ISO 19223:2019

Lung ventilators and related equipment — Vocabulary and semantics

Lung ventilators and related equipment — Vocabulary and semantics

General Information

• Status: Published
• Technical Committee: COVID 19 - COVID 19 - ISO
• Directive: standardi COVID-19 - UPDATE ON THE AVAILABILITY OF CEN, CENELEC, ISO, IEC STANDARDS AND THEIR NATIONAL ADOPTIONS IN RESPONSE TO THE COVID-19 OUTBREAK

Standards Content (Sample)

Posebna objava SIST z dovoljenjem CEN, CENELEC, ISO in IEC: Za potrebe zagotavljanja brezplačnega dostopa do vsebin standardov v času epidemije COVID-19.
Samo za branje. Kopiranje in posredovanje prepovedano. © SIST 2020-04-10
INTERNATIONAL ISO
STANDARD 19223
First edition
2019-07
Lung ventilators and related
equipment — Vocabulary and
semantics
Ventilateurs pulmonaires et équipement associé — Vocabulaire et
sémantique
Reference number
ISO 19223:2019(E)
©
ISO 2019

---------------------- Page: 1 ----------------------
Posebna objava SIST z dovoljenjem CEN, CENELEC, ISO in IEC: Za potrebe zagotavljanja brezplačnega dostopa do vsebin standardov v času epidemije COVID-19.
Samo za branje. Kopiranje in posredovanje prepovedano. © SIST 2020-04-10
ISO 19223:2019(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

---------------------- Page: 2 ----------------------
Posebna objava SIST z dovoljenjem CEN, CENELEC, ISO in IEC: Za potrebe zagotavljanja brezplačnega dostopa do vsebin standardov v času epidemije COVID-19.
Samo za branje. Kopiranje in posredovanje prepovedano. © SIST 2020-04-10
ISO 19223:2019(E)

Contents Page
Foreword .iv
Introduction .v
1 * Scope . 1
2 Normative references . 1
3 * Terms, definitions, symbols, and abbreviated terms . 1
3.1 General artificial-ventilation terminology . 2
3.2 Breath terminology . 9
3.3 Lung inflation terminology .13
3.4 * Time, phase and cycle terminology .18
3.5 * Rate terminology .23
3.5.1 Preferred rate concepts.23
3.5.2 Secondary rate concepts — Rate terms for use if required for specific purposes 25
3.6 Pressure terminology .26
3.7 Flow terminology .30
3.8 Volume terminology .34
3.9 Initiation and termination terminology .38
3.10 * Baseline and PEEP terminology .43
3.11 * Mode terminology .48
3.12 * Bi-level terminology .60
3.13 Safety limits and alarm terminology .64
3.14 Gas port terminology .67
Annex A (informative) Rationales and guidance.69
Annex B (informative) Conceptual relationships between ventilator actions and types of breath .75
Annex C (informative) Illustrations of ventilation terms .77
Annex D (informative) Classification of inflation-types .109
Annex E (informative) Classification of ventilation-modes .114
Annex F (informative) Concepts relating to baseline airway pressures and PEEP as used in
this document .116
Annex G (informative) Conventions followed in this document .125
Annex H (informative) Implementation guidance for the vocabulary of this document .127
Annex I (informative) Equivalence declaration tables.129
Annex J (informative) Terminology — Alphabetized index of defined terms .132
Bibliography .139
© ISO 2019 – All rights reserved iii

---------------------- Page: 3 ----------------------
Posebna objava SIST z dovoljenjem CEN, CENELEC, ISO in IEC: Za potrebe zagotavljanja brezplačnega dostopa do vsebin standardov v času epidemije COVID-19.
Samo za branje. Kopiranje in posredovanje prepovedano. © SIST 2020-04-10
ISO 19223:2019(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso
.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 121, Anaesthetic and respiratory
equipment, Subcommittee SC 4, Vocabulary and semantics.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2019 – All rights reserved

