BIOL 208 Lecture Notes - Lecture 10: Infant Respiratory Distress Syndrome, Lung Volumes, Pulmonary Compliance
Document Summary
Usually not an issue (tubes are large & there are many of them) Medium size bronchiae with smooth muscle walls that could cause a problem: alveolar surface tension. Water molecules tend to pull the alveoli shut. Secretion of surfactant (soap-like substance) offsets surface tension of water. Infant respiratory distress syndrome - premature babies may have trouble producing surfactant, so when they breathe out their alveoli collapse & they have to work to rein ate them. Now, a mist is used to get surfactant into the lungs: lung compliance. Extensibility of the lung with a given change in intrapulmonary pressure. Emphysema - lots of connective tissue is present, which does not stretch easily: respiratory volumes. Tidal volume (tv) - the amount of air in a normal breath (roughly 500ml) Inspiratory reserve volume (irv) - amount of air taken in in a deep breath above tidal volume. Expiratory reserve volume (erv) - forced exhale will push out more air than normal.
