Types of Ventilation

Various types of ventilation in modern intensive care and emergency medicine are used to support gas exchange in the lungs when the body is no longer able to do so. 

Depending on the clinical picture and the selected ventilator, particular ventilation modes are available with WEINMANN.

What types of ventilation are there?

Ventilation can be divided into invasive and non-invasive ventilation types. Mechanical ventilation can also be controlled, assisted or spontaneous.

If the patient’s spontaneous breathing is not sufficient, the ventilator can support breathing efforts or take over the work of breathing completely:

• With controlled ventilation types, the device takes over the work of breathing completely.
• With assisted ventilation types, the device partially takes over the work of breathing.
• With spontaneous ventilation types, the patient breathes almost independently.[1]

Non-invasive ventilation types

In non-invasive ventilation (NIV), respiratory support is provided without invasive airway access via a full-face mask. Non-invasive forms of ventilation are indicated if oxygenation or ventilation disorders are present and the ventilated person has sufficient spontaneous breathing. 

Invasive ventilation types

The invasive ventilation is performed via an endotracheal tube or a tracheal cannula. This involves creating direct access to the trachea by means of intubation or a tracheotomy. Invasive forms of ventilation are used in particular in the absence of spontaneous breathing or after unsuccessful NIV therapy. 

Simple explanation of ventilation modes

In mechanical ventilation, different forms of ventilation are available, which are referred to as ventilation modes. 

The ventilation mode selected depends on clinical standards, the treatment context and the patient’s condition. In any case, close monitoring of SpO₂, etCO₂ and, in the best case, blood gases is required to check the effectiveness of the selected ventilation mode.

What is the difference between ventilation type and ventilation mode?

The terms ventilation type and ventilation mode are sometimes used synonymously in everyday clinical practice, but strictly speaking they refer to different aspects of mechanical ventilation:

The ventilation type describes how the patient’s ventilation is controlled, e.g. pressure-controlled or volume-controlled or invasive or non-invasive. 

The ventilation mode, on the other hand, refers to the specific technical implementation used for ventilation. It provides information on how the ventilation parameters work and how to set them.

WEINMANN ventilation types

WEINMANN covers the following types of ventilation:

• Volume-controlled ventilation
• Pressure-controlled ventilation
• Hybrid ventilation modes
• Spontaneous ventilation modes
• Special ventilation functions

The available ventilation modes include both standard ventilation types, such as IPPV or non-invasive CPAP therapy, and ventilation modes exclusive to WEINMANN, such as CCSV. 

A series of special ventilation functions uses preconfigured settings to facilitate work in emergency situations. RSI and CPR modes are examples of this, as are the emergency modes for infants, adults, and children.

Volume-controlled ventilation modes

IPPV, S-IPPV, SIMV, SIMV + ASB

In the context of volume-controlled ventilation (VCV), the patient is administered a previously specified minute volume up to a maximum ventilation pressure limit (pMax).

Tidal volume, respiratory rate, maximum ventilation pressure (pMax), and positive end-expiratory pressure (PEEP) can be set. Volume is supplied to the lungs as a function of these parameters until peak pressure (pPeak) is reached. 

In the subsequent plateau phase, pressure drops slightly until the end of the inspiration phase. Tidal volume remains constant, even in instances where respiratory system compliance changes quickly.

Indications for volume-controlled ventilation include neurological, muscular or lung diseases in which the respiratory musculature becomes weak, with the result that external support is required.

The methods of volume-controlled ventilation include the following modes:

• Intermittent Positive Pressure Ventilation (IPPV),
• Synchronized Intermittent Positive Pressure Ventilation (S-IPPV), and
• Synchronized Intermittent Mandatory Ventilation (SIMV).

With S-IPPV and SIMV, the work of breathing is performed partly by the ventilator and partly by the patient.

 MORE on volume-controlled ventilation

Pressure-controlled ventilation modes

PCV, aPCV, BiLevel, BiLevel + ASB, CCSV

The pressure-controlled ventilation (PCV) specifies the pressure level to be reached during inspiration and expiration. Ventilation pressure (pInsp), respiratory rate, maximum ventilation pressure (pMax), and positive end-expiratory pressure (PEEP) can be set by the user. 

In pressure-controlled ventilation, the tidal volume administered results from the patient’s resistance (airway resistance) and compliance (degree to which the lung can expand). 

