Mech Vent Ch 18 Wkbk

Front 1

Define the term problem.

Back 1

A problem is a situation in which one finds discord or in which one is uncomfortable and does not have an immediate solution.

Front 2

Define troubleshooting in the context of mechanical ventilation.

Back 2

Troubleshooting, in the context of mechanical ventilation, is the identification and resolution of technical malfunctions in the patient-ventilator system. It involves purposefully resolving inappropriate and potentially dangerous situations.

Front 3

When responding to an activated ventilator alarm, what is the respiratory therapist's first priority?

Back 3

Patient safety is the respiratory therapist’s first priority. The RT needs to make sure that the patient is adequately ventilated and oxygenated.

Front 4

To establish the respiratory therapist's first priority, what assessments must be made?

Back 4

Immediate steps to assess the patient include (1) check and silence the alarm; (2) visually assess the patient’s level of consciousness, color, use of accessory muscles, and chest wall movement; (3) listen for breath sounds; (4) obtain a pulse oximetry reading; and (5) measure the pulse.

Front 5

If a serious ventilatory problem is detected, what should the respiratory therapist's next step be?

Back 5

The respiratory therapist should disconnect the patient from the ventilator and begin manual ventilation with a resuscitation bag.

Front 6

What are the advantages and disadvantages of manually ventilating a patient when a problem is detected?

Back 6

Advantages of disconnecting the patient and manually ventilating are (1) insurance that the patient is being ventilated; (2) ability to assess (feel) the patient’s lung compliance and airway resistance; and (3) ability to determine whether the problem lies with the patient or the ventilator. Disadvantage include (1) increased risk of barotrauma because of inappropriate patterns of ventilation and excessive pressures; (2) derecruitment of the lungs when PEEP is lost, leading to desaturation; and (3) increased risk of ventilator-associated pneumonia from contamination of the airways.

Front 7

List the physical signs of distress that a patient receiving mechanical ventilation might exhibit.

Back 7

Retraction of the suprasternal, supraclavicular, and intercostal spaces; accessory muscle use; nasal flaring; hypotension; arrhythmias; tachycardia; diaphoresis; abnormal movement of the thorax and abdomen; tachypnea; and abnormal breath sounds.

Front 8

What equipment, techniques, or data can be used to help identify the cause of a patient's sudden distress while being mechanically ventilated?

Back 8

Pulse oximeter, capnograph readings, ventilator graphics, PIP, Pplateau, and exhaled volumes.

Front 9

List six patient-related causes of sudden respiratory distress that originate within the patient's lungs.

Back 9

(a) Bronchospasm, (b) secretions, (c) pulmonary edema, (d) pulmonary embolus, (e) dynamic hyperinflation, and (f) pneumothorax.

Front 10

List six nonpulmonary patient-related causes of sudden respiratory distress.

Back 10

(a) Artificial airway problems, (b) abnormal respiratory drive, (c) alteration in body posture, (d) drug-induced problems, (e) abdominal distention, and (f) anxiety.

Front 11

List the six types of patient-ventilatory asynchrony that can cause sudden respiratory distress.

Back 11

Patient-ventilator asynchrony may be caused by (a) inappropriate ventilatory support mode, (b) inappropriate trigger sensitivity, (c) inappropriate inspiratory flow setting, (d) inappropriate cycle variable, (e) inappropriate PEEP setting, and (f) problems with closed-loop ventilation.

Front 12

Aside from patient-ventilator asynchrony, what ventilator-related issues can cause sudden respiratory distress in patients?

Back 12

System leaks, circuit malfunctions and inadequate FIO2.

Front 13

How can the respiratory therapist distinguish the difference between sever distress caused by a ventilator related or patient-related problem?

Back 13

When the patient is in severe distress, disconnecting the person from the ventilator and ventilating the individual manually allows the respiratory therapist to distinguish the cause of the distress. If the patient’s distress immediately goes away, the problem is with the ventilator. If the distress does not subside, the problem is with the patient experiencing anxiety or pain.

Front 14

Describe the seven steps needed to manage sudden severe distress in a ventilator-supported patient.

