![]() However, stimulation of these same receptors in the premature infant results in apnea. For example, stimulation of laryngeal receptors in the adult results in coughing. The premature infant also manifests an immature response to peripheral vagal stimulation. This is due to immaturity of brainstem control of central respiratory drive. In other words, there is no signal to breathe being transmitted from the CNS to the respiratory muscles. Pathophysiology Mechanisms of apnea of prematurityĬentral Apnea - A pause in alveolar ventilation due to a lack of diaphragmatic activity. ![]() Postnatal exposure to sedatives, hypnotics or narcotics. Drugs - Prenatal exposure with transplacental transfer to the neonate of various drugs (narcotics, beta-blockers).Temperature Regulation - Hypothermia or hyperthermia.Gastrointestinal - NEC or gastroesophageal reflux.Metabolic - Hypocalcemia, hypoglycemia, hyponatremia or acidosis.Pulmonary - Impairment of oxygenation and ventilation from lung disease (surfactant deficiency disease, pneumonia, transient tachypnea of the newborn, meconium aspiration, etc.).Cardiovascular - Impairment of oxygenation from congestive heart failure and pulmonary edema (PDA, coarctation, etc.), or from shunting (cyanotic heart disease).Neurological - Intraventricular hemorrhage, intracranial hemorrhage, neonatal seizures, perinatal asphyxia, or other pathology which could lead to increased intracranial pressure.Infection - Sepsis, especially in the first day of life, and nosocomial infections and/or NEC in the first weeks of life.The most common cause of apnea in the NICU is apnea of prematurity, but first ALWAYS investigate and rule out the following disorders: SequelaeĪpnea in premature infants can result in a failure of the mechanisms that protect cerebral blood flow, resulting in ischemia and eventually leukomalacia.ĭuring apneic episodes, in an attempt to protect cerebral blood flowcardiac output is diverted away from the mesenteric arteries resulting in intestinal ischemia and possibly necrotizing enterocolitis (NEC). Apnea at UIHC is defined as cessation of breathing for 20 seconds with the above symptoms. Peer Review Status: Internally Peer Reviewed DefinitionĪpnea is a "pause in breathing of longer than 10 to 15 seconds, often associated with bradycardia, cyanosis, or both." (Martin et al).
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