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Welcometo the Spirometry Course

Developed by:• Felip Burgos: Hospital Clínic of Barcelona •Jordi Giner: Hospital de la Santa Creu i Sant Pau of Barcelona•SIBELMED

Barcelona 2015

Let's Begin

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Let's Begin

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Spirometry HistorySpirometry History

Let's Begin

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History of SpirometryHistory of Spirometry

Etymologically, spirometry meansthe measurement of breath or breathing.The term is attributed to Lavoisier (1862),

who discovered oxygen and gave it its name.

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Galen (AD 129-200)Doctor and Greek philosopher

First Attempt to Measure Lung Capacity

In his experiment, he asked a child to breath into a bladder, observing that the volume entering the bladder did not vary with each breath.

(he did not record any measurements).

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John Hutchinson (1811-1861) Inventor of the spirometer.

The First Spirometer

• Born in Newcastle

• He studied medicine at the University of London and surgery at Southampton.

• He worked for 2 years at London Brompton Hospital, where he developed his spirometry working theories and principles (1846).

• As we know it today, spirometry was developed by him when designing the spirometer model.

He made more than 4000 spirometers

He made more than 4000 spirometers

He made more than 4000 spirometers

He made more than 4000 spirometers

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John Hutchinson (1811-1861)

He observed that the volume of air that could be exhaled from the lungs when completely inflated (Vital Capacity or VC) was a good indicator of an individual's longevity.

When this measure was compromised, premature death was expected. (PROGNOSIS VALUE).

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Other Early Spirometers

Spirometer made in 1850 (Pixxi Family, Paris 1850) and by Dr. S.W. Mitchell (1859).

Portable Spirometers(Circa 1900).

Water Spirometer (Godart, 1960)

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Unknown Author / Fons Escuela ClaretUnknown Author / Fons Escuela Claret

First Spirometry Performed at Hospital de la Santa Creu i Sant Pau.

(Barcelona 1958)

First Spirometry Performed at Hospital de la Santa Creu i Sant Pau.

(Barcelona 1958)

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Ventilation Diagram8

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4

2

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FRC: Functional Residual Capacity

TLC: Total Lung Capacity

VC: Vital Capacity

IRV: Inspiratory Reserve Volume

Vt: Tidal VolumeERV: Expiratory Reserve VolumeRV: Residual Volume

What is Spirometry?

• It is useful for studying respiratory problems (asthma, COPD, etc.) and to evaluate possible occupational pulmonary disorders.

• Spirometry is a test which is essential to study lung function. It measures the volume of air moved during a maximum and forced exhale.

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Spirometry

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VEMS: Volume Expiratoire Maximum Seconde (Maximum Expiratory Volume in one Second) FEV1: Forced Expiratory Volume in the first Second

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COPDChronic Obstructive Pulmonary Disease is characterized by a chronic and irreversible obstruction of the airflow caused, mainly, by an inflammatory reaction to tobacco smoke. (GOLD; GESEPOC)

ASTHMAChronic respiratory disease characterized by the inflammation of the airways, hyperresponsive to a wide variety of stimuli and reversible bronchial obstruction. (GINA; GEMA)

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Volume (L)

Types of Spirometer

According to their properties

•Water / Dry•Closed / Open•Volumetric / Pneumotachometer

The most used are Pneumotachometers (Open)

Types of Pneumotachometer:•Lilly•Fleisch•Turbine•Ultrasonic•Venturi•Other: Hot wire, Pitot, etc....

