Practice Questions
A patient recovering postoperatively is receiving ventilation in the SIMV mode. The patient has normal ABG levels with the use of 35% O2 but is still drowsy. The respiratory therapist should recommend decreasing the: A. SIMV rate B. Inspiratory time C. VT D. Flow rate
A, To facilitate weaning this postoperative patient from the ventilator, the SIMV rate should be reduced. This will stimulate the patient to begin breathing more on his or her own.
To begin the weaning process from the ventilator, a patient should be able to obtain a MIP of at least A. -10 B. -20 C. -30 D. -40
B, Although a normal MIP level is -50 to -100 cm H2O, an MIP of at least -20 cm H2O is an indication that the patient can take deep enough breaths to produce an adequate cough and maintain secretion clearance. MIP is also referred to as negative inspiratory force (NIF).
A 5 ft 5 in 120 kg (264 lbs) woman is brought to the ED and is receiving ventilation with a manual resuscitator and mask at 100% FiO2. A drug overdose is suspected. After intubating the patient, the respiratory therapist is asked to recommend initial ventilator settings. What are the most appropriate settings for this patient's ventilator? A. SIMV 10, VT 700, FiO2 80% B. AC 16, VT 800, 0.60 C. AC 12, VT 600, 1.0 D. SIMV 12, VT 450, 1.0
D, Remember on the initial ventilator setup to select a ventilator rate between 10/min and 16/min; the initial VT setting should be 6-8 mL/kg. (Analysis) 105 + 5 (height in inches - 60) 105 + 5 (65 - 60) 105 + 25 = 130 lb To convert 130 lb to kg
The respiratory therapist is reviewing a patient's chart that shows the following arterial blood gas results on a 40% air entrainment mask: 7.41, 42, 275, 23 What is the most appropriate recommendation? A. Decrease oxygen to 30% B. Repeat the blood gas due to lab error C. Discontinue oxygen D. Decrease the flow to the mask
. B, As a general rule of thumb, the PaO2 can be no higher than approximately 5 times the oxygen level being breathed. So on 40% oxygen, the highest the PaO2 could be is approximately 200 torr. Therefore, this PaO2 is not possible and a lab error exists.
During CPR, the physician is preparing to administer lidocaine intravenously and discovers that the IV is infiltrated. The most appropriate action to take at this time is to: A. Instill the lidocaine down the ETT B. Administer the lidocaine using a handheld nebulizer C. Place a new IV line and administer the lidocaine D. Administer the lidocaine sublingually
A, Although lidocaine is normally given intravenously to counteract arrhythmias during CPR, it is permissible to instill it directly down the ET tube.
The physician has orderd O2 to be administered to an active 3-year-old with an SpO2 of 86%. Whih of the following delivery devices would you recommend for this patient? A. 1- to 2-L nasal cannula B. Air-entrainment mask C. Simple O2 mask D. O2 hood
A, An active 3-year-old generally tolerates a cannula much better than any kind of mask and is too large for an O2 hood.
A patient has been paralyzed with vecuronium (Norcuron) and is receiving mechanical ventilation. Which of the following ventilator monitoring alarms would be the most important? A. Low pressure B. High pressure C. Inspired gas temperature D. I:E time
A, Because the patient will not be able to breathe on his or her own, it is essential that the therapist is aware of when the patient is disconnected. The low-pressure alarm is activated if this occurs.
Failure to hyperoxygenation a patient on a ventilator before ET suctioning may result in: A. Hypoxemia B. Hypocapnia C. Bradycardia D. Hypertension
A, It is important during ET suctioning that the PaO2 be maintained within a normal range. This requires increasing the oxygen percentage during the procedure. Failure to hyperoxygenate may cause hypoxemia, resulting in cardiac arrhythmias. Bradycardia may occur as a result of vagal stimulation.
It is important to monitor plateau pressure in a patient receiving mechanical ventilation because it best reflects: A. Lung compliance B. PaO2 C. PaCO2 D. ICP
A, Lung compliance is determined by dividing the VT by the plateau pressure.
