1. Which of the following pressures van throughout the normal breathing cycle?I. alveolar pressure II. body surface pressure III. mouth pressure IV. pleural pressure A. II and IVB. I. II, III, and IVC. II, I and IVD. I and IV
D. I and IV
2. Which of the following pressures normally remains negative (relative to atmospheric pressure) during quiet breathing?A. PalvB. PplC PaoD Pbs
B. Ppl
3. Which of the following pressure gradients is responsible for the actual flow of gas into and out of the lungs during breathing?A. transthoracic pressure gradient (Ppl - Pbs)B. transrespiratory pressure gradient (Palv � Pao)C. transcanadian pressure gradient (Ppc - Pb)D. transpulmonary pressure gradient (Palv � Ppl)
B. transrespiratory pressure gradient (Palv � Pao)
4. Which of the following pressure gradients is responsible for maintaining alveolar intlation?A Transpulmonary pressure gradient (Palv � Ppl)B. Transthoracic pressure gradient (Ppl - Pbs)C. Transcanadian pressure gradient (Ppc - Pb)D. Transrespiratory pressure gradient (Palv � Pao)
A Transpulmonary pressure gradient (Palv � Ppl)
5. Which of the following statements about alveolar pressure (P during normal quiet breathing is true?A. It is positive during inspiration and negative during expiration. B. it is the same as intrapleural pressureC It is negative during inspiration and positive during expiration.D. It always remains less than atmospheric pressure.
C It is negative during inspiration and positive during expiration.
6. During normal tidal ventilation, the transpulmonary pressure gradient (Palv � Ppl) reaches its maximum value at what point in the cycle?A. end-expirationB. mid-inspirationC. mid-expirationD. end-inspiration
D. end-inspiration
7. During expiration why does gas flow out from the lungs to the atmosphere?A. P is less than at the airway opening.B. P is the same as at the airway opening.C Palv is greater than at the airway opening. D. Airway pressure is greater than P
C Palv is greater than at the airway opening
8. What forces must be overcome to move air into the respiratory system? I. tissue movementII. elastic forces of lung tissueIII. airway resistanceIV. surface tension forcesA. I, II, and IIIB. IV onlyC. I, II, III, and IVD. II and IV
C. I, II, III, and IV
9. What term is used to note the difference between inspiratory lung volume and expiratory lung volume at any given pressure?A, alveolar aphasiaB. hysteresisC. pleural pressure variance D. transpulmonary pressures
B. hysteresis
10. The presence of surfactant in the alveoli tends to do which of the following? A. increase resistanceB. decrease surface tensionC. decrease complianceD. increase elastance
B. decrease surface tension
11. How is compliance computed?A. change in volume/change in pressureB. change in pressure/change in volumeC. change in volume/change in flowD. change in pressure/change in flow
A. change in volume/change in pressure
12. Normal lung compliance is approximately which of the following?A. 2.00 L/cm HB. 10.00 L/cm HC. 0.20 L/cm HD. 0.01 L/cm H
C. 0.20 L/cm H
13. A lung that loses elastic fibers (as in emphysema) would exhibit which of thefollowing characteristics?A. decreased airways resistanceB. increased airway resistanceC. decreased pulmonary vascular resistanceD. increased pulmonary compliance
D. increased pulmonary compliance
14. A fibrotic lung would exhibit which of the following characteristics?A. decreased surface tensionB. decreased PVRC. decreased lung complianceD. decreased airway resistance
C. decreased lung compliance
15. Total lung�thorax compliance in normal subjects is about what level? A. 0.1 L/cmHB. 1.0 L/cm HC. 2.OL/cmHD. 0.2L/cmH
A. 0.1 L/cmH
16. How is airway resistance (Raw) computed?A. change in pressure/change in volumeB. change in volume/change in pressureC. change in volume x change in pressureD. change in pressure/flow
D. change in pressure/flow
17. Normal Raw is approximately which of the following?A. 0.5 to 2.5 cm HB. 20.0 to 25.0 cm HC. 15.0 to 20.0 cm HD. 0.1 to 0.2 cm H
A. 0.5 to 2.5 cm H
18. Which of the following factors affects Raw?I. pattern of gas flow (e.g., laminar versus turbulent)II. characteristics of the gas being breathedIII. diameter and length of the airwaysIV. variations in surrounding lung compliance from auto-PEEPA. I, II, and IIIB. II and IVC. IV onlyD. I, II, III, and IV
D. I, II, III, and IV
19. According to Poiseuille�s law, which of the following statements are true if we wish to maintain a constant flow of gases?A. Large jumps in driving pressure are needed to overcome airway narrowing.B. Alveolar recruitment has its greatest affect on flow.C. Halving the tube radius will require a 16-time increase in driving pressure.D. The driving pressure varies directly with the airway circumference.
C. Halving the tube radius will require a 16-time increase in driving pressure.
20. Most of the drop in pressure due to frictional resistance to gas flow occurs in what region?A. nose, mouth, and large airwaysB. respiratory bronchiolesC. terminal respiratory unitD. terminal bronchioles
A. nose, mouth, and large airways
21. traditional physical terms, how is work defined?A force x distanceB. force x timeC. mass x accelerationD. mass x force
A force x distance
22. Which of the following formulas is used to compute the mechanical work of breathing?A. change in pressure x change in flowB. change in pressure x change in volumeC. change in pressure/flowD. change in volume/change in pressure
B. change in pressure x change in volume
23. In a normal individual, what is the oxygen cost of breathing as a percentage of the body�s total oxygen consumption?A. 10%B. 20%C. 75%D. 35%
C. 75%
24. Regional factors affecting the distribution of gas in the normal lung result in which ofthe following?A. More ventilation goes to the bases and lung core.B. More ventilation goes to the bases and lung periphery.C. More ventilation goes to the apexes and lung core.D. More ventilation goes to the apexes and lung periphery.
