Question 1

The application of positive pressure for patients with left ventricular failure is beneficial because of which of the following?
A) Increases venous return
B) Decreases preload to the heart
C) Increases afterload to the heart
D) Improves perfusion to the myocardium

Accepted Answer

The use of positive pressure in patients with left ventricular failure will reduce venous return and therefore reduce preload to the left ventricle.

Question 2

A high pressure ventilator alarm is sounding and you are unsure if ventilation is occurring.What action should you take first?
A) Hit the alarm silent button.
B) Increase the oxygen concentration to 100%.
C) Manually ventilate the patient.
D) Increase the peak pressure alarm.

Accepted Answer

When a ventilator malfunctions during use,the clinician must first ensure that the patient is being ventilated.When in doubt,the practitioner should disconnect the patient from the ventilator,start manual ventilation using a manual resuscitation bag,silence the alarms,and call for help.

Question 3

An 18-year-old,5'6",125 lb female patient was admitted to the hospital 2 days ago for spinal meningitis.She developed sepsis and suffered hypercapnic respiratory failure.The patient was intubated and placed on volume-controlled continuous mandatory ventilation (VC-CMV),respiratory frequency (f)12 breaths/min,tidal volume (Vᴛ)600 mL,positive end-expiratory pressure (PEEP)5 cm H₂O,fractional inspired oxygen (FɪO₂)0.40.Twenty-four hours later,the patient's oxygen requirements have dramatically increased and her lung compliance has dramatically dropped,while her chest X-ray showed development of bilateral fluffy infiltrates.The most appropriate actions to take include which of the following?
A) Keep Vᴛ the same, increase f to 25 breaths/min, increase PEEP to 12 cm H₂O.
B) Decrease Vᴛ to 250 mL, increase f to 15 breaths/min, increase PEEP to 15 cm H₂O.
C) Increase Vᴛ to 550 mL, decrease f to 8 breaths/min, increase PEEP to 10 cm H₂O.
D) Decrease Vᴛ to 400 mL, decrease f to 8 breaths/min, decrease PEEP to 3 cm H₂O.

Accepted Answer

During the acute phase of the disease,adequate ventilation should be provided using a tidal volume (Vᴛ)in the range of 4-6 mL/kg while plateau pressure (Pₚₗₐₜₑₐᵤ)is maintained at <30 cm H₂O with rates of 15-25 breaths/min.For this patient the Vᴛ range should be between 244 and 488 mL with a rate between 15 and 25 breaths/min.Answer "B" fits into this guideline.

Question 4

A male patient who is 5'10" and weighs 190 lb arrives at the hospital having suffered a closed head injury in a motor vehicle accident.The patient is unconscious and a computer tomogram of the head reveals an intracranial bleed.The patient receives an intracranial pressure (ICP)monitor following neurosurgery.Initial ventilator settings should include which of the following?
A) Volume-controlled continuous mandatory ventilation (VC-CMV), respiratory frequency (f) 15 breaths/min, tidal volume (Vᴛ) 750 mL, positive end-expiratory pressure (PEEP) 5 cm H₂O, fractional inspired oxygen (FɪO₂) 1.0
B) Pressure-controlled continuous mandatory ventilation (PC-CMV), f 15 breaths/min, peak inspiratory pressure (PIP) 35 cm H₂O, PEEP 10 cm H₂O, FɪO₂ 1.0
C) Volume-controlled intermittent mandatory ventilation (VC-IMV), f 6 breaths/min, Vᴛ 300 mL, pressure support (PS) 10 cm H₂O, PEEP 5 cm H₂O, FɪO₂ 0.50
D) Pressure-controlled intermittent mandatory ventilation (PC-IMV), f 12 breaths/min, PIP 20 cm H₂O, PS 10 cm H₂O, PEEP 5 cm H₂O, FɪO₂ 0.40

Accepted Answer

The initial settings for a closed head injury patient include pressure-controlled (PC)or volume-controlled (VC)continuous mandatory ventilation (CMV),tidal volumes between 8 and 12 mL/kg,respiratory frequency (f)15-20 breaths/min,positive end- expiratory pressure (PEEP)0⁻⁵ cm H₂O with caution and higher only if there is severe hypoxemia,and fractional inspired oxygen (FɪO₂)1.0 to start and titrate to keep partial pressure of oxygen (PₐO₂)between 70 and 100 mm Hg.This eliminates both intermittent mandatory ventilation (IMV)choices.The PC-CMV choice has a peak inspiratory pressure (PIP)and PEEP that are too high for this type of patient because it would increase intracranial pressure (ICP).Choice "A" fits within the guideline for ventilation of the closed head injury patient.

