External intercostal muscle activity during acute hypoxia in the kitten.

The effects of acute hypoxia on the recruitment of external intercostal muscle activity were determined in 12 kittens, aged 14 to 36 days. The animals were anesthetized with 1.23 +/- 0.

Costal and crural diaphragm, and intercostal and genioglossal electromyogram activities during spontaneous augmented breaths (sighs) in kittens.

Spontaneously occurring augmented breaths (sighs) are common in infants. The pattern of electrical activity of the inspiratory muscles of the thorax and upper airway during augmented breaths, however, has not been fully characterized in this less than fully mature age group. We therefore examined costal and crural diaphragm and external intercostal and genioglossal EMG activities during spontaneous augmented breaths (n = 46) in 10 anesthetized (1.

Genioglossal recruitment during acute hypoxia and hypercapnia in kittens.

We examined genioglossal and diaphragmatic EMG activities in one- and two-month-old anesthetized kittens during acute exposures to hypoxic (13% or 10% O2) and hyperoxic hypercapnic (8% CO2/50% O2/balanced N2) gas mixtures. Phasic genioglossal EMG activity, frequently characterized by a combined inspiratory-expiratory discharge pattern, was observed in 3 of 8 one-month-old vs. 7 of 7 two-month-old kittens during hypercapnia (Chi-square P less than 0.

Recruitment of intercostal muscle activity during hypercapnia in kittens.

Little is known about the respiratory behavior of the intercostal muscles within a neonatal and developmental context. We, therefore, examined intercostal muscle electromyographic (EMG) activity in kittens (1 month old, n = 8; 2 months old, n = 7) during eupnea and heightened respiratory drive induced by hypercapnia. The kittens were anesthetized with halothane (1.

Cerebral infarction in persistent pulmonary hypertension of the newborn.

Persistent pulmonary hypertension of the newborn and its attendant hypoxemia may place the infant at high risk for hypoxic-ischemic injury. In 19 infants with persistent pulmonary hypertension of the newborn, 16 of whom suffered intrapartum asphyxia, we evaluated a series of electroencephalograms (EEGs) for evidence of major focal cerebral injury, ie, persistent voltage attenuation and/or focal electrical-seizure activity. Of the 15 infants (78.