ISO 81060-2:2009
(Main)Non-invasive sphygmomanometers - Part 2: Clinical validation of automated measurement type
Non-invasive sphygmomanometers - Part 2: Clinical validation of automated measurement type
ISO 81060-2:2009 is applicable to all sphygmomanometers that sense or display pulsations, flow or sounds for the estimation, display or recording of blood pressure. These sphygmomanometers need not have automatic cuff inflation. ISO 81060-2:2009 covers sphygmomanometers intended for use in all patient populations (e.g. all age and weight ranges), and all conditions of use (e.g. ambulatory blood pressure monitoring, stress testing blood pressure monitoring and blood pressure monitors for the home healthcare environment or self-measurement). ISO 81060-2:2009 specifies additional disclosure requirements for the accompanying documents of sphygmomanometers validated according to this International Standard.
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Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 81060-2
First edition
2009-05-01
Non-invasive sphygmomanometers —
Part 2:
Clinical validation of automated
measurement type
Sphygmomanomètres non invasifs —
Partie 2: Validation clinique pour type à mesurage automatique
Reference number
ISO 81060-2:2009(E)
©
ISO 2009
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ISO 81060-2:2009(E)
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ISO 81060-2:2009(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 General requirements for validation studies .2
4.1 Validation methods. 2
4.2 Ethical requirements . 2
5 Validation with auscultatory reference sphygmomanometer . 2
5.1 Subject requirements . 2
5.2 Validation method with reference sphygmomanometer. 4
6 Validation with reference invasive blood pressure monitoring equipment. 14
6.1 Patient requirements . 14
6.2 Validation methods with reference invasive blood pressure monitoring equipment . 16
7 * Pregnant, including pre-eclamptic, patient populations. 19
Annex A (informative) Rationale . 20
Annex B (normative) Target heart rates for exercise stress testing. 29
Annex C (informative) Reference to the essential principles . 30
Annex D (informative) Terminology — Alphabetized index of defined terms. 32
Bibliography . 33
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ISO 81060-2:2009(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 81060-2 was prepared by Technical Committee ISO/TC 121, Anaesthetic and respiratory equipment,
Subcommittee SC 3, Lung ventilators and related equipment and Technical Committee IEC/TC 62, Electrical
Equipment in Medical Practice, Subcommittee 62D, Electromedical Equipment.
ISO 81060 consists of the following parts, under the general title Non-invasive sphygmomanometers:
⎯ Part 1: Requirements and test methods for non-automated measurement type
⎯ Part 2: Clinical validation of automated measurement type
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ISO 81060-2:2009(E)
Introduction
Determination of blood pressure is an important procedure that is clinically used to assess the health of the
patient.
Frequent determination of blood pressure is routine during anaesthesia. Blood pressure serves to aid in
drug titration and fluid management and to provide warning of conditions that could affect patient morbidity
and mortality.
In this document, the following print types are used:
⎯ requirements, compliance with which can be verified, and definitions: roman type;
⎯ notes and examples: smaller roman type;
⎯ terms defined in this document: bold type.
Throughout this document, text for which a rationale is provided in Annex A is indicated by an asterisk (*).
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INTERNATIONAL STANDARD ISO 81060-2:2009(E)
Non-invasive sphygmomanometers —
Part 2:
Clinical validation of automated measurement type
1 Scope
This part of ISO 81060 specifies the requirements and methods for the clinical validation of me equipment
used for the intermittent non-invasive automatic estimation of the arterial blood pressure by utilizing a cuff.
This part of ISO 81060 is applicable to all sphygmomanometers that sense or display pulsations, flow or
sounds for the estimation, display or recording of blood pressure. These sphygmomanometers need not
have automatic cuff inflation. This part of ISO 81060 covers sphygmomanometers intended for use in all
patient populations (e.g. all age and weight ranges), and all conditions of use (e.g. ambulatory blood
pressure monitoring, stress testing blood pressure monitoring and blood pressure monitors for the home
healthcare environment or self-measurement).
EXAMPLE Automated sphygmomanometer as given in IEC 80601-2-30 validated by this part of ISO 81060.
This part of ISO 81060 specifies additional disclosure requirements for the accompanying documents of
sphygmomanometers validated according to this part of ISO 81060.
