Chapter 9: Noninvasive Monitoring in Neonatal and Pediatric Care Test Bank

Multiple Choice

1. What clinical parameter is critically important to monitor when mechanical ventilation is administered?

a. Blood pressure b. Heart rate c. Temperature d. Respiratory rate

ANS: A

In mechanically ventilated children, increasing intrathoracic pressure (by increasing positive end expiratory pressure, for example) can reduce venous return, resulting in decreased BP.

REF: p. 136 a. The percentage of red light that lands on the photodiode represents the SpO2 (oxygen saturation as determined by pulse oximetry). b. The percentage of infrared light that reaches the photodetector reflects the SpO2 c. The ratio of the red and infrared light that reaches the photodiode signifies the SpO2 d. The sum of the amount of red and infrared absorbed by the tissue determines the SpO2.

2. How is the percentage of functional hemoglobin that is saturated with oxygen determined via pulse oximetry?

ANS: C

A pulse oximeter sensor has two light-emitting diodes (LEDs) that function as light sources and a photodiode that measures the amount of light from the LEDs (see Figure 9-1 in the textbook). One LED emits red light, and the other diode emits infrared light. The sensor is placed over a translucent part of the body (finger, toe, earlobe, etc.). As the light from the diodes passes through the blood and tissue, some of the light from both the red and the infrared diodes is absorbed by oxyhemoglobin. The photodiode then measures the amount of light that passes through the body without being absorbed. Because oxyhemoglobin (hemoglobin bound with oxygen) and deoxyhemoglobin (hemoglobin not bound with oxygen) absorb significantly different amounts of light, the proportion of oxyhemoglobin (expressed as a percentage) is determined (see Figure 9-2 in the textbook).

REF: p. 137 a. The SpO2 will read erroneously low. b. The SpO2 will read erroneously high. c. The monitor will display a message indicating inadequate pulse. d. The monitor will display fluctuating SpO2 values between being erroneously low and high.

3. The therapist has applied a bandage-type pulse oximetry probe too tightly to an infant’s finger. What problem can be expected to occur in this situation?

ANS: C

Correct application of the sensor is crucial to the quality of readings from the pulse oximeter. The sensors should be placed firmly to avoid falling off or motion artifact, but care should be taken to avoid overtightening and compromising local circulation.

REF: p. 137

4. The therapist has been asked to measure preductal oxygen saturation. Where could the therapist place the pulse oximeter probe? a. Right thumb b. Left thumb c. Forehead d. Left earlobe

ANS: C

Sensor placement on right arm or head will reflect preductal values while the left arm and the lower parts of the body will reflect postductal oxygen saturation values.

REF: p. 138 a. The therapist should continue monitoring the patient because the reading is accurate. b. The therapist should obtain an arterial blood sample to confirm P2 level. c. The therapist should switch to using a capnometer. d. The therapist should reduce the fraction of inspired oxygen.

5. As the therapist applies a pulse oximeter finger probe to a neonate who is receiving supplemental oxygen, she notices that the SpO2 reading is 100%. What should the therapist do in this situation?

ANS: B

The sensitivity of pulse oximetry to detect the presence and degree of hyperoxia may be limited in the neonatal patient. If the oximeter is reading an SpO2 of 100%, the arterial oxygen tension (PaO2) could be between 90 and 250 mm Hg. However, many neonatal intensive care units will target an SpO2 below a certain threshold in order to reduce the risk of retinopathy of prematurity in premature babies.

REF: p. 139

6. A therapist is monitoring a child on the mechanical ventilator who is hemodynamically stable. The PetCO2 is 48 mm Hg. If accurate, what should be the PaCO2? a. 43-48 mm Hg b. 45-48 mm Hg c. 50-53 mm Hg d. Exactly the same as PetCO2

ANS: C

PetCO2 can be used as a surrogate for the arterial partial pressure of CO2 (PaCO2) within physiologic limits. Normally, PetCO2 is 2-5 mmHg below PaCO2. The reason for this is the proportion dead-space ventilation.

REF: p. 140

7. What is volumetric capnography able to determine?

I. Airway dead space

II. Alveolar tidal volume

III. Shunt fractionIV. Alveolar minute volume a. II, III, and IV only b. I only c. I, II, and IV only d. I, II, III, and IV

ANS: C

The concentration of CO2 is plotted against exhaled tidal volume to determine relevant ventilation data such as airway dead space, alveolar tidal volume, and extrapolation of CO2 elimination and alveolar minute ventilation.

