Mechanical Ventilation Exam 2.docx

In which of the following situations is volume-controlled ventilation sometimes used? - correct answer I. When a precise PaCO2 has to be maintained (some closed-head injuries). II. When more even distribution of ventilation is required Spontaneous breath modes include all of the following except: - correct answer continuous mandatory ventilation assist-control. What is the primary physiological effect of positive end-expiratory pressure (PEEP)? - correct answer Increase the functional residual capacity (FRC). Useful in treating Refractory Hypoxemia. (when a low Pa02 doesn't respond to high Fi02 Which of the following is an advantage of intermittent mandatory ventilation (IMV) over continuous mandatory ventilation (CMV)? - correct answer IMV results in lower pleural pressures for a given VE. Compared to using pressure as the trigger variable, what is the major advantage of flow-triggering? - correct answer Decreased work of breathing Which of the following modes is commonly selected for patients with neuromuscular disorders? - correct answer VC-IMV While observing a patient receiving ventilatory support, you notice that some delivered breaths are begun or ended by the machine, whereas others are begun and ended by the patient. Which of the following modes of ventilatory support is in force? - correct answer Intermittent mandatory ventilation (IMV) If the pressure waveform of a ventilator remains the same when a patient's lung mechanics change, then what is the ventilator? - correct answer Pressure controller What parameter serves as the baseline variable on all modern ventilators? - correct answer Pressure Mean airway pressure is highest with what waveform? - correct answer Rectangular pressure During pressure-targeted ventilation, which of the following settings determine VT? - correct answer I. Pressure difference II. Inspiratory time III. Time constant Flow serves as a limit variable whenever a ventilator controls what? - correct answer Flow primary parameters used to alter the breath size in pressure controlled? - correct answer Positive inspiratory pressure (PIP) & positive end-expiratory pressure (PEEP) What is the mode of ventilatory support in which patient's inspiratory efforts are augmented with a set amount of positive airway pressure? - correct answer Pressure support ventilation (PSV) A patient is receiving continuous mandatory ventilation in the control mode at a rate of 15/min. The inspiratory time is 0.8 second. What is the expiratory time? - correct answer 3.2 seconds What is the application of pressure above atmospheric at the airway throughout expiration during mechanical ventilation? - correct answer Positive end-expiratory pressure (PEEP) During volume control ventilation, the clinician has control over which of the following? - correct answer II. Volume waveform III. Flow waveform During volume-targeted ventilation, which of the following settings determine the machine-delivered minute volume? - correct answer I. Volume III. Rate A patient is receiving continuous mandatory ventilation through a constant flow generator in the control mode at a rate of 20/min with a VT of 750 mL. The inspiratory time is 1 second. What is the flow? - correct answer 45 L/min Which of the following can be used by a ventilator as a conditional variable? - correct answer I. Volume II. Pressure III. Flow IV. Time While observing a patient receiving ventilatory support, you notice that all delivered breaths are initiated or terminated by the machine. Which of the following modes of ventilatory support is in force? - correct answer Continuous mandatory ventilation A volume-cycled ventilator provides gas under positive pressure during inspiration until what point? - correct answer A preselected volume of gas is expelled from the device. During mechanical ventilation, what variable causes a breath to begin? - correct answer Trigger What is the name of a breath where a patient is able to change the inspiratory time? - correct answer Patient cycled A ventilator providing pressure support ventilation to a patient is set to flow trigger on spontaneous breaths (base flow = 10 L/min; trigger = 3 L/min below base flow). While at the bedside, you observe that the ventilator trigger rate is much higher than the patient's spontaneous rate, causing noticeable patient discomfort. Which of the following could be causing this problem? - correct answer I. Circuit leaks III. Circuit movement During volume-targeted ventilation, which of the following settings determine I:E ratio? - correct answer I. Volume II. Flow III. Rate You observe that a ventilator reaches a preset pressure early in inspiration but holds it for a specific time, after which inspiration ends. What mode of ventilatory support is in force? - correct answer Time cycled Which of the following are characteristic of a ventilator that functions as a true volume controller? - correct answer I. Its pressure waveform changes with changes in lung mechanics. II. It measures and uses volume to control the volume waveform. III. Its volume waveform stays constant with changes in lung mechanics. If lung compliance decreases while a patient is receiving mechanical ventilation with pressure-controlled continuous mandatory ventilation (PC-CMV), which of the following would occur? - correct answer tidal volume decreases Full ventilatory support is provided by which of the following modes? - correct answer Pressure-controlled intermittent mandatory ventilation (PC-IMV) rate 12 with pressure support (PS) Of the following breath descriptions, which one is considered spontaneous? a. Pressure triggered, pressure limited, time cycled b. Patient triggered, patient cycled, baseline pressure +5 cm H2O c. Time triggered, volume limited, volume cycled d. Flow triggered, pressure limited, flow cycled - correct answer b. Patient triggered, patient cycled, baseline pressure +5 cm H2O Setting flow rates high will cause which of the following to occur? - correct answer Increase peak pressures A patient has a body temperature of 40° C. How should the initial minute ventilation setting be adjusted? - correct answer Increase it by 30% The flow waveform pattern that is created during pressure targeted ventilation is which of the following? - correct answer Descending ramp During volume-targeted ventilation, which of the following settings determine I:E ratio?