Current options in the management of apnea of prematurity

Abstract

Apnea of prematurity (AOP) is a common problem that affects premature infants and, to a lesser degree, term infants. Apnea of prematurity appears to be due to immaturity of the infant's neurologic and respiratory systems. Apnea of prematurity is a diagnosis of exclusion that can be made only when other possible infectious, cardiologic, physiologic, and metabolic causes of apnea have been ruled out. The fundamental principles for managing apnea of prematurity include monitoring the infant closely while instituting supportive care measures such as tactile stimulation, continuous positive airway pressure, or mechanical ventilation. When necessary, pharmacologic therapy may be used to stimulate breathing. The first-line agents of choice for the management of AOP are the methylxanthines. And, for second-line therapy, a switch to a different class of agent, such as the respiratory stimulant doxapram, is an option. Of the methylxanthines, theophylline is the most extensively used. However, a review of the literature suggests that caffeine citrate may be the agent of choice for AOP. Comparative clinical studies have demonstrated that caffeine is at least as effective as theophylline, has a longer half-life, is associated with fewer adverse events, and, in addition, has a greater ease of administration. Caffeine stimulates the respiratory and central nervous systems more effectively and penetrates into the cerebrospinal fluid more readily than theophylline. In addition, because of stable plasma levels, caffeine has a wide therapeutic margin and few side effects. In contrast, theophylline plasma levels may fluctuate widely, which necessitates frequent monitoring and has a higher incidence of adverse events than caffeine. Before the FDA approval of caffeine citrate (Cafcit) for administration either intravenously and/or orally, caffeine preparations were "homemade." A few studies suggest that use of pharmacotherapy to treat AOP is not generally associated with long-term sequelae, although more data are needed before this can be definitively concluded.