REF: p. 142 a. Because of the lag time between the cardiac output and the time the blood reaches the transcutaneous electrode site b. Because the skin is much more permeable to oxygen than carbon dioxide c. Because oxygen is consumed and carbon dioxide is produced in transit from the left ventricle to the electrode site d. Because metabolism in the tissue consumes oxygen and produces carbon dioxide at the site of the electrode

8. Why do transcutaneous oxygen tension (PO2) and carbon dioxide tension (PCO2) values differ from PaO2 and PaCO2 measurements?

ANS: D

Transcutaneous measurements of PO2 and PCO2 require a heating element, built into the sensor, which elevates the temperature in the underlying tissue. Increasing the skin's temperature increases capillary blood flow to the tissues, making it more permeable to gas diffusion. The tissue under which the sensor is placed will continue to consume oxygen and produce carbon dioxide (according to their metabolic demands). Consequently, measured values obtained with a transcutaneous monitor will differ from arterial values. Generally, the PO2 is slightly lower than in the arteries, and the PCO2 is slightly higher.

REF: p. 142 a. The therapist should only continue monitoring the patient since the transcutaneous electrode is properly placed. b. The therapist should reposition the electrode on the neonate’s abdomen. c. The therapist needs to move the transcutaneous electrode to the infant’s right shoulder. d. The therapist should relocate the electrode on the sternum as close as possible to the heart.

9. While attending to a neonatal patient in the neonatal intensive care unit (NICU), the therapist notices that a transcutaneous electrode is affixed to the upper chest of the neonate. What should the therapist do at this time?

ANS: A

The site should be a highly vascular area such as the earlobe, upper chest, abdomen, thighs, or the lower back if the patient is supine; bony areas and those with limited perfusion, such as over the spine, should be avoided.

REF: p. 142 a. The temperature range set is appropriate; therefore, no action is necessary. b. The therapist should increase the temperature range to 47° C to 48° C. c. The temperature of the transcutaneous electrode needs to be reduced to 36° C to 38° C. d. The electrode needs to be repositioned and maintained at the same temperature.

10. The therapist is assessing a mechanically ventilated infant and observes that the transcutaneous electrode temperature is set between 41° C and 44° C. What action does the therapist need to take at this time?

ANS: A

Selecting a sensor temperature is important to proper operation. The temperature range is usually 41° to 44° C. Heating of the sensor requires that the site be changed on a routine basis to prevent thermal injuries. The frequency of site changes ranges from 4 to 12 hours (depending upon the device and sensor temperature) but can be reduced if necessary.

REF: p. 142

11. Which of the following is the main physiologic factor responsible for deriving accurate transcutaneous data? a. Heart rate b. Minute ventilation c. Peripheral perfusion d. Ventilation-perfusion ratios

ANS: C

Changes in perfusion can adversely affect the accuracy of transcutaneous measurements. The skin reacts to cold, shock, and certain drugs by contracting the superficial blood vessels, opening larger, deeper arterioles to achieve a shunting effect. Capillary blood flow is reduced on exposure to cold temperatures in order to reduce the loss of body heat. Shock and certain medications can also divert blood from capillaries to the central circulation. In all cases of reduced capillary perfusion, the capillary blood that is measured using a transcutaneous monitor may reflect measurements associated with venous blood, with a considerably lower PO2 and higher PCO2 (compared to values obtained with good capillary perfusion). If a patient has poor skin integrity, transcutaneous monitoring may also be contraindicated.

REF: p. 143

12. Which of the following features or characteristics apply to mainstream capnography?

I. The mainstream capnograph contains narrow tubing that can become occluded with mucus.

II. Mainstream capnography generally employs infrared spectrometers.

III. The mainstream capnograph does not add much weight to the breathing circuit. IV. The mainstream capnograph is placed at the proximal end of the endotracheal tube. a.

I and II only b. II and IV only c. I, II, and III only d. I, III, and IV only

ANS: B

Gases from an exhaled breath can reach the sample chamber in one of two ways. Mainstream capnographs are used in ventilated patients, with placement at the proximal end of an endotracheal tube (see Figure 9-5 in the textbook). This method employs infrared spectrometers. Sidestream capnograph analyzers continuously aspirate a sample of gas through a small tube to the analyzer.

REF: p. 139

13. Where on the following normal capnogram is the end-tidal carbon dioxide (PetCO2) represented?

14.

The normal capnogram can be divided into four phases (see Figure 9-6 in the textbook):

Phase A-B: The inspiratory phase, during which the sensor detects no carbon dioxide Phase B-C: The initial expiratory phase, during which carbon dioxide rapidly increases as the alveoli begin to empty

Phase C-D: The completion of expiration as the alveoli empty (alveolar plateau) and show a slight increase in carbon dioxide

Phase D-E: The beginning of inspiration as the waveform returns to zero

REF: p. 141

While working in the NICU with a mechanically ventilated newborn who is being monitored for PetCO2, the therapist observes the following capnogram: a. This capnogram is normal. b. The patient is receiving about 10 cm H2O positive end-expiratory pressure. c. The patient is rebreathing his own exhaled gas. d. The neonate is being hyperventilated.