A patient receiving volume-controlled ventilation is ordered to have PEEP initiated. Observation of which of the following values will best determine the optimal level of PEEP? A. Cardiac output B. PaO2 C. PaCO2 D. VD/VT
A, Optimal PEEP is the level of PEEP that improves lung compliance without decreasing the cardiac output. When a PEEP study is done, the cardiac output is measured at different PEEP levels. When the cardiac output drops after an increase in PEEP, the PEEP should be decreased to the previous level. In other words, use the PEEP level that renders the best cardiac output. Or, if measuring the static lung compliance at various PEEP levels, use the level that produces the best lung compliance.
A 70-kg (154 lbs) male patient is receiving mechanical ventilation. The respiratory therapist notes the patient's SpO2 drops from 97% to 86%. The right lung is expanding more than the left, with clear breath sounds on the right but absent breath sounds on the left. The patient's ET tube is taped at the 29 cm mark at the lip. Which of the following should the respiratory therapist do at this time? A. Withdraw the tube to the 24 cm mark B. Recommend an immediate chest x-ray C. Advance the ET tub 2 cm D. Obtain immediate ABG levels
A, The ET tube should be positioned 2 to 6 cm above the level of the carina. That means the ET tube should be at the 21- to 25-cm mark at the teeth. In this question, the tube is at the 29-cm mark and the patient has decreased breath sounds in the left lung, which indicates the tube is in the right mainstem bronchus and must be withdrawn.
The most reliable method of determining whether the lungs of a patient receiving mechanical ventilation are getting stiffer and harder to ventilate is by measuring the A. Static lung compliance B. Dynamic lung compliance C. Spontaneous Vt D. PaO2
A, When lungs get stiffer and harder to ventilate, greater pressure is required to move the same volume of air. Because peak inspiratory pressure increases when RAW increases (e.g., when airway secretions are present or water is in the ventilator tubing), this pressure does not reflect how stiff the lungs actually are. We determine the plateau or static pressure by holding the volume in the patient's lungs for 1 to 2 s. This pressure closely relates to alveolar pressure. PEEP (if used) is subtracted from the plateau pressure and this number is divided into the VT. The results determine how compliant the lungs are.
The data below pertains to an adult receiving mechanical ventilation: PIP 50, Plat 40, VT 600, PEEP 10 On the basis of this information, the patient's static lung compliance is approximately which of the following? A. 16 B. 20 C. 27 D. 37
B Compliance = VT/plateau pressure - PEEP 600/30= 20 mL/cm H2O
While assessing a patient with chest trauma in the ICU, the respiratory therapist observes that the patient's chest tube, which is connected to an underwater seal drainage system, is outside the chest wall. Which of the following statements are correct about this situation? A. The tube should be clamped immediately B. A complete pneumothorax is possible C. The tube should be disconnected from suction D. Suction pressure should be increased
B, Because the chest tube is no longer in the pleural space, air in the space cannot be removed. Therefore, a pneumothorax is most likely present.
Administration of high O2 concentrations to a neonate for a prolonged period of time may result in which of the following. ? A. Pneumothorax B. Retinopathy of prematurity (ROP) C. Persistent pulmonary hypertension of the neonate (PPHN) D. Tetralogy of Fallot
B, If the high O2 concentration results in high PaO2 levels (>80 mm Hg), retinal detachment may occur, leading to blindness in the premature neonate. Remember, it is the high PaO2 that causes the damage, not the FIO2. In other words, a neonate using 100% oxygen with a PaO2 of 60 mm Hg will most likely not develop retinopathy of prematurity because the PaO2 is below 80 mm Hg. High FIO2 levels, on the other hand, will lead to atelectasis because of nitrogen washout of the lung and the suppression of surfactant production by the alveolar type 2 cells.
The ability of the patient to follow instructions would be indicated by which of the following? A. Orientation to person B. Performance of tasks when asked C. Ability to feed himself D. Awareness of time
B, If the patient is able to perform simple tasks when asked, this best determines his or her ability to follow instructions. This is important before administering an incentive spirometry or IPPB treatment, which requires the patient to be able to follow instructions well or the treatment will not be effective.