Back 14

(a) Disconnect the patient from the ventilator; (b) initiate manual ventilation with a manual resuscitation bag using 80% to 100% supplemental oxygen, maintain normal ventilating pressures and using a PEEP attachment if the patient has been on PEEP ≥ 10 cm H2O; (c) manually evaluate compliance and resistance through bag ventilation; (d) perform a rapid physical examination and assess monitored indices and alarms; (e) check the patency of the airway by passing a suction catheter; (f) if death appears imminent, consider and treat most likely causes (i.e., pneumothorax, airway obstruction); and (g) once the patient’s condition has been stabilized, perform a more detailed assessment and management.

Front 15

An oral ET should be approximately at what mark for men and for women? What are the appropriate ranges for each?

Back 15

Measuring at the teeth, an endotracheal tube should measure approximately 23 cm (22 to 24 cm) for men and approximately 21 cm (20 to 22 cm) for women.

Front 16

What steps should be taken if a suction catheter cannot be passed down the ET of a patient in severe respiratory distress (patient is not biting the tube)?

Back 16

The cuff should be deflated to allow air movement around the tube if the patient is breathing spontaneously. The next step would be to remove the ET tube, ventilate with a resuscitation bag, and reintubate as soon as possible.

Front 17

What clinical manifestation should a respiratory therapist look for when a tension pneumothorax is suspected during positive pressure ventilation?

Back 17

A patient with a pneumothorax shows use of accessory muscles, uneven chest wall movement, absence of breath sounds on the affected side, hyperresonance percussion on the affected side, tracheal deviation away from the affected side, and an increase in the Pplateau and peak pressures.

Front 18

If a tension pneumothorax is strongly suspected and cardiopulmonary arrest is imminent, what action should be taken?

Back 18

A 14- or 16-gauge needle should be inserted into the second intercostal space at the midclavicular line over the top of the rib on the affected side.

Front 19

What signs suggest that a patient is experiencing bronchospasm while receiving mechanical ventilation?

Back 19

Bronchospasm should be suspected when a patient shows dyspnea; wheezing; accessory muscle use (increased WOB); paradoxical chest and abdominal movement; retractions of the suprasternal, supraclavicular, and intercostal spaces; and increased peak inspiratory and transairway pressures (PIP – Pplateau).

Front 20

What other patient problems can cause wheezing?

Back 20

Wheezing is associated with pulmonary emboli and cardiogenic problems.

Front 21

How can problems due to secretions be minimized during mechanical ventilation?

Back 21

Secretion problems may be prevented by providing warmed, humidified gas to the patient and suctioning when indicated. Bronchial hygiene, including postural drainage and percussion, as well as therapeutic bronchoscopy, may be performed.

Front 22

What is the difference in onset between cardiogenic and noncardiogenic pulmonary edema?

Back 22

Cardiogenic pulmonary edema can occur suddenly. Noncardiogenic pulmonary edema, or ARDS, usually develops over a day or two and is not a sudden-onset problem.

Front 23

How does auto-PEEP affect the flow-time scalar and the flow-volume loop?

Back 23

Auto PEEP prevents the flow on a flow-time scalar and on a flow-volume loop from returning to baseline.

Front 24

List conditions that may stimulate the respiratory center output.

Back 24

Pain, anxiety, increased peripheral sensory receptor stimulation, medications, increased ventilatory needs, and inappropriate ventilator settings.

Front 25

Describe how the presence of abdominal distention can cause atelectasis, ventilation/perfusion abnormalities, and hypoxemia?

Back 25

Abdominal distention causes upward pressure on the diaphragm, restricting its downward movement. This restriction of the diaphragm’s movement can lead to atelectasis in the basilar areas of the lungs, ventilation/perfusion abnormalities, and hypoxemia.

Front 26

The rapid onset of hypoxemia, tachycardia, tachypnea, and hypertension, along with a decrease in end-tidal CO2, is indicative of what type of patient problem? How can this problem be confirmed and treated?

