Demand-Driven Method for Gas Delivery in a Dental Setting

NCT04305990 | Unknown

• 1 other identifier: 00038876
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

This study compares two methods of gas delivery in a dental setting: 1) demand-driven (DD) and 2) free-flow (FF). Nitrous oxide and oxygen sedation (NOS) is a common form of minimal sedation for adult and paediatric patients undergoing dental procedures. In order for NOS devices to be utilized during dental treatment, dentists must be able to provide gas flow to the patient, and subsequently scavenge used and unused gasses. Gas delivery is via a nasal mask, since the oral cavity must be accessible to the dentist throughout treatment. Current devices for NOS in the dental setting utilize a free-flow gas method, where nitrous oxide and oxygen are released continuously from their tanks. The flow rate is set by the dentist according to the patient's minute ventilation needs, and unused and exhaled gasses are scavenged via the nasal mask. The demand-driven gas flow method, where inspiration triggers gas flow, has been used successfully in other medical settings, such as in obstetrics, medical emergencies, and for patients with chronic obstructive pulmonary disease. However, in these settings the mask used covers both the nose and mouth, and patients can trigger the demand-driven method through inspiration of the nose or mouth. The demand-driven gas flow method has a significant gas-sparing advantage over the free-flow method. With a demand-driven method, the patient dictates the flow rate and gas is only delivered when they are inspiring, compared to the free-flow method which provide gas flow throughout inspiration and expiration. However, the demand-driven method have not been studied in a dental setting where flow can only be triggered through the nose. It is therefore unknown whether it is feasible or comfortable for patients to trigger a demand-driven method nasally when their mouth is open during dental treatment. This study will aim to assess the feasibility and comfort of a nasal demand-driven gas delivery method utilizing 100% oxygen in healthy, adult participants in a simulated dental setting. If the device is feasible and comfortable with 100% oxygen in a simulated dental setting, future research can be conducted to assess its use for NOS for dental treatment.

Conditions

Nitrous Oxide; Dentistry; Drug Delivery System; Comfort; Feasibility; Drug Administration, Inhalation

Outcome Measures

Primary Outcomes (2)

• Comfort of the demand-driven gas delivery mechanism

  To assess patient comfort of breathing through their nose with the demand-driven gas delivery method vs the free-flow method. In order to assess comfort, the patient will report perceived comfort on a 100mm visual analog scale immediately after each device is turned on. We will test for non-inferiority in comfort of the demand-driven as compared to the free-flow delivery method.

  Assessed immediately after breathing through each mechanism for 2 minutes

• Feasibility of the demand-driven gas delivery mechanism

  To assess whether it is feasible for participants to inspire 100% oxygen through a nasal hood when utilizing a demand-driven gas delivery mechanism when their mouth is open, in a simulated dental setting. In order to assess feasibility, we will monitor for the presence or absence end-tidal carbon dioxide at the mouth to confirm whether the patient is breathing through their nose or mouth. Absence of carbon dioxide at the mouth indicates the patient was able to trigger the mechanism and breathe through their nose.

  Procedure (Assessed for the duration of time when the patient is breathing from either delivery system)

Study Arms (2)

Demand-driven delivery followed by free-flow delivery

EXPERIMENTAL

Participants will inspire 100% oxygen through their nose with the gas delivery device set to a demand-driven delivery setting through a nasal hood for 2 minutes followed by inspiration of 100% oxygen through their nose with the gas delivery device set to a free-flow delivery setting through a nasal hood for 2 minutes.

Device: Demand-driven delivery method; Device: Free-flow delivery method

Free-flow delivery followed by demand-driven delivery

EXPERIMENTAL

Participants will inspire 100% oxygen through their nose with the gas delivery device set to a free-flow delivery setting through a nasal hood for 2 minutes followed by inspiration of 100% oxygen through their nose with the gas delivery device set to a free-flow delivery setting through a nasal hood for 2 minutes.

Device: Demand-driven delivery method; Device: Free-flow delivery method

Interventions

Demand-driven delivery method DEVICE

The gas delivery device is set to the demand-driven setting. Patients must inspire through their nose to trigger the flow of gas.

Demand-driven delivery followed by free-flow delivery; Free-flow delivery followed by demand-driven delivery

Free-flow delivery method DEVICE

The gas delivery device is set to a free-flow setting. Gas flows through the system at a rate determined by the operator. Standard flow rate is 6 liters per minute. Patients do not need to inspire through their nose to trigger the flow of gas.

Demand-driven delivery followed by free-flow delivery; Free-flow delivery followed by demand-driven delivery

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Participants must be adults, 18 years of age or older.
• Participants must be ASA I (a normal, healthy patient) or ASA II (a patient with mild systemic disease).

You may not qualify if:

• Participants who are ASA III (a patient with a severe systemic disease that is not life-threatening) or higher.
• Participants who indicate they are claustrophobic.
• Participants with nasal obstruction of both nostrils.