According to their use

•Pulmonary function laboratories•Patient screening

Tachometer: From the Greek τάχος, tachos, ‘velocity’ and μέτρον, metron, ‘measure’(In some bibliographies the pneumotachometer is referred to as pneumotachograph)

Characteristics (pneumotachometers)•They are the open type•They are flow sensors•Flow-time relation•Calculate volumes by microprocessor•Different types of curves:• Volume/Time• Flow/Volume

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• Measure a minimum volume of 8 liters and a flow of 0 to 14 l/s

• Measure a volume with a minimum precision of ± 3% or ± 50ml (whichever is better)

• Signal accumulation during 30"

• Resistance to a 14 l/s flow less than 1.5 cmH2O

• Assessment of the start of the maneuver by retrograde extrapolation

• Simultaneous graph-plotting

• Measure a minimum volume of 8 liters and a flow of 0 to 14 l/s

• Measure a volume with a minimum precision of ± 3% or ± 50ml (whichever is better)

• Signal accumulation during 30"

• Resistance to a 14 l/s flow less than 1.5 cmH2O

• Assessment of the start of the maneuver by retrograde extrapolation

• Simultaneous graph-plotting

Spirometer Requirements

Water Bell SpirometerWater Spirometer

The bell moves when exhaling

Moves the paper and

marker

Results are plotted

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Bellows Spirometer

• Registers the forced expiration.• The most used spirometer until the

pneumotachometer.When exhaling the bellows inflate

Moves the paper and

markerThe results

appear

Closed and Dry Type

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Piston Spirometer

• Sealed cylinder prevents air escaping.

Moves the paper, and plots results

Closed and Dry Type

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When exhaling, the piston and marker move

Pneumotachometer diagramLILLY

A: Resistance B: Pressure sensor or differential transducer

The differential transducer measures the pressure before the resistance (P1) and after the resistance (P2) to calculate the flow; using integration of the flow the volume is obtained.

Measurement based on the difference in air-flow pressure before and after passing through a known RESISTANCE (screen (A)), which is directly proportional to the airflow that passes through a PRESSURE SENSOR. Once the flow is obtained, the microprocessor calculates the volumes by mathematically integrating the flow with the time function.

LILLY Pneumotachometer (operating principle)

Disposable Lilly Pneumotachometer

P1P1 P2

P2

BB

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Avoids cross contamination

A: Resistance B: Pressure sensor or differential transducer

The differential transducer measures the pressure before the resistance (P1) and after the resistance (P2) to calculate the flow; using integration of the flow the volume is obtained.

Pneumotachometer diagramFLEISCH

P1P1 P2

P2

BB

AA

Measurement based on the difference in airflow pressure before and after passing through a known RESISTANCE (capillaries arranged in parallel(A)), which, is directly proportional to the flow of that passes through a PRESSURE SENSOR. Once the flow is obtained, the microprocessor calculates the volumes by mathematically integrating the flow with the time function.

FLEISCH Pneumotachometer (operating principle)

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The transduction function is performed in two stages:

1. The volume to be measured passes through the turbine and causes the rotor to turn proportionally.

2. The turn is detected by a break in an infrared light beam, whose sensor converts the light received into a digital electrical signal.

The TURBINE spirometer acquires physical signals and processes the information that the signal provides in relation to the pulmonary function. During the process, physical energy is converted into electrical energy. The units that produce this change are called transducers.

TRANSMITTER

RECEIVER

ROTATION

TURBINE (operating principle)

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A

B

C

To calculate the flow, these transducers use the ultrasonic wave property: when they form a certain angle with respect to the flow direction, ultrasonic waves that travel in the same direction as the flow take less time to arrive to the receiver than those traveling in the opposite direction.

Ultrasonic (operating principles)

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Spirometry GraphsSpirometry Graphs

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Volu

me

(L)

Volume (L)

Spirometry

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Volume (L)

Contribution of both graphs

Volu

me

(L)

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Check the quality of the maneuver

Check for correct end

Ensure that the start was sudden and

without hesitation

Ensure that the start was sudden

and without hesitation

Functional Alterations:•Obstruction•No Obstruction

Functional Alterations:•Obstruction•No Obstruction

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Lungs

Airway inasthma

Airway in COPDNormal airway

Muscle smooth still

relaxed

Inflamed wall

Relaxed smooth muscle

Inflamed and swollen

wall

Air trapped in the alveolus

Contracted smooth muscle

Bronchus

Lung of a healthy person

Lung of the same person with COPD

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Volume (L)

Spirometry

“Normal”Airway

Time (s)

Volu

me

(L)

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Volume (L) Time (s)

Volu

me

(L)

Spirometry

ObstructedAirway

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Volume (L) Time (s)

Volu

me

(L)

Spirometry

NON-Obstructive Airway

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Volume (L) Time (s)

Volu

me

(L)

Spirometry

MixedAirway

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Spirometry parameters Spirometry parameters

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Time (s)

Volu

me

(L)

FVCFEV1

Spirometric ParametersFVC : Forced Vital Capacity (FVC)Volume of air expelled during a forced expiration maneuver (L).

