Introduction to Ventilator Settings

As a nurse, it is important to understand and be able to choose the proper settings for ventilation. Nursing responsibilities include assessing and watching the client’s condition while on a ventilator. Other Important factors include keeping the client safe and comfortable while operating this life-sustaining device.

There are different types of ventilators (with some having more advanced capabilities), such as having the ability to monitor blood gases or CO2 levels.

Ventilator Settings Explained (with Normal Lab Values)

In practice, it can be easy to misunderstand certain ventilator settings. It’s a nursing responsibility to be competent in maintaining proper and accurate ventilator settings. Competency is key.

Respiratory Rate

The respiratory rate is a measurement of how many times per minute a person exhales and inhales. The client’s respiratory rate is often used as a marker of their overall level of comfort, so nurses must know how to use this setting on the ventilator.

On most ventilators, nurses can adjust the respiratory rate by pressing the “Respiratory Rate” button on the device, then using the up or down arrow keys to increase or decrease the number displayed on the screen.

Normal range: 12–20 breaths per minute

Inspiratory Flow Rate

The inspiratory flow rate is a setting on a ventilator used to control the amount of air that gets pushed into a client’s lungs. It can be adjusted depending on their needs and their condition.

If you set the inspiratory flow rate too low, your client might need more oxygen. But if you set it too high, they might get too much oxygen, which can cause them to feel light-headed or dizzy.

Normal range: between 60-90 liters/minute

Pressure Limit

The pressure limit setting is designed to prevent the overuse of ventilators and can help nurses track how much they are using. When choosing a pressure limit setting, it’s important to consider factors such as the client’s age and weight.

Normal range: Do not exceed 15–20 cmH2O/L/s

Fraction of Inspired Oxygen (FiO2)

The FiO2 Ventilator Setting is the percentage of oxygen in the air pumped into a client’s lungs.

When you have a client who needs supplemental oxygen, you need to set the FiO2 ventilator setting high enough so that they get enough oxygen (without getting too much). This will keep them from developing hypercapnia, a condition caused by too much carbon dioxide in their bloodstream.

Normal range: 80-100mmHg

Positive End-Expiratory Pressure (PEEP)

The Positive End-Expiratory Pressure (PEEP) ventilator setting is a way to keep clients’ lungs from collapsing when they can’t breathe on their own.

The PEEP setting allows oxygen to be delivered to the bloodstream much easier, so the client can get more oxygen into their body.

Normal range: ~0.5 ratio of the lung to the total elastance

Tidal Volume

The tidal volume ventilator setting is the amount of air that’s delivered to a client during a single breath.

Nursing consideration is also key with the tidal volume setting when administering oxygen, since it affects the amount of oxygen the client receives. If a client needs more oxygen, then their tidal volume needs to be increased to receive an adequate supply of oxygen.

Normal range: 4-6-mL/kg

Alarms

Ventilator alarms are set up to help keep ventilator settings within a safe range and avoid over-ventilation or under-ventilation. The alarms also alert nurses if they need to adjust settings based on how well clients breathe.

The most common alarms and their triggers include:

Low Pressure (Low Tidal Volume Alarm)

• Loss of connection
• Leak
• ET Tube displacement
• Disconnection

High Pressure (High Peak Pressure Alarm)

• High Blockage
• Kinks in the tube
• Excessive airway secretions
• Mucus plug
• Coughing
• Pulmonary edema
• Pneumothorax

Modes

Assist-Control (AC)

• Assist Control Full machine control
• 100% Machine control

Memory Trick: Actively Controls breathing

Synchronized Intermittent Mandatory Ventilation (SIMV)

• “Weaning Mode”
• Client controls breathing mainly, but the machine assists

Memory Trick: SIMV Step down

Monitoring

VE

• Minute Ventilation
• Amt. of air delivered per minute

Memory Trick: Ventilations every minute

Peak Inspiratory Pressure (PIP)

• Max pressure during inspiration

Memory Trick: PIP is the TIP of max pressure

Pplat

• Plateau Pressure
• Indicates Lung compliance
• Pressure is applied to hold open small airways & alveoli before expiration

Memory Trick: Plateau Pause lung

Mechanical Ventilation

Mechanical ventilation refers to a machine mechanically giving breaths or ventilations to a client – like an air pump that pumps air into bicycle tires.

Mechanical ventilation is a way to provide oxygen to the body when it’s not able to get enough oxygen on its own. It’s typically used for clients with respiratory problems or those who have gone into a coma or are otherwise unable to breathe on their own.

Types of Mechanical Ventilation

Mechanical ventilation inflates and deflates an airbag that sits over a client’s chest cavity (where the lungs are). This moves air in and out of the lungs, which helps clients breathe.

The machine uses pressure sensors to detect when it should inflate or deflate the airbag. This is so that it keeps up with the client’s body (if it was breathing on its own), but at a much slower rate than normal.

Mechanical ventilation comes in two forms: positive-pressure and negative-pressure.

Positive-Pressure Ventilation

Positive-pressure mechanical ventilation is a way to deliver oxygen to the client. It uses a higher pressure level to force oxygen into the lungs, rather than to allow them to expand naturally and pull in air.

When clients are put on positive-pressure ventilation, they will be connected to the ventilator via their face or chest.

Negative-Pressure Ventilation

Negative-pressure mechanical ventilation is a type of non-invasive mechanical ventilation that uses a ventilator to apply pressure to the lungs. It’s typically used for clients experiencing pneumonia, asthma, or COPD. One of the reasons it’s so effective is that it prevents air from leaking out of the lungs, which helps keep them inflated and able to do their job properly.

Other Ventilation Mechanisms

Suction

Suction is one of the most critical components of ventilator-assisted respiratory care. Suction is a way of removing excess fluid from the client’s airways and lungs. This helps keep their airway clear so they can breathe more easily.

Suctioning can be done in two ways: with an endotracheal suction catheter (ETSC) or with a tracheostomy tube.

ETSCs help clear mucus from the lungs of clients who can’t cough effectively on their own. On the other hand, tracheostomy tubes allow clients with permanent laryngeal dysfunction or significant edema in their airways to breathe more easily.

Extubation

Extubation means taking someone off of a ventilator, and it’s a very delicate process. You must be careful not to let the client breathe on their own before they’re ready, but you also can’t leave them on the ventilator for too long. If you take them off the ventilator at the wrong time, then their lungs could collapse, and they’ll stop breathing.

Tracheostomy Care

Tracheostomies are a common form of care for clients with acute respiratory failure. They allow the client to breathe through an artificial airway (tracheal tube).

When a client has a tracheostomy and is on a ventilator, you have to consider the pressure support setting. When this is set too high, it can cause the client to cough or gag. Also consider the PEEP setting, which can help prevent atelectasis.

Ventilator Settings Conclusion

To monitor the state of your clients on a ventilator, you must be competent in setting up and selecting the appropriate modes, ventilation, and settings. In actual use, it can be simple to get some ventilator settings wrong. However, it is your responsibility as a nurse to ensure that your client receives the proper ventilator settings.

Sources

https://ecampusontario.pressbooks.pub/mechanicalventilators/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5537121/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6212352/