NURS 271 EXAM #2 ( with complete solutions)

*OBSTRUCTIVE PULMONARY DISORDERS* correct answers What is the main function of the respiratory system? correct answers to obtain oxygen from the atmospheric air & oxygenate all of the body's cells O2 brought in from the environ transported through the respiratory tract alveoli (site of gas exchange) O2 diffuses into blood O2 perfused via blood to the rest of the body Define ventilation & respiration. correct answers ventilation = inspiration/inhalation of O2 & expiration/exhalation of CO2 (aka breathing) respiration = exchange of O2 & CO2 at the cellular level *term often used synonymously w ventilation in clinical Differentiate btwn the anatomy of the upper & lower airways of the respiratory tract. correct answers upper airway = nasopharynx, oropharynx, & laryngopharynx - warms, filters, & humidifies inspired air lower airway = larynx, trachea, bronchi, bronchioles, & alveoli - larynx = prevents aspiration during swallowing & is the site of the vocal cords Differentiate btwn the structures involved in gas exchange & those involved in conduction. correct answers respiratory zone muscles - major muscle = diaphragm *controlled by the phrenic nerve (C3-C5 of the neck), so any pt w an injury to the spine/phrenic nerve will require ventilatory support! - accessory muscles = intercostals, abdominals, trapezius, sternocleidomastoid To move air into the lungs...respiratory muscles generate negative intrapleural pressure = allows air inflowing via the pressure gradient btwn atmospheric pressure at the mouth (zero pressure) & alveolar pressure (negative pressure) conduction zone muscles = trachea, bronchi & bronchioles - influenced by SNS' B2-adrenergic receptors (relaxation) & acetylcholine receptors (constriction) gas exchange surfaces = alveoli Explain the basics of lung perfusion. correct answers bronchial arteries = bring small amts of oxygenated blood to nourish lung tissues pulmonary arteries = transport the entire CO of the R ventricle to the alveoli for gas exchange *lung = large reserve capacity for gas exchange! - at rest some pulmonary capillaries remain unperfused - during periods of high lung blood flow (ex: exercise), unperfused capillaries become perfused & already perfused capillaries become distended to compensate - hydrostatic pressure & colloid osmotic pressure influence the filtration of fluid through pulmonary capillaries ex: excessive filtration pulmonary edema impaired gas exchange