A patient with ARDS is receiving volume-controlled ventilation with a PEEP of 15 cm H2O and an FiO2 of 1.0 but remains hypoxemic. The PIP is 53. Which of the following ventilator modifications is the most appropriate recommendation at this time? A. Increase the PEEP to 20 B. Initiate pressure control ventilation C. Increase the PEEP to 25 D. Begin in-line bronchodilator therapy using an MDI
B, Pressure control ventilation is a useful mode for patients with noncompliant (stiff) lungs, such as those seen in patients with ARDS. Volume ventilation for ARDS patients leads to high peak pressures and an increased potential of barotrauma by overdistention of the alveoli. Using inspiratory pressures that deliver lower VT (4 to 6 mL/kg) and maintaining plateau pressures at 30 cm H2O or less will reduce the risk of overdistention of alveoli.
A 60-kg (132 lbs) 52-year-old man is admitted to the ICU for the treatment of refractory hypoxemia. He is currently on VC-SIMV and pressure support of 10 cmH2O with an FiO2 of 0.60. Other pertinent data is below: HR 120, RR 12, Spontaneous VT 400 mL, pH 7.49, PaCO2 30, PaO2 59, vent vt 500 mL, PEEP 5, total RR 22. Which of the following should the respiratory therapist recommend at this time? A. Increase the pressure support level to 15 B. Increase the PEEP to 8 C. Increase the FiO2 to 0.70 D. Decrease VT to 400
B, Refractory hypoxemia typically results from atelectasis, pneumonia, or pulmonary edema, whereby increasing oxygen levels do not correct the hypoxemia. Although the patient is hyperventilating, VT should not be decreased. The hyperventilation is a result of the low PaO2, therefore it should be increasing the PaO2 first is necessary. We should not exceed 60% oxygen to try to correct hypoxemia, so increasing the PEEP level is most appropriate.
A peripheral lung mass is to be biopsied. Which of the following procedures should be recommended to obtain the tissue sample? A. Electromagnetic navigational bronchoscopy (ENB) B. Fiberoptic bronchoscopy C. Bronchoalveolar lavage (BAL) D. Rigid bronchoscopy
B, Refractory hypoxemia typically results from atelectasis, pneumonia, or pulmonary edema, whereby increasing oxygen levels do not correct the hypoxemia. Although the patient is hyperventilating, VT should not be decreased. The hyperventilation is a result of the low PaO2, therefore it should be increasing the PaO2 first is necessary. We should not exceed 60% oxygen to try to correct hypoxemia, so increasing the PEEP level is most appropriate.
Which one of these drugs would be best to use to temporarily paralyze a patient to facilitate tracheal intubation? A. Atropine sulfate B. Succinylcholine (Anectine) C. Midazolam (Versed) D. Pancuronium bromide (Pavulon)
B, Succinylcholine is a fast-acting, short-term muscle relaxant used to aid in the intubation of combative patients. The patient will be paralyzed for only about 5 min.
A premature 3-week-old infant is receiving 2 L/min of O2 via a nasal cannula and has a PaO2 of 43 torr and a PaCO2 of 40 torr. The respiratory therapist should recommend which of the following? A. Increase the cannula flow to 2 L/min. B. Intubate and institute mechanical ventilation. C. Initiate CPAP of 4 cm H2O and 50% O2. D. Increase the cannula flow to 5 L/min
B, The air/O2 ratio for a 35% oxygen mixture is 5 : 1. To calculate total flow output from this device, add the ratio parts together and multiply by the liter flow: 6 × 6 = 36 L/min, 6 × 8 = 48 L/min, 6 × 10 = 60 L/min, 6 × 12 = 72 L/min. Total flow needed: 42 L/min. The minimum flow necessary is 8, giving a total flow of 48 L/min.
The physician orders a 35% aerosol mask to be set up for a patient who requires an inspiratory flow of 42 L/min. What is the minimum flow rate to which the flowmeter must be set to meet this patient's inspiratory flow demands? A. 6 L/min B. 8 L/min C. 10 L/min D. 12 L/min
B, The air/O2 ratio for a 35% oxygen mixture is 5 : 1. To calculate total flow output from this device, add the ratio parts together and multiply by the liter flow: 6 × 6 = 36 L/min, 6 × 8 = 48 L/min, 6 × 10 = 60 L/min, 6 × 12 = 72 L/min. Total flow needed: 42 L/min. The minimum flow necessary is 8, giving a total flow of 48 L/min.