Question 5

A 36-year-old female patient with a history of asthma is admitted to the ICU from the emergency department.Her respirations are 30,very labored,with accessory muscle use and bilateral inspiratory and expiratory wheezing.There is bilateral hyperresonance during chest percussion.A blood gas taken in the ICU after 1 hour of continuous aerosolized albuterol (15 mg)reveals: pH 7.38,partial pressure of carbon dioxide (PₐCO₂)42 mm Hg,partial pressure of oxygen (PₐO₂)53 mm Hg,oxygen saturation (SₐO₂)88%,bicarbonate (HCO₃⁻)25 mEq/L with nasal cannula 6 L/min.The patient is 5'5" and weighs 135 lb.The most appropriate action at this time is which of the following?
A) Continue current therapy with 20 mg albuterol and reassess in 1 hour.
B) Noninvasive positive pressure ventilation (NPPV) with bilevel positive airway pressure (bilevel PAP), f = 12, inspiratory positive airway pressure (IPAP) 28 cm H₂O, expiratory positive airway pressure (EPAP) 3 cm H₂O, fractional inspired oxygen (FɪO₂) 0.30
C) Intubate, use pressure-controlled continuous mandatory ventilation (PC-CMV), f = 8, peak inspiratory pressure (PIP) 28 cm H₂O, TI 0.75 seconds, positive end-expiratory pressure (PEEP) 3 cm H₂O, FɪO₂ 1.0
D) Intubate, use volume-controlled continuous mandatory ventilation (VC-CMV), f = 12, tidal volume (Vᴛ) 600 mL, PF 40 L/min, PEEP 5 cm H₂O, FɪO₂ 0.60

Accepted Answer

The assessment and arterial blood gases (ABG)for this patient reveal impending respiratory failure.This patient should be intubated and may possibly require sedation and paralysis,depending on the ability to ventilate with synchrony.Therefore,continuation of the current therapy is not appropriate.Noninvasive positive pressure ventilation (NPPV)is not appropriate with asthma patients who are in respiratory failure and may be unable to provide airway protection.The settings for the volume-controlled continuous mandatory ventilation (VC-CMV)are not appropriate because the tidal volume is set too high,the frequency too low,and the peak flow too low.This would not allow enough time for exhalation and may cause barotrauma.The pressure-controlled continuous mandatory ventilation (PC-CMV)mode will allow for more control over the pressures.The short expiratory time will allow time for exhalation that will decrease the likelihood of hyperexpansion of the lungs.

Question 6

Essential capabilities of an adult intensive care unit (ICU)ventilator include all of the following except:
A) expiratory pause.
B) pressure control modes.
C) flow rates up to 250 L/min.
D) respiratory rates up to 60 breaths/min.

Accepted Answer

Flow rates up to 180 L/min are suggested for adult ICU ventilators.Expiratory pause is used to measure intrinsic positive end-expiratory pressure (PEEP).The pressure control modes are essential for the ventilation of patients with low lung compliance.Respiratory rates of between 1 and 6 breaths/min are essential.

Question 7

A 70-year-old,61-inch-tall female patient was admitted with an acute exacerbation of chronic obstructive pulmonary disease (COPD).After 12 hours of oxygen therapy,bronchodilator therapy,and intravenous corticosteroids,the patient began to show signs of clinical deterioration.Her chest X-ray revealed an enlarged heart and bilateral infiltrates.Her arterial blood gas shows acute on chronic respiratory failure.It is decided that this patient requires intubation and mechanical ventilation.The most appropriate ventilator settings for this patient include which of the following?
A) Volume-controlled continuous mandatory ventilation (VC-CMV) rate 15, Vᴛ 200 mL, FɪO₂ 1.0, positive end-expiratory pressure (PEEP) 5 cm H₂O
B) VC-CMV rate 12, Vᴛ 400 mL, FɪO₂ 0.4, PEEP 3 cm H₂O
C) Pressure-controlled intermittent mandatory ventilation (PC-IMV) rate 10, peak inspiratory pressure (PIP) 30 cm H₂O, FɪO₂ 0.60, PEEP 3 cm H₂O
D) PC-IMV rate 12, PIP 35 cm H₂O, FɪO₂ 0.30, PEEP 8 cm H₂O

Accepted Answer

The tidal volume setting for patients with chronic obstructive pulmonary disease (COPD)should be 5-8 mL/kg with a rate of 8-16 breaths/min.Positive end-expiratory pressure (PEEP)should be less than or equal to 5 cm H₂O.The ideal body weight (IBW)for this patient is 50 kg.Therefore,her tidal volume (Vᴛ)setting should be between 250 and 400 mL.Fractional inspired oxygen (FɪO₂)should be <0.50 with a PEEP of 3⁻⁵ cm H₂O.The only answer that fits these criteria is "B."