FEV1:

Forced Expiratory Volume in the first second.

FEV1/FVC :

Expresses the volume of air expelled in the first second with respect to the maximum that can be expelled during the forced expiration maneuver.

FEV6:

Forced Expiratory Volume in the sixth second (L).

Forced Spirometry

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FEV6

Volume (L)

Spirometric Parameters

PEF (Peak Flow)

•Maximum expiratory flow or peak flow.

•Maximum flow achieved during the forced expiration maneuver.

•It is generated before having expelled 15% of the FVC and must be maintained for a minimum of 10 ms (milliseconds)

•Expressed in L/sec.

•Effort-dependent parameter.

PEF

Forced Spirometry

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Volume (L)

Spirometric Parameters

FEF 50 %

Maximum flow when the 50% of the FVC has been exhaled.

FEF 25-75 %

Maximum flow between 25% and 75% of the FVC (mid-expiratory flows).

Mid-expiratory flows may early detect obstruction (in the small tract), but they are highly variable.

FEFFEF 25

FEF 50

FEF 75

Forced Spirometry

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Time (s)

Volu

me

(L)

Spirometry

ObstructedAirway

FVC ≈ FEV6 Inflamed and swollen wall

FEV1

FVC

FEV1

1 sec

6 sec

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FEV6

6 sec

In patients with an obstruction in the airflow, the expiratory maneuver can be tedious and prolonged, have insufficient relevance and wide variability; therefore, specific authors and consensus suggest that, in these cases, the value of FEV6 (forced expiratory volume in the sixth second) is comparable to the FVC. Likewise, the ratio FEV1/FVC would be replaced by FEV1/FEV6.

FVC ≈ FEV6

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On the screen we can see selected some of the 'most significant' parameters. The other parameters, although important, have less relevance.

Which parameters should we focus on?

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Time (s)

Volu

me

(L)

Volume (L)

“Normal” Spirometry

PEFFVC

FEV1

FEV1 3.9 (L)FVC 5.0 (L)FEV1/ FVC 78%

CurveVolume / Time

CurveFlow / Volume

FVC

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Between 70% and 80%

> 80% reference value

Time (s)

Volu

me

(L)

Volume (L)

PEF

FVC

FEV1

FEV1 1.5 (L)FVC 4.0 (L)FEV1/ FVC 38%

CurveVolume / Time

CurveFlow / Volume

FVC

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Less than 70%

“Obstructive” Spirometry

Volume (L)

COPDChronic Obstructive Pulmonary Disease is characterized by a chronic and irreversible obstruction of the airflow caused, mainly, by an inflammatory reaction to tobacco smoke (GOLD, GESEPOC).

SpirometryProgression of the Obstruction

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COPDCOPD

Time (s)

Volu

me

(L)

Volume (L)

PEF

FVC

FEV1

FEV1 1.8 (L)FVC 1.9 (L)FEV1/ FVC 95%

CurveVolume / Time

CurveFlow / Volume

FVC

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Greater than 80%

“NON-Obstructive” Spirometry

Instructions and Limitations

Instructions and Limitations

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Reference Values(Also denoted THEORETICAL)

Reference Values(Also denoted THEORETICAL)

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Reference Values (theoretical)

Objective:Compare the measured values with the

corresponding values of Sex, Age, Size, Weight and Ethnicity.

Material (reference equations): FVC: M 0.028 T + 0.0345 P + 0.0573 E - 3.21F 0.0305 T + 0.0356 P + 0.0356 E - 3.04

Method:The observed / reference values expressed

as a %.