What interpretation should the therapist make of this capnogram?

ANS: C

Rebreathing is characterized by an elevation in the A-B phase of the capnogram, with a corresponding increase in ETCO2. It indicates the rebreathing of previously exhaled carbon dioxide. Rebreathing can be caused by allowing an insufficient expiratory time or by inadequate inspiratory flow (see Figure 9-7 in the textbook).

REF: p. 141 a. Airway obstruction b. Hypoventilation c. Hyperventilation d. Increased dead space ventilation

15. The following capnogram was obtained from a newborn infant receiving mechanical ventilation.

How should the therapist evaluate this capnogram?

ANS: A

Obstruction of the expiratory flow of gas will be noted as a change in the slope of the B-C phase of the capnogram. The B-C phase may diminish without a plateau. Obstruction can be caused by a foreign body in the upper airway, increased secretions in the airways, the patient having bronchospasms, or partial obstruction of the ventilator circuit (see Figure 9-8 in the textbook).

REF: p. 141 a. The patient has received a paralytic agent. b. A paralytic agent is indicated for this patient because of the spontaneous breathing efforts represented by the downward deflections. c. The patient may have developed a pneumothorax. d. A leak has developed in the patient-ventilator system.

16. An infant demonstrates the following capnogram while being mechanically ventilated.

How should the therapist interpret this capnogram?

ANS: C

A stair-stepping of the D-E phase of the capnogram, caused by unequal and incomplete emptying of the lungs, along with a failure to return to baseline, may suggest a pneumothorax (see Figure 9-10 in the textbook).

REF: p. 142 a. To measure heat produced and lost from the body b. To calculate energy expenditure by measuring VO2 and VCO2 c. To calculate resting energy expenditure d. To measure gas exchange

17. What is the purpose of indirect calorimetry?

ANS: B

Direct calorimetry extrapolates energy expenditure by measuring heat produced and lost from the body while indirect calorimetry combines measurements of VO2 and VCO2 into an equation to calculate energy expenditure. Most energy expenditure reports will contain results for VO2, VCO2, REE, and respiratory quotient (which is VCO2/VO2 and can be used to determine substrate utilization).

REF: p. 144

18. Which of the following conditions will preclude the use of indirect calorimetry?

I. Cuffed endotracheal tubes

II. Circuit leaks

III. FiO2 40%

IV. HFOV a. I, II, and III only b. II and III only c. II and IV only d. I, III, and IV only

ANS: C

Conditions that preclude the use of indirect calorimetry include: uncuffed endotracheal tubes, cuff or ventilator circuit leaks >10-15%, FiO2 >50%, need for high-frequency ventilation or extracorporeal membrane oxygenation, and active chest tube leakage.

REF: p. 145

Chapter 10: Oxygen Administration Test Bank

Multiple Choice

1. In which of the following conditions is the oxygen-carrying capacity reduced despite the presence of a normal arterial oxygen tension?

a. Carbon monoxide poisoning b. Polycythemia c. Heart failure d. Cyanide poisoning

ANS: B

In conditions such as anemia or carbon monoxide poisoning, the oxygen-carrying capacity of the blood is reduced despite the presence of normal arterial oxygen tension (PaO2).

REF: p. 149 a. PaO2 of 80 mm Hg b. PaO2 of 60 mm Hg c. SpO2 of 92% d. SpO2 of 95%

2. What is the minimum level of oxygen tension in a child that requires oxygen administration?

ANS: B

In the child, a PaO2 less than 80 mm Hg and a SpO2 less than 95% usually indicate hypoxemia. However, general practice is to only treat SpO2 < 90% or a PaO2 < 60 mm Hg.

REF: p. 149 a. The two curves have the same position and coincide with each other. b. The adult oxyhemoglobin dissociation curve lies to the left of the fetal curve. c. The fetal oxyhemoglobin dissociation curve lies to the left of the adult curve. d. The fetal oxyhemoglobin dissociation curve lies to the right of the adult curve.

3. Where does the fetal oxyhemoglobin dissociation curve reside in comparison with the normal adult oxyhemoglobin dissociation curve?

ANS: C

Because fetal hemoglobin has a much greater affinity for oxygen, the oxygen dissociation curve is shifted to the left, allowing a higher saturation for any given PaO2

REF: p. 149 a. Continue monitoring the oxygen level of the neonate. b. An FiO2 of 1.0 needs to be administered. c. An FiO2 sufficient to raise the SpO2 to 90% needs to be given. d. An FiO2 sufficient to elevate the PaO2 to 80 mm Hg should be provided.