Question 8

While initially ventilating a patient with acute respiratory distress syndrome (ARDS),the extrinsic positive end-expiratory pressure (PEEPᴇ)should be maintained using which of the following methods? A) 50% of intrinsic positive end-expiratory pressure (PEEP_I) B) Open lung approach C) Offset intrinsic PEEP D) Minimize mean airway pressure

Accepted Answer

During the early phase of acute respiratory distress syndrome (ARDS),it is important to keep extrinsic positive end-expiratory pressure (PEEPᴇ)high enough to at least exceed the inflection point on a slow or static pressure volume.It is generally accepted by clinicians that the deflation limb of a slow pressure-volume loop best approximates the end-expiratory pressure range required to prevent alveolar collapse.Maintaining PEEPᴇ above this pressure range helps to prevent opening and closing of small airways and alveoli.This is referred to as the open lung approach to ventilatory management.

Question 9

A 72-year-old male patient (height 6'2",weight 95 kg)with a history of congestive heart failure (CHF)presents to the emergency department complaining of shortness of breath and inability to lie down to sleep.Physical assessment reveals a very anxious patient with a pulse of 140,respirations 32,and labored with diaphoresis.Breath sounds are decreased with bibasilar coarse crackles.The patient has a productive cough of pink frothy secretions.The patient is placed on a nonrebreather mask and the resulting arterial blood gases (ABG)show: pH 7.25,partial pressure of carbon dioxide (PₐCO₂)55 mm Hg,partial pressure of oxygen (PₐO₂)54 mm Hg,oxygen saturation (SₐO₂)86%,bicarbonate (HCO₃⁻)24 mEq/L.The most appropriate immediate action to take includes which of the following?
A) Face mask continuous positive airway pressure (CPAP) 10 cm H₂O
B) Intubate, volume-controlled continuous mandatory ventilation (VC-CMV), respiratory frequency (f) 20, tidal volume (Vᴛ) 810 mL, positive end-expiratory pressure (PEEP) 8 cm H₂O, fractional inspired oxygen (FɪO₂) 1.0
C) Intubate, volume-controlled intermittent mandatory ventilation (VC-IMV), f 6, Vᴛ 425 mL, PEEP 10 cm H₂O, FɪO₂ 0.80
D) Noninvasive positive pressure ventilation (NPPV) with bilevel positive airway pressure (bilevel PAP), inspiratory positive airway pressure (IPAP) 15 cm H₂O, expiratory positive airway pressure (EPAP) 5 cm H₂O, FɪO₂ 0.60

Accepted Answer

The patient is suffering from cardiogenic pulmonary edema from congestive heart failure (CHF)and has both hypercapnic and hypoxemic respiratory failure.The use of noninvasive positive pressure ventilation (NPPV)with bilevel positive airway pressure (bilevel PAP)while waiting for pharmacological treatment to take effect would be appropriate.Face mask continuous positive airway pressure (CPAP)may not provide enough support to allow the patient to reduce the partial pressure of carbon dioxide (PₐCO₂).Although intubation is a more aggressive alternative,the choices provided are not within the guidelines for ventilation of patients with CHF.These guidelines include a tidal volume (Vᴛ)between 8 and 12 mL/kg.That would be between 405 and 648 mL.This eliminates the answer with 810 mL tidal volume.The fractional inspired oxygen (FɪO₂)initially should be 1.0; this eliminates the choice with 0.80.

