A Phase 1 interventional study of Nitrous Oxide and Nitrous Oxide in Hyperalgesia, sponsored by Air Liquide Santé International. Completed at 2 sites in Germany. Open to male participants aged 18 Years to 40 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-09-11.
Sponsored by Air Liquide Santé International (part of Air Liquide) · Phase 1, Interventional, and Treatment
Evaluation of the effects of 35%/15%/50% N2O/N2/O2 mixtures on the area of hyperalgesia induced by remifentanil in the CCES (Continuous Cutaneous Electrical Stimulation) model in 20 healthy volunteers.
The duration of participation for each volunteer is expected to be around 9 weeks with the performance of 4 experimental session 2 weeks apart.
The selection visit will last half a day; each experimental session will last half a day; the study end will last 2 hours maximum.
Single site, exploratory, comparative, double-blind, randomised, cross-over study. Three physicians will be involved in the conduct of this study:
Design: A group of 20 assessable subjects who will undergo 4 randomised experimental sessions of CCES on 4 separate study days, 2 weeks apart preceded by a 2 week period between selection and first experimental session and followed by a 1 week period between last experimental session and study end.
After the selection visit, each visit corresponds to one of the 4 experimental sessions named A, B, C, D differing by the gas mixture inhaled and the intravenous medicine administered.
The order of these experimental sessions A, B, C, D, will be assigned according to a pre-established list that the investigator will not know.
Each experimental session includes a set-up-phase followed by an evaluation phase.
The set up phase will last 20 mn during each an electrical stimulation will generate a spontaneous pain: every 2 minutes the electrical stimulation will increase and the subject will be asked to rate the pain on a visual scale from 0 to 100. When a stable levels of pain intensity will be reached, the regimen of the electrical stimulation will be kept constant up to the end of the experimental session.
The Evaluation phase will last 160 mn : the electrical stimulation will be constant during 160 mn as detailed above. During this phase the subject will inhale a gas mixture with a face mask during 60 minutes combined with an intravenous administration of medicine during 30 mn starting at the same time.
Every 5 minutes the subject will be asked to rate the pain and at predefined times the spontaneous pain and the area of allodynia and hyperalgesia will be measured and recorded as well as safety parameters (transcutaneous oxygen saturation, respiratory parameters, sedation score, blood pressure and heart rate).
The 4 experimental sessions named A, B, C, D differ by the gas mixture inhaled and the intravenous medicine administered.
For the placebo session, inhaled gas mixture will be 50%/50% N2/O2 and intravenous administration will be an isotonic saline solution.
For the three other sessions, inhaled gas mixture will differ from a session to the other one (35%/15%/50% N2O/N2/O2 or 50%/50% N2/O2 or 50%/50% N2O/O2), and remifentanil will be administered intravenously at each of these sessions.
166 studies on the registry are indexed under Hyperalgesia; 14 are open to participants now.
This study's enrollment of 20 is below the median of 50 across 142 interventional studies indexed under Hyperalgesia.
Browse Hyperalgesia studies →Air Liquide Santé International is the lead sponsor of 23 studies on the registry; 1 is open to participants now.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Remifentanil at 0.1 µg/kg/min Tested drug (N2O 35%): 35%/15%/50% N2O/N2/O2
Drug: Nitrous Oxide
Remifentanil at 0.1 µg/kg/min Gas active control (N2O 50%):50%/50% N2O/O2
Drug: Nitrous Oxide
35%
50%
Also known as: Kalinox
Hyperalgesia
\- Hyperalgesia will be assessed by using a metal rod,(in unit cm).
Time frame: at T0, T10, T25, T40, T55, T70, T95, T110, T125, T140 and T155 minutes at each experimental session which will last half day
transcutaneous oxygen saturation
By monitoring pulse oximetry device
Time frame: From T0 to T160 minutes, at 5 minute intervals at each experimental session which will last half day
respiration rate
Respiration rate
Time frame: From T0 to T160 minutes, at 5 minute intervals at each experimental session which will last half day
systolic and diastolic blood pressures
systolic and diastolic blood pressures
Time frame: From T0 to T160 minutes, at 5 minute intervals at each experimental session which will last half day
Heart rate
Measured by cardioscope
Time frame: From T0 to T160 minutes, at 5 minute intervals at each experimental session which will last half day
sedation score
sedation score
Time frame: From T0 to T160 minutes, at 5 minute intervals at each experimental session which will last half day
The record gives a start of Jan 2012, a primary completion of Apr 2012 and a completion of Apr 2012. It does not say whether these dates are actual or estimated.
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This study is completed, as verified in Sep 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Nitrous Oxide
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