4. The therapist has evaluated a neonate’s oxygenation status to be as follows: PaO2, 40 mm Hg, and SpO2 (oxygen saturation as determined by pulse oximetry), 80%. What should the therapist do at this time?

ANS: C

The normal immediate postnatal PaO2 of 50-60 mm Hg corresponds closely with a SpO2 of 85-90%. For this reason, it is generally agreed that a PaO2 less than 50 mm Hg and a SpO2 less than 88% in the newborn indicate hypoxemia and necessitate initiation of oxygen therapy. The PaO2 and the SpO2 are the principal clinical indicators used to begin, monitor, adjust, and terminate oxygen administration.

REF: p. 149

5. Which of the following disorders can develop in neonates as a result of receiving concentrations of oxygen that produce a high PaO2? a. Atelectasis b. Hyperoxia c. Retinopathy of prematurity d. Bronchopulmonary dysplasia

ANS: C

The role of oxygen in the development of retinopathy of prematurity (ROP) is controversial. It is believed to cause constriction of retinal and cerebral vessels in neonates and infants, which can lead to ischemia, varying degrees of retinal scarring, and retinal detachment. Formerly referred to as retrolental fibroplasia, ROP may resolve spontaneously or result in permanent visual impairment, including blindness. Current practice supports oxygen therapy targeting SpO2 levels at 88% to 95% and maintaining a PaO2 value of 50 to 80 mm Hg in infants weighing less than 1500 g.

REF: p. 149 a. Pulmonary vasodilation b. Increased intrapulmonary shunting c. Decreased alveolar pressure d. Increased partial pressure of nitrogen in the blood

6. Which of the following problems occurs as a result of absorption atelectasis?

ANS: B

High concentrations of oxygen have been linked to atelectasis, pulmonary vasodilation, and pulmonary fibrosis. In the face of high oxygen levels, the alveolar oxygen tension (PAO2) may increase and the alveolar nitrogen decrease, resulting in absorption atelectasis. As the nitrogen is replaced by oxygen, the blood rapidly absorbs the oxygen, gas volume decreases, and atelectasis develops. High FiO2 levels may also result in pulmonary vasodilation. As the pulmonary vasculature dilates and alveolar volumes decrease, areas of ventilation–perfusion mismatch occur with increased intrapulmonary shunting and worsening of arterial oxygen delivery.

REF: p. 150

7. Which of the following oxygen-delivery devices would be most suitable for an infant being treated for choanal atresia? a. Nasal cannula b. Nasal catheter c. Oxygen hood d. Oxygen mask

ANS: C

When compared with an oxygen hood, the nasal cannula allows the patient greater mobility, which may increase interactions with the patient’s caregivers and environment. Nasal cannulas and nasal catheters are contraindicated in patients with nasal obstruction, such as facial trauma and choanal atresia. With facial trauma or choanal atresia, an oxygen hood would be the most appropriate oxygen delivery device to use because as long as the infant remains within the confine of the oxygen hood, he or she will breathe an elevated FiO2.

REF: p. 150 a. Less than 0.1 L/minute b. 0.1 to 0.2 L/minute c. 0.2 to 0.3 L/minute d. 0.3 to 0.4 L/minute

8. When weaning an infant receiving oxygen from a nasal cannula attached to a low-flow flow meter set at 100%, what range represents the recommended oxygen flow reduction from the flow meter?

ANS: B

When weaning a patient from oxygen delivered by a nasal cannula, decrease the flow in small increments of 0.1 to 0.2 L/minute.

REF: p. 152 a. Too low of an FiO2 may be delivered. b. Too high of an FiO2 may be given. c. Gastric distention may develop. d. The patient may stop breathing.

9. What is the concern when administering oxygen to a sedated infant who is wearing a nasal cannula?

ANS: B

Sedated infants may have a decreased minute ventilation, resulting in an increased FiO2 received from a nasal cannula.

REF: p. 152 a. 0.5 L/minute b. 1 L/minute c. 2 L/minute d. 3 L/minute

10. In order to decrease the risk of nasal irritation in newborns, what is the maximum flow rate recommended?

ANS: B

Excessive flows may result in drying of the nasal mucosa as well as mucosal irritation. It is recommended that maximum flow be limited to 2 L/minute in infants and newborns.

REF: pp. 152-153

11. Which of the following ranges of oxygen flow need to be set when administering oxygen to an infant via a simple mask? a. Less than 1 L/minute b. 1 to 6 L/minute c. 6 to 10 L/minute d. Greater than 10 L/minute

ANS: C

When a simple mask is used to provide supplemental oxygen to an infant, flows from 6 to 10 L/minute provide a variable FiO2 of 0.35 to 0.5. However, no data in newborns and infants are available to predict the effective FiO2.