ANTHROPOMETRY

ANTHROPOMETRY

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Reference Values (theoretical)

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Recommended spirometric reference values in our environment

Parameter Measuring Method

Parameter Measuring Method

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Expressing resultsThe results are expressed as a % with respect to the reference value

% Vref = Vobs/Vref x 100(The percentage of the reference value is equal to the observed value divided by the reference value multiplied by 100)

The 95% confidence interval or 95 percentile are the same; they calculate the lower limit of the normal distribution (LIN) using the formula: LIN = VR - SEE x 1.645

99.7%95.4%68.3%

µ-3ơ µ-2ơ µ-ơ µ µ+ơ µ+2ơ µ+3ơ

Dispersion around the prediction equation

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Performing SpirometryPerforming Spirometry

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Decaloguefor Performing Spirometry

TRAININGthe expert that will perform the spirometry and having notions of respiratory pathologies.

QUALITY CONTROLDaily verification, with a known pattern, the correct operation of the spirometer, since this proves that it is functioning within the established limits.

The daily verification and/or calibration (with a syringe of at least three liters) ensures verifiable quality control and confirms professional good practice.

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Objective:• To establish a relationship between the pattern unit (syringe) and the degrees of measurement.

Material:

• Syringe (At least three liters).

• Weather station (Quality spirometers already have one incorporated; otherwise, use conventional wall or desktop stations).

Quality control (calibration)

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Method:•Daily calibration.•High, moderate and low flow *.

Quality control (calibration)

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To verify the correct operation of a spirometer, carry out a single maneuver at moderate flow: from 2 to 5 l/s.However, ideal verification/calibration to ensure good practice should carry out high, moderate and low flows.

To verify the correct operation of a spirometer, carry out a single maneuver at moderate flow: from 2 to 5 l/s.However, ideal verification/calibration to ensure good practice should carry out high, moderate and low flows.

* Flow LevelLow: From 0.4 to 1.2 l/sModerate: From 2 to 5 l/sHigh: From 6 to 12 l/s

* Flow LevelLow: From 0.4 to 1.2 l/sModerate: From 2 to 5 l/sHigh: From 6 to 12 l/s

Another method of representing the calibration depending on the make and

model of the equipment.

Quality controlPerforming Verification/Calibration

ESP. 2 . 1 %F l o w M . 1 . 8 l / s

I NSP. 3 . 0 %

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3 INFORMThe patient of the procedure to follow, the reasons behind it and how to avoid problems, as well as of the importance of their cooperation.

AVOIDBefore taking the test:

•Prior administration of bronchodilators. If they have been administered, this should be recorded.

•Smoking.

•Vigorous exercise.

•Excessive eating and/or drinking.

•Tight clothing.

Pharmaceuticals to stop taking and duration Hours

Agonist ß2 short-acting 6

Agonist ß2 long-acting 12

Anticholinergics short-acting 6

Anticholinergics long-acting 24

Sustained release theophylline 36 - 48

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FIND OUTThe size and weight of the patient with their shoes off and wearing light clothing, as well as their age and sex, in order to calculate the reference values.

For patients with acute chest deformity, measure their breadth instead of their size (arms extended in a cross); this should be registered in the report.

BreadthHow to calculate the breadth

Size = Breadth/ 1.06

SEAT The patient in a comfortable chair with vertical back support and do not incline them forwards.

•Seat the patient with their head up and legs uncrossed.

•Keep the nostrils occluded using nose clips.

•Place the mouthpiece into the transducer, bacterial filter or disposable transducer (only use certified products).

•If the test is carried out with the patient lying flat, this must be noted.

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EXPLAINIn a clear and simple way how to perform the spirometry maximum and forced maneuvers.