This part of ISO 81060 is not applicable to the validation of non-automated sphygmomanometers as given
in ISO 81060-1 or invasive blood pressure monitoring equipment as given in IEC 60601-2-34.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
1)
ISO 14155:— , Clinical investigation of medical devices for human subjects — Good clinical practice
ISO 81060-1:2007, Non-invasive sphygmomanometers — Part 1: Requirements and test methods for non-
automated measurement type
IEC 80601-2-30:2009, Medical electrical equipment — Part 2-30: Particular requirements for basic safety and
essential performance of automated non-invasive sphygmomanometers
IEC 60601-1:2005, Medical electrical equipment — Part 1: General requirements for basic safety and
essential performance
IEC 60601-1-11, Medical electrical equipment — Part 1-11: General requirements for basic safety and
essential performance — Collateral standard: Requirements for medical electrical equipment and medical
electrical systems used in home care applications
IEC 60601-2-34:2000, Medical electrical equipment — Part 2-34: Particular requirements for the safety,
including essential performance, of invasive blood pressure monitoring equipment
1) To be published.
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ISO 81060-2:2009(E)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 14155, IEC 80601-2-30,
IEC 60601-1, IEC 60601-1-11, IEC 60601-2-34 and the following apply. For convenience, an alphabetized list
of the sources of all defined terms used in this document is given in Annex D.
3.1
reference
established accuracy used for clinical evaluation of other instruments
3.2
sphygmomanometer
me equipment for non-invasive estimation of systemic arterial blood pressure
3.3
sphygmomanometer-under-test
sphygmomanometer being clinically evaluated
4 General requirements for validation studies
4.1 Validation methods
Sphygmomanometers other than non-automated sphygmomanometers shall be clinically validated either
by using a non-invasive (auscultatory) reference sphygmomanometer or by using reference invasive
blood pressure monitoring equipment according to this part of ISO 81060 in each mode of operation.
EXAMPLE 1 Adult and neonatal mode.
EXAMPLE 2 Slow and fast cuff deflation rate mode.
A clinical validation study shall be considered a type test.
Consider compliance with the requirements of this subclause to exist when the criteria of the relevant
inspections and tests in this part of ISO 81060 are met.
4.2 Ethical requirements
All clinical validation studies shall comply with the requirements of ISO 14155. Validation with reference
invasive blood pressure monitoring equipment should not be used for patients or subjects solely for the
purpose of validating sphygmomanometer performance.
NOTE Some authorities with jurisdiction have additional requirements.
Check compliance by application of the requirements of ISO 14155.
5 Validation with auscultatory reference sphygmomanometer
5.1 Subject requirements
5.1.1 * Number
An auscultatory reference sphygmomanometer validation study shall consist of a minimum of 85 subjects. If
not otherwise specified, at least three valid blood pressure determinations shall be taken for each subject.
There shall be a minimum of 255 valid paired blood pressure determinations.
Check compliance by inspection of the clinical investigation report.
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ISO 81060-2:2009(E)
5.1.2 * Gender distribution
At least 30 % of the subjects shall be male and at least 30 % of the subjects shall be female.
Check compliance by inspection of the clinical investigation report.
5.1.3 * Age distribution
For a sphygmomanometer intended for use on adults and/or adolescent patients, the ages of the subjects
included in the validation study shall be > 12 y.
NOTE 1 Minimum total of 85 subjects.
For a sphygmomanometer additionally intended for use in children, 35 child subjects aged between 3 y and
12 y shall be included in the validation study.
NOTE 2 Minimum total of 85 subjects.
If the sphygmomanometer has a special mode for children, in that mode, children shall be considered a
special patient population (see 5.1.6). In that mode, children are exempt from the blood pressure distribution
requirements of 5.1.5.
Children < 3 y shall not be included in an auscultatory reference sphygmomanometer validation study.
Check compliance by inspection of the accompanying document and the clinical investigation report.
5.1.4 * Limb size distribution
For a sphygmomanometer intended for use with a single cuff size, at least 40 % of the subjects shall have a
limb circumference which lies within the upper half of the specified range of use of the cuff and at least 40 %
shall have a limb circumference within the lower half. At least 20 % of the subjects should have a limb
circumference which lies within the upper quarter of the specified range of use of the cuff and at least 20 %
should have a limb circumference within the lower quarter.
For a sphygmomanometer intended for use with multiple cuff sizes, each cuff size shall be tested on at
least 1/(2 × n) of the subjects, where n is the number of cuff sizes.
Check compliance by inspection of the accompanying document and the clinical investigation report.
5.1.5 * Blood pressure distribution
At least 5 % of the readings shall have a systolic blood pressure u 100 mmHg.
At least 5 % of the readings shall have a systolic blood pressure W 160 mmHg.
At least 20 % of the readings shall have a systolic blood pressure W 140 mmHg.
At least 5 % of the readings shall have a diastolic blood pressure u 60 mmHg.