REF: p. 153 a. Increase the oxygen flow to the device. b. Decrease the oxygen flow to the apparatus. c. Switch to a nonrebreathing mask. d. Continue monitoring the patient as the device is operating correctly.

12. The therapist notices that the reservoir bag on a partial rebreathing mask being worn by a pediatric patient collapses completely during each inspiration. What should the therapist do at this time?

ANS: A

Adjust the oxygen flow rate to a level sufficient to keep the bag partially inflated during inspiration; usually 6 to 15 L/minute is sufficient. If the reservoir bag becomes totally deflated when the patient inspires, increase the flow rate.

REF: p. 154

13. A child with an exacerbation of asthma is a candidate for the administration of heliox. Which of the following gas delivery devices is most suitable for its administration? a. Nasal catheter b. Simple mask c. Partial rebreathing mask d. Nonrebreathing mask

ANS: D

Because it is designed to provide almost 100% source gas, a nonrebreathing mask is the device recommended to deliver specific gas mixtures, as in helium-oxygen therapy, or specific concentrations from a blender.

REF: p. 154 b. Switch to a partial rebreathing mask. c. Switch to an air-entrainment mask. d. Apply positive pressure ventilation.

14. The respiratory therapist is treating a hypoxemic child with a nasal cannula at 3 L/min. However, after few hours the child becomes tachypneic, demonstrates shallow breathing, and becomes hypoxemic. What should the therapist do at this time? a. Increase flow rate on the cannula to 4 L/min.

ANS: C

In the hypoxic child with increased respiratory rates and tidal volumes, the air-entrainment mask is the preferred oxygen delivery system because it is capable of maintaining total flows in excess of the patient's inspiratory flow rate.

REF: pp. 154-155

15. Which of the following devices would be most appropriate to use for a 3-year-old patient who experiences immediate postextubation hypoxemia? a. Blow-by setup b. Partial rebreathing mask c. Aerosol mask d. T-piece

ANS: C

Both the aerosol mask and the face tent apparatus are indicated primarily for short-term administration of oxygen with high humidity, as in postextubation or postanesthesia hypoxemia.

REF: p. 155 a. It will increase the FiO2 b. It will decrease the FiO2. c. It will only affect the FiO2 if in excess of 2 mL. d. It will produce an unpredictable effect on the FiO2.

16. How will excess condensate present in aerosol tubing affect the delivered FiO2?

ANS: A

Condensate can completely obstruct gas flow or cause increased resistance to flow, which can cause the FiO2 to increase above the desired setting.

REF: pp. 155-156

17. For which of the following condition(s) is a high-flow nasal cannula contraindicated?

I. Pneumothorax

II. Apnea of prematurity

III. Severe upper airway obstructionIV. Lack of spontaneous breathing a. I, III, and IV only b. I and III only c. II and IV only d. III and IV only

ANS: A

Contraindications for use of the high-flow nasal cannula may include suspected or confirmed pneumothorax, severe upper airway obstruction, and absence of spontaneous ventilation.

REF: p. 156

Chapter 11: Aerosols and Administration of Medication Test Bank

Multiple Choice

1. When administering aerosol therapy to a pediatric patient, which of the following conditions can affect aerosol deposition?

I. Airway diameter

II. Respiratory rate

III. Body weightIV. Nasal breathing a. I and II only b. II, III, and IV only c. III and IV only d. I, II, and IV only

ANS: D

Compared with adults, infants and children have smaller airway diameters, higher and irregular breathing rates, engage in nose breathing (which filters out large particles), and often have difficulty with mouthpiece administration. Cooperation and ability to perform aerosol inhalation techniques effectively vary with the child's age and developmental ability.

REF: p. 164 b. The liver of the infant metabolizes 95% of the drug. Therefore, the lung deposition is similar to that of the adult. c. Albuterol targets only a minimal number of beta-2 receptors in the infant’s airways. d. The infant gets a higher lung dose, but it does not produce side effects.

2. The respiratory therapist verifies an order to administer albuterol 1.25 mg to a 2-kg infant. Why does this dose have the same safety and efficacy profile as a 2.5-mg dose in the adult? a. The deposition efficiency in the infant results in a similar lung dose per kg of the adult patient.

ANS: A

This reduced efficiency may result in infants receiving weight-appropriate dosing compared with adults. For example, the deposition efficiency of 0.5% of a standard dose of albuterol sulfate (2500 g) would result in a lung dose of 12.5 g, or 6.25 g/kg for a 2-kg infant, whereas a 70-kg adult with 10% deposition has a lung dose of 250 g, equivalent to 3.6 g/kg. In this example, the infant actually receives a similar but slightly greater dose per unit weight. To some extent, the reduced deposition of aerosolized bronchodilators results in safety and efficacy profiles for infants and children similar to those reported for adults.