---------------------- Page: 4 ----------------------
Posebna objava SIST z dovoljenjem CEN, CENELEC, ISO in IEC: Za potrebe zagotavljanja brezplačnega dostopa do vsebin standardov v času epidemije COVID-19.
Samo za branje. Kopiranje in posredovanje prepovedano. © SIST 2020-04-10
ISO 19223:2019(E)

Introduction
The characteristics of ventilation-modes of current automatic lung ventilators are often not well
understood. The current terminology used for their description is based on that introduced in the early
days of mechanical ventilation, but with the advances in ventilators, and ventilation-modes that have
evolved over recent years, the language used has been continuously adapted. In the absence of any
effective international coordinating action, this has inevitably led to increasing inconsistencies in the
way in which well-established terms and their derivatives are used.
To further compound the difficulties in understanding these complexities, some ventilator manufacturers
have created new proprietary terms to describe these alternative ways of ventilating patients, and
others have used existing terms with different meanings in different situations. This has led to patient
safety hazards, an example being that lung ventilator clinical orders (settings) for one model of ventilator
can be quite different from those required to get the same result from a different ventilator.
Recognizing these difficulties, ISO Technical Committee ISO/TC 121 requested its Subcommittee, SC 4,
to completely review the terminology and semantics for patient ventilation with a view to compiling a
standardized vocabulary that is applicable to current and, as far as possible, future practice. The primary
objective was to use as much existing terminology as possible, while clarifying its meaning and limiting
its potential for misuse by defining it more precisely. New terms were only introduced where there was
no alternative, either in order to name new concepts or where the misuse of existing vocabulary has
become so widespread that the term has become meaningless or unacceptably ambiguous. Importance
was placed on a vocabulary that would communicate a clear mental model of how the selected settings
would determine the interaction between the patient and the ventilator.
In order to achieve a vocabulary that is coherent, consistent and applicable to a range of fields such as
patient care, research, data collection and incident reporting, this document has been developed with the
participation, cooperation and assistance of members of other standards development organizations,
and of major international ventilator manufacturers. The applications include lung ventilators, medical
data systems facilitating clinical care and research, interoperability, incident reporting and equipment
maintenance.
The early work by the subcommittee in establishing how a standardized vocabulary should be
structured increasingly led to the conclusion that it would be necessary to revert to first principles.
It was recognized that much of the current terminology has its origins in the early use of automatic
ventilation, when the emphasis was inevitably on how best to save the lives of patients who could not
breathe for themselves and, consequently, only made basic provisions for the patient's own respiratory
activity. Since that time, ventilators have become increasingly interactive with the patient, such that it is
now necessary to consider their use from a ventilator-patient system perspective because it is no longer
possible, with any certainty, to predict ahead of time how that interaction will take place.
The terminology in this document is defined and used in a way that makes it capable of facilitating,
unambiguously, both the setting of a ventilator and how to describe and record the resultant ventilator-
patient interactions, continuously and at defined points within the course of ventilation. This includes
the result of the complex interactions that occur when additional breaths are taken during an assured-
inflation cycle, as can occur, for example, during APRV (airway pressure release ventilation).
This document seeks both to provide a consensus view and the basis for a coherent language for
describing ventilator function. Now that the fundamental concepts of artificial ventilation practice
within the scope of this document have matured, it has been possible to review the boundaries between
the various concepts of established ventilation-modes and the methods of artificially inflating a patient's
lungs and to formulate definitions that clarify the common elements and the distinctions. In particular,
the scopes of several concepts that were appropriate to earlier technology and practice have become
inadequate to encompass new developments and it was found necessary to subdivide them. Some of
their designating terms have, therefore, had to be deprecated, replaced or constrained using more
restrictive definitions, resulting in an inevitable reintroduction of some little-used legacy terms and
the need to create a few new terms.
© ISO 2019 – All rights reserved v

---------------------- Page: 5 ----------------------
Posebna objava SIST z dovoljenjem CEN, CENELEC, ISO in IEC: Za potrebe zagotavljanja brezplačnega dostopa do vsebin standardov v času epidemije COVID-19.
Samo za branje. Kopiranje in posredovanje prepovedano. © SIST 2020-04-10
ISO 19223:2019(E)

