Trial · NCT03879538
Nitrous Oxide for the Treatment of Complex Regional Pain Syndrome
NCT03879538, Phase 3, Completed, The Cleveland Clinic; results first posted 2024-02-09
3 sourcestrials-2026-11-12-0.5.0
Cite this record
ConductScience Library. Nitrous Oxide for the Treatment of Complex Regional Pain Syndrome. Trials, record NCT03879538. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT03879538
On this page
Trial
As registered on ClinicalTrials.gov, in the graph's capture of the registry.
- Title
- Nitrous Oxide for the Treatment of Complex Regional Pain Syndrome
- NCT number
- NCT03879538
- Status
- Completed
- Phases
- Phase 3
- Enrollment
- 44 participants, actual
- Lead sponsor
- The Cleveland Clinic
- Conditions
- Complex Regional Pain Syndrome
- Interventions
- Nitrous Oxide, Oxygen
- First posted
- 2019-03-18
- Last updated
- 2024-02-09
- Results first posted
- 2024-02-09
- Limitations and caveats
limitations include the purely subjective nature of pain which was our primary outcome. Validity of the trial thus depends critically on adequacy of blinding. Because many patients can detect inhaled nitrous oxide, we gave all participants midazolam which has similar effects. But it remains possible that some patients could distinguish nitrous oxide from air, and were thus biased.
Source ClinicalTrials.gov
Registered outcomes3
Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.
| List | Outcome | Time frame | Description |
|---|---|---|---|
| Primary | Pain Score | one-week and one-month follow-up time points | scales ranging from 0 - "no pain" to 10 - "worst pain ever" based on the PROMIS-29 v2.0 questionnaire. |
| Secondary | PROMIS-29 Survey Physical Health Z-score, Mental Health Z-score | one-week and one-month follow-ups after treatments were ended | As intermediate scores, T-scores for each of the 7 domains used in the survey need to be estimated from raw data in order to obtain final summary Z-scores measuring physical and mental health. T-scores were obtained from an on-line service provided by the HealthMeasures Scoring Service (https://www.assessmentcenter.net/ac\_scoringservice). Physical and mental summary Z-scores were calculated using the formulas given in the document titled "Calculating physical and mental health summary scores for PROMIS-29 v2.0 and v2.1" (dated on August 8, 2018) by Karen L. Spritzer and Ron D. Hays from the website HealthMeasures.net. High T-scores indicates more of the concept being measured which can be either desirable or undesirable outcome, e.g., high T-score on fatigue is undesirable whereas desirable for physical function. Z-scores are standard scores with mean of 0 and SD of 1 in reference population. High Z-scores are desirable for either physical or mental health. |
| Secondary | PGIC Scale | one-week and one-month follow-ups. | patient disease perception as measured by the Patient's Global Impression of Change (PGIC) survey (a seven-point scale ranging from 1 - "no change or condition has gotten worse" to 7 - "very much improve"). |
Source ClinicalTrials.gov
Outcomes3
Each outcome the trial posted results for, in ClinicalTrials.gov's words.
| Type | Outcome | Time frame | Population | Units | Measured as |
|---|---|---|---|---|---|
| PRIMARY | Pain Score | one-week and one-month follow-up time points | A few patients had missing primary outcome measurements. The Mean (SD) values presented here was based on available raw data. In our formal analysis of treatment effect on primary outcome, we used multiple imputation procedures to impute missing primary outcome values. | score on a scale | MEAN |
| SECONDARY | PROMIS-29 Survey Physical Health Z-score, Mental Health Z-score | one-week and one-month follow-ups after treatments were ended | A few patients had missing values due to withdrawal from the study or failure of follow-up contact. | z-score | MEAN |
| SECONDARY | PGIC Scale | one-week and one-month follow-ups. | A few patients had missing values due to withdrawal from the study or study participants can not be reached for follow-up with phone calls. | score on a scale | MEDIAN |
Source ClinicalTrials.gov
Results by group16
Each measurement the trial posted, group by group, in the words and numbers it posted.
