AnesthesiaNCT06449157
Chocolate or Sevoflurane: Use of Parosmia to Facilitate More Cooperative Inhalation Inductions in Children
A study testing Inhalation induction with parosmia in people with Anesthesia and Pediatrics, run by Johns Hopkins University at 1 site in United States.
Trial summary
Children undergoing surgery and anesthesia are often negatively impacted by anxiety and fear in the preoperative period. Routine inhalational anesthetic induction is a unique aspect of pediatric anesthesia. Inhalation inductions are usually initiated with sevoflurane with or without nitrous oxide. Read more about this study
- Who is it for?
- Ages 5 to 13 years
- Conditions the study is for
- Anesthesia, Pediatrics
- What is being tested?
- Inhalation induction with parosmia
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 50 participants
- Where
- 1 siteUnited States
- Study dates
- 10 Oct 2024to 7 Aug 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 5 to 13 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Ages of 5-12 years old
- American Society of Anesthesiologist physical status classification system (ASA) I and II
- Patients coming from home
Who cannot join
- Patients undergoing emergent surgery
- Patients who have not adequately maintained preoperative nothing per mouth/os (NPO) status
- Patients with inability to communicate verbally
- Tracheostomy patients
- ASA III , IV, V patients
Trial locations and contacts
1 site in 1 country.
About this study
Children undergoing surgery and anesthesia are often negatively impacted by anxiety and fear in the preoperative period. Routine inhalational anesthetic induction is a unique aspect of pediatric anesthesia. Inhalation inductions are usually initiated with sevoflurane with or without nitrous oxide. While less pungent than other volatile agents, sevoflurane at high concentrations and flows used for inhalation inductions still causes children to often repel from the smell. This can lead to an unpleasant interaction and cause heightened anxiety for any subsequent procedures.
Olfactory senses are processed in the hippocampus and amygdala and tied to emotion and memory. Parosmia is the distortion of smell perception which can utilized to the pediatric anesthesiologists advantage. It has been demonstrated that using this phenomenon, the anesthesiologist can induce a better smell for the child leading to improved cooperation during an inhalation induction. However, limitations of this study include lack of randomization, small sample size, and use of a nominal scale of yes or no for face mask acceptance. The investigators identified no other studies to validate this potentially powerful tool to optimize anesthetic induction for pediatric patients.
The overall objective of this pilot randomized trial is to determine the feasibility of parosmia during inhalation inductions to decrease perioperative stress for children and provide key pilot data to power a larger study to determine effectiveness of parosmia during inhalation inductions to decrease perioperative stress for children and provide key pilot data to power a larger study to determine effectiveness of parosmia.
- Conditions
- Anesthesia, Pediatrics
- Being tested
- Inhalation induction with parosmia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Inhalation induction with parosmiaOther
The experimental group will then be told that the patient's favorite smell will be put into the face mask via the "magical machine". The patient will be asked to take a deep breath thinking about that smell and then introduce sevoflurane. The patient will be asked if the chosen flavor is smelled and their response will be noted.
| Study group | Role | What they receive |
|---|---|---|
| Inhalation induction with parosmia | Experimental | The experimental group will be told about a magical machine that can change the smell of the mask to any flavor the patient desires. The participant will be asked to take a deep breath thinking about that smell and then sevoflurane will be introduced. The patient will be asked if the the chosen flavor is smelled and the response will be noted. Receives: Other: Inhalation induction with parosmia |
| Standard inhalation induction | No intervention | Standard inhalation induction. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Perioperative anxiety as assessed by the Modified Yale Preoperative Anxiety Scale-Short Form (mYPAS-SF)
The modified Yale Preoperative Anxiety Scale-Short Form (mYPAS-SF) will be used to evaluate perioperative anxiety. Patients are evaluated in 4 domains: activity (score 1,2,3, or 4), vocalizations (score 1,2,3,4,5 or 6), emotional expressivity (1,2,3 or 4), and state of apparent arousal (1,2,3, or 4), with higher numbers indicating the highest severity within that item. Each score is calculated by dividing each item rating by the highest possible rating (i.e., 6 for the "vocalizations" item and 4 for all other items), adding all the produced values, dividing by 5, and multiplying by 100. This calculation produces a score ranging from 23.33 to 100, with higher values indicating higher anxiety.
Measured: perioperatively
Secondary outcomes (3)
Number of antiemetic mediations administered post-operatively
Measuring statistical difference in 1) number of antiemetic medications administered
Measured: immediately after the surgery
Type and total dose of opioids administered post-operatively
Type and total dose of opioids administered
Measured: immediately after the surgery
Length of time (minutes) to post-anesthesia care unit (PACU) discharge
Length of time from admission to PACU discharge between the control group and the intervention group
Measured: admission to the PACU through discharge from the PACU (<2 hours post-operatively)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Jun 2024
- Study start10 Oct 2024
- Primary completion7 Aug 2025
- Study completion7 Aug 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for AnesthesiaStudies of the same condition, open and under way.
