alveoflow® - alveofit

Why oscillometry

Some patients cannot produce an acceptable forced manoeuvre.

Spirometry depends on maximal effort and a repeatable technique. Oscillometry does not — it measures during the breathing the patient is already doing. That difference decides who you can test, and how often.

Forced manoeuvre required

Maximal inspiration, then a hard, fast, sustained blow
Coaching, repeat attempts, acceptability and repeatability criteria
Difficult in young children, frail or elderly patients, and anyone breathless at rest
Effort artefact is a common cause of an uninterpretable test

Tidal breathing only

Patient breathes quietly through the mouthpiece for 15–30 seconds
No coaching, no maximal effort, no learned technique
Viable where spirometry is not, including serial testing in the same visit
Resolves resistance separately at low and high frequency

Oscillometry complements spirometry; it does not replace it. Where both are indicated, the alveoflow® runs the pair in one sitting, which is the reason for putting them on one platform.

What it measures

Six parameters, and what each one tells you.

Select a parameter to locate it on the spectrum.

Impedance spectrum R5 · total respiratory resistance

Resistance R(f) Reactance X(f) kPa·s·L⁻¹

R5 — total respiratory resistance

Resistance measured at 5 Hz. The low-frequency signal reaches the whole airway tree, so R5 reflects total resistance — central and peripheral together. Raised R5 indicates obstruction somewhere in the system; on its own it does not say where.

Output

What comes back after a test.

Pre- and post-bronchodilator values side by side, with the change expressed against the reference set in use.

Oscillometry — pre / post bronchodilator Reference set: to be confirmed · Illustrative values

R5: 0.45 kPa·s·L⁻¹
R5–R20: 0.12 kPa·s·L⁻¹
X5: −0.18 kPa·s·L⁻¹
AX: 1.9 kPa·L⁻¹

Values shown are illustrative and do not represent a specific patient. Interpretation is the responsibility of the treating clinician.

Specifications

Both modules, in full.

Method	Forced Oscillation Technique (FOT) / respiratory oscillometry
Excitation	Hybrid pseudo-random and chirp waveform
Frequency range	5–40 Hz (optional extension to 60 Hz)
Parameters reported	R5, R20, R5–R20, X5, AX, Fres, intra-breath resistance and reactance loops
Acquisition time	15–30 s tidal breathing
Repeatability	±3% resistance, ±5% reactance
Accuracy	<2% deviation against reference loads
Sampling	400 Hz acquisition, 24-bit
Calibration	Automated pre-test calibration. Verification against supplied reference load
Reference equations	To be confirmed
Patient range	Adult and paediatric — state minimum validated age

Method	Forced spirometry, same mouthpiece and flow head
Parameters	FVC, FEV1, FEV1/FVC, PEF, FEF25–75, FEV6
Volume range	0–8 L
Flow range	±16 L/s
Volume accuracy	±2.5% or ±0.050 L, whichever is greater
Flow accuracy	±5% or ±0.200 L/s, whichever is greater
Validation	ATS 24-waveform profile set
Reference equations	To be confirmed

Display	10-inch capacitive touchscreen
Connectivity	Wi-Fi, Bluetooth 5.3, USB-C, optional Ethernet
Software	alveoSenseAI™ analysis and alveoConnect® platform
EMR integration	HL7 v2 and FHIR R4
Security	AES-256 in transit and at rest. Data regime to be stated
Operating environment	10–45 °C, 10–90% RH non-condensing
Noise level	<20 dBA
Dimensions / weight	To be added
Power / battery	To be added
Consumables	Mouthpiece, bacterial/viral filter — specify type and dead space
Warranty / service	To be added
Radio	FCC ID 2AV9TD8-52832-01

Clinical applications

Where it is used.

Settings

Pulmonology clinics Hospitals Diagnostic laboratories Respiratory care centres Occupational health Clinical research

Assessments

Asthma COPD Small-airway dysfunction Bronchodilator response Pulmonary function evaluation Longitudinal monitoring

Standards and evidence

What the system is built and tested against.

Technical standards

Oscillometry: ERS technical standard on respiratory oscillometry — King GG et al., Eur Respir J 2020;55:1900753
Spirometry: ATS/ERS standardisation of spirometry, 2019 update — Graham BL et al., Am J Respir Crit Care Med 2019;200:e70–e88
Electrical safety: IEC 60601-1 series
Biocompatibility: ISO 10993 series
Quality system: ISO 13485, MDSAP

Validation

A paired method-comparison study against a reference oscillometry system is in progress. Bland–Altman agreement and repeatability data are available to clinicians and evaluators on request.

Request the validation summary →

Questions

Frequently asked.

What is respiratory oscillometry?

A small pressure oscillation is applied at the mouth while the patient breathes normally. Measuring the resulting pressure and flow gives respiratory impedance, which separates into resistance and reactance at each frequency tested.

Does it replace spirometry?

No. The two measure different things — spirometry measures volumes and flows during a forced manoeuvre; oscillometry measures the mechanical properties of the airways during tidal breathing. They are complementary.

What do R5–R20 and AX tell me?

R5–R20 is the difference between low- and high-frequency resistance. A widened gap points to peripheral rather than central obstruction. AX is the area bounded by the reactance curve below zero up to the resonant frequency.

What is the minimum age for testing?

To be confirmed — state the minimum age this device is validated for, rather than “paediatric”.

How long does a full assessment take?

To be confirmed — give the timing for oscillometry alone, and for a pre/post bronchodilator pair.

What are the infection control requirements?

To be confirmed — name the filter, state whether the mouthpiece is single-use, and list validated cleaning agents.

How do results reach our EMR?

Results are exported over HL7 v2 or FHIR R4 via the alveoConnect® platform, or as PDF to a shared location. A sandbox is available for integration testing before purchase.

Is it available in the United States?

Not currently. A 510(k) submission is pending and the device is not cleared for sale in the United States. It is available in India under CDSCO Class B, and in other markets on a country-by-country basis.