You suspect a patient may have a pulmonary embolism. Which of the following would be the most appropriate recommendation for diagnosis of this condition. A. Bronchoscopy B. Performance of tasks when asked C. Ability to feed himself D. Awareness of time
B, The best diagnostic test to determine whether a pulmonary embolism is present is the V/Q lung scan.
A patient arrives in the emergency department after being pulled from a burning house. The respiratory therapist should recommend obtaining which of the following measurements to best determine the severity of the patient's smoke inhalation? A. SpO2 B. HbCO C. PaO2 D. Hb
B, To best determine the severity of smoke inhalation, an HbCO level should be determined with a co-oximeter. The SpO2 value should never be evaluated on a patient suspected of CO poisoning because a pulse oximeter is not capable of determining what is bound to hemoglobin. Pulse oximeters work on the principle of spectrophotometry where lightweight probes direct filtered light of specific wavelengths through the skin or digit. The light absorbed differs for saturated and desaturated blood, whether it's saturated with oxygen or a combination of oxygen and carbon monoxide. Therefore the reading will be erroneously high when HbCO is present.
The respiratory therapist is setting up a portable liquid O2 system for a patient with COPD. The patient is on 2 L/min nasal cannula, and the portable O2 container holds 4 lb of O2. The therapist should explain to the patient that the O2 supply will last for approximately what length of time? A. 4.5 hours B. 8 hours C. 11.5 hours D. 14 hours
C
To most effectively increase a sedated, paralyzed patient's alveolar minute ventilation while the patient is on volume-controlled ventilation in the assist-control mode, you would recommend increase which of the following? A. PEEP B. Inspiratory flow C. VT D. Ventilator rate
C Alveolar minute ventilation = (VT - VD) × respiratory rate It represents the volume actually reaching the alveoli per minute. It takes into account anatomic dead space (VD), which is approximately 1 mL/lb of body weight. Anatomic VD is that portion of the airway where no gas exchange occurs. If a patient's alveolar minute ventilation is to be increased, the VT must be increased. If only the ventilator rate is increased, the same VT is delivered, even though the minute ventilation (VT × RR) increases.
The respiratory therapist notes the following date while reviewing the patient's chart: Cdyn -42, Cstat -32 The therapist should conclude which of the following? A. Airway resistance is 10 B. A pneumothorax has likely developed C. The data is erroneous. D. The patient has sever obstructive disease
C, Dynamic compliance can never be higher than static compliance. To determine static compliance the plateau pressure (a lower number than PIP) is divided into the VT, whereas when calculating dynamic compliance the PIP ( a higher number than plateau) is divided into the VT. Therefore, the dynamic compliance is always be lower than static compliance, so this data is inaccurate.
An 80 kg (176 lbs) patient with ARDS is intubated and is reviving mechanical ventilation with the following settings: SIMV 10, 400 mL, 10 PEEP, 0.50 The respiratory therapist notes that the patient's SpO2 has dropped from 98% to 85% over the past 2 hours. The therapist notes the PIP has increased from 36 to 46, and the plat has increased from 18 to 28. Which of the following should the therapist recommend? A. Increase FiO2 to 1.0 B. Suction the patient C. Increase the PEEP to 12 D. Administer aerosolized albuterol
C, Looking at the data, you will notice the SpO2 is dropping, along with an increasing plateau pressure. The increasing plateau pressure indicates lung compliance is decreasing; the lungs are getting stiffer and harder to ventilate and oxygenate. This most likely is the result of atelectasis. This can be corrected by increasing the PEEP level, which should improve oxygenation.
An 8 day old neonate is receiving pressure-controlled ventilation. Over the past 36 hours, the neonate's PaO2 has decreased from 58 to 47. The physician wants to increase the mean airway pressure. Which of the following should the respiratory therapist recommend increasing? 1. Inspiratory pressure 2. Expiratory time 3. Inspiratory time A. 1 only B. 3 only C. 1 and 3 only D. 2 and 3 only
C, Mean airway pressure () is the average pressure applied to the airways over a specific period of time. () is affected by ventilator rate, PIP, and inspiratory time. will increase with increases in rate, PIP, or inspiratory time.
