(Test Bank) Respiratory Care Practice Exam Gary Persing, TMC Questions And Answers Plus Rationale

Rationale: Whenever the amount of H2O being delivered to the patient is less than 44 mg/L, a humidity deficit exists. This decreased H2O delivery can result in thickening of pulmonary secretions, with an increased potential of mucous plugging and atelectasis distal to the plugs. Because cooler air cannot hold as much H2O as warmer air, decreasing the heater temperature increases the humidity deficit. 3) The respiratory therapist is administering acetylcysteine (Mucomyst) via a handheld nebulizer to a patient who suddenly becomes short of breath. Which of the following is the most appropriate recommendation at this time? A. Have the patient take deeper breaths. B. Add racemic epinephrine to the nebulizer. C. Stop the treatment and administer albuterol. D. Stop the treatment and administer cromolyn sodium. Correct Answer is C Rationale: A common complication of acetylcysteine administration is bronchospasm. When respiratory difficulties occur during a Mucomyst treatment, suspect bronchospasm and administer a bronchodilating agent. 4) An intubated patient's secretions tend to become thicker and harder to mobilize in which of the following conditions? 1. Absolute humidity of 18 mg H2O/L of gas 2. 48 mg of H2O/L of gas 3. Relative humidity of 100% at 25° C 4. A H2O vapor pressure of 47 mm Hg A. 1 and 2 only B. 1 and 3 only C. 2 and 3 only D. 2 and 4 only Correct Answer is B Rationale: For delivery of 100% saturated gas at body temperature (100% body humidity) , the gas must be holding 44 mg of H2O/L of gas to have an H2O vapor pressure of 47 mm Hg. Thus, choices 1 and 3 result in a humidity deficit. Although choice 3 indicates a relative humidity of 100%, it is at only 25° C, not at body temperature (37° C), so inadequate H2O is being delivered and the body has to make up the deficit. This causes the airway to dry out and make secretions thicker. 5) Which of the following is the most appropriate ventilator VT setting for a female patient who is 5 ft, 5 in tall and weighs 85 kg (187 lb) ? A. 450 mL B. 600 mL C. 800 mL D. 900 mL Correct Answer is A Rationale: The ventilator VT should be set at 8 to 12 mL/kg of ideal body weight. Calculation of ideal body weight is as shown: Male: 106 + (6 × [ (height in inches - 60]) Female: 105 + (5 × [height in inches - 60]) In this problem, the woman is 65 inches tall. 105 + (5 × [65 - 60]) = 105 + 25 = 130 lb In other words, you add 5 lb for every inch over 5 ft to a base of 105 lb to obtain the ideal body weight. To change pounds to kilograms, divide by 2.2: 130/2.2 = 59 kg Using 6 to 8 mL/kg of ideal body weight, the most appropriate volume is 450 mL. 6) During O2 rounds, the respiratory therapist notices a nebulizer delivering very little mist to the patient's aerosol mask. Which of the following could cause this problem? 1. Inadequate flow from the flowmeter. 2. A plugged capillary tube. 3. Excessive H2O in the aerosol tubing. A. 1 only B. 1 and 2 only C. 2 and 3 only D. 1, 2, and 3 Correct Answer is D Rationale: Inadequate flow to the nebulizer results in an overall decrease in total flow and less mist output. If the capillary tube is plugged, H2O is prevented from being drawn up the tube for aerosolization to occur, with less resulting mist output. Finally, H2O build-up in the aerosol tubing results in an increased resistance to gas flow; therefore, gas flow decreases, along with total mist output. This usually occurs on heated nebulizers because of the temperature change from the outlet of the nebulizer through the cooler tubing, which results in H2O condensation in the tubing. 7) Chest film results reveal that a patient has consolidation in the left upper lobe. For selective suctioning of the left mainstem bronchus, the respiratory therapist should recommend which of the following? A. Have the patient turn the head to the right during suctioning. B. Use a Yankauer suction device. C. Use a whistle-tip suction catheter. D. Use a coude-tip suction catheter. Correct Answer is D Rationale: A coude-tip catheter is a catheter in which the tip is angled to the left for selective suctioning of the left mainstem bronchus. 