
- Endotracheal suctioning induces transient hypoxemia and cerebral vasodilation in preterm infants.
- These neurovascular effects are directly linked to hypoxemia caused by suctioning.
- Preoxygenation is a crucial intervention to prevent adverse cerebral circulatory effects during endotracheal suctioning in this population.
Abstract:
To investigate the effect that suctioning of the endotracheal tube has on the cerebral circulation, we monitored brain intravascular hemoglobin saturation (tHbo2%), cerebral blood volume (CBV), and arterial hemoglobin saturation (Spo2) during suctioning in 12 infants (24 to 33 weeks of gestational age) with respiratory distress syndrome treated with mechanical ventilation. The tHbo2% and CBV values were monitored over the forebrain by dual-wavelength near-infrared spectroscopy, and Spo2 was monitored by pulse oximetry of a finger. The monitored variables were stable during the baseline period. With suctioning, Spo2 decreased from 94% +/- 1% to 84% +/- 1%, tHbo2% decreased, and CBV increased (p less than 0.05). Desaturation in the arterial and cerebral circulations began within 5 seconds of the onset of suctioning. Arterial reoxygenation began with the onset of reventilation, whereas reoxygenation in the brain was delayed by 15 seconds. The Spo2, tHbo2%, and CBV values returned to baseline within 1 minute of reventilation. Studies were repeated in six of the infants after the fraction of inspired oxygen was increased to attain a baseline Spo2 of 100%. In the preoxygenated infants, tHbo2%, CBV, and Spo2 remained constant during suctioning. These studies confirm that endotracheal suctioning results in transient hypoxemia, and demonstrate that this is reflected in the brain by vasodilation and deoxygenation. These effects are preventable by preoxygenation before suctioning.