REF: p. 164 a. Comfortably hold the mask close to the face to minimize the leak. b. Change the aerosol to a pMDI. c. Change the aerosol mask to a mouthpiece. d. Ask the mother of the child to hold the mask and continue “blow-by” therapy.

3. The respiratory therapist is administering a nebulizer with a mask to a 2-year-old child. The mask is being held away from the child’s face (“blow-by”) due to excessive crying. What should the RT consider doing to improve aerosol lung deposition?

ANS: A

Children aged between 18 months and 3 years with recurrent wheeze have reported that lung deposition with a face mask leak was 0.2% and 0.3% with pMDI and nebulizer, respectively. Screaming children without face mask leak had 0.6% lung deposition with pMDI and 1.4% with nebulizer. Lung deposition in children who were quietly breathing and without face mask leak ranged from 4.8% to 8.2%.

REF: p. 165 a. 5% b. 10% c. 15% d. 20%

4. By what percentage can breath holding increase particle deposition in the lungs?

ANS: B

A breath hold can increase deposition of the aerosol by up to 10% and is associated with a shift of deposition from the central to peripheral airways.

REF: p. 166

5. Pneumatic nebulizers operate according to which of the following physical tenets? a. Venturi principle b. Bernoulli principle c. Law of continuity d. Law of conservation of energy

ANS: B

Pneumatic nebulizers use the Bernoulli principle to drive a high-pressure gas through a restricted orifice and draw the medication and diluents into the gas stream through a capillary tube immersed in the solution. Shearing the fluid stream in the jet forms the aerosol stream that impacts against a baffle, removing larger particles that may return to the reservoir.

REF: p. 168 a. 33% b. 50% c. 66% d. 100%

6. A conventional jet nebulizer with a dead volume of 1 mL is filled with a 3-mL solution of albuterol. What percent of the medication is available for nebulization?

ANS: C

With a residual volume of 1 mL, a fill of 2 mL would leave only 50% of the nebulizer charge available for nebulization, whereas a fill of 4 mL would make 3 mL, or 75%, of the medication available for nebulization.

REF: p. 168 b. The treatment time shortens. c. The particle size remains stable. d. The nebulizer will nebulize the full dose more slowly.

7. When a conventional jet nebulizer is operated at a flow of 10 L/min versus 5 L/min, what should the respiratory therapist expect? a. The particle size gets larger.

ANS: C

For any given nebulizer, the higher the flow to the nebulizer, the smaller the particle size generated and the shorter the time required to nebulize the full dose.

REF: p. 168 b. Terminate the treatment at this time. c. Allow the nebulizer to continue the treatment for 2 more minutes. d. Add more diluent to the nebulizer cup.

8. An aerosol treatment is being administered via a jet nebulizer. After 8 minutes the nebulizer starts “sputtering.” What should the therapist do at this point? a. Tap the nebulizer cup until no more mist is produced.

ANS: B

With three different fill volumes, albuterol delivery from a nebulizer was found to cease after the onset of inconsistent nebulization (sputtering). Aerosol output declined by one half within 20 seconds of the onset of sputtering. The concentration of albuterol in the nebulizer cup increased significantly once the aerosol output declined, and further weight loss in the nebulizer was caused primarily by evaporation. The conclusion was that aerosolization past the point of initial jet nebulizer sputter is ineffective.

REF: p. 168 a. Increasing the flow rate powering the nebulizer b. Terminating the treatment prior to “sputter” c. Adding a 6 inches of tubing on the expiratory side of the nebulizer d. Using breath-enhanced nebulizers

9. Which of the following suggestions will have the most significant impact on the inhaled dose of medications with nebulizers?

ANS: D

Theoretically breath-enhanced nebulizers allow release of more aerosol during inhalation when ambient air vents through the nebulizer during inhalation and more aerosol is available. When exhaled gas is routed out the expiratory one-way valve in the mouthpiece, aerosol is not cleared from the nebulizer. Thus, breath-enhanced nebulizers may increase inhaled dose by as much as 50% compared to continuous simple jet nebulizers.

REF: p. 168 a. Rinse with vinegar and air dry. b. Rinse with sterile water and dry with a clean paper towel. c. Rinse with a mixture of vinegar and sterile water and air dry. d. Rinse with sterile water and air dry.

10. In order to guarantee the same performance of the nebulizer after repeated use, what should be suggested to the user?

ANS: D

Repeated use of a nebulizer will not alter the MMAD, or output, as long as it is properly cleaned (rinsed and dried between treatments). Failure to clean the nebulizer properly results in degradation of performance from clogging the jet (Venturi) nebulizer, increasing bacterial contamination, and the buildup of electrostatic charge in the device. The Centers for Disease Control and Prevention (CDC) recommend cleaning and disinfecting nebulizers or rinsing with sterile water between uses and then air drying.