| Outcome | Group | Category | Value | Spread | Units |
|---|---|---|---|---|---|
| Pain Score | The Nitrous Oxide Group | one-week follow-up | 5.9 | Standard Deviation 1.5 | score on a scale |
| Pain Score | The Control Group | one-week follow-up | 6.0 | Standard Deviation 2.5 | score on a scale |
| Pain Score | The Nitrous Oxide Group | one-month follow-up | 6.5 | Standard Deviation 2.0 | score on a scale |
| Pain Score | The Control Group | one-month follow-up | 6.8 | Standard Deviation 2.2 | score on a scale |
| PROMIS-29 Survey Physical Health Z-score, Mental Health Z-score | The Nitrous Oxide Group | Physical health Z-score at one-week follow-up | -1.4 | Standard Deviation 0.71 | z-score |
| PROMIS-29 Survey Physical Health Z-score, Mental Health Z-score | The Control Group | Physical health Z-score at one-week follow-up | -1.4 | Standard Deviation 0.78 | z-score |
| PROMIS-29 Survey Physical Health Z-score, Mental Health Z-score | The Nitrous Oxide Group | Physical health Z-score at one-month follow-up | -1.4 | Standard Deviation 0.58 | z-score |
| PROMIS-29 Survey Physical Health Z-score, Mental Health Z-score | The Control Group | Physical health Z-score at one-month follow-up | -1.5 | Standard Deviation 0.68 | z-score |
| PROMIS-29 Survey Physical Health Z-score, Mental Health Z-score | The Nitrous Oxide Group | Mental health Z-score at one-week follow-up | -1.01 | Standard Deviation 0.81 | z-score |
| PROMIS-29 Survey Physical Health Z-score, Mental Health Z-score | The Control Group | Mental health Z-score at one-week follow-up | -0.91 | Standard Deviation 1.00 | z-score |
1 to 10 of 16Source ClinicalTrials.gov
See all 16 results by groupParticipant flow6
How many started, completed or left each group, period by period.
| Period | Milestone | Group | Participants | Units counted |
|---|---|---|---|---|
| Overall Study | STARTED | The Nitrous Oxide Group | 20 | |
| Overall Study | STARTED | The Control Group | 24 | |
| Overall Study | COMPLETED | The Nitrous Oxide Group | 20 | |
| Overall Study | COMPLETED | The Control Group | 24 | |
| Overall Study | NOT COMPLETED | The Nitrous Oxide Group | 0 | |
| Overall Study | NOT COMPLETED | The Control Group | 0 |
Source ClinicalTrials.gov
Adverse events0
Each adverse event the trial posted, group by group: the participants affected out of those at risk.
None in this release.
Adverse event totals6
The totals the trial posted for each group.
| Total | Group | Affected | At risk |
|---|---|---|---|
| Total, all-cause mortality | The Nitrous Oxide Group | 0 | 20 |
| Total, all-cause mortality | The Control Group | 0 | 24 |
| Total, other adverse events | The Nitrous Oxide Group | 0 | 20 |
| Total, other adverse events | The Control Group | 0 | 24 |
| Total, serious adverse events | The Nitrous Oxide Group | 0 | 20 |
| Total, serious adverse events | The Control Group | 0 | 24 |
Source ClinicalTrials.gov
Papers0
The papers the trial lists on ClinicalTrials.gov.
None in this release.
Grants0
The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.
None in this release.
Trial comparisons2
Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.
| Comparison | Source |
|---|---|
| The Nitrous Oxide Group vs The Control Group: deaths from any cause | Trial comparisons |
| The Nitrous Oxide Group vs The Control Group: serious adverse events | Trial comparisons |
Tests0
The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.
None in this release.
Data dates
The day each source was copied for this release.
Sources 3
- ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
- ClinicalTrials.govNo license stated
- NIH RePORTER's clinical studies and project filesPublic domain
Each source's terms
- ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
- ClinicalTrials.govnone stated
- NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)
ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.
For software
Read this trial from software.
The record and each of its lists are JSON, twenty rows a page. No key.
GET https://conductscience.org/api/trials/v1/NCT03879538
GET https://conductscience.org/api/trials/v1/NCT03879538/registered