The overall objective is to encourage a more disciplined use of ventilator vocabulary so that operators
trained in the application of this document will be able to move easily from one ventilator to another
and operate each one, with confidence, after a minimum amount of training. Although it is recognized
that change will not be immediate, it is expected that this discipline will feed through into scientific
publications, textbooks and training so that, over time, a standardized basic language of artificial
ventilation will become internationally established.
Examples of the application of this document are illustrated in the figures of Annexes C and F but these
are not intended to indicate a requirement, nor to impose any restriction on the design of artificial
ventilation devices.
Included with many of the terms are notes to entry that provide supplementary information, including
explanations of the semantics of the term along with their classification schemes. This format is not
only a requirement of ISO 704 but, unlike with such information in an annex, ensures that it remains
associated with the term when viewed on the free-to-access ISO Online Browsing Platform.
Some of the terms in this document are principally intended for technical documents, informatics and
related applications, and might have little applicability to ventilator labelling and instructions for use.
In this document, the following print types are used:
Definitions: roman type.
Material appearing outside of tables, such as notes, examples and references: smaller type.
Terms defined in Clause 3 of this document or as noted, apart from those in the form of acronyms or
initialisms or when used in headings or tables: italic type.
In this document, the conjunctive “or” is used as an “inclusive or” so a statement is true if any
combination of the conditions is true.
The verbal forms used in this document conform to the usage described in ISO/IEC Directives, Part 2,
Annex H. For the purposes of this document, the auxiliary verb
— “shall” means that compliance with a requirement or a test is mandatory for compliance with this
document,
— “should” means that compliance with a requirement or a test is recommended but is not mandatory
for compliance with this document, and
— “may” is used to describe a permissible way to achieve compliance with a requirement or test.
An asterisk (*) as the first character of a title or at the beginning of a paragraph or table title indicates
that there is guidance or rationale related to that item in Annex A.
Colour coding is employed in most of the figures in Annexes B, C and F of this document to help
distinguish between some of the specific characteristics being illustrated. The coding used for each
figure, or set of figures, is provided either in its own specific key or in the introductory text of each
annex, as applicable.
NOTE The following figures and tables have been reproduced from Reference [34] with permission:
— Figures: B.1, C.1 to C.35 and F.1 to F.7;
— Tables: D.1 to D.3, E.1 and E.2.
vi © ISO 2019 – All rights reserved

---------------------- Page: 6 ----------------------
Posebna objava SIST z dovoljenjem CEN, CENELEC, ISO in IEC: Za potrebe zagotavljanja brezplačnega dostopa do vsebin standardov v času epidemije COVID-19.
Samo za branje. Kopiranje in posredovanje prepovedano. © SIST 2020-04-10
INTERNATIONAL STANDARD ISO 19223:2019(E)
Lung ventilators and related equipment — Vocabulary and
semantics
1 * Scope
This document establishes a vocabulary of terms and semantics for all fields of respiratory care
involving mechanical ventilation, such as intensive-care ventilation, anaesthesia ventilation, emergency
and transport ventilation and home-care ventilation, including sleep-apnoea breathing-therapy
equipment. It is applicable
— in lung ventilator and breathing-therapy device standards,
— in health informatics standards,
— for labelling on medical electrical equipment and medical electrical systems,
— in medical electrical equipment and medical electrical system instructions for use and accompanying
documents,
— for medical electrical equipment and medical electrical systems interoperability, and
— in electronic health records.
This document is also applicable to those accessories intended by their manufacturer to be connected to
a ventilator breathing system or to a ventilator, where the characteristics of those accessories can affect
the basic safety or essential performance of the ventilator and ventilator breathing system.
NOTE This document can also be used for other applications relating to lung ventilation, including non-
electrical devices and equipment, research, description of critical events, forensic analysis and adverse event
(vigilance) reporting systems.
This document does not specify terms specific to breathing-therapy equipment, or to physiologic closed-
loop ventilation, high-frequency ventilation or negative-pressure ventilation; nor to respiratory support
using liquid ventilation or extra-corporeal gas exchange, or oxygen, except where it has been considered
necessary to establish boundaries between bordering concepts.
2 Normative references
There are no normative references in this document.
3 * Terms, definitions, symbols, and abbreviated terms
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
NOTE For convenience, an index and a list of sources of all defined terms used in this document are provided
in Annex J.
© ISO 2019 – All rights reserved 1

