Ventilator Troubleshooting: Overview and Practice Questions

It’s inevitable that, while working with a mechanical ventilator, you will eventually experience a problem. This is when ventilator troubleshooting comes in handy.

By knowing the most common problems that can occur, and how to troubleshoot them, you can ensure that your patient is receiving the ventilatory support that they need.

In this article, we will go over some of the most common problems that occur during mechanical ventilation, and how to promptly solve them.

What is Ventilator Troubleshooting?

Ventilator troubleshooting is the process of identifying and solving a problem that occurs in the patient-ventilator connection. This is important because, when a problem occurs, it can cause the patient to experience discomfort, or even put their life at risk.

The goal of ventilator troubleshooting is to quickly identify the problem and then take the necessary steps to solve it. This process requires extensive knowledge and understanding of the principles of mechanical ventilation.

Mechanical Ventilation Problems

In a perfect world, the delivery of mechanical ventilatory support would be flawless, and we would never experience any problems. However, of course, this is not the case.

There are various problems that can occur during mechanical ventilation, including the following:

• Respiratory distress
• Ventilator alarms
• System leaks
• Circuit disconnection
• Inadequate oxygenation
• Patient-ventilator asynchrony
• Artificial airway problems
• Secretion buildup
• Auto-PEEP
• Accidental extubation

Respiratory Distress

When a patient on the ventilator experiences a problem, one of the first signs you’ll see is respiratory distress. This includes:

• Tachypnea
• Tachycardia
• Nasal flaring
• Diaphoresis
• Paradoxical thoracic movement
• Arrhythmias
• Dyspnea on exertion
• Accessory muscle usage while breathing
• Pursed-lip breathing
• Absent cough

When you notice one or more of these symptoms, especially when accompanied by the sounding of a ventilator alarm, it’s a sure sign that something is wrong and you need to take action.

Ventilator Alarms

Ventilator alarms serve as a safety mechanism and use a set of parameters to provide alerts whenever a problem arises in the patient-ventilator interaction. The alarms may be audible, visual, or both, depending on the ventilator mode and settings.

There are several different types of alarms that may sound whenever a problem arises, including:

• High pressure
• Low pressure
• Low volume
• High frequency
• Apnea
• High PEEP
• Low PEEP

Check out our full ventilator alarms guide to learn about the causes and solutions to each type of alarm.

System Leaks

A system leak occurs when there is a disconnection, a problem with the circuit, or a problem with the artificial airway. Some signs of a leak during mechanical ventilation include:

• Low pressure alarm
• Low volume alarm
• Low minute ventilation alarm
• Abnormal ventilator graphics

If the leak is due to a disconnection, you’ll simply need to reconnect the circuit. If the problem is with the artificial airway, you may need to check the cuff pressure and add more air to the cuff. Otherwise, you’ll need to replace the artificial airway.

Inadequate Oxygenation

If the patient is not receiving enough oxygen, the low-SpO2 alarm will sound. In this case, an arterial blood gas (ABG) should be analyzed to confirm that hypoxemia is present. Then you can adjust the FiO2 or PEEP settings accordingly, depending on the patient’s needs.

Refractory hypoxemia is another oxygenation problem that can occur during mechanical ventilation in severe cases.

This is when the patient’s SpO2 doesn’t increase despite a high FiO2 setting. This is often a sign of acute respiratory distress syndrome (ARDS) and requires treatment with high levels of PEEP.

Patient-Ventilator Asynchrony

Ventilator dyssynchrony is characterized by inappropriate timing of a delivered breath between a patient and the mechanical ventilator. This increases the work of breathing and makes it more difficult for the patient to breathe comfortably on the ventilator.

Correcting ventilator dyssynchrony depends on the specific cause of the problem. It usually involves inappropriate ventilator settings; therefore, making proper adjustments is the best treatment method.

For example, you may need to adjust the flow, sensitivity, or inspiratory time. Or, you may consider using a different ventilator mode. The less control the ventilator has on the patient’s respiratory pattern, the less likely they will experience dyssynchrony.

Artificial Airway Problems

Several problems can occur during mechanical ventilation when using an artificial airway, including:

• Disconnection
• Cuff leak
• Obstruction
• Incorrect placement
• Malfunctioning valve
• Tube kinking
• Tube biting

If a serious problem arises with an artificial airway, the patient should be disconnected and manually ventilated with a bag-valve mask.

However, if the tube is fully obstructed, it must be removed to deliver manual breaths. This requires reintubation with a new endotracheal tube.

Secretion Buildup

Airway suctioning is required during mechanical ventilation to avoid the accumulation of excess mucus and secretions. This typically involves the use of an in-line suction catheter that is connected directly to the endotracheal tube.

Copious secretions may occur in conditions such as pulmonary edema, cystic fibrosis, bronchiectasis, and respiratory infections.

Suctioning should only be performed when indicated, and the patient may also benefit from receiving warmed and humidified air. Other types of airway clearance therapy, such as chest physiotherapy (CPT), may also be used to help clear secretions.