At least 5 % of the readings shall have a diastolic blood pressure W 100 mmHg.
At least 20 % of the readings shall have a diastolic blood pressure W 85 mmHg.
Check compliance by inspection of the clinical investigation report.
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ISO 81060-2:2009(E)
5.1.6 * Special patient populations
A sphygmomanometer that is intended for use in special patient populations where there is objective
evidence that the accuracy of the sphygmomanometer might be problematic in those patient populations,
shall be clinically evaluated in those patient populations. See also Clause 7.
EXAMPLES Use with patients who have atrial fibrillation (AF), premature ventricular beats and peripheral arterial
disease (PAD).
If the sphygmomanometer has been evaluated according to the requirements of 5.1.1, it shall then be
validated in at least an additional 35 special population subjects. Otherwise, the evaluation in accordance with
the requirements of 5.1.1 shall only consist of subjects from the special population.
The special population shall be defined in clear terms and address the following attributes: gender (see 5.1.2),
age (see 5.1.3), limb size (see 5.1.4) and blood pressure (see 5.1.5). A summary of this information shall be
disclosed in the instructions for use.
Check compliance by inspection of the instructions for use and the clinical investigation report.
5.2 Validation method with reference sphygmomanometer
5.2.1 * Subject preparation
See Reference [32].
Unless otherwise indicated by the instructions for use of the sphygmomanometer-under-test, position the
subject such that the subject:
⎯ is comfortable;
EXAMPLE Comfortably seated with legs uncrossed and feet flat on the floor.
⎯ has the back, elbow and forearm supported;
⎯ has the middle of cuff at the level of the right atrium of the heart.
Recommend that the subject be as relaxed as possible and that they avoid talking during the entire procedure.
Before the first reading is taken, 5 min should elapse.
5.2.2 * Observer preparation
Observers should be trained in using a proper methodology for performing a resting blood pressure
determination by utilizing an accepted clinical protocol for blood pressure measurement. See References [8],
[28], [29], [32] and [45]. They should have sufficient practice in performing blood pressure determinations.
Each observer's recording of observations of the reference sphygmomanometer shall not be visible to the
other observer. The readings of the sphygmomanometer-under-test shall not be visible to either of these
observers.
EXAMPLE 1 Utilizing a third observer for recording the readings of the sphygmomanometer-under-test.
EXAMPLE 2 Utilizing an electronic means for recording the readings of the sphygmomanometer-under-test.
Instruct the observers to determine diastolic blood pressure as the last audible Korotkoff sound (fifth phase
or K5), except in children between 3 y and 12 y, pregnant subjects, and subjects during exercise, where the
fourth phase (K4) is used.
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ISO 81060-2:2009(E)
Instruct the observers to use K4 for the determination of diastolic blood pressure when sounds are audible
with the cuff deflated.
Instruct the observers to record which Korotkoff sound has been used for the determination of diastolic blood
pressure.
The Korotkoff sound used for determination of diastolic blood pressure in the clinical validation study shall
be disclosed in the instructions for use of a sphygmomanometer.
EXAMPLE K5 was used on 65 subjects and K4 was used on 20 subjects.
5.2.3 * Reference determination
Two observers shall make simultaneous blood pressure determinations on each subject using a double
stethoscope.
Unless the sphygmomanometer-under-test is intended for use during significantly irregular heart rhythm
and if either observer detects significantly irregular heart rhythm, that determination shall be excluded.
EXAMPLES Bigeminy, trigeminy, isolated VPB, atrial fibrillation.
NOTE 1 Although evaluation of blood pressure in patients with atrial fibrillation is clinically important, there are
currently no generally-accepted guidelines for determining the blood pressure in such individuals.
Any pair of observers' determinations with a difference greater than 4 mmHg shall be excluded. The
observers' individual values of each determination shall be averaged to create the reference blood pressure
determination.
The observer-to-observer differences shall be reviewed after completing a set of pairs of test-reference
determinations. If any determinations are excluded, additional pair(s) of determinations shall be taken to
ensure that the needed number of valid test-reference pairs are available. A maximum of eight pairs of
determinations should be taken.
Use a reference sphygmomanometer that complies with the requirements of ISO 81060-1, except that the
maximum permissible error shall be ± 1 mmHg. Reading of the values on the reference
sphygmomanometer should be as accurate as possible. When reading the value on the reference
sphygmomanometer, the observers should avoid parallax errors. Rounding has a negative effect on the
results of the clinical validation.
NOTE 2 The cuff is considered part of the reference sphygmomanometer. A cuff that does not comply with
ISO 81060-1 cannot be used.