8) A patient receiving volume-controlled ventilation has a PaO2 of 54 mm Hg on a PEEP of 8 cm H2O and an FIO2 of 0.50. After increasing the PEEP to 12 cm H2O, the cardiac output decreases from 5.2 to 4.0 L/min. The most appropriate action is to do which if the following? A. Discontinue PEEP and increase the FIO2 to 0.70. B. Increase PEEP to 15 cm H2O. C. Decrease PEEP to 8 cm H2O and increase the FIO2 to 0.60. D. Maintain the current settings and measure cardiac output in 1 hour. Correct Answer is C Rationale: Because increasing the PEEP level from 8 to 12 cm H2O resulted in a reduction in cardiac output, the PEEP should be returned to 8 cm H2O and the FIO2 should be increased to 0.60. The general rule of thumb for the examination is to increase the FIO2 to 0.60 before increasing PEEP. 9) This set of ABG results was obtained on a patient in the ICU on a 2-L/min nasal cannula: pH 7.22 PaCO2 27 mm Hg PaO2 78 mm Hg HCO3- 12 mEq/L BE – 13 mEq/L The correct interpretation of these ABG results is which of the following? A. Partially compensated metabolic acidosis B. Uncompensated metabolic acidosis C. Fully compensated respiratory acidosis D. Uncompensated respiratory alkalosis Correct Answer is A Rationale: The acid pH is the direct result of the decreased HCO3-level. The patient is hyperventilating to decrease the PaCO2 so that the pH returns to normal levels. Because the pH is still low, it is considered a partially compensated metabolic acidosis. 10) The following data are collected from a 2-month-old infant with respiratory distress syndrome (RDS) who is on pressure control ventilation: Mode SIMV Ventilator rate 40 breaths/min Inspiratory pressure 24 cm H2O FIO2 0.60 PEEP 4 cm H2O PaCO2 36 mm Hg PaO2 41 mm Hg pH 7.42 HCO3- 23 mEq/L BE -1 mEq/L On the basis of these data, which of the following should the respiratory therapist recommend? A. Increase PEEP to 6 cm H2O. B. Decrease rate to 35 breaths/min. C. Increase FIO2 to 0.70. D. Increase inspiratory pressure to 30 cm H2O. Correct Answer is A Rationale: The normal PaO2 for a newborn is 50 to 70 mm Hg; therefore, hypoxemia is present. The same rule applies to newborns as for adults when hypoxemia is present and the patient is on 60% O2 or higher. Do not increase the O2; instead, add or increase PEEP. Reducing the ventilator rate increases the PaCO2 and decreases the PaO2. 11) Postural drainage and percussion have been ordered for a patient with cystic fibrosis with right lower lobe atelectasis. While in the Trendelenburg position, the patient's heart rate increases from 74 to 100 beats/min and the respiratory rate increases from 18 to 28 breaths/min. The patient becomes agitated and states, “I can't breathe when my head is down.” The respiratory therapist should do which of the following? A. Continue the treatment with the patient sitting up. B. Explain the importance of this position to improve his lung condition and continue the therapy. C. Recommend replacing chest physical therapy with fluttervalve oscillation therapy. D. Recommend replacing chest physical therapy with incentive spirometry. Correct Answer is C Rationale: This form of therapy has been shown to be beneficial in the treatment of cystic fibrosis, especially for those patients who cannot tolerate the postural drainage positions indicated for treatment. 12) The following electrocardiographic (ECG) rhythm is observed on the patient's oscilloscope monitor after endotracheal (ET) suctioning: Which of the following is the most appropriate action to help prevent this from occurring? A. Decrease the suction pressure. B. Hyperoxygenate the patient. C. Use a larger suction catheter. D. Limit the time that the catheter is in the airway to 15 sec. Correct Answer is B Rationale: This ECG strip indicates sinus bradycardia, a fairly common side effect of tracheal suctioning. The sinus bradycardia is the result of vagal nerve stimulation. Hypoxemia caused by suctioning may lead to other cardiac arrhythmias. Increasing the O2 level before suctioning helps compensate for the hypoxemia so that arrhythmias are less likely to occur. 13) The following ABG values are collected from a 32-year-old patient receiving 50% O2 via aerosol mask: pH 7.44 PaCO2 35 mm Hg PaO2 60 mm Hg HCO3– 23 mEq/L BE -2 mEq/L The respiratory therapist should recommend which of the following? A. Place the patient on a nonrebreathing mask. B. Increase O2 to 70%. C. Place the patient on a CPAP mask. D. Decrease the flow to the aerosol mask. Correct Answer is C Rationale: The ABG levels reveal mild to moderate hypoxemia. Oxygen percentages over 50% to 60% should be avoided because of increasing the possibility of oxygen toxicity. 14) These data are collected from a sedated, paralyzed patient on volume-controlled ventilation in the assist-control mode: Mode Assist-control Rate 10 breaths/min VT 600 mL (0.6 L) FIO2 0.40 ABGs pH 7.29 PaCO2 50 mm Hg