NURS 663 Exam 2 Test Review : Updated Solution

What is SaO2 - ANS ---% saturation of arterial hemoglobin with oxygen What forces act on alveoli and keep them open? - ANS ---Negative pressure from the thorax What drives bulk flow of air? - ANS ---The pressure gradient between the alveoli and the outside air. What are the passive properties of the lungs and chest wall - ANS ---The lungs tend to collapse while the chest wall tends to expand when does intrapleural pressure become more positive - ANS ---When the volume in the lungs is increased What is minute ventilation - ANS ---The amount of air inhaled in 1 min. Tidal volume * Respiratory rate When standing upright, what part of the lung is more compliant? - ANS ---The apex Describe the difference between minute ventilation and alveolar ventilation - ANS ---Minute ventilation = TV * RR Alveolar ventilation = (TV - dead space) *RR alveolar ventilation is only the amount of air inhaled that participates in respiration. How does fibrosis affect compliance in the lungs? - ANS ---Compliance is decreased and therefore there is increased work required, increased muscle effort, and lower FRC What affect does emphysema have on compliance in the lungs? - ANS ---Compliance is increased and therefore there is decreased elastic recoil of the lungs, Elevated FRC and increased work for breathing