Question 1

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 (P_aCO₂)72 mm Hg,partial pressure of oxygen (PaO₂)88 mm Hg,oxygen saturation (S_aO₂)90%,bicarbonate (HCO₃^-)32 mEq/L on nasal cannula 2 L/min.The respiratory therapist should recommend which of the following at this time?

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 to 3 cm H₂O.

Question 2

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?

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 (V_T)setting should be between 250 and 400 mL.Fractional inspired oxygen (F_IO₂)should be less than 50% with a PEEP of 3 - 5 cm H₂O.The only answer that fits these criteria is "B."

Question 3

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

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 to 80 mm Hg;pH = 7.20 to 7.40;PaO₂ = 60 to 100 mm Hg.Note that these values may vary between institutions.Some physicians prefer to use Tromethamine (THAM)or sodium bicarbonate when pH drops below 7.20.

Question 4

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

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 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)42mm 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 lbs.The most appropriate action at this time is which of the following?

Accepted Answer

The assessment and arterial blood gases (ABG)for this patient reveals 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

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?

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 (P_aCO₂)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 to 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 7

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

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/minute are essential.

Question 8

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

Accepted Answer

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

Question 9

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

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 10

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

Accepted Answer

During the early phase of acute respiratory distress syndrome (ARDS),it is important to keep extrinsic positive-end-expiratory pressure (PEEP_E)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 PEEP_E 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 11

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?

Accepted Answer

The patient is 73 inches and weighs 200 pounds.So 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 F1F1F1S1F1F1F10 2.16 = 8.64 L.Using 7 - 10 mL/kg the set tidal volume should be between 617 mL and 880 mL.The positive-end-expiratory pressure (PEEP)should be 5 cm H₂O and the fractional inspired oxygen (F_IO₂)should be 21% or close to it unless there is hypoxemia.A frequency of 12 with a tidal volume (V_T)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 12

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)shows: pH 7.25,partial pressure of carbon dioxide (P_aCO₂)55 mm Hg,partial pressure of oxygen (P_aO₂)54 mm Hg,oxygen saturation (S_aO₂)86%,bicarbonate (HCO₃^-)24 mEq/L.The most appropriate immediate action to take includes which of the following?

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 (V_T)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 (F_IO₂)initially should be 100%;this eliminates the choice with 80%.

Question 13

An 18-year-old,5'6" and 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 bpm,tidal volume (V_T)600 mL,positive-end-expiratory pressure (PEEP)5 cm H₂O,fractional inspired oxygen (F_IO₂)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?

Accepted Answer

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

Question 14

A male patient who is 5'10" and weighs 190 lbs 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?

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 to 12 mL/kg,respiratory frequency (f)15 to 20 bpm,positive-end-expiratory pressure (PEEP)0 to 5 cm H₂O with caution and higher only if there is severe hypoxemia,and fractional inspired oxygen (F_IO₂)100% to start and titrate to keep partial pressure of oxygen (P_aO₂)between 70 and 100 mm Hg.This eliminates both synchronized intermittent mandatory ventilation (SIMV)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 15

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

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,pneumomediastimum,subcutaneous emphysema,and other forms of barotrauma.

Quiz 7: Final Considerations in Ventilator Setup

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

The application of positive pressure for patients with left ventricular failure is beneficial 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?

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

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

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

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

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

Quiz 7: Final Considerations in Ventilator Setup

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

The application of positive pressure for patients with left ventricular failure is beneficial 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?

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

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

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

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

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

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