The respiratory therapist palpates o pulse on a patient but the ECG monitor shows QRS complexes on the tracing. The therapist should: A. Get a stat ABG B. Recommend defibrillation at 250 J C. Begin cardiac compressions D. Recommend cardioversion at 120 J
C, Regardless of what the ECG monitor is recording, if the patient has no pulse, compressions must be started immediately. An example of this rare situation is electromechanical dissociation (EMD), also referred to as pulseless electrical activity (PEA), in which the ECG monitor does not reflect the actual mechanical activity of the heart.
Inspiratory stridor is the major clinical sign of: A. Tracheal malacia B. Tracheal stenosis C. Glottic edema D. Laryngotracheal web
C, Stridor is a loud, high-pitched sound heard in the upper airway, generally in the glottic area where airflow is partially obstructed. Glottic edema is most commonly observed after extubation. An ET tube resting on the vocal cords may lead to inflammation and swelling of the glottic opening, resulting in stridor.
A postoperative 46 year old, 80 kg (176 lbs) patient is breathing spontaneously at a rate of 30/min with an FiO2 of 0.50. The following ABG results are obtained: pH 7.29, PaCO2 62, Pao2 64, HCO3- 29 Mechanical ventilation is institued with a CT of 600 mL and an FiO2 or 0.5. The SIMV rate should be set on: A. 4 B. 8 C. 15 D. 20
C, The initial ventilator rate on the exam should be 10/min to 16/min. Generally, do not select a rate that is below 10 or above 16 for the initial rate setting. Higher rates may be indicated on ARDS patients.
Pa patient with COPD is in the ED and is complaining of shortness of breath. ABG results with the patient breathing room are is below: 7.31, 62, 44, 34 The most important recommendation for O2 Therapy is which of the following? A. Simple mask at 10 L/min B. Nasal cannula at 6 L/min C. Air-entrainment mask at 28% D. Aerosol mask at 40%
C, The patient with COPD in this problem has chronic retention of CO2, as evidenced by the elevated HCO3 level on admission. This indicates compensation has occurred and suggests this patient has chronic hypoxemia. The PaO2 should be maintained between 50 and 65 mm Hg to prevent suppressing the ventilator drive. The oxygen device of choice for these patients is an air entrainment mask at, initially, 24% to 35%.
A 6 day old premature infant of 30 weeks gestational age is experiencing frequent periods of apnea with desaturation. Which of the following medications should the respiratory therapist recommend? A. Surfactant (Survanta) B. Albuterol (Proventil) C. Theophylline D. Naloxone (Narcan)
C, Theophylline has respiratory stimulant properties that help prevent apneic spells in neonates. Albuterol is a bronchodilator. Naloxone is often administered to newborns to reverse the narcotic depressant effects sometimes passed from the mother to the infant through the placenta before birth. Surfactant is used to treat alveolar collapse in the newborn.
ET tube cuff pressure should be maintained at which of the following levels? A. 5 to 10 B. 20 to 30 C. 35 to 45 D. 40 to 50
C, Theophylline has respiratory stimulant properties that help prevent apneic spells in neonates. Albuterol is a bronchodilator. Naloxone is often administered to newborns to reverse the narcotic depressant effects sometimes passed from the mother to the infant through the placenta before birth. Surfactant is used to treat alveolar collapse in the newborn.
The respiratory therapist is transporting a patient with a nasal cannula running at 6 L/min. For the Ecylinder to last at least 1 hr, what is the minimum amount of pressure it must contain? A. 1000psig B. 1200 psig C. 1400 psig D. 1600 psig
C, When working a problem like this, don't worry about arranging the equation to solve for pressure. Use the equation you are most familiar with. Start with choice B and determine whether this is enough pressure to run the tank for at least 1 h. Because the answer is only 56 min, use the next pressure to calculate cylinder running time. By starting with choice B, you will not have to do more than two calculations.
The following data has been collected on a 75kg (165 lbs) patient receiving volume-controlled ventilation. SIMV 4, spontaneous RR 20, Vt 600, 0.35, pH 7.29, PaCO2 50, PaO2 72, HCO3 26. On the basis of this data, which of the following should the respiratory therapist recommend? A. Increase Vt to 650 B. Increase FiO2 to 0.40 C. Increase rate to 8/min D. Change to AC and rate of 15
D, A blood gas level is considered compensated when both the PaCO2 and HCO3− are abnormal and the pH level is normal. Respiratory acidosis is caused by an elevated PaCO2, which drops the pH to below normal levels. If the patient's lungs are not ventilated better to decrease the PaCO2, the HCO3− levels in the blood begin to increase (renal compensation), which increases the pH toward normal. When the pH reaches the normal range, it is called fully compensated. The most common example of this type of blood gas level is the patient with severe COPD who has chronic retention of CO2 and remains in a constant state of compensation.