5.2.4 Validation methods
5.2.4.1 Same arm simultaneous method
5.2.4.1.1 * Procedure
This method shall only be used with a sphygmomanometer-under-test:
⎯ that is designed for use on the upper arm;
⎯ where:
⎯ the continuous linear deflation rate is 2 mmHg/s to 3 mmHg/s or
⎯ for a sphygmomanometer-under-test that controls the deflation as a function of the pulse rate, the
deflation rate is between 2 mmHg/pulse and 3 mmHg/pulse.
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ISO 81060-2:2009(E)
This method shall only be used when the sphygmomanometer-under-test cuff meets the requirements of
ISO 81060-1.
The sphygmomanometer-under-test shall not deflate prior to the detection of the reference diastolic blood
pressure. The sphygmomanometer-under-test may be modified to meet this criterion.
NOTE Valid same arm simultaneous determinations require the sphygmomanometer-under-test to inflate the cuff
to at least 20 mmHg higher than the actual systolic blood pressure, as determined by the reference
sphygmomanometer, and to at least 20 mmHg below the actual diastolic blood pressure, as determined by the
reference sphygmomanometer.
Perform the following:
a) Have the observers using the reference sphygmomanometer and the sphygmomanometer-under-
test simultaneously determine the subject's blood pressure utilizing the same cuff and inflation/deflation
cycle (see Figure 1).
Key
1 double stethoscope
2 reference sphygmomanometer display
3 sphygmomanometer-under-test
Figure 1 — Illustration of same arm simultaneous method
b) Clear the sphygmomanometer-under-test memory of the previous determination and then wait at least
60 s.
EXAMPLE Switching the power off and on, removing the blood pressure module or issuing a reset command as
methods to clear any memory of the previous determination.
c) These data points are not used in the determination of accuracy.
d) Have the observers using the reference sphygmomanometer and the sphygmomanometer-under-
test simultaneously determine the subject's blood pressure utilizing the same cuff and inflation/deflation
cycle.
e) Wait at least 60 s between determinations.
f) Repeat d) and e) until the needed number of determinations have been performed.
If an individual subject is unstable during the period of the test, two valid determination pairs may be used. In
this case, additional subjects may be used to complete the method. No more than 10 % of the subjects shall
have fewer than three valid determination pairs.
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ISO 81060-2:2009(E)
All data from a subject shall be excluded if any two reference systolic blood pressure determinations differ
by more than 12 mmHg or if any two reference diastolic blood pressure determinations differ by more than
8 mmHg.
5.2.4.1.2 * Data analysis
The sphygmomanometer-under-test shall meet the following two criteria.
a) Criterion 1
For systolic and diastolic blood pressures, the mean error of determination, x , of the n individual paired
n
determinations of the sphygmomanometer-under-test and the reference sphygmomanometer for all
subjects shall not be greater than 5,0 mmHg, with a standard deviation, s , no greater than 8,0 mmHg when
n
calculated according to Equation (1) and Equation (2):
n
1
xp=× −p (1)
()
n ∑ sut ref
ii
n
i=1
n
2
1
s=× (2)
xx−
n ∑()n
i
n−1
i=1
where
x
n
is the mean error;
x = p − p of a paired blood pressure determination (sphygmomanometer-under-test −
sut ref
i
ii
reference sphygmomanometer);
i is the index for the individual element;
n is the number of determinations.
and s shall be calculated and expressed to 0,1 mmHg.
x
n
n
EXAMPLE 1 n = 255 for a sphygmomanometer intended for use in adults and/or adolescent patients (an 85 subject
study).
EXAMPLE 2 n = 255 for a sphygmomanometer intended for use in adults and/or adolescents and children aged
between 3 y and12 y (an 85 subject study).
EXAMPLE 3 n = 105 for a sphygmomanometer intended for a special intended use (a 35 subject study). The
sphygmomanometer that has a separate 85 subject study.
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ISO 81060-2:2009(E)
b) Criterion 2
For the systolic and diastolic blood pressures for each of the m subjects, the standard deviation, s , of the
m
averaged paired determinations per subject of the sphygmomanometer-under-test and of the reference
sphygmomanometer shall meet the criteria listed in Table 1 when calculated according to Equation (3):
m
2
1
s=× (3)
xx−
m ∑ n
()
j
m−1
j=1
where
is the mean error over all subjects (see Equation 1);
x
n
m is the number of subjects;
j is the index for the individual element;
x is calculated from Equation (4).
j
d
1
xp=×()−p (4)
j ∑ sut ref
kk
d
k=1
where
d is the number of determinations per subject;
k is the index for the individual element.
