A Trial of Self-Adjusted Nitrous Versus Placebo During Office Vasectomy

A Single-Blind Randomized Placebo Controlled Trial of Self-Adjusted Nitrous Oxide During Office Vasectomy

The goal of this clinical trial is to see if nitrous oxide is safe and effective to use during during vasectomies performed in a clinic/in-office setting.

This trial will compare self-administered nitrous oxide versus a placebo (oxygen) during office vasectomy.

The main questions it aims to answer are:

• Whether self-administered low dose (20-45%) nitrous oxide (SANO) reduces intraoperative anxiety and catastrophizing during office vasectomy.
• To examine whether SANO reduces intraoperative pain or alters procedure duration, the rate of adverse events, or urologists' perception of ease and patient tolerance of the procedure.

Participants will be asked to complete multiple surveys pre-procedure, intra-procedure, and post-procedure.

Study Overview

• Status: Recruiting
• Conditions: Vasectomy
• Intervention / Treatment: Drug: Nitrous Oxide; Drug: Oxygen

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02115
      • Recruiting
      • Brigham and Women's Hospital
      • Contact: Alexandra J Berger Eberhardt, MD; Phone Number: 617-983-4521; Email: ajberger@bwh.harvard.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 18 - 85 at the time of screening
• Desiring vasectomy for family planning purposes
• Able to understand and complete patient questionnaires
• Willing and able to provide written consent to participate in the study

Exclusion Criteria:

• Patients with unilateral absence of the vas deferens
• Patients who are deemed by study surgeons to have anatomy no amendable for office procedure
• Patients who decline office vasectomy and request monitored anesthesia care
• Patients taking benzodiazepine or narcotic medication daily or within 24 hours of the procedure
• Patients with contraindications to nitrous oxide including:
• Inner ear, bariatric, or eye surgery within the past 2 weeks
• Current emphysematous blebs
• Severe B-12 deficiency
• History of bleomycin chemotherapy within the last year
• Class III or higher heart failure

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Nitrous Oxide; Self-Administered Nitrous Oxide	Drug: Nitrous Oxide; Self-Administered Nitrous Oxide
Placebo Comparator: Placebo (Oxygen); Self-Administered Placebo (Oxygen)	Drug: Oxygen; Self-Administered Oxygen