REF: p. 170 a. Pass-over humidifiers produce smaller particles and have a greater output. b. The fraction of inspired oxygen (FiO2) used with pass-over humidifiers is easier to control. c. Pass-over humidifiers transmit fewer pathogens than pneumatic nebulizers. d. Pass-over humidifiers have a smaller residual volume than pneumatic nebulizers.

11. Why are pass-over humidifiers preferred over pneumatic nebulizer humidifiers?

ANS: C

Because nebulizers provide a route for transmission of pathogens, pass-over humidifiers and heater wire humidifiers are preferable.

REF: p. 170

12. Which of the following considerations is most important when using a large-volume nebulizer to provide oxygen and humidification to an infant in an incubator? a. Meeting the inspiratory flow demands of the infant b. Supplying the infant with adequate humidification c. Delivering sufficient oxygen to meet the infant’s needs d. Preventing a high noise level from developing

ANS: D

Caution should be exercised when using LVNs with incubators or hoods because of the noise produced. The American Academy of Pediatrics recommends a sound level less than 58 dB to avoid hearing loss in patients in incubators and hoods. Many LVNs are designed to deliver controlled concentrations of oxygen and use a Venturi system to entrain air into the stream of gas administered to the patient. Standard entrainment nebulizers may deliver a fractional concentration of delivered oxygen approaching 1.00 but cannot provide a fractional concentration of inspired oxygen (FiO2) greater than 0.40. High-flow nebulizers are designed to deliver high-flow rates of oxygen, bringing the FiO2 up to 0.60 to 0.80. Closed dilution and gas injection nebulizers provide high-flow access to the nebulizer from two gas sources, allowing gas to mix without compromising FiO2.

REF: p. 170

13. Which of the following nebulizers should be suggested to improve lung dose in patients undergoing invasive mechanical ventilation? a. Jet nebulizer b. Ultrasonic nebulizer c. Breath-actuated nebulizer d. Vibrating mesh nebulizer

ANS: D

Because the VMN does not add gas to the patient airway or ventilator circuit, greater aerosol concentrations can be reached than with jet nebulizers. VMNs produce the same size aerosol particles with air, oxygen, or helium. Handheld VMN nebulizers tend to be much more efficient than continuous jet nebulizers or USNs, with inhaled mass ranging from 25% to 55%. When used with mechanical ventilators, VMNs do not change volumes or flows.

REF: p. 172 b. Use a valved holding chamber. c. Depress the nozzle only half the full distance. d. Instruct the patient to inspire a short, rapid breath.

14. How can a patient avoid the problem of terminating inhalation when a plume from a pressurized metered-dose inhaler (pMDI) impacts the oropharynx? a. Hold the pMDI closer the mouth.

ANS: B

A “cold Freon effect” can occur when the aerosol plume from a pMDI reaches the back of the mouth and the patient stops inhaling. This problem can be corrected by using a valved holding chamber connected to the pMDI. A valved holding chamber, which has a volume usually between 140 and 750 mL, enables the plume from a pMDI to expand. It incorporates a oneway valve that permits the aerosol to be drawn from the chamber during inhalation only, diverting the exhaled gas to the atmosphere and not disturbing the aerosol remaining in suspension in the chamber.

REF: p. 175

15. Which of the following functions are served by spacer and holding chambers in conjunction with pMDIs?

I. Reduction in oropharyngeal deposition of drug

II. Elimination of the “cold Freon effect”

III. Improvement in lower respiratory tract depositionIV. Decrease in treatment time without sacrificing efficacy a. I and III only b. II and IV only c. I, II, and III only d. I, III, and IV only

ANS: C

Spacers and valved holding chambers (1) reduce oropharyngeal deposition of drug, (2) relieve the bad taste of some medications by reducing oral deposition, (3) eliminate the cold Freon effect, (4) decrease aerosol mass median aerodynamic diameter, (5) increase respirable particle mass, (6) improve lower respiratory tract deposition, and (7) significantly improve therapeutic effects.

REF: p. 175 a. To provide better lung deposition b. To increase the dose of the medication c. To enable the patient to take a deeper breath d. To reduce the risk of oral yeast infections

16. Why should pMDIs containing steroids in particular be used with a valved holding chamber?

ANS: D

Valved holding chambers reduce the pharyngeal dose of aerosol from the pMDI 10- to 15-fold over administration without a holding chamber. Using a valved holding chamber decreases total body dose from swallowed medications, which is an important consideration with steroid administration. The high percentage of oropharyngeal drug deposition with steroid pMDIs can increase the risk of oral yeast infections (thrush). Rinsing the mouth after steroid inhalation can reduce this problem, but most pMDI steroid aerosol impaction occurs deeper in the pharynx, which is not easily rinsed. For this reason, steroid pMDIs should always be used in combination with a valved holding chamber.