In the event of increased resistance and/or reduced compliance, it is possible for reduced volume to be administered whilst pressure remains the same, for example (this is compared to a situation with normal values for resistance and compliance). The starting point of the ventilation cycle is a fixed pressure level – the positive end-expiratory pressure (PEEP): PEEP is maintained throughout expiration and keeps the airways open. 

In the case of inspiration, the patient is supplied with respiratory gas until a specified inspiratory pressure (pInsp) has been reached. This pressure is maintained for the duration of inspiration. On expiration, the pressure level is reduced back to PEEP level and the ventilation cycle begins again.

The decelerating inspiratory flow in this process ensures better oxygenation and lower airway pressures.

Pressure-controlled ventilation is indicated in the case of neurological or muscular diseases which weaken the respiratory musculature and in the case of lung diseases such as acute respiratory distress syndrome (ARDS).

Particular types of pressure-controlled ventilation are Assisted Pressure Controlled Ventilation (aPCV), BIPAP and Chest Compression Synchronized Ventilation (CCSV), which was specially developed for resuscitation.

MORE on pressure-controlled ventilation

Hybrid ventilation modes

PRVC, PRVC + ASB

The hybrid type of ventilation Pressure-Regulated Volume-Controlled Ventilation (PRVC) was developed to benefit from the advantages of both volume-controlled and pressure-controlled ventilation.

This combines volume-controlled ventilation with the decelerating flow of pressure-controlled ventilation. The target tidal volume, respiratory rate, maximum ventilation pressure (pMax) and positive end-expiratory pressure (PEEP) can be set by the user.

Within a test breath, the ventilator is used to select inspiratory pressure such that the target tidal volume is achieved by pressure-controlled breaths.

The pressure level is constantly adapted “breath-by-breath” and set to the lowest level. PRVC can be used in combination with Assisted Spontaneous Breathing (ASB) to support inadequate spontaneous breathing with pressure.

Spontaneous ventilation modes

CPAP, CPAP + ASB

Spontaneous ventilation modes such as Continuous Positive Airway Pressure (CPAP) are frequently used by emergency medical services in the context of non-invasive ventilation. 

In CPAP, breathing is not controlled, but effected independently via a ventilation mask. The ventilator simply supports spontaneous breathing. 

The set PEEP level is always reached at the end of every ventilation cycle. CPAP is usually used in the case of oxygenation and ventilation disorders.

A distinction is made here between the following modes:

1. CPAP: In pure CPAP, a positive inspiratory flow is delivered continuously, regardless of the patient’s spontaneous breathing. The patient can breathe independently at the set CPAP pressure level.
2. CPAP + ASB: CPAP in combination with Assisted Spontaneous Breathing (ASB) detects the patient’s efforts to breathe in, and synchronizes delivery of pressure support with them, making it easier for the patient to breathe.

In both modes, it is possible to add mechanical apnea ventilation which is initiated whenever the affected patient does not breathe spontaneously. 

You can find a clear infographic on modes of mechanical ventilation here.
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Special ventilation functions

CPR, RSI, Manual

WEINMANN has developed special ventilation functions to support the workflow in particular emergency situations. These functions are used particularly in emergency situations such as cardiopulmonary resuscitation or anesthesia induction.

Manual mode is used mainly in cardiopulmonary resuscitation (CPR) and in anesthesia induction (Rapid Sequence Induction, RSI). The ventilation type allows the emergency medical services to supply the patient with mechanical breaths on an individual basis as required. 

The mechanical breaths in WEINMANN ventilators are initiated by a button (MEDUtrigger) instead of a bag-valve mask. This special function can thus replace bag mask ventilation.

MORE about special ventilation functions

Ventilation types & modes: an overview

WEINMANN offers a variety of ventilation modes for emergency care. All mechanical WEINMANN ventilation types for emergency medical services can be found in the overview. 

^[1] R. Larsen, T. Ziegenfuss (2017). Pocket Guide Beatmung [Pocket Guide to Ventilation]. Berlin Heidelberg: Springer-Verlag, p. 18f.

^[2] Larsen R. Maschinelle Beatmung und NIV [Mechanical ventilation and NIV]. Anesthesia und Intensivmedizin für die Fachpflege [Anesthesia and intensive care for specialist medical care]. 2016 Jun 14:745–95. German. doi: 10.1007/978-3-662-50444-4_56. PMCID: PMC7531439; see objectives of ventilation: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7531439/