THERA-HEAT HEATED HUMIDIFIER AND ADULT DUAL AND SINGLE LIMB HEATED WIRE VENTILATOR BREATHING CIRCUITS
K071958 · Smiths Medical Asd, Inc. · BTT · Nov 21, 2007 · Anesthesiology
Device Facts
Record ID
K071958
Device Name
THERA-HEAT HEATED HUMIDIFIER AND ADULT DUAL AND SINGLE LIMB HEATED WIRE VENTILATOR BREATHING CIRCUITS
Applicant
Smiths Medical Asd, Inc.
Product Code
BTT · Anesthesiology
Decision Date
Nov 21, 2007
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 868.5450
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
The Smiths Medical Thera-Heat™ Heated Humidifier device is intended to warm and add humidity to the breathing gases that are administered to the patient. The humidifier is indicated for patients requiring mechanical ventilation, positive pressure breathing assistance of general medical gases. The Smiths Medical Thera-Heat™ Heated Humidifier device is intended for use in hospitals and alternate sites by medically trained healthcare providers. An adult ventilator Heated Breathing Circuit is intended to warm breathing gases before they enter a patient's airway when used with the Thera-Heat™ Heated Humidifier. The circuit acts as a conduit to warm the gases between the humidification chamber and the patient during mechanical ventilation or positive pressure breathing assistance for use with invasive and noninvasive breathing systems. An adult ventilator Heated Breathing Circuit is intended to warm breathing gases before they enter a patient's airway and to warm the breathing gases on return from the patient to the ventilator when used with the Thera-Heat™ Heated Humidifier. The circuit acts as a conduit to warm the gases between the humidification chamber and the patient during mechanical ventilation or positive pressure breathing assistance for use with invasive and non-invasive breathing systems.
Device Story
Thera-Heat™ Heated Humidifier system adds moisture and heat to breathing gases for patients on mechanical ventilation or positive pressure support. System uses passover humidification: dry gas passes over warmed water in an auto-fill chamber with integral float valve. Controller unit manages heating of humidification chamber and optional heated breathing circuits (single or dual limb). Clinician sets desired airway temperature and humidity index; controller maintains temperature gradient to reduce condensation/pooling. Accessories include water chambers, temperature probes, and interface cables. Used in hospitals/alternate sites by trained providers. Benefits include preventing airway irritation and desiccation of secretions by providing warmed, humidified gas.
Clinical Evidence
Bench testing only. No clinical data required. Testing included mechanical, electrical, and software functional performance, temperature accuracy, electromagnetic immunity, and compliance with safety standards (IEC60601-1, UL60601-1, CAN/CSA 22.2 No.60601.1, IEC60601-1-2, IEC60601-1-4, ASTM F1690, ISO 8185).
Indicated for patients requiring mechanical ventilation or positive pressure breathing assistance of general medical gases. Used in hospitals and alternate sites by medically trained healthcare providers.
Regulatory Classification
Identification
A respiratory gas humidifier is a device that is intended to add moisture to, and sometimes to warm, the breathing gases for administration to a patient. Cascade, gas, heated, and prefilled humidifiers are included in this generic type of device.
Cardinal Health (formerly Allegiance Healthcare Corp) Airlife® Heated Ventilator and Anesthesia Breathing Circuits (K000697)
Submission Summary (Full Text)
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K071958 Page 1 of 4
# smiths medical
bringing technology to life
Smiths Medical ASD Inc. Critical Care Division 160 Weymouth Street Rockland, MA 02370, USA
www.smiths-medical.com
T: +1 781 878 8011 F: +1 781 878 8201
SECTION 5, 510(k) Summary
### Company Information:
Smiths Medical ASD, Inc. 160 Weymouth Street Rockland, MA 02370 (781) 878-8011, ext 7904 Contact: Christine A. Lloyd Regulatory Affairs Specialist
Summary Prepared: November 21, 2007
NOV 2 1 2007
#### Product Name:
#### Trade Name: Thera-Heat™ Heated Humidifier and Heated WireVentilator Breathing Circuits
Common Name: Respiratory Gas Humidifier and Heated Wire Ventilator Breathing Circuits.
Classification Name: Humidifier, Respiratory Gas Heater (21 CFR 868.5450, Product Code BTT) & Breathing System (21 CFR 868.5270, Product Code BZE)
#### Predicate Device(s):
K913368, (Fisher & Paykel Electronics Ltd.) Models MR700/MR720/MR730 Dual Servo Respiratory Humidifier ACC ---
K000697, JCardinal Health (formerly Allegiance Healthcare Corp), Airlife® Heated Ventilator and Anesthesia Breathing Circuits
#### Device Description:
#### Thera-Heat™ Heated Humidifier
The Thera-Heat™ Heated Humidifier system is a respiratory gas humidifier according to 21 CFR §868.5450. A respiratory gas humidifier is identified by the Food and Drug Administration (FDA) as a therapeutic device that is intended to add moisture and if applicable, heat to breathing gases prior to administration to a patient. Indirect heating is used by the Thera-Heat™ to provide an evaporated water content to dry breathing gases.