---------------------- Page: 7 ----------------------
Posebna objava SIST z dovoljenjem CEN, CENELEC, ISO in IEC: Za potrebe zagotavljanja brezplačnega dostopa do vsebin standardov v času epidemije COVID-19.
Samo za branje. Kopiranje in posredovanje prepovedano. © SIST 2020-04-10
ISO 19223:2019(E)

3.1 General artificial-ventilation terminology
3.1.1
ventilator
lung ventilator
DEPRECATED: respirator
medical device or medical electrical equipment intended to provide artificial ventilation
Note 1 to entry: In cases of possible ambiguity the full term, lung ventilator, should be used.
Note 2 to entry: See also ventilation (3.1.9).
[SOURCE: ISO 80601-2-12:2011, 201.3.222, modified — Definition split into two terms (see 3.1.1 and
3.1.10).]
3.1.2
airway
connected, gas-containing cavities and passages within the respiratory system, that conduct gas
between the alveoli and the oral and nasal orifices on the surface of the face, or the patient-connection
port if an airway device is used
Note 1 to entry: This is a well-established term that is commonly used in isolation in references to the airway of a
patient. Depending on the context, it is sometimes more helpful to use the qualified term, patient's airway.
Note 2 to entry: See also airway device (3.1.3).
3.1.3
airway device
device intended for use as an interface between the patient-connection port of a ventilator and the
patient's airway, and which has no auxiliary features on which the ventilator is dependent for its normal
operation
EXAMPLE Endotracheal tube; tracheotomy tube; face mask; supralaryngeal airway.
Note 1 to entry: The connection to the patient's airway can be at the face (non-invasive) or internal to the patient
(invasive).
Note 2 to entry: A face mask that intentionally vents respiratory gas to atmosphere by means of a bleed orifice
is a functional part of the ventilator breathing system and therefore not an airway device. With that arrangement,
the face seal of the mask becomes the patient-connection port and there is no patient-connection port connector,
nor an airway device.
Note 3 to entry: See also patient-connection port (3.14.5), airway (3.1.2) and ventilator breathing system (3.1.18).
3.1.4
airway resistance
drop in pressure between the patient-connection port and the alveoli per unit rate of airway flow
Note 1 to entry: The airway resistance is normally expressed as a single coefficient, with the implicit assumptions
that it is independent of the flow rate and of the direction of flow. In practice, these assumptions are typically
only approximately valid.
Note 2 to entry: See also airway (3.1.2).
3.1.5
respiratory system compliance
respiratory compliance
DEPRECATED: lung compliance
elastic characteristic of the lung expressed as the change in lung volume per unit change of airway
pressure in the absence of respiratory activity
Note 1 to entry: In addition to its direct reference, this term or its symbol, C , is used, in context or by qualification,
rs
to designate this concept as a measured quantity (3.1.20).
2 © ISO 2019 – All rights reserved

---------------------- Page: 8 ----------------------
Posebna objava SIST z dovoljenjem CEN, CENELEC, ISO in IEC: Za potrebe zagotavljanja brezplačnega dostopa do vsebin standardov v času epidemije COVID-19.
Samo za branje. Kopiranje in posredovanje prepovedano. © SIST 2020-04-10
ISO 19223:2019(E)