1. Inhale as much as possible2. Place the mouthpiece into your mouth3. Blow:

1. STRONGLY2. CONTINUALLY3. WITHOUT STOPPING UNTIL I SAY SO:it may seem that there is no more air to come out,

but there is, I control it through the screen

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Encourage

When performing spirometry, it is essential to encourage the patient so that the maneuver will be valid; they need to cooperate in order to achieve a sudden, maximum and prolonged effort. (6 seconds).

more

Time (s)

Volu

me

(L)

CurveVolume / Time

Blow

Modern spirometers incorporate incentives which are very useful in meeting this objective.

Very good

PERFORM1.A slow, maximum inhalation, pause < 1 sec.2.Maximum expiration, quick and forced with a sudden start.•Perform a minimum of 3 and a maximum of 8 maneuvers, ensuring that 2 of them are error-free and that the FVC and the FEV1 differences are less than 5% or 150ml (100 if the FVC is less than 1 liter).•The duration time for each maneuver should not be less than 6 seconds (3 seconds for children).3.Check the lines.

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The maneuver line is characterized by the absence of bumps and dips.

A concave curve should be drawn.

Characteristics of the Maneuver Line

• Without bumps

• Without dips

Concaved curve

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More than eight maneuvers tire the patient and will make it difficult to obtain better values.

Repeat Criteria

Three (3) acceptable maneuvers, in a maximum of

eight (8) that comply with these criteria:

The difference between the best two, for the FVC and the

FEV1, should be less than 5% or 150ml

(100 ml if the FVC < 1 liter).

Less than three maneuver may cause errors due to lack of patient training.

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Retrograde extrapolation is the method recommended to find the zero time point (start of the maneuver).

Retrograde Extrapolation

Time (s)

Extrapolated volume

0 time point

The volume-time spirometry maneuver extends the time and volume base lines (blown-up diagram) and the cutoff point is the extrapolated zero time point.

Volu

me

(L)

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Note:The extrapolated volume should be equal to or less than 150ml or 5% of the FVC (the better of the two criteria).

Modern spirometers automatically calculate it and, should the value be exceeded, give a maneuver error message.

The start of the maneuver should be quick, sudden and without hesitation.

Initial Criteria

Time (s)

Volu

me

(L)

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Correct Start

Maneuver with a poor start.

Maneuver with a correct start.

Initial Criteria

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• Maneuver time longer than 6 sec.

Incorrect curve, finished quickly.

• No changes for 1 sec; volume less than 25ml.

Maneuver with a good finish.

Finalization Criteria

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9 SELECTThe best FVC and FEV1 values even if they come from different maneuvers; but they meet the previous criteria.

The rest of the parameters are taken from the maneuver with the greater sum of FVC and FEV1 .

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Ideally, choose parameters from error-free maneuvers (no warnings), although in many cases this is difficult.

Once the maneuvers have been performed, report the best FVC and the best FEV1 , even though they may come from different maneuvers.

The rest of the parameters are taken from the maneuver with the greater sum of the FVC and the FEV1 . In the majority of modern equipment these criteria are automatically applied.

Choose the best FVC and FEV1 values, even if they come from different maneuvers.

Which Parameters Should be Reported?

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NLHEP(National Lung Health Education Program)

Quality Grades

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SEPAR – PÉREZ PADILLA

Bronchodilation testContracted

smooth muscle

Inflamed and swollen

wall

Air trapped in the alveolus

Airway in asthma

Relaxed smooth muscle

Bronchodilated airway

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The test is considered positive if it produces an increase equal to or greater than:• FVC: 12% or FEV1: 12% • and additionally, a minimum of 200 ml

PREPOST

4 inhalations (with camera)

Inhale bronchodilator

10CLEANINGGiven that the transducer is directly exposed to the patient, it must be kept in perfect physical and hygienic conditions.

Clean and disinfect it as per the manufacturer's instructions. If this is not possible use soap and water and, wherever possible, sterilize periodically the pieces exposed to the patient.

For potentially contagious patients (HIV+, hepatitis C, pulmonary tuberculosis, etc.), use single-use pneumotachometers or carry out the test at the end of the day using antibacterial filters. Then, proceed to clean it thoroughly.

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Let's Begin

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Thank You

Thank You