Auto-PEEP

Auto-PEEP is a complication of mechanical ventilation that occurs when a positive pressure remains in the alveoli at the end-exhalation phase of the breathing cycle.

This can result in patient-ventilator asynchrony, making it uncomfortable for the patient to breathe while on the machine.

A high-PEEP alarm may sound whenever auto-PEEP or air trapping is present. It is corrected by prolonging the expiratory time.

Accidental Extubation

Accidental extubation occurs when the endotracheal tube is inadvertently removed from the patient’s trachea. This includes self-extubation, which is the deliberate removal of the tube by the patient.

An unplanned extubation is a serious complication in patients reliant on high levels of ventilatory support.

It can be prevented by properly securing the artificial airway in place with tape or a tube holder. The patient should also be monitored closely for any signs of agitation or distress.

Ventilator Troubleshooting Practice Questions:

1. What technical problems may occur during mechanical ventilation?
System leak, circuit malfunction, disconnection, inadequate FiO2, patient-ventilator asynchrony, inappropriate ventilator mode, and inappropriate ventilator settings

2. What are the steps for solving a problem during mechanical ventilation?
(1) Analyze the situation, (2) Gather and assess related data, (3) Search for possible solutions, (4) Consider the ramifications of possible solutions, (5) Attempt solution and observe the patient’s response, (6) Determine if the problem is solved, and (7) If not, try a different solution.

3. What should the respiratory therapist confirm when responding to a ventilator alarm?
They must confirm that the patient is receiving adequate ventilation and oxygenation.

4. What steps can be used to protect a patient when a problem occurs during mechanical ventilation?
(1) Respond to the alarm and (2) Ensure the patient is adequately ventilated, and (3) Ensure the patient is adequately oxygenated.

5. What should a respiratory therapist assess during ventilator troubleshooting?
They should observe the patient for chest rise and fall, access the artificial airway, access the patient’s breathing, perform auscultation, check for a disconnection, and check for a system leak.

6. What should the respiratory therapist visually asses during ventilator troubleshooting?
They should visually assess the patient’s level of consciousness, color, and accessory muscle usage.

7. If a problem can be quickly identified and rectified, what should the respiratory therapist do?
The respiratory therapist can proceed cautiously but must continue to closely monitor the patient.

8. If a problem cannot be quickly identified and rectified, what should the respiratory therapist do?
They should immediately remove the patient from the ventilator and initiate manual ventilation with a resuscitation bag.

9. What patient-related problems can occur during mechanical ventilation?
Artificial airway problems, bronchospasm, excessive secretions, pulmonary edema, pulmonary embolus, auto-PEEP, abnormal respiratory drive, change in body posture, drug-induced problems, abdominal distention, pneumothorax, and anxiety

10. What artificial airway problems can occur during mechanical ventilation?
Tube migration, rupture or leakage of the cuff, kinking or biting of the ET tube, secretion buildup or mucus plugging of airways, cuff herniation over the end of the ET tube, trauma to the carina by the ET tube, tracheal fistula, and separation of 15 mm airway adaptor from ET tube

11. What is tube migration?
This occurs due to neck flexion or extension, which can move the tube 2 cm above the vocal cords or into the right main stem bronchus.

12. How can you solve kinking or biting of the endotracheal tube?
You can insert an oropharyngeal airway if the patient is biting the tube. If kinking is occurs, it may require removal and replacement.

13. How can you rectify secretion or mucus plugging problems?
You can suction the patient’s airway and begin using a heated humidifier.

14. How can you fix cuff herniation over the end of an endotracheal tube?
Deflate the cuff

15. What should you do if the patient cannot be mechanically or manually ventilated?
In this case, it likely means that an obstruction is present. Therefore, you can try passing a suction catheter through the tube. If it will not pass, it confirms an obstruction. This means that you must deflate the cuff, remove the tube, and begin delivering manual breaths until reintubation can occur.

16. What risks are associated with the delivery of positive pressure?
Barotrauma and a pneumothorax

17. What are the signs of a pneumothorax during mechanical ventilation?
Increased work of breathing, increased accessory muscle usage, uneven chest wall movement, absence of breath sounds on the affected side, and a tracheal shift to the unaffected side

18. What immediate treatment must be used for a tension pneumothorax?
Chest tube insertion into the 2nd intercostal space at the midclavicular line

19. What should you do if a mechanically ventilated patient experiences secretion buildup?
Suction when indicated, monitor the thickness, color, and amount of mucus, add heated humidification if thickening occurs, and send a sputum sample to the lab for testing

20. What is dynamic hyperinflation also known as?
Auto-PEEP

21. What problems can occur when changing a patient’s body position during mechanical ventilation?
It can cause an accidental extubation, disconnection, or kinking of the ventilator circuit.