Respiratory gas humidifiers are used by clinicians to raise the water content of gases delivered to patients. Gases available for medical use do not always have sufficient moisture and may damage or irritate the respiratory tract or desiccate tracheobronchial secretions of patients whose airways have been bypassed. The Thera-Heat™ Heated Humidifier system warms and adds
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water vapor to the inspired gas by heating water within the humidification chamber as the dry gas passes over the warmed water.
The humidification chamber is an auto-fill style that contains an integral float valve at the water filling port. The float valve regulates the water level inside the chamber to maintain a constant water level. The water supply (liquid reservoir) is a pre-filled sterile water reservoir that connects to a filling port on the humidification chamber. When the liquid reservoir is empty, the caregiver will exchange it with a new one. After the gas is warmed and humidified it is channeled to the breathing tube for delivery to the patient.
The system can be operated using a conventional breathing tube (non-heated) in both limbs, or a heated breathing tube in the inspiratory limb only, or a heated breathing tube in both limbs. The heating of the humidification chamber and the power supplied to the heated breathing tube is provided by the controller unit. The purpose of the heated breathing tube is to regulate the gas temperature from the humidification chamber to the patient, reducing condensation and pooling of water, and the means of controlling the relative humidity by maintaining a temperature gradient between the humidification chamber and the delivered airway temperature. The caregiver sets the controller unit to the desired patient airway temperature, and then sets a humidity index value, which is limited in range by the controller based on the desired patient airway temperature. The control unit will maintain the selected temperature for the patient airway and the humidification chamber output temperature based on the humidity index value.
Accessories for the Thera-Heat™ Heated Humidifier include the humidification (water) chambers, temperature probes, interface cables and brackets.
#### Heated Wire Ventilator Breathing Circuits
A heated Wire Ventilator Breathing Circuit is a disposable device compromised of 22mm corrugated plastic tubing, 22 mm plastic tube connectors, and an electrical heater-wire harness subassembly. After the gas is warmed and humidification chamber it is delivered through the inspiratory limb of the breathing circuit to the patient. Heating of the breathing tube is provided and controlled by the heated humidifier. The heated wire breathing circuits may be comprised of a dual limb or single limb circuit. The purpose of the heated wire ventilator breathing circuits is to maintain or raise the gas temperature to or above the dew point reducing or eliminating water condensation and/or pooling of water in the breathing circuit. Other accessories such as exhalation valves, water traps, etc. can be added in to the overall assembly creating different product variations.
#### Indications for Use:
#### Thera-Heat™ Heated Humidifier
The Smiths Medical Thera-Heat™ Heated Humidifier device is intended to warm and add humidity to the breathing gases that are administered to the patient. The humidifier is indicated for patients requiring mechanical ventilation, positive pressure breathing assistance of general medical gases
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The Smiths Medical Thera-Heat™ Heated Humidifier device is intended for use in hospitals and alternate sites by medically trained healthcare providers.
#### Inspiratory heated limb
An adult ventilator Heated Breathing Circuit is intended to warm breathing gases before they enter a patient's airway when used with the Thera-Heat™ Heated Humidifier. The circuit acts as a conduit to warm the gases between the humidification chamber and the patient during mechanical ventilation or positive pressure breathing assistance for use with invasive and noninvasive breathing systems.
#### Inspiratory and Expiratory heated limbs)
An adult ventilator Heated Breathing Circuit is intended to warm breathing gases before they enter a patient's airway and to warm the breathing gases on return from the patient to the ventilator when used with the Thera-Heat™ Heated Humidifier. The circuit acts as a conduit to warm the gases between the humidification chamber and the patient during mechanical ventilation or positive pressure breathing assistance for use with invasive and non-invasive breathing systems.
#### Technological Characteristics:
The technological characteristics of the Thera-Heat™ Heated Humidifier are equivalent to the predicate device; Fisher & Paykel Electronics Ltd, Models MR700/MR720/MR730 Dual Servo Respiratory Humidifier ACC per K913368. The Thera-Heat™ is equivalent to the Fisher & Paykel humidifiers in terms of:
| Type: | Active Heated Humidifier |
|------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Humidification method: | Passover humidification |
| Configuration: | Humidification chamber, heated wire or non-heated breathing<br>circuits, and a dual sensor temperature probe to monitor the<br>humidification chamber output temperature and temperature of<br>the airway proximal to the patient connection port. |
| Control: | Comparable range of temperature and humidity adjustments |
| Control method: | Software controlled using a microcontroller |
#### Non-Clinical Data:
Non-clinical testing of the Thera-Heat™ Heated Humidifier has been carried out covering mechanical, electrical, and software for functional performance and temperature accuracy under environmental conditions and tests standards for electromagnetic immunity.
