NBRC Mock TMC Exam Review Questions and answers, Latest update version. Rated A+ A patient is receiving O2 from an E cylinder at 4 L/min through a nasal cannula. The cylinder pressure is 1900 psig. How long will the cylinder run until it is empty? A. 47 min B. 1.7 h C. 2.2 h D. 3.6 h - ✔✔E cylinder = 0.28 1900x0.28/4 = 133/60 = 2.21 Answer: C. 2 hours, 21 minutes After the Respiratory Therapist sets up a nonrebreathing mask on a patient at a flow rate of 10 L/min, the reservoir bag collapses before the patient finishes inspiring. The RT should do which of the following? A. Change to a simple mask at a flow rate of 10 L/min B. Remove the one-way valve from the exhalation port. C. Place the patient on continuous positive airway pressure (CPAP) D. Increase the flow rate to 15 L/min - ✔✔D. Increase the flow rate to 15 L/min A patient with carbon monoxide (CO) poisoning can best be treated with which of the following therapies? A. Nasal Cannula at 6 L/min B. Simple O2 mask at 10 L/min C. CPAP and 60% O2 D. Nonrebreathing mask - ✔✔D. Nonrebreathing mask The following blood gas levels have been obtained from a patient using a 60% aerosol mask. pH: 7.47 PaCO2: 31 mmHg PaO2: 58 mmHg What should the RT recommend at this time? A. Place the patient on CPAP B. Increase the O2 to 70% C. Intubate and place the patient on mechanical ventilation D. Change to a nonrebreathing mask - ✔✔A. Place the patient on CPAP Given the following data, what is the patient's total arterial O2 content? pH: 7.41 PaCO2: 37 mmHg PaO2: 88 mmHg HCO3: 26 mEq/L SaO2: 95% Hb: 14 g/dL A. 12 mL/dL B. 14 mL/dL C. 16 mL/dL D. 18 mL/dL - ✔✔(Hb x 1.36 x SaO2) + (0.003 x PaO2) (14 x 1.36 x 0.95) + (0.003 x 88) 18.088 + 0.264 = 18.352 Answer: D. 18 mL/dL The respiratory therapist receives an order to set up a moderate level of O2 on a patient who arrives in the ED breathing at a rate of 35 breaths/min. Which of the following O2 delivery devices is most appropriate to use in this situation? A. Simple O2 mask at 10 L/min B. Nasal cannula at 4 L/min C. NRB Mask at 15 L/min D. Air-entrainment mask at 40% O2 - ✔✔D. Air-entrainment mask at 40% O2 A severe COPD patient arrives in the emergency department on a 2 L/min nasal cannula. Arterial blood gas results follow: pH: 7.32 PaCO2: 67 mmHg PaO2: 62 mmHg HCO3: 38 mEq/L Which of the following is the most appropriate recommendation? A. Increase the liter flow to 4 L/min B. Maintain the current O2 level C. Institute noninvasive positive pressure ventilation (NPPV) D. Place on a NRB mask at 12 L/min - ✔✔B. Maintain the current O2 level The physician has ordered O2 to be set up on a patient who has a spontaneous tidal volume of 500 mL and an inspiratory time of 1 second. Which of the following O2 delivery devices will deliver a flow that meets or exceeds this patient's inspiratory flow? A. 35% air-entrainment mask at 6 L/min B. 60% aerosol mask at 12 L/min C. NRB mask at 15 L/min D. Simple O2 mask at 10 L/min - ✔✔500 mL = 0.5 L 0.5/1 = 0.5 L/s (change L/s to ?/min by multiplying by 60 0.5 L x 60= 30 L/min Select the device that delivers a flow of at least 30L/min A. 35% air-entrainment mask at 6 L/min A patient breathing 50% oxygen has a PaO2 of 248 torr. Which of the following should the RT recommend? A. Discontinue O2 therapy B. Decrease the oxygen to 30% C. Titrate oxygen to maintain an SpO2 > 93% D. Repeat the blood gases because the PaO2 is not possible on this FiO2. - ✔✔C. Titrate oxygen to maintain an SpO2 > 93% Explanation: A PaO2 of 250 torr is normal on 50% O2. Remember, to determine the normal PaO2 on any given O2%, multiply the O2% by 5. This is an approximation. If titrate was not a choice, then you would discontinue the oxygen. A patient is receiving 30% oxygen via an air-entrainment mask at a flow of 5 L/min. The total flow delivered by this device is which of the following? A. 36 L/min B. 45 L/min C. 54 L/min D. 60 L/min - ✔✔(*Use 21 with O2 % less than 40%) (100- 30%)/ (30%-*21) = 70/9 = 8/1 or 8:1 ratio 8+1= 9 9x5 = 45 L/min B. 45 L/min Secretions tend to become thicker if the inspired air has which of the following characteristics? A. A relative humidity of 100% at body temperature B. 32 mg H2O per liter of gas C. A water vapor pressure of 47 mmHg D. 48 mg H2O per liter of gas - ✔✔B. 32 mg H2O per liter of gas A patient receiving 38 mg H2O per liter of gas from a nebulizer has a humidity deficit of which of the following? A. 6 mg/L B. 9 mg/L C. 12 mg/L D. 18 mg/L - ✔✔44-38= 6 A. 6 mg/L