Question 10

A chronic obstructive pulmonary disease (COPD)patient with an ideal body weight of 65 kg is brought to the emergency department.The patient is short of breath and using accessory muscles.Aerosolized bronchodilators are administered.The arterial blood gas reveals the following: pH 7.31,partial pressure of carbon dioxide (PₐCO₂)72 mm Hg,partial pressure of oxygen (PₐO₂)88 mm Hg,oxygen saturation (SₐO₂)90%,bicarbonate (HCO₃⁻)32 mEq/L on nasal cannula 2 L/min.The respiratory therapist should recommend which of the following at this time?
A) Intubate, volume-controlled continuous mandatory ventilation (VC-CMV) rate 15 breaths/min, tidal volume (Vᴛ) 650 mL, fractional inspired oxygen (FɪO₂) 0.50, positive end-expiratory pressure (PEEP) 6 cm H₂O.
B) Noninvasive positive pressure ventilation (NPPV) with bilevel positive airway pressure (bilevel PAP) rate 8 breaths/min, inspiratory positive airway pressure (IPAP) 10 cm H₂O, expiratory positive airway pressure (EPAP) 4 cm H₂O.
C) Intubate, pressure-controlled intermittent mandatory ventilation (PC-IMV) rate 10 breaths/min, peak inspiratory pressure (PIP) 30 cm H₂O, FɪO₂ 0.60, PEEP 3 cm H₂O.
D) Administer 30% oxygen via air entrainment mask and continuous bronchodilator therapy.

Accepted Answer

Unless critical emergency,an initial attempt with noninvasive ventilation should be tried using inspiratory positive airway pressure (IPAP)10-12 cm H₂O and expiratory positive airway pressure (EPAP)3-5 cm H₂O.

Question 11

Sigh breaths could be beneficial during which of the following situations?
A) Continuous positive airway pressure (CPAP) used for the treatment of hypoxemia.
B) Mechanical ventilation with Vᴛs = 8-10 mL/kg.
C) Ventilating acute respiratory distress syndrome (ARDS) patient with plateau pressure Pₚₗₐₜₑₐᵤ >30 cm H₂O.
D) Pressure-supported ventilation with tidal volume (Vᴛ) = 4-6 mL/kg

Accepted Answer

Sigh breaths are not indicated for patients on continuous positive airway pressure (CPAP)for hypoxemia because it may be harmful.Sighs are not recommended for patients being ventilated with tidal volumes >7 mL/kg or in the presence of plateau pressures >30 cm H₂O.Sighs may be beneficial to patients who are receiving pressure-supported ventilation and who have low tidal volumes with mild hypoxemia.

Question 12

A 45-year-old,73-inch-tall,200 lb male patient is admitted to the emergency department with an exacerbation of myasthenia gravis.The respiratory therapist assesses the patient and finds the patient's maximum inspiratory pressure is 15 cm H₂O and his vital capacity is 1200 mL.It is decided that the patient requires ventilatory support.The most appropriate ventilator settings for this patient are which of the following?
A) Pressure support ventilation (PSV) 5 cm H₂O, continuous positive airway pressure (CPAP) 10 cm H₂O, FɪO₂ 0.50
B) Pressure-controlled continuous mandatory ventilation (PC-CMV), f = 16 breaths/min, peak inspiratory pressure (PIP) = 35 cm H₂O, positive end-expiratory pressure (PEEP) 3 cm H₂O, fractional inspired oxygen (FɪO₂) 0.45
C) Noninvasive positive pressure ventilation-bilevel positive airway pressure (NPPV-BiPAP), f = 14 breaths/min, inspiratory positive airway pressure (IPAP) = 28 cm H₂O, expiratory positive airway pressure (EPAP) = 5 cm H₂O, FɪO₂ 0.30
D) Volume-controlled intermittent mandatory ventilation (VC-IMV), f = 12 breaths/min, tidal volume (Vᴛ) = 725 mL, PSV 5 cm H₂O, PEEP 5 cm H₂O, FɪO₂ 0.24

Accepted Answer

The patient is 73 inches and weighs 200 lb.Thus,ideal body weight (IBW)= 106 + 6(13)= 194 lbs,or 88 kg.The patient's body surface area (BSA)is 2.16 m².The estimated minute ventilation is 4 × 2.16 = 8.64 L.Using 7-10 mL/kg the set tidal volume should be between 617 and 880 mL.The positive end-expiratory pressure (PEEP)should be 5 cm H₂O and the fractional inspired oxygen (FɪO₂)should be 21% or close to it unless there is hypoxemia.A frequency of 12 with a tidal volume (Vᴛ)of 725 gives a minute volume of 8.7 L.This will give the patient full ventilatory support.Pressure support ventilation (PSV)is not appropriate because the patient appears too weak to breathe spontaneously.Noninvasive positive pressure ventilation (NPPV)is not appropriate because of the increased risk of aspiration.