Back 26

These are the clinical manifestations of a pulmonary embolism. Pulmonary embolism can be confirmed with a pulmonary angiogram and computerized tomography. It is treated with thrombolytic therapy.

Front 27

What are the common sites for leaks to occur in the patient-ventilator system?

Back 27

Leaks are often present around the endotracheal tube cuff and at junctions in the patient circuit where connections exist, including water traps, HME or humidifiers, in-line suction catheters, temperature probes, in-line metered-dose inhaler chambers, proximal airway pressure lines, capnograph sensors, and exhalation valves.

Front 28

How is a manual leak test performed on a ventilator connected to a patient?

Back 28

While the patient is ventilated manually, the clinician changes the ventilator mode to VC-CMV and sets the VT to 100 mL, the flow to 20 L/min, the inspiratory pause to 2 seconds, and the pressure limit to maximum. The patient Y-connector is occluded with sterile gauze, and the ventilator is cycled manually. The circuit pressure that develops during inspiration should plateau and hold at that level, falling no more than 10 cm H2O during a 2-second pause. If the pressure falls more than this, a significant leak is present and must be corrected. If the leak cannot be corrected quickly and easily, a change of equipment may be necessary.

Front 29

List six causes of trigger asynchrony.

Back 29

(a) Incorrect sensitivity setting, (b) low flow settings, (c) poorly responsive internal demand valve, (d) external gas source−powered nebulizer in-line, (e) water in the inspiratory line, and (f) auto PEEP.

Front 30

List at least four common causes of a low-pressure alarm situation.

Back 30

The low pressure alarm may be caused by (any of the following)) patient disconnection, leaks in the ventilator circuit, airway leaks, chest tube leaks, and disconnection of the inspiratory or expiratory tubing of the ventilator circuit.

Front 31

List nine common causes of a high-pressure alarm situation.

Back 31

High pressure alarms may be caused by airway-related problems, such as (a) secretions or mucus; coughing; patient biting the tube; or (b)tube migration into the right mainstem bronchus. Lung conditions that may lead to high pressure alarms include (c)increased airway resistance from bronchospasm, (d) mucosal edema or secretions, (e) decreased compliance from a pneumothorax or pleural effusion, and (f) patient-ventilator asynchrony. Other causes of high pressure alarms include (g) accumulation of condensate in the patient circuit, (h) kinking of the inspiratory circuit, or (i) malfunction of the inspiratory or expiratory valves.

Front 32

If the peak inspiratory pressure (PIP) is 30cm H2O, what should the low- and high-pressure alarms be set at?

Back 32

PIP = 30 cm H2O; low pressure alarm setting = 20 to 25 cm H2O; and high pressure alarm setting = 40 cm H2O.

Front 33

Name two conditions that would trigger a low PEEP/CPAP alarm?

Back 33

A low PEEP/CPAP alarm could be triggered by (a) a leak in the circuit for which the ventilator is not compensating and (b) active inspiration by the patient that drops the pressure below the alarm threshold.

Front 34

List five potential causes for triggering an apnea alarm.

Back 34

Apnea alarms can be caused by (a) patient apnea, (b) patient disconnect, (c) system leaks, (d) inadequate machine sensitivity, and (e) inappropriately set apnea parameters.

Front 35

List two potential causes for triggering a low-source gas pressure alarm.

Back 35

(a) Disconnected high pressure line, (b) source gas failure.

Front 36

Name two potential causes for a power-input alarm.

Back 36

(a) Loss of power, (b) machine not connected to an emergency power outlet during a power test.

Front 37

What is the most likely cause of a ventilator inoperative alarm?

Back 37

A “Vent Inop” alarm is triggered by an internal malfunction, which usually is detected by the ventilator’s self-testing systems.

Front 38

Describe the alarm situations and ventilator graphics that a leak in the patient-ventilator system would cause.

Back 38

A leak in a patient-ventilator system may cause low pressure, low volume, low minute volume, and apnea alarms to sound. On a volume-time scalar, the volume would not drop to zero at the end of the breath. On a volume-pressure loop and flow-volume loop, the volume would not return to zero.

Front 39

What types of graphics will allow the respiratory therapist to detect inadequate flow?