Tracheal secretions tend to dry out in an intubated patient when inspired air has which of the following characteristics? A. A water vapor pressure of 47 B. 50 mg of particulate water/L of gas C. An absolute humidity of 24 D. 44 mg of particulate water
D, A blood gas level is considered compensated when both the PaCO2 and HCO3− are abnormal and the pH level is normal. Respiratory acidosis is caused by an elevated PaCO2, which drops the pH to below normal levels. If the patient's lungs are not ventilated better to decrease the PaCO2, the HCO3− levels in the blood begin to increase (renal compensation), which increases the pH toward normal. When the pH reaches the normal range, it is called fully compensated. The most common example of this type of blood gas level is the patient with severe COPD who has chronic retention of CO2 and remains in a constant state of compensation.
Which of the following sets of ABG measurements would indicate compensated respiratory acidosis? A. pH 7.26, PCO2 60, PO2 68, HCO3 26 B. pH 7.42, PCO2 39, PO2 87, HCO3 22 C. pH 7.25, PCO2 61, PO2 75, HCO3 26 D. pH 7.37, PCO2 58, PO2 60, HCO3 31
D, A blood gas level is considered compensated when both the PaCO2 and HCO3− are abnormal and the pH level is normal. Respiratory acidosis is caused by an elevated PaCO2, which drops the pH to below normal levels. If the patient's lungs are not ventilated better to decrease the PaCO2, the HCO3− levels in the blood begin to increase (renal compensation), which increases the pH toward normal. When the pH reaches the normal range, it is called fully compensated. The most common example of this type of blood gas level is the patient with severe COPD who has chronic retention of CO2 and remains in a constant state of compensation.
A patient is receiving volume-controlled ventilation, and the low pressure alarm suddenly sounds. The corrective action is to: A. Suction the patient B. Begin manual ventilation C. Increase the flow D. Determine whether the patient is disconnected from the ventilator
D, The low-pressure alarm will sound if there is a leak in the ventilator tubing or around the ET-tube cuff, the patient is disconnected from the ventilator, or the low-pressure alarm is set too high. Suctioning the patient could be indicated if the high-pressure alarm is triggered.
A 58 year old patient with emphysema enters the ED on a 2 L/min nasal cannula. Blood for the ABG analysis is drawn, and after the results are evaluated, the O1 flow is increased to 5/. Below are the ABG results for both flow rates: 2 L/min: 7.34, 62, 44, 35 5 L/min: 7.28, 77, 52, 35 On the basis of this data, which of the following should the respiratory therapist recommend? A. Decrease the liter flow to 3 B. Initiate CPAP at 4 and 60% C. Increase the liter flow to 6 D. Institute NPPV
D, This patient with COPD clearly has chronic hypoxemia and hypercapnia, as evidenced by the initial ABG results with the use of 2 L/min. When the ABG results reveal elevated HCO3− levels on admission, compensation of the respiratory acidosis is occurring. This patient's primary problem is his PaO2, which should be maintained in the 50- to 65-mm Hg range. As the liter flow was increased, the patient's ABG results worsened, as reflected by an increasing PaCO2 and a decreasing pH. Automatically, the thought of suppressing the patient's ventilator drive comes to mind. However, for this to occur, the PaO2 must be higher than 65 mm Hg. The PaO2 is only 52 mm Hg, which is normal for this patient. The cause of the patient's deteriorating ventilatory status is not the result of the excessive oxygen but rather the result of a worsening pulmonary condition. The patient's lungs need to be ventilated more effectively, and this may be done initially with noninvasive positive pressure ventilation (NPPV), . The patient avoids being intubated yet still receives positive pressure ventilation. It buys some time for the patient so that the pulmonary problem may be treated and the patient can avoid intubation and mechanical ventilation. Because patients with COPD are typically difficult to wean from the ventilator, it is to their advantage to attempt NPPV first.