Note 2 to entry: The respiratory system compliance is normally expressed as a single coefficient, with the implicit
assumptions that it is independent of the volume of gas in the lung and of any hysteresis between increasing and
decreasing volumes. In practice, these assumptions are typically only approximately valid.
Note 3 to entry: Respiratory system compliance is typically determined by a static measurement once the airway
pressure has stabilized during an inspiratory pause. In mechanically ventilated patients it is typically determined
as either a static compliance or a dynamic compliance. There might be differences between the values obtained by
these different methods, not only due to the method itself but also due to viscoelastic effects, pressure balancing
throughout the slower compartments of the lungs and possible recruitment effects.
Note 4 to entry: It is sometimes more applicable to express this characteristic as lung elastance, which is simply
the inverse of respiratory system compliance.
Note 5 to entry: See also lung (3.1.16), airway pressure (3.6.1), respiratory activity (3.2.6), respiratory system
(3.1.17), inspiratory pause (3.4.12), pulmonary compliance (3.1.6), static compliance (3.1.7) and dynamic compliance
(3.1.8).
3.1.6
pulmonary compliance
elastic characteristic of the lungs expressed as the change in the lung volume per unit change of the
difference between the alveolar pressure and the pressure in the pleural space
Note 1 to entry: In addition to its direct reference, this term or its symbol, C , is used, in context or by qualification,
L
to designate this concept as a measured quantity (3.1.20). The specific symbol, C , has been adopted because of
L
its established usage in the scientific community to represent the ‘compliance of the lungs’.
Note 2 to entry: The pulmonary compliance is the compliance coefficient relating specifically to the lungs, as
distinct from the respiratory system compliance coefficient, which relates to the whole of the respiratory system
and, therefore, includes the compliance of the thoracic cage. For most patients it is not clinically necessary to
differentiate between the compliance of the lungs alone, and the compliance of the respiratory system, so the more
directly measurable respiratory system compliance provides sufficient information. If an impaired respiratory
system is indicated, the difference might be significant and can justify the more invasive and skilled procedure
required to obtain a measurement of pressure in the pleural space (the intrapleural pressure) and, thereby, that
of the pulmonary compliance.
Note 3 to entry: The difference between the alveolar pressure and the pleural pressure is typically referred to as
the transpulmonary pressure.
Note 4 to entry: The pulmonary compliance is normally expressed as a single coefficient, with the implicit
assumptions that it is independent of the volume of gas in the lungs, of any hysteresis between increasing and
decreasing volumes and of any variation of the pleural pressure within the pleural space. In practice, these
assumptions are typically only approximately valid.
Note 5 to entry: See also lung (3.1.16), airway pressure (3.6.1), respiratory system (3.1.17) and respiratory system
compliance (3.1.5).
3.1.7
static compliance
respiratory system compliance determined, under quasi-static conditions and while connected to a
ventilator, as the measured change in inspiratory volume per unit change in the measured plateau
inspiratory pressure relative to the measured total PEEP
Note 1 to entry: In addition to its direct reference, this term or its symbol, C , is used, in context or by
stat
qualification, to designate this concept as a measured quantity (3.1.20).
Note 2 to entry: For the purposes of this measurement, quasi-static conditions are considered to occur during a
respiratory phase of low airway flow and no significant respiratory activity.
Note 3 to entry: Expressed as an equation: static compliance = inspiratory volume / (plateau pressure – total PEEP).
If the presence of auto-PEEP is not suspected or a value for total PEEP is not readily available, the set BAP may be
used as a substitute for total PEEP in this equation.
Note 4 to entry: See also respiratory system compliance (3.1.5), inspiratory volume (3.8.3), plateau inspiratory
pressure (3.6.4), total PEEP (3.10.6), auto-PEEP (3.10.7) and BAP (3.10.2).
© ISO 2019 – All rights reserved 3

---------------------- Page: 9 ----------------------
Posebna objava SIST z dovoljenjem CEN, CENELEC, ISO in IEC: Za potrebe zagotavljanja brezplačnega dostopa do vsebin standardov v času epidemije COVID-19.
Samo za branje. Kopiranje in posredovanje prepovedano. © SIST 2020-04-10
ISO 19223:2019(E)

3.1.8
dynamic compliance
respiratory system compliance determined during normal mechanical ventilation
Note 1 to entry: In addition to its direct reference, this term or its symbol, C , is used, in context or by
dyn
qualification, to designate this concept as a measured quantity (3.1.20).
Note 2 to entry: Dynamic compliance is a dynamically calculated value obtained during normal mechanical
ventilation by me
...