Back 39

Simultaneously looking at the flow-time and pressure-time scalars can alert the respiratory therapist to inadequate flow. With inadequate flow, the flow curve is constant and the pressure-time graphic is concave.

Front 40

The phenomenon caused by the oscillation of air in the patient-ventilator circuit and at the upper airway at the beginning of inspiration is known as:

Back 40

ringing, spiking, or overshooting

Front 41

What can be done to alleviate the problem caused by the phenomenon in the previous question?

Back 41

The gas flow and pressure delivery at the beginning of the breath can be adjusted with the inspiratory rise time parameter.

Front 42

Name three problems that may cause the expiratory portion of the volume-time curve to go below baseline.

Back 42

(a) Air trapping, (b) an active exhalation, or (c) a flow sensor out of calibration may cause the expiratory portion of the volume-time curve to fall below baseline.

Front 43

How does an externally powered nebulizer affect ventilator function?

Back 43

An externally powered nebulizer can block the machine’s ability to sense a patient’s inspiratory effort and increase tidal volume delivery.

Front 44

A leak in the endotracheal tube cuff will cause which alarms to be activated?

Back 44

An ET tube cuff leak may cause activation of the low pressure, low PEEP/CPAP, low tidal volume, or low minute volume alarm.

Front 45

How can a pulmonary empobism be detected during mechanical ventilation?

Back 45

A pulmonary embolus should be suspected when a decrease in the end-tidal CO2 value is seen compared with previous values. A widening of the arterial-to-end-tidal partial pressure CO2 gradient also will be noted.

Front 46

During mechanical ventilation with pressure controlled-continuous mandatory ventilation (PC-CMV), the low tidal volume alarm becomes activated on every breath; there is no leak in the system. What could be the cause of this alarm?

Back 46

The reduced volume delivery while in pressure control is most likely because of a decrease in lung compliance and/or an increase in airway resistance.

Front 47

How can a respiratory therapist determine the cause of an increasing peak inspiratory pressure?

Back 47

In addition to the peak inspiratory pressure, the respiratory therapist needs to measure the Pplateau. An increase in the transairway pressure indicates an increase in airway resistance, whereas an increase in both PIP and Pplateau, with a constant PTA, is evidence of decreasing lung compliance.

Front 48

What type of asynchrony most commonly occurs during pressure support ventilation?

Back 48

Cycle dyssynchrony

Front 49

How can the asynchrony form the previous question be detected on ventilatory graphics?

Back 49

There would be a slight elevation of pressure at the end of inspiration on a pressure-time scalar. This is actually active exhalation.

Front 50

What type of problem would cause a high pressure alarm to become activate intermittently?

Back 50

An intermittent high pressure alarm may be activated by patient coughing or biting of the ET tube.

Front 51

What type of problem should the respiratory therapist suspect when a ventilator patien exhibits sudden respiratory distress and a suction catheter cannot be passed throgh the endotracheal tube? What action should be taken?

Back 51

The ET tube could be completely blocked with mucus, or the patient could be biting the ET tube. If the ET tube is completely blocked, it must be changed. If the patient is biting the ET tube, a bite block needs to be inserted

Front 52

What steps can be taken to decrease auto-PEEP?

Back 52

Suction the airway, administer bronchodilator therapy, allow more time for exhalation by increasing the flow rate or decreasing the inspiratory time, decrease the minute ventilation, or increase the ET tube size if appropriate.

Front 53

What situations can cause the I:E ratio indicator and alarm to be activated?

Back 53

The I:E ratio indicator and alarm is activated when the I:E ratio is greater than 1:1. This may be caused by increased airway resistance, decreased lung compliance, or an inadequate flow setting for the desired tidal volume delivery.

Front 54

A respiratory therapist responding to a ventilator alarm finds that the high respiratory rate alarm is activated. The ventilator is set to VC-CMV rate 12. What are some possible reasons for this activated alarm?

Back 54

The ventilator could be autotriggering; the patient’s metabolism could have increased; the alarm may be set inappropriately; or the patient could be hypoxemic.