An interventional study of Nitrous Oxide 0% and Nitrous oxide 33% in Amnesia, sponsored by State University of New York at Buffalo. Completed at 1 site in United States. Open to participants aged 6 Years to 12 Years. Per ClinicalTrials.gov, last updated 2026-06-30.
Sponsored by State University of New York at Buffalo · Not applicable, Interventional, and Other
The investigators are conducting a study to investigate the amnestic effects of 2 different concentrations of nitrous oxide in children before induction of anesthesia in a prospective double-blinded placebo controlled study.
Children of age group 6-12 will be randomly divided in 3 groups, First group will be Placebo , second group will be nitrous oxide end tidal 33% and third group will be nitrous oxide 66%. Each group will be divided into 2 subgroups randomly with either a flavored or unflavored mask for induction.
All children will be told a joke before the mask is applied, with the answer provided after the end-tidal nitrous oxide concentration reaches the randomized concentration (0, 33 or 66%) for at least one minute. At that point, the child will randomized to be either shown a picture of one of four animals (predetermined randomly) or a food will be stated aloud. For the animal, the child will be asked to name the animal aloud. The child's response (yes or no to a response and whether the item is correctly named) will be recorded. If the child does not respond, the name of the animal will be stated out loud. For the food, one of four foods will be named aloud and child will be asked to repeat the name. The child's response (named or not) will be recorded. Anesthesia will continue with the designated nitrous oxide concentration combined with 8% Sevoflurane.
When the child is ready for discharge from the recovery room and recovered from anesthesia, a nurse or doctor who is blinded to the treatment group assignment will ask the child to recall the joke and answer. The child will then be asked if they were shown any animals and if so, which animal? If the child cannot recall an animal, the child will be asked to name the first animal that comes to mind. The child will then be shown pictures of four animals and asked to identify one. The child will be asked if they heard any foods when they went to sleep? If the child cannot recall hearing any foods recited, the first letter of the food will be shown: B _ _ _ _ _ . If the child does not recall any foods, then the child will be given the names of four foods that begin with the letter B and asked to pick one. Finally, the child will be asked about any odors in the mask during anesthesia. If he/she does not recall, then four odors will be read out and the child asked to identify any one. Additionally, the children will be asked whether they recall any odors on the mask as they were anesthetized. The order of items questioned in the recovery period will follow the same order as in the OR.
22 studies on the registry are indexed under Amnesia; 2 are open to participants now.
This study's enrollment of 90 is above the median of 62 across 19 interventional studies indexed under Amnesia.
Browse Amnesia studies →State University of New York at Buffalo is the lead sponsor of 294 studies on the registry; 63 are open to participants now.
Of its 19 completed or terminated interventional studies of FDA-regulated products, 15 (79%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
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.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Nitrous oxide 0% by mask for 2 minutes while showing pictures and telling jokes.
Drug: Nitrous Oxide 0%
Nitrous oxide 33% for 2 minutes while showing pictures and telling jokes.
Drug: Nitrous oxide 33%
Nitrous oxide 66% for 2 minutes while showing pictures and telling jokes.
Drug: Nitrous oxide 66%
Behavior: recall at discharge from hospital will be tested for the content of photos and a joke told while breathing a mask
Also known as: Placebo
Behavior: recall at discharge from hospital will be tested for the content of photos and a joke told while breathing a mask
Also known as: low concentration Nitrous oxide
Behavior: recall at discharge from hospital will be tested for the content of photos and a joke told while breathing a mask
Also known as: high concentration Nitrous oxide
Explicit Memory
Explicit memory will be tested during the recovery period (once the child has fully recovered from anesthesia but before discharge from hospital) by a blinded observer who will ask the child whether they smelled za bad odor while they breathed through the mask.
Time frame: After full recovery from anesthesia (generally by 2 hours after termination of anesthesia), but before discharge from hospital all variables will be assessed
Explicit Memory
Explicit memory will be tested for the child recalling the riddle and answer after the study
Time frame: After recovery from anesthesia (in recovery room or before discharge from hospital) within 4 hours of anesthesia completion
Explicit Memory if the Child Remembered Being Shown an Animal in a Photo
The child will be shown the photo of an animal while they were breathing through the mask and then asked to recall which animal they were shown in the photo during the mask induction
Time frame: 2 hours after anesthesia
Explicit Memory of the Name of a Food That Begins With the Letter "b"
The child will be asked if they recall hearing the name of a good that began with the letter "b" while breathing the mask
Time frame: 2 hours after anesthesia
| Milestone | 0% Nitrous Oxide | 30% Nitrous Oxide | 60% Nitrous Oxide |
|---|---|---|---|
| Started | 30 | 29 | 31 |
| Completed | 30 | 29 | 31 |
| Not completed | 0 | 0 | 0 |
Explicit memory will be tested during the recovery period (once the child has fully recovered from anesthesia but before discharge from hospital) by a blinded observer who will ask the child whether they smelled za bad odor while they breathed through the mask.
| participants | Nitrous Oxide 0% | Nitrous Oxide 33% | Nitrous Oxide 66% |
|---|---|---|---|
| Explicit Memory | 7 | 1 | 2 |
Explicit memory will be tested for the child recalling the riddle and answer after the study
| Participants | 0% N2O | 33% N2O | 60% N2O |
|---|---|---|---|
| Explicit Memory | 21 | 21 | 14 |
The child will be shown the photo of an animal while they were breathing through the mask and then asked to recall which animal they were shown in the photo during the mask induction
| Participants | 0% N2O | 33% N2O | 60% N2O |
|---|---|---|---|
| Explicit Memory if the Child Remembered Being Shown an Animal in a Photo | 27 | 21 | 14 |
The child will be asked if they recall hearing the name of a good that began with the letter "b" while breathing the mask
| Participants | Explicit Recall a Food That Started With a "b" With 0% N2O | Explicit Recall a Food That Started With a "b" With 33% N2O | Explicit Recall a Food That Started With a "b" With 66% N2O |
|---|---|---|---|
| Explicit Memory of the Name of a Food That Begins With the Letter "b" | 10 | 15 | 7 |
Collected over During the day of surgery, 1 day.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Nitrous Oxide 0% | 0/30 (0%) | 0/30 (0%) | 0/30 (0%) |
| Nitrous Oxide 30% | 0/29 (0%) | 0/29 (0%) | 0/29 (0%) |
| Nitrous Oxide 60% | 0/31 (0%) | 0/31 (0%) | 0/31 (0%) |
Children 6-12 years, ASA physical status 1 or 2
| Age, Continuous(years) | 0% Nitrous Oxide | 30% Nitrous Oxide | 60% Nitrous Oxide | Total |
|---|---|---|---|---|
| Mean | 8.3 ± 1.9 | 8.2 ± 1.6 | 8.2 ± 1.9 | 8.2 ± 1.8 |
| Sex: Female, Male(Participants) | 0% Nitrous Oxide | 30% Nitrous Oxide | 60% Nitrous Oxide | Total |
|---|---|---|---|---|
| Female | 15 | 23 | 17 | 55 |
| Male | 15 | 6 | 14 | 35 |
| Region of Enrollment(participants) | 0% Nitrous Oxide | 30% Nitrous Oxide | 60% Nitrous Oxide | Total |
|---|---|---|---|---|
| United States | 30 | 29 | 31 | 90 |
Plan to share: No
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Studies of the drug tested here: Nitrous Oxide
State University of New York at Buffalo →