Sponsors & Collaborators

• University of Toronto: lead
• O-Two Medical Technologies: collaborator

Study Sites (1)

University of Toronto, Faculty of Dentistry

Toronto, Ontario, M5G 1G6, Canada

Location

Related Publications (13)

• Wilson S, Gosnell ES. Survey of American Academy of Pediatric Dentistry on Nitrous Oxide and Sedation: 20 Years Later. Pediatr Dent. 2016 Oct 15;38(5):385-392.

  PMID: 28206894 BACKGROUND

• Malamed SF, Clark MS. Nitrous oxide-oxygen: a new look at a very old technique. J Calif Dent Assoc. 2003 May;31(5):397-403.

  PMID: 12839232 BACKGROUND

• Becker DE, Rosenberg M. Nitrous oxide and the inhalation anesthetics. Anesth Prog. 2008 Winter;55(4):124-30; quiz 131-2. doi: 10.2344/0003-3006-55.4.124.

  PMID: 19108597 BACKGROUND

• Clark MS, Brunick A. Handbook of Nitrous Oxide and Oxygen Sedation. 5th Edition ed: Elsevier Health Sciences; 2019.

  BACKGROUND

• Tiep BL, Nicotra MB, Carter R, Phillips R, Otsap B. Low-concentration oxygen therapy via a demand oxygen delivery system. Chest. 1985 May;87(5):636-8. doi: 10.1378/chest.87.5.636.

  PMID: 3921316 BACKGROUND

• van der Kooy J, De Graaf JP, Kolder ZM, Witters KD, Fitzpatrick E, Duvekot JJ, Dons-Sinke IJ, Steegers EA, Bonsel GJ. A newly developed scavenging system for administration of nitrous oxide during labour: safe occupational use. Acta Anaesthesiol Scand. 2012 Aug;56(7):920-5. doi: 10.1111/j.1399-6576.2012.02668.x. Epub 2012 Mar 7.

  PMID: 22404276 BACKGROUND

• Dallal GD. Randomization.com [updated July 15, 2008. Available from: ⟨http://www.randomization.com/⟩.

  BACKGROUND

• Doig GS, Simpson F. Randomization and allocation concealment: a practical guide for researchers. J Crit Care. 2005 Jun;20(2):187-91; discussion 191-3. doi: 10.1016/j.jcrc.2005.04.005.

  PMID: 16139163 BACKGROUND

• Humphris GM, Morrison T, Lindsay SJ. The Modified Dental Anxiety Scale: validation and United Kingdom norms. Community Dent Health. 1995 Sep;12(3):143-50.

  PMID: 7584581 BACKGROUND

• Humphris GM, Dyer TA, Robinson PG. The modified dental anxiety scale: UK general public population norms in 2008 with further psychometrics and effects of age. BMC Oral Health. 2009 Aug 26;9:20. doi: 10.1186/1472-6831-9-20.

  PMID: 19709436 BACKGROUND

• Humphris G, Crawford JR, Hill K, Gilbert A, Freeman R. UK population norms for the modified dental anxiety scale with percentile calculator: adult dental health survey 2009 results. BMC Oral Health. 2013 Jun 24;13:29. doi: 10.1186/1472-6831-13-29.

  PMID: 23799962 BACKGROUND

• King K, Humphris G. Evidence to confirm the cut-off for screening dental phobia using the Modified Dental Anxiety Scale. Soc sci dent. 2010;1(1):21-8.

  BACKGROUND

• Hendrix JM, Garmon EH. American Society of Anesthesiologists Physical Status Classification System. 2025 Feb 11. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from http://www.ncbi.nlm.nih.gov/books/NBK441940/

  PMID: 28722969 BACKGROUND

MeSH Terms

Conditions

Respiratory Aspiration

Condition Hierarchy (Ancestors)

Respiration Disorders; Respiratory Tract Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Carilynne Yarascavitch, BSc DDS MSc

  University of Toronto

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Ayala Y Rubin, BA DDS

CONTACT

(1)-647-988-5202; ayala.rubin@utoronto.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Participants will not be told the order the gas flow delivery method (DD or FF) they will be receive. To assist with masking participants, the same device and nasal hood will be used throughout, they will be told to face forward away from the device and device display, which indicates the setting of the gas flow. It will not be feasible to blind the researcher as the researcher will need to change the device setting (FF or DD).
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor, Specialty Program Director, Dental Anaesthesia, Faculty of Dentistry

Model Details: The study design is a within-subjects, single-blinded, randomized controlled trial. Each participant will receive both the free-flow (FF) and demand-driven (DD) gas delivery methods in a randomized sequence.

Study Record Dates

• First Submitted: March 10, 2020
• First Posted: March 12, 2020
• Study Start: March 1, 2020
• Primary Completion: October 1, 2020
• Study Completion: October 1, 2020
• Last Updated: March 12, 2020

Record last verified: 2020-03

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)