B. More ventilation goes to the bases and lung periphery.
25. During normal inspiration, which of the following occurs?A. Alveoli at the bases expand less than those at the apexes.B. Central alveoli expand more than those at the periphery.C. Alveoli at the apexes expand more than those at the bases.D. Alveoli at the apexes expand less than those at the bases.
D. Alveoli at the apexes expand less than those at the bases.
26. Given a constant resistance, how will increasing the compliance of a lung unit alter gas movement into and out of the alveolus?A. Both filling and emptying will be slower.B. The alveolus will fill and empty more quickly.C. The alveolus will fill more quickly but empty more slowly.D. The alveolus will fill more slowly but empty more quickly.
A. Both filling and emptying will be slower.
27. Which of the following statements apply to a lung unit with higher resistance than normal?A. Volume to this area will remain the same under all conditions.B. It will fill and empty more rapidly than a normal lung unit.C. There will be less volume change for a given pressure change.D. A given volume change will require less of a pressure change.
C. There will be less volume change for a given pressure change.
28. Which of the following formulas are used to compute the time constant of a lung unit?A. change in pressure x flowB. resistance/elastanceC. resistance x complianceD. compliance/resistance
C. resistance x compliance
29. Which of the following lung units would empty and fill most slowly? A. a unit with high resistance and low complianceB. a unit with low resistance and low complianceC. a unit with low resistance and high complianceD. a unit with high resistance and high compliance
D. a unit with high resistance and high compliance
30. If a patient has a VT of 370 ml and a respiratory rate of 20 breaths per minute, what isthe minute ventilation?A. 6.45 L/minB. 2.40 L/minC. 3.70 L/minD. 7.40 L/min
D. 7.40 L/min
31. A patient has a VT of 625 ml and a physiological dead space of 275 ml and is breathing at a frequency of 16 per minute. What is the alveolar ventilation (VA)? A. 4400 mil/minB. 7000 mil/minC. 3000 mil/mmD. 5600 mil/min
D. 5600 mil/min
32. A normal 150-lb man is breathing at a rate of 17 with a tidal volume of 450 ml. By estimation, what is his approximate alveolar ventilation?A. 5.10L/minB. 7.65 L/minC. 2.60 L/minD. 3.85 L/min
A. 5.10L/min
33. Blockage of the pulmonary arterial circulation to a portion of the lung would cause which of the following?A. increase in anatomical dead spaceB. decrease in anatomical dead spaceC. increase in alveolar dead spaceD. decrease in physiologic dead space
C. increase in alveolar dead space
34. In what portion of the lungs does alveolar dead space normally occur? A. apicesB. basesC. middle portions of the lungsD. terminal respiratory units
A. apices
35. Which is the correct formula to calculate the alveolar minute ventilation of a spontaneously breathing subject?A. f x (VT - VDSphys)B. f x VDS/VTC. f x (VT + VDsphys)D. f x V
A. f x (VT - VDsphys)
36. In clinical practice measuring the physiologic dead space ventilation is achieved by using which formula?A. Bernoulli�s equationB. modified Shunt equationC. Reynold�s equationD. modified Bohr equation
D. modified Bohr equation
37. In normal individuals, approximately what fraction of the VT is wasted ventilation (does not participate in gas exchange)?A. l/4B. 1/3C. 1/2D. 2/3
B. 1/3
38. Which of the following diseases or disorders is most likely to result in an increasedVd/VT ratio?A. pulmonary embolusB. pulmonary fibrosisC. pneumoniaD. atelectasis
A. pulmonary embolus
39. What will happen if the rate of breathing increases without any change in total minute ventilation A. The dead space ventilation per minute will decrease.B. The VA per minute will increase.C. The VA per minute will decrease.D. The VA per minute will remain constant.
C. The VA per minute will decrease.
40. Which of the following ventilatory patterns would result in the MOST wasted ventilation per minute (assume constant physiologic dead space)?FrequencyTidal VolumeA. 16220B. 30170C. 25200D. 8800
B. 30170
41. How can the body effectively compensate for an increased VA. decreased respiratory rateB. increased tidal volumeC. decreased drive to breathD. increased respiratory rate
B. increased tidal volume
42. Under resting metabolic conditions, how much carbon dioxide does a normal adult produce per minute?A. 300 ml/minB. 150 ml/minC. 200 ml/minD. 250 ml/mm
C. 200 ml/min
43. Hypoventilation is defined as:A. elevated blood carbon dioxide levelB. low blood oxygen levelC. very slow respiratory rate �D. decreased tidal volume
A. elevated blood carbon dioxide level
44. A patient has a PCO of 56 mm Hg. Based on this information, what can be concluded?A. The patient is hyperventilating.B. The patient�s breathing rate is fast.C. The patient is hypoventilating.D. The patient�s VT is low.
C. The patient is hypoventilating.
45. Given a constant carbon dioxide production, how will changing the level of VA affect the PaCOA. decrease in VA will decrease PaCOB. An increase in VA will increase PaCOC. An increase in VA will decrease PaCOD. PaCO is unaffected by changes in VA.
C. An increase in VA will decrease PaCO
46. What is ventilation in excess of metabolic needs called?A. hyperpnea B hyperventilationC. hypopnea D. hypoventilation
B hyperventilation
47. What is the single best indicator of the adequacy or effectiveness of VA?A. Pa02B. PAO2 C PaCO2D.VT
C PaCO2