Chapter 14 - Oxygenation Instability in the Premature Infant

Abstract

Most premature infants present with significant oxygenation instability during the different phases of their respiratory course. This instability increases their susceptibility to episodes of hypoxemia and hyperoxemia. These episodes are more common in premature infants who remain on mechanical ventilation beyond the first weeks after birth and especially in those with evolving chronic lung disease. One of the most common mechanisms triggering episodic hypoxemia in these infants are spontaneous contractions of the abdominal musculature that splints the respiratory pump, resulting in periods of decreased lung volume, impaired lung mechanics, and hypoventilation. During routine care, intermittent hypoxemia is often followed by hyperoxemia induced by excessive oxygen supplementation in an attempt to correct the episodes or prevent their occurrence. Because of their frequency and persistence over days or weeks, episodes of intermittent hypoxemia may negatively affect long-term outcome. Thus it is critical to better understand the mechanisms and consequences of episodic hypoxemia to identify effective strategies to prevent them or attenuate their severity.