The Thera-Heat™ Heated Humidifier meets the safety requirements of IEC60601-1, UL60601-1, and CAN/CSA 22.2 No.60601.1. It meets the electromagnetic compliance requirements of IEC60601-1-2 and the software compliance of IEC60601-1-4 to the acceptance of Underwriters Laboratories. The Thera-Heat™ Heated Humidifier complies with the performance and safety
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standards ASTM F1690 (USA) and ISO 8185 for active humidification with the following two exceptions. Clause 51.6.2 the Thera-Heat™ generates a high priority alarm in the event that the airway temperature is at or above 41°C. Clause 51.8 part C, the Thera-Heat™ cannot reduce the airway temperature sufficiently when the air flow is increased (instantaneously) from the minimum rated flow to the maximum rated flow and the airway temperature is being regulated through a non-heated (non-wire) breathing circuit. This event does cause the Thera-Heat™ to generate an alarm and stops the heating of the humidification chamber however it cannot prevent the airway temperature from exceeding 43°C for 30 seconds (ISO8185 clause 51.8); this is because energy in the water was created for the lower flow. We have placed a warning label on the outside of the device and in the operator's manual to provide some risk control over this situation for the user.
#### Clinical Data:
Not required
#### Conclusion:
The standards compliance and product performance testing conducted demonstrates that the proposed device is safe and effective and is substantially equivalent to the predicate device.
Very truly yours,
SMITHS MEDICAL ASD, INC.
Nudesthe A. Lloyd
Christine A. Lloyd Regulatory Affairs Specialist
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Image /page/4/Picture/1 description: The image shows the logo for the Department of Health and Human Services (HHS). The logo features a stylized eagle with three lines forming its body and wings. The text "DEPARTMENT OF HEALTH AND HUMAN SERVICES, USA" is arranged in a circular pattern around the eagle.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
# NOV 2 1 2007
Ms. Christine Lloyd Regulatory Affairs Specialist Smiths Medical ASD, Incorporated 160 Weymouth Street Rockland, Massachusetts 02370
Re: K071958
Trade/Device Name: Thera-Heat™ Heated Humidifier and Heated Wire Ventilator Breathing Circuits Regulation Number: 21 CFR 868.5450 Regulation Name: Respiratory Gas Humidifier Regulatory Class: II Product Code: BTT, BZE Dated: November 16, 2007 Received: November 19, 2007
Dear Ms. Lloyd:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898, In addition, FDA may publish further announcements concerning your device in the Federal Register.
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Page 2 - Ms. Lloyd
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Office of Compliance at (240) 276-0120. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/industry/support/index.html.
Sincerely yours,
Suon Chno
Chiu Lin, Ph.D.
Director Division of Anesthesiology, General Hospital, Infection Control and Dental Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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### SECTION 4, Indications for Use Statement
# Indications for Use
510(k) Number (if known): K071958 Device Name: Thera-Heat™ Heated Humidifier
Indications for Use:
The Smiths Medical Thera-Heat™ Heated Humidifier device is intended to warm and add humidity to the breathing gases that are administered to the patient. The humidifier is indicated for patients requiring mechanical ventilation, positive pressure breathing assistance of general medical gases
The Smiths Medical Thera-Heat™ Heated Humidifier device is intended for use in hospitals and alternate sites by medically trained healthcare providers.
Prescription Use X (Part 21 CFR 801 Subpart D)
AND/OR
Over-The-Counter Use (21 CFR 807 Subpart C)
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
**_(acting B.C.)**
(Division Sign-Off)
Page 1 of 1
Division of Anesthesiology, General Hospital Infection Control, Dental Devices
510(k) Number: K071952
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# SECTION 4, Indications for Use Statement
# Indications for Use
510(k) Number (if known): ____________________________________________________________________________________________________________________________________________________ Device Name: Heated Wire Ventilator Breathing Circuits
Indications for Use:
Inspiratory heated limb
An adult ventilator Heated Breathing Circuit is intended to warm breathing gases before they enter a patient's airway when used with the Thera-Heat™ Heated Humidifier. The circuit acts as a conduit to warm the gases between the humidification chamber and the patient during mechanical ventilation or positive pressure breathing assistance for use with invasive and noninvasive breathing systems.
#### Inspiratory and Expiratory heated limb
An adult ventilator Heated Breathing Circuit is intended to warm breathing gases before they enter a patient's airway and to warm the breathing gases on return from the patient to the ventilator when used with the Thera-Heat™ Heated Humidifier. The circuit acts as a conduit to warm the gases between the humidification chamber and the patient during mechanical ventilation or positive pressure breathing assistance for use with invasive and non-invasive breathing systems.
Prescription Use X (Part 21 CFR 801 Subpart D)
AND/OR
Over-The-Counter Use (21 CFR 807 Subpart C)
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
***(Acting B.C.)***
(Division Sign-Off)
Division of Anesthesiology, General Hospital Infection Control, Dental Devices
510(k) Number: K671958
Two short videos show you everything — or skip straight to the written tutorial if you'd rather read. You can reopen this any time from the Tutorial button in the top bar.
Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
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Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
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With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
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Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.