REF: pp. 175-176

17. For which of the following types of patients would using a dry powder inhaler (DPI) for medication delivery likely be contraindicated? a. A 4-year-old child b. A patient with COPD c. A teenager able to generate an inspiratory flow of 40 L/min d. An 11-year-old diagnosed with stable asthma

ANS: A

At present, DPIs may be considered alternatives to pMDIs for patients who can generate inspiratory flow rates greater than 30 to 60 L/minute but who are unable to use pMDIs effectively. DPIs are recommended for therapy for patients with stable asthma and chronic obstructive pulmonary disease but not for patients with acute bronchoconstriction or children less than 6 years of age.

REF: p. 179

18. The physician in the emergency department is attending to a 12-year-old child who has an exacerbation of asthma. The physician asks the therapist to recommend a medication that has a synergistic effect with beta-2 agonists during asthma exacerbations. Which of the following medications should the therapist recommend? a. Montelukast b. Ipratropium bromide c. Fluticasone d. Triamcinolone

ANS: B

Although beta-2 agonists are the first-line agents for treating an exacerbation of asthma, data in both adults and children suggest that ipratropium bromide is synergistic with beta-2 agonists for the therapy of acute asthma. Combination bronchodilator therapy using albuterol and ipratropium in patients with severe asthma significantly reduces the percentage of patients hospitalized.

REF: p. 181

19. An 18-month-old patient brought to the emergency department is exhibiting signs and symptoms consistent with an acute asthma episode and is administered a beta-2 agonist to which the patient does not respond favorably. Which of the following conditions could be responsible for this patient’s problem? a. Aspiration of a foreign object b. Croup c. Bronchiolitis d. Pneumonia

ANS: A

Poor relief of acute asthma with bronchodilators may signify a nonasthmatic cause of wheezing, such as foreign body aspiration or tracheitis. Infants with bronchiolitis respond poorly to bronchodilator medications, which are therefore not recommended for this condition.

REF: p. 181 a. Between the “y” adapter and the endotracheal tube b. 30 cm from the ETT in the inspiratory limb c. 30 cm from the heated humidifier d. In the expiratory limb

20. Where in the ventilator circuit should a continuous jet nebulizer be placed to improve efficiency of aerosol delivery?

ANS: B

Placement of a continuous jet nebulizer 30 cm from the ETT is more efficient than placement between the patient “y” adapter and the ETT because the inspiratory ventilator tubing acts as a spacer for the aerosol to accumulate between inspirations.

REF: p. 183

21. The therapist receives an order to administer a bronchodilator in-line to an infant receiving mechanical ventilation. The order also indicates that the nebulizer must not significantly increase the patient’s delivered tidal volume. Which of the following aerosol delivery devices should the therapist select?

I. Vibrating mesh nebulizer

II. pMDI

III. Jet nebulizerIV. Ultrasonic nebulizer a. II and III only b. I, II, and IV only c. I, III, and IV only d. II, III, and IV only

ANS: B

In both adults and infants, the gas driving the jet nebulizer enters the ventilator circuit with the potential for changing delivered volumes, pressures, and parameters; this can set off alarms. Because of the relatively low flow rates used in infant ventilator circuits, the addition of 2 to 6 L/minute of gas can more than double the delivered volume. With other aerosol generators such as pMDIs and ultrasonic and vibrating mesh nebulizers, there is no substantial increase in gas volume and ventilator parameters remain consistent.

REF: pp. 185-186

22. Which of the following methods is acceptable for delivering a drug via a pMDI to an intubated neonate receiving mechanical ventilation? a. In-line with the ventilator b. Through a resuscitation bag c. Through a T-piece d. In-line with a spacer

ANS: B

The administration of medication by pMDI to the mechanically ventilated neonate may not be well tolerated. Leaving a chamber device in-line is not practical because of the increased compressible volume incorporated into the ventilator circuit. Depending on the FiO2 and the propellant gas volume, an in-line pMDI actuation theoretically may result in the delivery of a hypoxic gas mixture to an infant receiving a tidal volume less than 100 mL. It is possible to deliver a pMDI aerosol medication to the intubated neonate, especially for medications available only in pMDI preparations. However, it may be preferable to hand-ventilate the pMDI delivery of medication to the patient. If a chamber adapter is used, the infant must be removed from the circuit, the chamber placed in-line, and the infant reattached to the circuit before the pMDI is administered. The large dead-space volume caused by placing a spacer or chamber at the end of the ETT must also be considered when administering pMDI medications to an infant.

REF: p. 186