Table 1 — Averaged subject data acceptance (criterion 2)
Maximum permissible standard deviation, s , as function of mean error,
x
m n
mmHg
x
n
0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9
± 0, 6,95 6,95 6,95 6,95 6,93 6,92 6,91 6,90 6,89 6,88
± 1, 6,87 6,86 6,84 6,82 6,80 6,78 6,76 6,73 6,71 6,68
± 2, 6,65 6,62 6,58 6,55 6,51 6,47 6,43 6,39 6,34 6,30
± 3, 6,25 6,20 6,14 6,09 6,03 5,97 5,89 5,83 5,77 5,70
± 4, 5,64 5,56 5,49 5,41 5,33 5,25 5,16 5,08 5,01 4,90
± 5, 4,79 — — — — — — — — —
EXAMPLE For mean error of ± 4,2, the maximum permissible standard deviation is 5,49.
EXAMPLE 4 m = 85 for a sphygmomanometer intended for use in adults and/or adolescent patients (an 85 subject
study).
EXAMPLE 5 m = 85 for a sphygmomanometer intended for use in adults and/or adolescents and children aged
between 3 y and 12 y (an 85 subject study).
EXAMPLE 6 m = 35 for a sphygmomanometer intended for (an additional) special intended use (a 35 subject study).
The sphygmomanometer that has a separate 85 subject study.
EXAMPLE 7 m = 85 for a sphygmomanometer intended only for a special intended use (an 85 subject study).
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ISO 81060-2:2009(E)
5.2.4.2 * Same arm sequential method
5.2.4.2.1 Procedure
Perform the following method:
a) Have the observers using the reference sphygmomanometer determine the subject's blood pressure
(see Figure 2).
Key
1 double stethoscope
2 reference sphygmomanometer display
3 reference sphygmomanometer hand pump
4 sphygmomanometer-under-test
Figure 2 — Illustration of same arm sequential method
b) Wait at least 60 s.
c) Have the observers using the sphygmomanometer-under-test determine the subject's blood pressure.
d) Clear the sphygmomanometer-under-test memory of the previous determination and then wait at least
60 s.
EXAMPLE Switching the power off and on, removing the blood pressure module or issuing a reset command as
methods to clear any memory of the previous determination.
e) These data points shall not be used in the determination of accuracy.
f) The starting order [see g)] of sphygmomanometer-under-test and reference sphygmomanometer
determinations shall be alternated between subjects, or a randomizations procedure may be used to
determine the starting order.
g) Have the observers using the reference sphygmomanometer and the sphygmomanometer-under-
test determine the subject's blood pressure sequentially.
h) Wait at least 60 s between each determination.
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ISO 81060-2:2009(E)
i) Repeat g) and h) until the needed number of determinations has been performed.
All data from a subject shall be excluded if any two reference systolic blood pressure determinations differ
by more than 12 mmHg or if any two reference diastolic blood pressure determinations differ by more than
8 mmHg.
5.2.4.2.2 Data analysis
The sphygmomanometer-under-test shall meet the following two criteria.
a) Criterion 1
For systolic and diastolic blood pressures, the mean error of determination, x , of the n individual paired
n
determinations of the sphygmomanometer-under-test and the reference sphygmomanometer for all
subjects shall not be greater than 5,0 mmHg, with a standard deviation, s , no greater than 8,0 mmHg when
n
calculated according to Equation (5) and Equation (6):
n
1
xp=× −p (5)
()
n ∑ sut ref
ii
n
i=1
n
2
1
s=× (6)
xx−
n ∑()n
i
n−1
i=1
where
is the mean error;
x
n
x = p − p of a paired blood pressure determination (sphygmomanometer-under-test − reference
i sut ref
sphygmomanometer);
n is the number of determinations.
The p or reference sphygmomanometer determinations shall not be the average of the preceding and
ref
following reference blood pressures. x and s shall be calculated and expressed to 0,1 mmHg.
n n
EXAMPLE 1 n = 255 for a sphygmomanometer intended for use in adults and/or adolescent patients (an 85 subject
study).
EXAMPLE 2 n = 255 for a sphygmomanometer intended for use in adults and/or adolescents and children aged
between 3 y and 12 y (an 85 subject study).
EXAMPLE 3 n = 105 for a sphygmomanometer intended for a special intended use (a 35 subject study).
b) Criterion 2
For the systolic and diastolic blood pressures for each of the m subjects, the standard deviation, s , of the
m
averaged paired determinations per subject of the sphygmomanometer-under-test and of the reference
sphygmomanometer, shall meet the crit
...
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