22. What causes drug-induced distress during mechanical ventilation?
It is caused by chemical dependencies (e.g., drugs, alcohol) and may result in restlessness, irritability, and insomnia.

23. What is refractory hypoxemia?
It is a type of hypoxemia that does not improve with a high FiO2 setting, which means that it must be treated with high levels of PEEP.

24. What are the causes of patient-ventilator dyssynchrony?
Improper mode selection, inappropriate trigger sensitivity setting, inappropriate inspiratory flow setting, inappropriate cycle variable, and inappropriate PEEP

25. What alarms typically sound in the presence of a leak?
The low-pressure and low volume alarms

26. Where do most leaks occur during mechanical ventilation?
Most leaks occur around the ET tube cuff; however, they may also occur near the humidifier/HME, water trap, in-line suction catheter, or temperature probe.

27. What occurs when the patient is set up on an inappropriate mode of ventilation?
It may cause the patient to have increased work of breathing.

28. What should you assess when the low-pressure alarm is sounding?
You must check for a disconnection or leak. You should also check the proximal pressure line to make sure it is connected and unobstructed.

29. A low-pressure alarm is often accompanied by what other alarms?
Low minute ventilation or low tidal volume

30. What causes the high-pressure alarm to sound?
Some common causes include coughing, secretion buildup, obstructions, or when a patient is biting the ET tube. It may also sound when the airway resistance has increased, or when the lung compliance has decreased.

31. What is the apnea alarm used for?
It is used to determine whether or not the patient is apneic.

32. What should you do if the low source gas pressure alarm sounds?
You should ensure that a 50 psi gas source is available, and check the high-pressure hoses that are connected to the ventilator.

33. What causes the I:E ratio alarm to sound?
It typically sounds when there is a problem with the flow and usually indicates that the I:E ratio is greater than 1:1.

34. What should you do if the I:E ratio alarm goes off?
Check for increased airway resistance or decreased lung compliance and treat the underlying cause.

35. How can you solve an I:E ratio problem in a volume-controlled mode?
Increase the inspiratory flow

36. What would cause the high PEEP alarm to sound?
The causes are similar to those of the high-pressure alarm, which include coughing, secretions, biting the tube, increased airway resistance, and decreased lung compliance.

37. What would cause the low tidal volume, minute ventilation, or respiratory rate alarm to sound?
The causes are similar to those of the low-pressure alarm, which include a patient disconnection, leak, or obstruction.

38. What should you do if the high tidal volume, minute ventilation, or respiratory rate alarms sound?
Check the machine sensitivity for auto-triggering and ensure the alarm parameters are set correctly. If using an external nebulizer, reset the alarms until the breathing treatment is complete.

39. What should you do if the low or high FiO2 alarms sound?
Check the gas source to confirm that the gas analyzer is functioning properly.

40. What are the signs and symptoms associated with patient-ventilator asynchrony?
Use of accessory muscles to breathe, pursed-lip breathing, minimal or absent cough, tripoding, barrel chest, digital clubbing, dyspnea on exertion, tachypnea, and tachycardia.

41. How can a nebulizer powered by an external gas source affect ventilator function?
It can cause high tidal volume delivery and increased work to trigger a breath.

42. What would you see in the presence auto-PEEP when looking at the ventilator graphics?
The flow-time curve would show that the peak expiratory flow does not return to the baseline before the next breath. When looking at the volume-time curve, during the expiratory phase, the tidal volume does not return to the baseline before the next breath.

43. What potential problems are associated with using a heated humidification system during mechanical ventilation?
The drying of secretions due to inadequate humidification.

44. How can you visually notice a system leak?
By looking at the ventilator graphics

45. What should you do if the low-SpO2 alarm is sounding?
Order an ABG to confirm that hypoxemia is present

46. What is accidental extubation?
It occurs when the endotracheal tube is inadvertently removed from the patient’s trachea.

47. What diseases can decrease lung compliance during mechanical ventilation?
ARDS, pneumothorax, and CHF

48. What can increase airway resistance during mechanical ventilation?
Secretions and bronchospasm

49. How can you treat bronchospasm in a mechanically ventilated patient?
By administering a bronchodilator agent via nebulizer, such as albuterol

50. What should you do if an unknown problem arises while a patient is on the ventilator?
You must make sure that the patient is ventilating and oxygenating. If you are unsure, you must disconnect the patient and begin delivering manual breaths until the problem is identified and solved.

Final Thoughts

Ventilator troubleshooting involves the identification and correction of problems that can occur during mechanical ventilation. This includes patient-ventilator asynchrony, artificial airway issues, secretion buildup, and auto-PEEP.

When a problem occurs, you will likely notice the patient showing signs of respiratory distress. This will cause ventilator alarms to sound, which are designed to alert medical professionals when a problem arises in the patient-ventilator interaction.

Respiratory therapists must understand how to troubleshoot these problems quickly and efficiently to provide the best possible care for their patients. Hopefully, this guide has given you a better understanding of how to do just that. Thanks for reading!