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Difference in VAS-A During Vasectomy Procedure and S-PCS Immediately After Vasectomy Procedure, Comparing Participants Receiving and Not Receiving Self-Administered Low Dose Nitrous Oxide	Measuring the mean difference in Visual Analog Scale for Anxiety (VAS-A) during the vasectomy procedure and the Situational Pain Catastrophizing Scale (S-PCS) immediately after the vasectomy procedure, comparing those receiving and not receiving self-administered low dose nitrous oxide. Intra-Procedure (Immediately After Injection of Local Anesthesia) Visual Analog Scale for Anxiety (VAS-A) (Zero is equivalent to no anxiety and 10 indicates the worst anxiety) Intra-Procedure (In Between Left and Right Sides of Procedure) Visual Analog Scale for Anxiety (VAS-A) (Zero is equivalent to no anxiety and 10 indicates the worst anxiety) Post-Procedure (10 Minutes After Procedure Completion, to Allow for Nitrous Oxide to be Metabolized); Situational Pain Catastrophizing Scale (S-PCS) (Zero is equivalent to not at all and 4 indicates all the time); Visual Analog Scale for Anxiety (VAS-A) (Zero is equivalent to no anxiety and 10 indicates the worst anxiety)	Intra-Procedure (Immediately After Injection of Local Anesthesia) - Post-Procedure (10 Minutes After Procedure Completion, Allow for Nitrous Oxide to be Metabolized)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Difference in Visual Analog Scale for Pain (VAS-P) Intra-Procedurally, Comparing Participants Receiving and Not Receiving Self-Administered Low Dose Nitrous Oxide	Intra-Procedure (Immediately After Injection of Local Anesthesia) Visual Analog Scale for Pain (VAS-P) (Zero is equivalent to no pain and 10 indicates the worst pain) Intra-Procedure (In Between Left and Right Sides of Procedure) Visual Analog Scale for Pain (VAS-P) (Zero is equivalent to no pain and 10 indicates the worst pain)	Intra-Procedure (Immediately After Injection of Local Anesthesia) - Intra-Procedure (In Between Left and Right Sides of Procedure)
Mean Difference in VAS-P and STAI Pre- and Post-Procedurally, Comparing Participants Receiving and Not Receiving Self-Administered Low Dose Nitrous Oxide	Pre-Procedure (Day of Procedure, Immediately Prior); Visual Analog Scale for Pain (VAS-P) (Zero is equivalent to no pain and 10 indicates the worst pain); State Trait Anxiety Inventory (STAI) (1 is equivalent to not at all and 4 indicates very much) Post-Procedure (10 Minutes After Procedure Completion, Allow for Nitrous Oxide to be Metabolized); Visual Analog Scale for Pain (VAS-P) (Zero is equivalent to no pain and 10 indicates the worst pain); State Trait Anxiety Inventory (STAI) (1 is equivalent to not at all and 4 indicates very much)	Pre-Procedure (Day of Procedure, Immediately Prior) - Post-Procedure (10 Minutes After Procedure Completion, Allow for Nitrous Oxide to be Metabolized)
Mean Difference in 30-Day Complications / Adverse Events, Comparing Participants Receiving and Not Receiving Self-Administered Low Dose Nitrous Oxide	Measured using the The Common Terminology Criteria for Adverse Events (CTCAE) grading scale (v5.0). CTCAE v5.0 (1 is equivalent to mild and 5 indicates death related to AE)	Study Enrollment - 30 Days After Vasectomy
Urologist: Ease of Procedure, Comparing Participants Receiving and Not Receiving Self-Administered Low Dose Nitrous Oxide	Post-Procedure, Day of Vasectomy Ease of Procedure (1 is equivalent to the urologist determining the procedure went worse than expected and 3 indicates the urologist determines the procedure went better than expected)	Post-Procedure, Day of Vasectomy
Urologist: Patient Tolerance, Comparing Participants Receiving and Not Receiving Self-Administered Low Dose Nitrous Oxide	Patient Tolerance (1 is equivalent to the urologist determining the patient's tolerance for the procedure was worse than expected and 3 indicates the urologist determines the patient's tolerance for the procedure was better than expected)	Post-Procedure, Day of Vasectomy
Mean Difference in Duration of Procedure, Comparing Participants Receiving and Not Receiving Self-Administered Low Dose Nitrous Oxide		Intra-Procedure (Immediately After Injection of Local Anesthesia) - Post-Procedure (10 Minutes After Procedure Completion, Allow for Nitrous Oxide to be Metabolized)

Collaborators and Investigators

• Sponsor: Alexandra J. Berger Eberhardt, MD
• Investigators: Study Chair: Alexandra J Berger Eberheardt, MD, Brigham and Women's Hospital

Study record dates

Study Major Dates

• Study Start (Actual): October 20, 2025
• Primary Completion (Estimated): May 1, 2028
• Study Completion (Estimated): May 1, 2030

Study Registration Dates

• First Submitted: November 10, 2025
• First Submitted That Met QC Criteria: November 17, 2025
• First Posted (Actual): November 24, 2025

Study Record Updates

• Last Update Posted (Actual): November 24, 2025
• Last Update Submitted That Met QC Criteria: November 17, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Nitrous Oxide; Men's Health; Vasectomy
• Additional Relevant MeSH Terms: Inorganic Chemicals; Nitrogen Compounds; Elements; Oxides; Oxygen Compounds; Chalcogens; Gases; Nitrogen Oxides; Nitrous Oxide; Oxygen
• Other Study ID Numbers: 2025P000258

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No