Question 13

Methods to minimize air trapping in mechanically ventilated patients include which of the following?
A) Using a longer inspiratory time (Tɪ)
B) Switching to pressure support ventilation (PSV)
C) Increasing inspiratory flow
D) Administering a mucolytic agent

Accepted Answer

To minimize air trapping,or intrinsic positive end-expiratory pressure (PEEPɪ),the following steps may be taken: switch to pressure-controlled continuous mandatory ventilation (PC-CMV)with a short inspiratory time (Tɪ),use a lower tidal volume (Vᴛ),maintain a clear airway,administer bronchodilators for bronchospasm,and increase inspiratory flow to lengthen expiratory time (Tᴇ).

Question 14

Patients with acute severe asthma requiring mechanical ventilation are difficult to manage because of which of the following?
A) Diaphragmatic paralysis
B) Increased lung compliance
C) Decreased airway resistance
D) Uneven alveolar hyperexpansion

Accepted Answer

Increased airway resistance from bronchospasm,increased secretions,and mucosal edema cause air trapping,which can cause uneven hyperexpansion of various lung units.This can cause rupture or compress other areas of the lungs leading to pneumothorax,pneumomediastinum,subcutaneous emphysema,and other forms of barotrauma.

Question 15

During mechanical ventilation,a patient with a closed head injury develops the Cushing response.This may be immediately managed by using which of the following?
A) Pressure-controlled continuous mandatory ventilation (PC-CMV) with positive end- expiratory pressure (PEEP)
B) Sedation and paralysis
C) Permissive hypercapnia
D) Iatrogenic hyperventilation

Accepted Answer

The Cushing response is the normal response to acute increases in intracranial pressure (ICP).This includes hypertension with bradycardia.Iatrogenic hyperventilation,although controversial,is recommended when there is acute uncontrolled increased ICP.The partial pressure of carbon dioxide in the arteries (PₐCO₂)should be maintained between 25 and 30 mm Hg or titrated to the ICP if it is being monitored.This is a temporary solution and should be gradually reversed within 24-48 hours,allowing acid-base balance to restore itself.The use of pressure-controlled continuous mandatory ventilation (PC-CMV)and positive end-expiratory pressure (PEEP)can increase ICP further.Sedation and paralysis should only be used in extreme cases when the ventilator and patient are asynchronous (usually with severe asthma).Permissive hypercapnia may result in further increases in ICP.

Question 16

The statement that is true concerning the use of permissive hypercapnia in the management of patients with acute respiratory distress syndrome (ABGs)includes which of the following?
A) The pH may be allowed to drop as low as 7.1.
B) Tromethamine (THAM) may be used to keep the pH above 7.2.
C) Partial pressure of carbon dioxide (PₐCO₂) needs to rise rapidly to achieve success.
D) PₐCO₂ should not be allowed to rise above 60 mm Hg.

Accepted Answer

acceptable end points for the management of acute respiratory distress syndrome (ARDS)based on arterial blood gases (ABGs)are partial pressure of carbon dioxide (PₐCO₂)= 40-80 mm Hg; pH = 7.20-7.40; PₐO₂ = 60-100 mm Hg.Note that these values may vary among institutions.Some physicians prefer to use tromethamine (THAM)or sodium bicarbonate when pH drops below 7.20.

Quiz 7: Final Considerations in Ventilator Setup

The application of positive pressure for patients with left ventricular failure is beneficial because of which of the following?

A high pressure ventilator alarm is sounding and you are unsure if ventilation is occurring.What action should you take first?

Essential capabilities of an adult intensive care unit (ICU) ventilator include all of the following except:

While initially ventilating a patient with acute respiratory distress syndrome (ARDS) ,the extrinsic positive end-expiratory pressure (PEEPᴇ) should be maintained using which of the following methods?

Sigh breaths could be beneficial during which of the following situations?

Methods to minimize air trapping in mechanically ventilated patients include which of the following?

Patients with acute severe asthma requiring mechanical ventilation are difficult to manage because of which of the following?

During mechanical ventilation,a patient with a closed head injury develops the Cushing response.This may be immediately managed by using which of the following?

The statement that is true concerning the use of permissive hypercapnia in the management of patients with acute respiratory distress syndrome (ABGs) includes which of the following?