- More trials run by Johns Hopkins UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 50 participants (actual)
Sponsor and investigators
- Lead sponsor
- Johns Hopkins University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Pooja O'Neil, MD, Principal investigator, Johns Hopkins School of Medicine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06449157
- Sponsor's protocol ID
- IRB00434506
- Status last verified
- Aug 2025
- First submitted
- 31 May 2024
- Last updated
- 11 Aug 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 11 Aug 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Chocolate or Sevoflurane: Use of Parosmia to Facilitate More Cooperative Inhalation Inductions in Children
- ClinicalTrials.gov ID
- NCT06449157
- Acronym / sponsor ID
- IRB00434506
- Conditions
- Anesthesia, Pediatrics
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 50 participants (actual)
- Lead sponsor
- Johns Hopkins UniversityUniversity, hospital or other
- Study start
- 10 Oct 2024 (actual)
- Primary completion
- 7 Aug 2025 (actual)
- Study completion
- 7 Aug 2025 (actual)
- First posted
- 7 Jun 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Children undergoing surgery and anesthesia are often negatively impacted by anxiety and fear in the preoperative period. Routine inhalational anesthetic induction is a unique aspect of pediatric anesthesia. Inhalation inductions are usually initiated with sevoflurane with or without nitrous oxide. While less pungent than other volatile agents, sevoflurane at high concentrations and flows used for inhalation inductions still causes children to often repel from the smell. This can lead to an unpleasant interaction and cause heightened anxiety for any subsequent procedures.
Olfactory senses are processed in the hippocampus and amygdala and tied to emotion and memory. Parosmia is the distortion of smell perception which can utilized to the pediatric anesthesiologists advantage. It has been demonstrated that using this phenomenon, the anesthesiologist can induce a better smell for the child leading to improved cooperation during an inhalation induction. However, limitations of this study include lack of randomization, small sample size, and use of a nominal scale of yes or no for face mask acceptance. The investigators identified no other studies to validate this potentially powerful tool to optimize anesthetic induction for pediatric patients.
The overall objective of this pilot randomized trial is to determine the feasibility of parosmia during inhalation inductions to decrease perioperative stress for children and provide key pilot data to power a larger study to determine effectiveness of parosmia during inhalation inductions to decrease perioperative stress for children and provide key pilot data to power a larger study to determine effectiveness of parosmia.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Inhalation induction with parosmia | Experimental | Other: Inhalation induction with parosmiaThe experimental group will be told about a magical machine that can change the smell of the mask to any flavor the patient desires. The participant will be asked to take a deep breath thinking about that smell and then sevoflurane will be introduced. The patient will be asked if the the chosen flavor is smelled and the response will be noted. |
| Standard inhalation induction | No intervention | –Standard inhalation induction. |
Who may qualify
- Ages
- 5 to 13 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (3 listed)
- Ages of 5-12 years old
- American Society of Anesthesiologist physical status classification system (ASA) I and II
- Patients coming from home
Key exclusion criteria (5 listed)
- Patients undergoing emergent surgery
- Patients who have not adequately maintained preoperative nothing per mouth/os (NPO) status
- Patients with inability to communicate verbally
- Tracheostomy patients
- ASA III , IV, V patients
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Inhalation induction with parosmiaThe experimental group will then be told that the patient's favorite smell will be put into the face mask via the "magical machine". The patient will be asked to take a deep breath thinking about that smell and then introduce sevoflurane. The patient will be asked if the chosen flavor is smelled and their response will be noted. | Other | Inhalation induction with parosmia |
Primary outcome
Perioperative anxiety as assessed by the Modified Yale Preoperative Anxiety Scale-Short Form (mYPAS-SF)
Time frame: perioperatively
The modified Yale Preoperative Anxiety Scale-Short Form (mYPAS-SF) will be used to evaluate perioperative anxiety. Patients are evaluated in 4 domains: activity (score 1,2,3, or 4), vocalizations (score 1,2,3,4,5 or 6), emotional expressivity (1,2,3 or 4), and state of apparent arousal (1,2,3, or 4), with higher numbers indicating the highest severity within that item. Each score is calculated by dividing each item rating by the highest possible rating (i.e., 6 for the "vocalizations" item and 4 for all other items), adding all the produced values, dividing by 5, and multiplying by 100. This calculation produces a score ranging from 23.33 to 100, with higher values indicating higher anxiety.
3 secondary outcomes
Number of antiemetic mediations administered post-operatively
Time frame: immediately after the surgery
Type and total dose of opioids administered post-operatively
Time frame: immediately after the surgery
Length of time (minutes) to post-anesthesia care unit (PACU) discharge
Time frame: admission to the PACU through discharge from the PACU (<2 hours post-operatively)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 11 Aug 2025.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Pooja O'Neil, MD principal investigator
Johns Hopkins School of Medicine
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Inhalation induction with parosmia in people with Anesthesia and Pediatrics, run by Johns Hopkins University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 11 Aug 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Perioperative anxiety as assessed by the Modified Yale Preoperative Anxiety Scale-Short Form (mYPAS-SF) (time frame: perioperatively). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 Aug 2025.